AIM: To evaluate the accuracy of endoscopic ultrasound (EUS) for staging of gastric cancers. METHODS: Only EUS studies confirmed by surgery were selected. Only studies from which a 2 × 2 table could be constructe...AIM: To evaluate the accuracy of endoscopic ultrasound (EUS) for staging of gastric cancers. METHODS: Only EUS studies confirmed by surgery were selected. Only studies from which a 2 × 2 table could be constructed for true positive, false negative, false positive and true negative values were included. Articles were searched in Medline, Pubmed, Ovid journals, Cumulative index for nursing & allied health literature, International pharmaceutical abstracts, old Medline, Medline nonindexed citations, and Cochrane control trial registry. Two reviewers independently searched and extracted data. The differences were resolved by mutual agreement. 2 × 2 tables were constructed with the data extracted from each study. Meta-analysis for the accuracy of EUS was analyzed by calculating pooled estimates of sensitivity, specifi city, likelihood ratios, and diagnostic odds ratio. Pooling was conducted by both the Mantel-Haenszel method (fi xed effects model) and DerSimonian Laird method (random effects model). The heterogeneity of studies was tested using Cochran's Q test based upon inverse variance weights. RESULTS: Initial search identified 1620 reference articles and of these, 376 relevant articles were selected and reviewed. Twenty-two studies (n = 1896) which met the inclusion criteria were included in this analysis. Pooled sensitivity of T1 was 88.1% (95% CI: 84.5-91.1) and T2 was 82.3% (95% CI: 78.2-86.0). For T3, pooled sensitivity was 89.7% (95% CI: 87.1-92.0). T4 hada pooled sensitivity of 99.2% (95% CI: 97.1-99.9). For nodal staging, the pooled sensitivity for N1 was 58.2% (95% CI: 53.5-62.8) and N2 was 64.9% (95% CI: 60.8-68.8). Pooled sensitivity to diagnose distant metastasis was 73.2% (95% CI: 63.2-81.7). The P for chi-squared heterogeneity for all the pooled accuracy estimates was > 0.10. CONCLUSION: EUS results are more accurate with advanced disease than early disease. If EUS diagnoses advanced disease, such as T4 disease, the patient is 500 times more likely to have true anatomic stage of T4 disease.展开更多
With technological advances in basic research,the intricate mechanism of secondary delayed spinal cord injury(SCI)continues to unravel at a rapid pace.However,despite our deeper understanding of the molecular changes ...With technological advances in basic research,the intricate mechanism of secondary delayed spinal cord injury(SCI)continues to unravel at a rapid pace.However,despite our deeper understanding of the molecular changes occurring after initial insult to the spinal cord,the cure for paralysis remains elusive.Current treatment of SCI is limited to early administration of high dose steroids to mitigate the harmful effect of cord edema that occurs after SCI and to reduce the cascade of secondary delayed SCI.R ecent evident-based clinical studies have cast doubt on the clinical benefit of steroids in SCI and intense focus on stem cell-based therapy has yielded some encouraging results.An array of mesenchymal stem cells(MSCs)from various sources with novel and promising strategies are being developed to improve function after SCI.In this review,we briefly discuss the pathophysiology of spinal cord injuries and characteristics and the potential sources of MSCs that can be used in the treatment of SCI.We will discuss the progress of MSCs application in research,focusing on the neuroprotective properties of MSCs.Finally,we will discuss the results from preclinical and clinical trials involving stem cell-based therapy in SCI.展开更多
AIM: To identify the variants in U rase 1 (UGT1A1) gene in Gilbert's syndrome (GS) and to estimate the association between homozygosity for TA insertion and GS in India, as well as the frequency of TA insertion ...AIM: To identify the variants in U rase 1 (UGT1A1) gene in Gilbert's syndrome (GS) and to estimate the association between homozygosity for TA insertion and GS in India, as well as the frequency of TA insertion and its impact among normal controls in India. METHODS: Ninety-five GS cases and 95 normal controls were selected. Liver function and other tests were done. The promoter and all 5 exons of UGT1A1 gene were resequenced. Functional assessment of a novel trinucleotide insertion was done by in silico analysis and by estimating UGT1A1 promoter activity carried out by ludferase reporter assay of appropriate constructs in Hep G2 cell line. RESULTS: Among the GS patients, 80% were homozygous for the TA insertion, which was several-fold higher than reports from other ethnic groups. The mean UCB level was elevated among individuals with only one copy of this insertion, which was not significantly different from those with two copies. Many new DNA variants in UGT1A1 gene were discovered, including a trinucleotide (CAT) insertion in the promoter found in a subset (10%) of GS patients, but not among normal controls. In-silico analysis showed marked changes in the DNA-folding of the promoter and functional analysis showed a 20-fold reduction in transcription efficiency of UGT1A1 gene resulting from this insertion, thereby significantly elevating the UCB level. CONCLUSION: The genetic epidemiology of GS is variable across ethnic interactions among UGT1A1 groups and the epistatic promoter variants modulate bilirubin glucuronidation.展开更多
AIM: To compare the efficacy of pentoxifylline and prednisolone in the treatment of severe alcoholic hepatitis, and to evaluate the role of different liver function scores in predicting prognosis.METHODS: Sixty-eigh...AIM: To compare the efficacy of pentoxifylline and prednisolone in the treatment of severe alcoholic hepatitis, and to evaluate the role of different liver function scores in predicting prognosis.METHODS: Sixty-eight patients with severe alcoholic hepatitis (Maddrey score ≥ 32) received pentoxifylline (n = 34, group Ⅰ) or prednisolone (n = 34, group Ⅱ) for 28 d in a randomized double-blind controlled study, and subsequently in an open study (with a tapering dose of prednisolone) for a total of 3 mo, and were followed up over a period of 12 mo.RESULTS: Twelve patients in group Ⅱ died at the end of 3 mo in contrast to five patients in group Ⅰ. The probability of dying at the end of 3 mo was higher in group Ⅱ as compared to group Ⅰ (35.29% vs 14.71%, P = 0.04; log rank test). Six patients in group I developed hepatorenal syndrome as compared to none in group Ⅰ. Pentoxifylline was associated with a significantly lower model for end-stage liver disease (MELD) score at the end of 28 d of therapy (15.53± 3.63 vs 17.78± 4.56, P=0.04). Higher baseline Maddrey score was associated with increased mortality.CONCLUSION: Reduced mortality, improved risk-benefit profile and renoprotective effects of pentoxifylline compared with prednisolone suggest that pentoxifylline is superior to prednisolone for treatment of severe alcoholic hepatitis.展开更多
BACKGROUND: Laparoscopic pancreaticoduodenectomy(LPD)is a safe procedure. Oncological safety of LPD is still a matter for debate. This study aimed to compare the oncological outcomes,in terms of adequacy of resecti...BACKGROUND: Laparoscopic pancreaticoduodenectomy(LPD)is a safe procedure. Oncological safety of LPD is still a matter for debate. This study aimed to compare the oncological outcomes,in terms of adequacy of resection and recurrence rate following LPD and open pancreaticoduodenectomy(OPD).METHODS: Between November 2005 and April 2009, 12LPDs(9 ampullary and 3 distal common bile duct tumors)were performed. A cohort of 12 OPDs were matched for age,gender, body mass index(BMI) and American Society of Anesthesiologists(ASA) score and tumor site.RESULTS: Mean tumor size LPD vs OPD(19.8 vs 19.2 mm,P=0.870). R0 resection was achieved in 9 LPD vs 8 OPD(P=1.000). The mean number of metastatic lymph nodes and total number resected for LPD vs OPD were 1.1 vs 2.1(P=0.140)and 20.7 vs 18.5(P=0.534) respectively. Clavien complications grade I/II(5 vs 8), III/IV(2 vs 6) and pancreatic leak(2 vs 1)were statistically not significant(LPD vs OPD). The mean high dependency unit(HDU) stay was longer in OPD(3.7 vs 1.4 days,P〈0.001). There were 2 recurrences each in LPD and OPD(logrank,P=0.983). Overall mortality for LPD vs OPD was 3 vs 6(log-rank, P=0.283) and recurrence-related mortality was 2 vs 1.There was one death within 30 days in the OPD group secondary to severe sepsis and none in the LPD group.CONCLUSIONS: Compared to open procedure, LPD achieved a similar rate of R0 resection, lymph node harvest and longterm recurrence for tumors less than 2 cm. Though technically challenging, LPD is safe and does not compromise oncological outcome.展开更多
An attempt was made to observe the effect of pre-harvest bagging with spun-bound fabric bags on color and quality of Delicious apple. Bagging was done about a month before harvesting and removed 3-day before harvestin...An attempt was made to observe the effect of pre-harvest bagging with spun-bound fabric bags on color and quality of Delicious apple. Bagging was done about a month before harvesting and removed 3-day before harvesting. Bagged and non-bagged fruits were stored at 2℃ ± 1℃ and 90%-95% RH. Observations were recorded on color and fruit quality attributes such as total phenolics, AOX activity, fruit Ca contents, LOX activity, SSC and ascorbic acid contents at harvest and during storage. Our studies have revealed that bagged fruits have better color development (Hunter “a” = 52) than non-bagged fruits at harvest (Hunter “a” = 38), which declined slightly during storage. Similarly, at harvest, bagged fruits contained high amounts of Ca (5.38 mg/100g) and total phenolics (9.3 mg GAE/100gpulp) exhibited higher AOX activity (12.6 μmoles Trolox g-1), and had better SSC and ascorbic acid contents than non-bagged fruits, and there was a decline in all recorded parameters during storage. Bagged fruits exhibited lower LOX activity (1.38 μmoles min-1 g-1 FW) at harvest than non-bagged fruits (2.14 μmoles min-1 g-1 FW), indicating that non-bagged fruits were more senescent than bagged fruits. Further, LOX activity increased during storage both in bagged and non-bagged apples but increase in LOX activity was slower in bagged apples than in non-bagged apples.展开更多
The Materials Genome Initiative(MGI)advanced a new paradigm for materials discovery and design,namely that the pace of new materials deployment could be accelerated through complementary efforts in theory,computation,...The Materials Genome Initiative(MGI)advanced a new paradigm for materials discovery and design,namely that the pace of new materials deployment could be accelerated through complementary efforts in theory,computation,and experiment.Along with numerous successes,new challenges are inviting researchers to refocus the efforts and approaches that were originally inspired by the MGI.In May 2017,the National Science Foundation sponsored the workshop“Advancing and Accelerating Materials Innovation Through the Synergistic Interaction among Computation,Experiment,and Theory:Opening New Frontiers”to review accomplishments that emerged from investments in science and infrastructure under the MGI,identify scientific opportunities in this new environment,examine how to effectively utilize new materials innovation infrastructure,and discuss challenges in achieving accelerated materials research through the seamless integration of experiment,computation,and theory.This article summarizes key findings from the workshop and provides perspectives that aim to guide the direction of future materials research and its translation into societal impacts.展开更多
In recent years,a new wave of bioactive,biocompatibility and biodegradable metallic materials were developed for orthopedic applications.Pure Magnesium,Magnesium alloys,Magnesium alloy-based composites are extensive m...In recent years,a new wave of bioactive,biocompatibility and biodegradable metallic materials were developed for orthopedic applications.Pure Magnesium,Magnesium alloys,Magnesium alloy-based composites are extensive material to the biomedical applications,by virtue of its high biocompatibility and reasonable strength.Pure magnesium,Magnesium alloys can corrode too fast during the physiological conditions and loses their properties before bone heal.The new era for the development of magnesium-based composites can satisfy the orthopedic applications.Magnesium-based composites,as bio-materials,can produce adjustable mechanical properties like Ultimate tensile strength,ductility,elastic modulus,and corrosion resistance in the physiological conditions.In the Mg based composites,the matrix materials are biomedical magnesium alloys base like Mg-Ca,Mg-Al,Mg-Zn,and Mg-REE alloy and The reinforcements are based on hydroxyapatite(HAP),calcium polyphosphate(CPP),andβ-tricalcium phosphate(β-TCP)particles.This comprehensive review is focused on different grades of biodegradable magnesium matrix composites including their mechanical properties and corrosion resistance.展开更多
The type 2 immune response is critical for host defense against large parasites such as helminths.On the other hand,dysregulation of the type 2 immune response may cause immunopathological conditions,including asthma,...The type 2 immune response is critical for host defense against large parasites such as helminths.On the other hand,dysregulation of the type 2 immune response may cause immunopathological conditions,including asthma,atopic dermatitis,rhinitis,and anaphylaxis.Thus,a balanced type 2 immune response must be achieved to mount effective protection against invading pathogens while avoiding immunopathology.The classical model of type 2 immunity mainly involves the differentiation of type 2 T helper(Th2)cells and the production of distinct type 2 cytokines,including interleukin-4(IL-4),IL-5,and IL-13.Group 2 innate lymphoid cells(ILC2s)were recently recognized as another important source of type 2 cytokines.Although eosinophils,mast cells,and basophils can also express type 2 cytokines and participate in type 2 immune responses to various degrees,the production of type 2 cytokines by the lymphoid lineages,Th2 cells,and ILC2s in particular is the central event during the type 2 immune response.In this review,we discuss recent advances in our understanding of how ILC2s and Th2 cells orchestrate type 2 immune responses through direct and indirect interactions.展开更多
AIM:To study the epidemiologic changes of gastroenteropancreatic neuroendocrine tumors(GEP-NET)in Germany,we analyzed two time periods 1976-1988 and1998-2006.METHODS:We evaluated epidemiological data of GEP-NET from t...AIM:To study the epidemiologic changes of gastroenteropancreatic neuroendocrine tumors(GEP-NET)in Germany,we analyzed two time periods 1976-1988 and1998-2006.METHODS:We evaluated epidemiological data of GEP-NET from the former East German National Cancer Registry(DDR Krebsregister,1976-1988)and its successor,the Joint Cancer Registry(GKR,1998-2006),which was founded after German reunification.Due to a particularly substantial database the epidemiological data from the federal states of Mecklenburg-Western Pomerania,Saxony,Brandenburg and Thuringia,covering a population of more than 10.8 million people,were analyzed.Survival probabilities were calculated using life table analysis.In addition,GEP-NET patients were evaluated for one or more second(non-GEP-NET)primary malignancies.RESULTS:A total of 2821 GEP neuroendocrine neoplasms were identified in the two registries.The overall incidence increased significantly between 1976 and2006 from 0.31(per 100.000 inhabitants per year)to2.27 for men and from 0.57 to 2.38 for women.In the later period studied(2004-2006),the small intestine was the most common site.Neuroendocrine(NE)neoplasms of the small intestine showed the largest absolute increase in incidence,while rectal NE neoplasms exhibited the greatest relative increase.Only the incidence of appendiceal NET in women showed little change between 1976 and 2006.Overall survival of patients varied for sex,tumor site and the two periods studied but improved significantly over time.Interestingly,about 20%of the GEP-NET patients developed one or more second malignancies.Their most common location was the gastrointestinal tract.GEP-NET patients without second malignancies fared better than those with one or more of them.CONCLUSION:The number of detected GEP-NET increased about 5-fold in Germany between 1976 and2006.At the same time,their anatomic distribution changed,and the survival of GEP-NET patients improved significantly.Second malignancies are common and influence the overall survival of GEP-NET patients.Thus,GEP-NET 展开更多
We elucidate here the process-structure-property relationships in three-dimensional(3 D) implantable titanium alloy biomaterials processed by electron beam melting(EBM) that is based on the principle of additive m...We elucidate here the process-structure-property relationships in three-dimensional(3 D) implantable titanium alloy biomaterials processed by electron beam melting(EBM) that is based on the principle of additive manufacturing. The conventional methods for processing of biomedical devices including freeze casting and sintering are limited because of the difficulties in adaptation at the host site and difference in the micro/macrostructure, mechanical, and physical properties with the host tissue. In this regard, EBM has a unique advantage of processing patient-specific complex designs, which can be either obtained from the computed tomography(CT) scan of the defect site or through a computeraided design(CAD) program. This review introduces and summarizes the evolution and underlying reasons that have motivated 3 D printing of scaffolds for tissue regeneration.The overview comprises of two parts for obtaining ultimate functionalities. The first part focuses on obtaining the ultimate functionalities in terms of mechanical properties of 3 D titanium alloy scaffolds fabricated by EBM with different characteristics based on design, unit cell, processing parameters, scan speed, porosity, and heat treatment. The second part focuses on the advancement of enhancing biological responses of these 3 D scaffolds and the influence of surface modification on cell-material interactions. The overview concludes with a discussion on the clinical trials of these 3 D porous scaffolds illustrating their potential in meeting the current needs of the biomedical industry.展开更多
Microalgae has been consumed in human diet for thousands of years.It is an under-exploited crop for production of dietary foods.Microalgae cultivation does not compete with land and resources required for traditional ...Microalgae has been consumed in human diet for thousands of years.It is an under-exploited crop for production of dietary foods.Microalgae cultivation does not compete with land and resources required for traditional crops and has a superior yield compared to terrestrial crops.Its high protein content has exhibited a huge potential to meet the dietary requirements of growing population.Apart from being a source of protein,presence of various bio-active components in microalgae provide an added health benefit.This review describes various microalgal sources of proteins and other bio-active components.One of the heavily studied group of bio-active components are pigments due to their anticarcenogenic,antioxidative and antihypertensive properties.Compared to various plant and floral species,microalgae contain higher amounts of pigments.Microalgal derived proteins have complete Essential Amino Acids(EAA)profiles and their protein content is higher than conventional sources such as meat,poultry and dairy products.However,microalgal based functional foods have not flooded the market.The lack of awareness coupled with scarce incentives for producers result in under-exploitation of microalgal potential.Application of microalgal derived components as dietary and nutraceutical supplements is discussed comprehensively.展开更多
AIM: To critically appraise the published randomized, controlled trials on the prophylactic effectiveness of the non-steroidal anti-inflammatory drugs(NSAIDs), in reducing the risk of post-endoscopic retrograde cholan...AIM: To critically appraise the published randomized, controlled trials on the prophylactic effectiveness of the non-steroidal anti-inflammatory drugs(NSAIDs), in reducing the risk of post-endoscopic retrograde cholangiopancreatography(ERCP) pancreatitis. METHODS: A systematic literature search(MEDLINE, Embase and the Cochrane Library, from inception of the databases until May 2015) was conducted to identify randomized, clinical trials investigating the role of NSAIDs in reducing the risk of post-ERCP pancreatitis. Random effects model of the meta-analysis was carried out, and results were presented as odds ratios(OR) with corresponding 95%CI.RESULTS: Thirteen randomized controlled trials on 3378 patients were included in the final meta-analysis. There were 1718 patients in the NSAIDs group and 1660 patients in non-NSAIDs group undergoing ERCP. The use of NSAIDs(through rectal route or intramuscular route) was associated with the reduced risk of post-ERCP pancreatitis [OR, 0.52(0.38-0.72), P = 0.0001]. The use of pre-procedure NSAIDs was effective in reducing approximately 48% incidence of post-ERCP pancreatitis, number needed to treat were 16 with absolute risk reduction of 0.05. But the risk of post-ERCP pancreattis was reduced by 55% if NSAIDs were administered after procedure. Similarly, diclofenac was more effective(55%) prophylactic agent compared to indomethacin(41%).CONCLUSION: NSAIDs seem to have clinically proven advantage of reducing the risk of post-ERCP pancreatitis.展开更多
In this study we describe the fabrication of a variety of open-cellular titanium alloy(Ti-6 Al-4 V) implants,both reticular mesh and foam structures, using electron beam melting(EBM). These structures allow for th...In this study we describe the fabrication of a variety of open-cellular titanium alloy(Ti-6 Al-4 V) implants,both reticular mesh and foam structures, using electron beam melting(EBM). These structures allow for the elimination of stress shielding by adjusting the porosity(or density) to produce an elastic modulus(or stiffness) to match that of both soft(trabecular) and hard(cortical) bone, as well as allowing for bone cell ingrowth, increased cell density, and all-matrix interactions; the latter involving the interplay between bone morphogenetic protein(BMP-2) and osteoblast functions. The early formation and characterization of elementary vascular structures in an aqueous hydrogel matrix are illustrated.Preliminary results for both animal(sheep) and human trials for a number of EBM-fabricated, and often patient-specific Tialloy implants are also presented and summarized. The results, while preliminary, support the concept and development of successful, porous, engineered "living" implants.展开更多
Rice sheath blight disease (ShB), caused by Rhizoctonia solani, gives rise to significant grain yield losses. The present study evaluated the efficacy of Integral, the commercial liquid formulation of Bacillus subti...Rice sheath blight disease (ShB), caused by Rhizoctonia solani, gives rise to significant grain yield losses. The present study evaluated the efficacy of Integral, the commercial liquid formulation of Bacillus subtilis strain MBI 600, against rice ShB and for plant growth promotion. In greenhouse studies, four log concentrations of Integral (from 2.2×10^6 to 2.2×10^9 cfu/mL) were used as seed treatment (ST). After 25 d, seedlings were dipped (SD) into Integral prior to transplanting. At 30 d after transplanting (DAT), leaf sheaths were inoculated with immature sclerotia of the pathogen. At 45 DAT, a foliar spray (FS) with Integral was applied to some treatments. The fungicide control was 50% carbendazim at 1.0 g/L, and a nontreated control was also included. Overall, there were 10 treatments, each with five replications. ShB severity was rated at 52 DAT, and seedling height and number of tillers per plant were rated at 60 DAT. In 2009, two field trials evaluated Integral at 2.2×10^8 and 2.2×10^9 cfu/mL. Integral was applied as ST, and seedlings were produced in a nursery bed. After 32 d, seedlings were treated with Integral as SD and transplanted into 10 m^2 blocks. Foliar sprays were given at 45 and 60 DAT. There were seven treatments, each with eight replications arranged as a factorial randomized complete block design. At 20 DAT, the plots were broadcast inoculated with R. solani produced on rice grains. Seedling height before transplanting, ShB severity at 90 DAT, and grain yield at harvest were recorded. Integral at 2.2×10^9 cfu/mL provided significant increase of seedling heights over other treatments under greenhouse conditions. The Integral treatments of ST + SD + FS at 2.2×10^9 cfu/mL significantly suppressed ShB over other treatments. In field studies, Integral provided significant increase of seedling height in nursery, and number of tillers per plant, compared with the control. ShB severity was significantly suppressed with higher concentrations of Integral compared t展开更多
Background The natural history of the profile and development of the miscellaneous complications. iver cirrhosis in China has not been we complications of liver cirrhosis as we understood. This study aimed to elucidat...Background The natural history of the profile and development of the miscellaneous complications. iver cirrhosis in China has not been we complications of liver cirrhosis as we understood. This study aimed to elucidate as the mortality of those cirrhotics with Methods We assembled data from the clinical characteristics, especially from the profile complications of cirrhosis on admission, and collected information by telephone or interview with patients and/or their family members in clinic to evaluate the development of complications in 920 patients enrolled in a prospective non-randomized cohort study, and followed up from June 2006 to October 2010. Mortality was calculated using Kaplan-Meier analysis and Cox regress analysis. We employed both of the Child-Pugh scoring system and model for end-stage liver disease (MELD) scoring system to compare with the accordance and veracity between liver function and the long-term outcome. Results On admission, only 7.4% patients had no complications, 44.5% patients with one complication (ascites, esophageal/gastric varices or hepatocellular carcinoma), 33.8% patients with two coexisting complications, and 7.5% patients had complications concurrently with ascites, esophageal/gastric varices and hepatocellular carcinoma. During the follow-up (mean follow-up time was 17 months, ranging from 1.0 to 52.2 months) of all the patients, 37.5% patients survived without new complications, 62.5% patients had new complications, and the overall mortality was 53.9%. Patients with one or more complications had higher mortality (total mortality, 1-year or 3-year mortality) and shorter mean survival time than those without any complication; the major cause of mortality of these cirrhotic patients was hepatocellular carcinoma (59%). Evaluated with the Child-Pugh score system, the total mortality in those with the scores more than 12 (class C) was 71.4%, the 1-year and 3-year mortalities were 57.1% and 71.4% respectively; while evaluated with the MELD scoring system, th展开更多
AIM:To evaluate the accuracy of endoscopic ultrasound (EUS), EUS-fine needle aspiration (FNA) in evaluating mediastinal lymphadenopathy. METHODS:Only EUS and EUS-FNA studies confirmed by surgery or with appropriate fo...AIM:To evaluate the accuracy of endoscopic ultrasound (EUS), EUS-fine needle aspiration (FNA) in evaluating mediastinal lymphadenopathy. METHODS:Only EUS and EUS-FNA studies confirmed by surgery or with appropriate follow-up were selected. Articles were searched in Medline, Pubmed, and Cochrane control trial registry. Only studies from which a 2 × 2 table could be constructed for true positive, false negative, false positive and true negative values were included. Two reviewers independently searched and extracted data. The differences were resolved by mutual agreement. Meta-analysis for the accuracy of EUS was analyzed by calculating pooled estimates of sensitivity, specificity, likelihood ratios, and diagnostic odds ratios. Pooling was conducted by both Mantel-Haenszel method (fixed effects model) and DerSimonian Laird method (random effects model). The heterogeneity of studies was tested using Cochran’s Q test based upon inverse variance weights. RESULTS:Data was extracted from 76 studies (n = 9310) which met the inclusion criteria. Of these, 44 studies used EUS alone and 32 studies used EUS-FNA. FNA improved the sensitivity of EUS from 84.7% (95% CI:82.9-86.4) to 88.0% (95% CI:85.8-90.0). With FNA, the specificity of EUS improved from 84.6% (95% CI:83.2-85.9) to 96.4% (95% CI:95.3-97.4). The P forchi-squared heterogeneity for all the pooled accuracy estimates was > 0.10. CONCLUSION:EUS is highly sensitive and specific for the evaluation of mediastinal lymphadenopathy and FNA substantially improves this. EUS with FNA should be the diagnostic test of choice for evaluating mediastinal lymphadenopathy.展开更多
The rapid consumption of fossil fuel and increased environmental damage caused by it have given a strong impetus to the growth and development of fuelefficient vehicles. Hybrid electric vehicles (HEVs) have evolved fr...The rapid consumption of fossil fuel and increased environmental damage caused by it have given a strong impetus to the growth and development of fuelefficient vehicles. Hybrid electric vehicles (HEVs) have evolved from their inchoate state and are proving to be a promising solution to the serious existential problem posed to the planet earth. Not only do HEVs provide better fuel economy and lower emissions satisfying environmental legislations, but also they dampen the effect of rising fuel prices on consumers. HEVs combine the drive powers of an internal combustion engine and an electrical machine. The main components of HEVs are energy storage system, motor, bidirectional converter and maximum power point trackers (MPPT, in case of solar-powered HEVs). The performance of HEVs greatly depends on these components and its architecture. This paper presents an extensive review on essential components used in HEVs such as their architectures with advantages and disadvantages, choice of bidirectional converter to obtain high efficiency, combining ultracapacitor with battery to extend the battery life, traction motors’ role and their suitability for a particular application. Inclusion of photovoltaic cell in HEVs is a fairly new concept and has been discussed in detail. Various MPPT techniques used for solar-driven HEVs are also discussed in this paper with their suitability.展开更多
文摘AIM: To evaluate the accuracy of endoscopic ultrasound (EUS) for staging of gastric cancers. METHODS: Only EUS studies confirmed by surgery were selected. Only studies from which a 2 × 2 table could be constructed for true positive, false negative, false positive and true negative values were included. Articles were searched in Medline, Pubmed, Ovid journals, Cumulative index for nursing & allied health literature, International pharmaceutical abstracts, old Medline, Medline nonindexed citations, and Cochrane control trial registry. Two reviewers independently searched and extracted data. The differences were resolved by mutual agreement. 2 × 2 tables were constructed with the data extracted from each study. Meta-analysis for the accuracy of EUS was analyzed by calculating pooled estimates of sensitivity, specifi city, likelihood ratios, and diagnostic odds ratio. Pooling was conducted by both the Mantel-Haenszel method (fi xed effects model) and DerSimonian Laird method (random effects model). The heterogeneity of studies was tested using Cochran's Q test based upon inverse variance weights. RESULTS: Initial search identified 1620 reference articles and of these, 376 relevant articles were selected and reviewed. Twenty-two studies (n = 1896) which met the inclusion criteria were included in this analysis. Pooled sensitivity of T1 was 88.1% (95% CI: 84.5-91.1) and T2 was 82.3% (95% CI: 78.2-86.0). For T3, pooled sensitivity was 89.7% (95% CI: 87.1-92.0). T4 hada pooled sensitivity of 99.2% (95% CI: 97.1-99.9). For nodal staging, the pooled sensitivity for N1 was 58.2% (95% CI: 53.5-62.8) and N2 was 64.9% (95% CI: 60.8-68.8). Pooled sensitivity to diagnose distant metastasis was 73.2% (95% CI: 63.2-81.7). The P for chi-squared heterogeneity for all the pooled accuracy estimates was > 0.10. CONCLUSION: EUS results are more accurate with advanced disease than early disease. If EUS diagnoses advanced disease, such as T4 disease, the patient is 500 times more likely to have true anatomic stage of T4 disease.
基金Supported by A grant from Illinois Neurological Institute to DHD
文摘With technological advances in basic research,the intricate mechanism of secondary delayed spinal cord injury(SCI)continues to unravel at a rapid pace.However,despite our deeper understanding of the molecular changes occurring after initial insult to the spinal cord,the cure for paralysis remains elusive.Current treatment of SCI is limited to early administration of high dose steroids to mitigate the harmful effect of cord edema that occurs after SCI and to reduce the cascade of secondary delayed SCI.R ecent evident-based clinical studies have cast doubt on the clinical benefit of steroids in SCI and intense focus on stem cell-based therapy has yielded some encouraging results.An array of mesenchymal stem cells(MSCs)from various sources with novel and promising strategies are being developed to improve function after SCI.In this review,we briefly discuss the pathophysiology of spinal cord injuries and characteristics and the potential sources of MSCs that can be used in the treatment of SCI.We will discuss the progress of MSCs application in research,focusing on the neuroprotective properties of MSCs.Finally,we will discuss the results from preclinical and clinical trials involving stem cell-based therapy in SCI.
基金Supported by grants from the Department of Biotechnology, Government of India (to PPM) and the Department of Science & Technology, Government of West Bengal (to AC)
文摘AIM: To identify the variants in U rase 1 (UGT1A1) gene in Gilbert's syndrome (GS) and to estimate the association between homozygosity for TA insertion and GS in India, as well as the frequency of TA insertion and its impact among normal controls in India. METHODS: Ninety-five GS cases and 95 normal controls were selected. Liver function and other tests were done. The promoter and all 5 exons of UGT1A1 gene were resequenced. Functional assessment of a novel trinucleotide insertion was done by in silico analysis and by estimating UGT1A1 promoter activity carried out by ludferase reporter assay of appropriate constructs in Hep G2 cell line. RESULTS: Among the GS patients, 80% were homozygous for the TA insertion, which was several-fold higher than reports from other ethnic groups. The mean UCB level was elevated among individuals with only one copy of this insertion, which was not significantly different from those with two copies. Many new DNA variants in UGT1A1 gene were discovered, including a trinucleotide (CAT) insertion in the promoter found in a subset (10%) of GS patients, but not among normal controls. In-silico analysis showed marked changes in the DNA-folding of the promoter and functional analysis showed a 20-fold reduction in transcription efficiency of UGT1A1 gene resulting from this insertion, thereby significantly elevating the UCB level. CONCLUSION: The genetic epidemiology of GS is variable across ethnic interactions among UGT1A1 groups and the epistatic promoter variants modulate bilirubin glucuronidation.
文摘AIM: To compare the efficacy of pentoxifylline and prednisolone in the treatment of severe alcoholic hepatitis, and to evaluate the role of different liver function scores in predicting prognosis.METHODS: Sixty-eight patients with severe alcoholic hepatitis (Maddrey score ≥ 32) received pentoxifylline (n = 34, group Ⅰ) or prednisolone (n = 34, group Ⅱ) for 28 d in a randomized double-blind controlled study, and subsequently in an open study (with a tapering dose of prednisolone) for a total of 3 mo, and were followed up over a period of 12 mo.RESULTS: Twelve patients in group Ⅱ died at the end of 3 mo in contrast to five patients in group Ⅰ. The probability of dying at the end of 3 mo was higher in group Ⅱ as compared to group Ⅰ (35.29% vs 14.71%, P = 0.04; log rank test). Six patients in group I developed hepatorenal syndrome as compared to none in group Ⅰ. Pentoxifylline was associated with a significantly lower model for end-stage liver disease (MELD) score at the end of 28 d of therapy (15.53± 3.63 vs 17.78± 4.56, P=0.04). Higher baseline Maddrey score was associated with increased mortality.CONCLUSION: Reduced mortality, improved risk-benefit profile and renoprotective effects of pentoxifylline compared with prednisolone suggest that pentoxifylline is superior to prednisolone for treatment of severe alcoholic hepatitis.
文摘BACKGROUND: Laparoscopic pancreaticoduodenectomy(LPD)is a safe procedure. Oncological safety of LPD is still a matter for debate. This study aimed to compare the oncological outcomes,in terms of adequacy of resection and recurrence rate following LPD and open pancreaticoduodenectomy(OPD).METHODS: Between November 2005 and April 2009, 12LPDs(9 ampullary and 3 distal common bile duct tumors)were performed. A cohort of 12 OPDs were matched for age,gender, body mass index(BMI) and American Society of Anesthesiologists(ASA) score and tumor site.RESULTS: Mean tumor size LPD vs OPD(19.8 vs 19.2 mm,P=0.870). R0 resection was achieved in 9 LPD vs 8 OPD(P=1.000). The mean number of metastatic lymph nodes and total number resected for LPD vs OPD were 1.1 vs 2.1(P=0.140)and 20.7 vs 18.5(P=0.534) respectively. Clavien complications grade I/II(5 vs 8), III/IV(2 vs 6) and pancreatic leak(2 vs 1)were statistically not significant(LPD vs OPD). The mean high dependency unit(HDU) stay was longer in OPD(3.7 vs 1.4 days,P〈0.001). There were 2 recurrences each in LPD and OPD(logrank,P=0.983). Overall mortality for LPD vs OPD was 3 vs 6(log-rank, P=0.283) and recurrence-related mortality was 2 vs 1.There was one death within 30 days in the OPD group secondary to severe sepsis and none in the LPD group.CONCLUSIONS: Compared to open procedure, LPD achieved a similar rate of R0 resection, lymph node harvest and longterm recurrence for tumors less than 2 cm. Though technically challenging, LPD is safe and does not compromise oncological outcome.
文摘An attempt was made to observe the effect of pre-harvest bagging with spun-bound fabric bags on color and quality of Delicious apple. Bagging was done about a month before harvesting and removed 3-day before harvesting. Bagged and non-bagged fruits were stored at 2℃ ± 1℃ and 90%-95% RH. Observations were recorded on color and fruit quality attributes such as total phenolics, AOX activity, fruit Ca contents, LOX activity, SSC and ascorbic acid contents at harvest and during storage. Our studies have revealed that bagged fruits have better color development (Hunter “a” = 52) than non-bagged fruits at harvest (Hunter “a” = 38), which declined slightly during storage. Similarly, at harvest, bagged fruits contained high amounts of Ca (5.38 mg/100g) and total phenolics (9.3 mg GAE/100gpulp) exhibited higher AOX activity (12.6 μmoles Trolox g-1), and had better SSC and ascorbic acid contents than non-bagged fruits, and there was a decline in all recorded parameters during storage. Bagged fruits exhibited lower LOX activity (1.38 μmoles min-1 g-1 FW) at harvest than non-bagged fruits (2.14 μmoles min-1 g-1 FW), indicating that non-bagged fruits were more senescent than bagged fruits. Further, LOX activity increased during storage both in bagged and non-bagged apples but increase in LOX activity was slower in bagged apples than in non-bagged apples.
文摘The Materials Genome Initiative(MGI)advanced a new paradigm for materials discovery and design,namely that the pace of new materials deployment could be accelerated through complementary efforts in theory,computation,and experiment.Along with numerous successes,new challenges are inviting researchers to refocus the efforts and approaches that were originally inspired by the MGI.In May 2017,the National Science Foundation sponsored the workshop“Advancing and Accelerating Materials Innovation Through the Synergistic Interaction among Computation,Experiment,and Theory:Opening New Frontiers”to review accomplishments that emerged from investments in science and infrastructure under the MGI,identify scientific opportunities in this new environment,examine how to effectively utilize new materials innovation infrastructure,and discuss challenges in achieving accelerated materials research through the seamless integration of experiment,computation,and theory.This article summarizes key findings from the workshop and provides perspectives that aim to guide the direction of future materials research and its translation into societal impacts.
文摘In recent years,a new wave of bioactive,biocompatibility and biodegradable metallic materials were developed for orthopedic applications.Pure Magnesium,Magnesium alloys,Magnesium alloy-based composites are extensive material to the biomedical applications,by virtue of its high biocompatibility and reasonable strength.Pure magnesium,Magnesium alloys can corrode too fast during the physiological conditions and loses their properties before bone heal.The new era for the development of magnesium-based composites can satisfy the orthopedic applications.Magnesium-based composites,as bio-materials,can produce adjustable mechanical properties like Ultimate tensile strength,ductility,elastic modulus,and corrosion resistance in the physiological conditions.In the Mg based composites,the matrix materials are biomedical magnesium alloys base like Mg-Ca,Mg-Al,Mg-Zn,and Mg-REE alloy and The reinforcements are based on hydroxyapatite(HAP),calcium polyphosphate(CPP),andβ-tricalcium phosphate(β-TCP)particles.This comprehensive review is focused on different grades of biodegradable magnesium matrix composites including their mechanical properties and corrosion resistance.
基金by the Division of Intramural Research of NIAID(US National Institutes of Health).
文摘The type 2 immune response is critical for host defense against large parasites such as helminths.On the other hand,dysregulation of the type 2 immune response may cause immunopathological conditions,including asthma,atopic dermatitis,rhinitis,and anaphylaxis.Thus,a balanced type 2 immune response must be achieved to mount effective protection against invading pathogens while avoiding immunopathology.The classical model of type 2 immunity mainly involves the differentiation of type 2 T helper(Th2)cells and the production of distinct type 2 cytokines,including interleukin-4(IL-4),IL-5,and IL-13.Group 2 innate lymphoid cells(ILC2s)were recently recognized as another important source of type 2 cytokines.Although eosinophils,mast cells,and basophils can also express type 2 cytokines and participate in type 2 immune responses to various degrees,the production of type 2 cytokines by the lymphoid lineages,Th2 cells,and ILC2s in particular is the central event during the type 2 immune response.In this review,we discuss recent advances in our understanding of how ILC2s and Th2 cells orchestrate type 2 immune responses through direct and indirect interactions.
文摘AIM:To study the epidemiologic changes of gastroenteropancreatic neuroendocrine tumors(GEP-NET)in Germany,we analyzed two time periods 1976-1988 and1998-2006.METHODS:We evaluated epidemiological data of GEP-NET from the former East German National Cancer Registry(DDR Krebsregister,1976-1988)and its successor,the Joint Cancer Registry(GKR,1998-2006),which was founded after German reunification.Due to a particularly substantial database the epidemiological data from the federal states of Mecklenburg-Western Pomerania,Saxony,Brandenburg and Thuringia,covering a population of more than 10.8 million people,were analyzed.Survival probabilities were calculated using life table analysis.In addition,GEP-NET patients were evaluated for one or more second(non-GEP-NET)primary malignancies.RESULTS:A total of 2821 GEP neuroendocrine neoplasms were identified in the two registries.The overall incidence increased significantly between 1976 and2006 from 0.31(per 100.000 inhabitants per year)to2.27 for men and from 0.57 to 2.38 for women.In the later period studied(2004-2006),the small intestine was the most common site.Neuroendocrine(NE)neoplasms of the small intestine showed the largest absolute increase in incidence,while rectal NE neoplasms exhibited the greatest relative increase.Only the incidence of appendiceal NET in women showed little change between 1976 and 2006.Overall survival of patients varied for sex,tumor site and the two periods studied but improved significantly over time.Interestingly,about 20%of the GEP-NET patients developed one or more second malignancies.Their most common location was the gastrointestinal tract.GEP-NET patients without second malignancies fared better than those with one or more of them.CONCLUSION:The number of detected GEP-NET increased about 5-fold in Germany between 1976 and2006.At the same time,their anatomic distribution changed,and the survival of GEP-NET patients improved significantly.Second malignancies are common and influence the overall survival of GEP-NET patients.Thus,GEP-NET
基金support from the Department of Metallurgical, Materials and Biomedical Engineering, University of Texas at El Pasosupport of the Key Research Program of Frontier Science, CAS (QYZDJ-SSW-JSC031-02)
文摘We elucidate here the process-structure-property relationships in three-dimensional(3 D) implantable titanium alloy biomaterials processed by electron beam melting(EBM) that is based on the principle of additive manufacturing. The conventional methods for processing of biomedical devices including freeze casting and sintering are limited because of the difficulties in adaptation at the host site and difference in the micro/macrostructure, mechanical, and physical properties with the host tissue. In this regard, EBM has a unique advantage of processing patient-specific complex designs, which can be either obtained from the computed tomography(CT) scan of the defect site or through a computeraided design(CAD) program. This review introduces and summarizes the evolution and underlying reasons that have motivated 3 D printing of scaffolds for tissue regeneration.The overview comprises of two parts for obtaining ultimate functionalities. The first part focuses on obtaining the ultimate functionalities in terms of mechanical properties of 3 D titanium alloy scaffolds fabricated by EBM with different characteristics based on design, unit cell, processing parameters, scan speed, porosity, and heat treatment. The second part focuses on the advancement of enhancing biological responses of these 3 D scaffolds and the influence of surface modification on cell-material interactions. The overview concludes with a discussion on the clinical trials of these 3 D porous scaffolds illustrating their potential in meeting the current needs of the biomedical industry.
基金the Fundamental Research Grant Scheme,Malaysia[FRGS/1/2015/SG05/UNIM/03/1]the Ministry of Science and Technology,Malaysia[MOSTI02-02-12-SF0256]+1 种基金the Prototype Research Grant Scheme,Malaysia[PRGS/2/2015/SG05/UNIM/03/1]International Cooperation Seeds Funding of Nanjing Agricultural University(Grant number:2018-AH-04).
文摘Microalgae has been consumed in human diet for thousands of years.It is an under-exploited crop for production of dietary foods.Microalgae cultivation does not compete with land and resources required for traditional crops and has a superior yield compared to terrestrial crops.Its high protein content has exhibited a huge potential to meet the dietary requirements of growing population.Apart from being a source of protein,presence of various bio-active components in microalgae provide an added health benefit.This review describes various microalgal sources of proteins and other bio-active components.One of the heavily studied group of bio-active components are pigments due to their anticarcenogenic,antioxidative and antihypertensive properties.Compared to various plant and floral species,microalgae contain higher amounts of pigments.Microalgal derived proteins have complete Essential Amino Acids(EAA)profiles and their protein content is higher than conventional sources such as meat,poultry and dairy products.However,microalgal based functional foods have not flooded the market.The lack of awareness coupled with scarce incentives for producers result in under-exploitation of microalgal potential.Application of microalgal derived components as dietary and nutraceutical supplements is discussed comprehensively.
文摘AIM: To critically appraise the published randomized, controlled trials on the prophylactic effectiveness of the non-steroidal anti-inflammatory drugs(NSAIDs), in reducing the risk of post-endoscopic retrograde cholangiopancreatography(ERCP) pancreatitis. METHODS: A systematic literature search(MEDLINE, Embase and the Cochrane Library, from inception of the databases until May 2015) was conducted to identify randomized, clinical trials investigating the role of NSAIDs in reducing the risk of post-ERCP pancreatitis. Random effects model of the meta-analysis was carried out, and results were presented as odds ratios(OR) with corresponding 95%CI.RESULTS: Thirteen randomized controlled trials on 3378 patients were included in the final meta-analysis. There were 1718 patients in the NSAIDs group and 1660 patients in non-NSAIDs group undergoing ERCP. The use of NSAIDs(through rectal route or intramuscular route) was associated with the reduced risk of post-ERCP pancreatitis [OR, 0.52(0.38-0.72), P = 0.0001]. The use of pre-procedure NSAIDs was effective in reducing approximately 48% incidence of post-ERCP pancreatitis, number needed to treat were 16 with absolute risk reduction of 0.05. But the risk of post-ERCP pancreattis was reduced by 55% if NSAIDs were administered after procedure. Similarly, diclofenac was more effective(55%) prophylactic agent compared to indomethacin(41%).CONCLUSION: NSAIDs seem to have clinically proven advantage of reducing the risk of post-ERCP pancreatitis.
基金supported in part by the Ministry of Science and Technology Project(2017YFC1104900 and 2016YFC1102601)the National Natural Science Foundation of China(51271182 and 51631007)+2 种基金Chinese Academy of Sciences Project(QYZDJ-SSW-JSC031)the Department of Metallurgical,Materials and Biomedical Engineering(Nune KC and Misra RDK)the Office of Research and Sponsored Projects(Correa-Rodriguez VL and Murr LE)at the University of Texas at El Paso
文摘In this study we describe the fabrication of a variety of open-cellular titanium alloy(Ti-6 Al-4 V) implants,both reticular mesh and foam structures, using electron beam melting(EBM). These structures allow for the elimination of stress shielding by adjusting the porosity(or density) to produce an elastic modulus(or stiffness) to match that of both soft(trabecular) and hard(cortical) bone, as well as allowing for bone cell ingrowth, increased cell density, and all-matrix interactions; the latter involving the interplay between bone morphogenetic protein(BMP-2) and osteoblast functions. The early formation and characterization of elementary vascular structures in an aqueous hydrogel matrix are illustrated.Preliminary results for both animal(sheep) and human trials for a number of EBM-fabricated, and often patient-specific Tialloy implants are also presented and summarized. The results, while preliminary, support the concept and development of successful, porous, engineered "living" implants.
文摘Rice sheath blight disease (ShB), caused by Rhizoctonia solani, gives rise to significant grain yield losses. The present study evaluated the efficacy of Integral, the commercial liquid formulation of Bacillus subtilis strain MBI 600, against rice ShB and for plant growth promotion. In greenhouse studies, four log concentrations of Integral (from 2.2×10^6 to 2.2×10^9 cfu/mL) were used as seed treatment (ST). After 25 d, seedlings were dipped (SD) into Integral prior to transplanting. At 30 d after transplanting (DAT), leaf sheaths were inoculated with immature sclerotia of the pathogen. At 45 DAT, a foliar spray (FS) with Integral was applied to some treatments. The fungicide control was 50% carbendazim at 1.0 g/L, and a nontreated control was also included. Overall, there were 10 treatments, each with five replications. ShB severity was rated at 52 DAT, and seedling height and number of tillers per plant were rated at 60 DAT. In 2009, two field trials evaluated Integral at 2.2×10^8 and 2.2×10^9 cfu/mL. Integral was applied as ST, and seedlings were produced in a nursery bed. After 32 d, seedlings were treated with Integral as SD and transplanted into 10 m^2 blocks. Foliar sprays were given at 45 and 60 DAT. There were seven treatments, each with eight replications arranged as a factorial randomized complete block design. At 20 DAT, the plots were broadcast inoculated with R. solani produced on rice grains. Seedling height before transplanting, ShB severity at 90 DAT, and grain yield at harvest were recorded. Integral at 2.2×10^9 cfu/mL provided significant increase of seedling heights over other treatments under greenhouse conditions. The Integral treatments of ST + SD + FS at 2.2×10^9 cfu/mL significantly suppressed ShB over other treatments. In field studies, Integral provided significant increase of seedling height in nursery, and number of tillers per plant, compared with the control. ShB severity was significantly suppressed with higher concentrations of Integral compared t
文摘Background The natural history of the profile and development of the miscellaneous complications. iver cirrhosis in China has not been we complications of liver cirrhosis as we understood. This study aimed to elucidate as the mortality of those cirrhotics with Methods We assembled data from the clinical characteristics, especially from the profile complications of cirrhosis on admission, and collected information by telephone or interview with patients and/or their family members in clinic to evaluate the development of complications in 920 patients enrolled in a prospective non-randomized cohort study, and followed up from June 2006 to October 2010. Mortality was calculated using Kaplan-Meier analysis and Cox regress analysis. We employed both of the Child-Pugh scoring system and model for end-stage liver disease (MELD) scoring system to compare with the accordance and veracity between liver function and the long-term outcome. Results On admission, only 7.4% patients had no complications, 44.5% patients with one complication (ascites, esophageal/gastric varices or hepatocellular carcinoma), 33.8% patients with two coexisting complications, and 7.5% patients had complications concurrently with ascites, esophageal/gastric varices and hepatocellular carcinoma. During the follow-up (mean follow-up time was 17 months, ranging from 1.0 to 52.2 months) of all the patients, 37.5% patients survived without new complications, 62.5% patients had new complications, and the overall mortality was 53.9%. Patients with one or more complications had higher mortality (total mortality, 1-year or 3-year mortality) and shorter mean survival time than those without any complication; the major cause of mortality of these cirrhotic patients was hepatocellular carcinoma (59%). Evaluated with the Child-Pugh score system, the total mortality in those with the scores more than 12 (class C) was 71.4%, the 1-year and 3-year mortalities were 57.1% and 71.4% respectively; while evaluated with the MELD scoring system, th
文摘AIM:To evaluate the accuracy of endoscopic ultrasound (EUS), EUS-fine needle aspiration (FNA) in evaluating mediastinal lymphadenopathy. METHODS:Only EUS and EUS-FNA studies confirmed by surgery or with appropriate follow-up were selected. Articles were searched in Medline, Pubmed, and Cochrane control trial registry. Only studies from which a 2 × 2 table could be constructed for true positive, false negative, false positive and true negative values were included. Two reviewers independently searched and extracted data. The differences were resolved by mutual agreement. Meta-analysis for the accuracy of EUS was analyzed by calculating pooled estimates of sensitivity, specificity, likelihood ratios, and diagnostic odds ratios. Pooling was conducted by both Mantel-Haenszel method (fixed effects model) and DerSimonian Laird method (random effects model). The heterogeneity of studies was tested using Cochran’s Q test based upon inverse variance weights. RESULTS:Data was extracted from 76 studies (n = 9310) which met the inclusion criteria. Of these, 44 studies used EUS alone and 32 studies used EUS-FNA. FNA improved the sensitivity of EUS from 84.7% (95% CI:82.9-86.4) to 88.0% (95% CI:85.8-90.0). With FNA, the specificity of EUS improved from 84.6% (95% CI:83.2-85.9) to 96.4% (95% CI:95.3-97.4). The P forchi-squared heterogeneity for all the pooled accuracy estimates was > 0.10. CONCLUSION:EUS is highly sensitive and specific for the evaluation of mediastinal lymphadenopathy and FNA substantially improves this. EUS with FNA should be the diagnostic test of choice for evaluating mediastinal lymphadenopathy.
文摘The rapid consumption of fossil fuel and increased environmental damage caused by it have given a strong impetus to the growth and development of fuelefficient vehicles. Hybrid electric vehicles (HEVs) have evolved from their inchoate state and are proving to be a promising solution to the serious existential problem posed to the planet earth. Not only do HEVs provide better fuel economy and lower emissions satisfying environmental legislations, but also they dampen the effect of rising fuel prices on consumers. HEVs combine the drive powers of an internal combustion engine and an electrical machine. The main components of HEVs are energy storage system, motor, bidirectional converter and maximum power point trackers (MPPT, in case of solar-powered HEVs). The performance of HEVs greatly depends on these components and its architecture. This paper presents an extensive review on essential components used in HEVs such as their architectures with advantages and disadvantages, choice of bidirectional converter to obtain high efficiency, combining ultracapacitor with battery to extend the battery life, traction motors’ role and their suitability for a particular application. Inclusion of photovoltaic cell in HEVs is a fairly new concept and has been discussed in detail. Various MPPT techniques used for solar-driven HEVs are also discussed in this paper with their suitability.