Multiple Omicron sub-lineages have emerged,with Omicron XBB and XBB.1.5 subvariants becoming the dominant variants globally at the time of this study.The key feature of new variants is their ability to escape humoral ...Multiple Omicron sub-lineages have emerged,with Omicron XBB and XBB.1.5 subvariants becoming the dominant variants globally at the time of this study.The key feature of new variants is their ability to escape humoral immunity despite the fact that there are limited genetic changes from their preceding variants.This raises the question of whether Omicron should be regarded as a separate serotype from viruses serologically clustered with the ancestral severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)virus.Here,we present cross-neutralization data based on a pseudovirus neutralization test using convalescent sera from naïve individuals who had recovered from primary infection by SARS-CoV-1 and SARS-CoV-2 strains/variants including the ancestral virus and variants Beta,Delta,Omicron BA.1,Omicron BA.2 and Omicron BA.5.The results revealed no significant cross-neutralization in any of the three-way testing for SARS-CoV-1,ancestral SARS-CoV-2 and SARS-CoV-2 Omicron subvariants.The data argue for the assignment of three distinct serotypes for the currently known human-infecting SARS-related coronaviruses.展开更多
Biomization provides an important way to assign pollen taxa to biomes and to simulate palaeo-vegetation patterns, so that pollen data can be mapped to reconstruct biogeography and climate. The authors have tested the ...Biomization provides an important way to assign pollen taxa to biomes and to simulate palaeo-vegetation patterns, so that pollen data can be mapped to reconstruct biogeography and climate. The authors have tested the applicability of this procedure to assign modern pollen surface samples from China to biomes. The procedure successfully delineated the major vegetation types of China. When the same procedure was applied to 6 ka B.P. fossil pollen samples, the reconstructions showed that the forest zones were systematically shifted northwards ca. 300\500 km beyond their present northern limits in eastern China; the area of desert and steppe vegetation was reduced compared to the present in northwestern China; the area of tundra was reduced largely on the Tibetan Plateau. This research is a contribution to the project of BIOME 6000 in Pacific-Asian regions.展开更多
Internal hernia of the broad ligament is rare. Computerized tomography is the key tool of the diagnosis. The treatment is surgical and takes advantage of the use of laparoscopy. We report a case of internal hernia of ...Internal hernia of the broad ligament is rare. Computerized tomography is the key tool of the diagnosis. The treatment is surgical and takes advantage of the use of laparoscopy. We report a case of internal hernia of right broad ligament suspected on computerized tomography and treated by laparoscopy. The following was uneventful.展开更多
In the frame of the ZeuS-Ill project, a model study was started on evaluation the area-specific resistances （ASRs） of various layers being used in SOFC stacks. It is well known that stack performance not only depend...In the frame of the ZeuS-Ill project, a model study was started on evaluation the area-specific resistances （ASRs） of various layers being used in SOFC stacks. It is well known that stack performance not only depends on cell resistance but also on the electrical conductivity of the various applied contact and protective layers. Various layers have been tested under simulated SOFC conditions, and results have shown that the lowest ASR value, about 3 mΩ.cm2, was obtained for an LSM （2） contact layer. A significantly higher resistance was found for the combined contact and protective layer LCC10-Mn3O4, being around 37 mΩ.cm2 Related to the various tests, the total ASR of an F-design stack, developed by Forschungszentrum Jiilich, under ideal conditions can be estimated. In this case the ASR value was calculated as the sum of that of the LCC10-Mn3O4 layer and the formed oxide scale due to oxidation of Crofer22APU. Contacting resistance at the anode side was considered negligible. When differences in the ASR values occurred when compared with that from current-voltage measurements performed with real SOFC stacks, this can be explained by the limited contact area between interconnect and cathode. These results can be used to model the influence of various applied layers and different geometric contact areas on the overall ASR as determined from performance measurements with SOFC stacks.展开更多
We have given design of a very small residual dispersion fiber system consisting of a small dispersion fiber (SDF) with flat modal field and a corresponding dual core coaxial dispersion compensating fiber (DCF).
A series of lithium metasilicate （Li2SiO3） powder materials has been successfully synthesized by the microwave-assisted hydrothermal route using lithium hydroxide and tetraethyl-orthosilicate-derived sol precursors....A series of lithium metasilicate （Li2SiO3） powder materials has been successfully synthesized by the microwave-assisted hydrothermal route using lithium hydroxide and tetraethyl-orthosilicate-derived sol precursors. Ceramic powders were obtained under hydrothermal conditions of autogenous pressure in the presence of a nonionic surfactant. The production of pure and well-crystallized Li2 SiO3 using very short reaction times at low temperatures was shown by X-ray diffraction, scanning electron microscopy, and N2 adsorption-desorption analyses. Synthesized Li2SiO3 particles were nanocrystalline and exhibited different morphologies and specific surface areas depending on the synthesis conditions. Additionally, the capability of selected Li2SiO3 samples to absorb H20 and CO2 was evaluated via thermogravimet- ric analyses by varying the temperature, carrier gas, and water vapor concentration. Li2SiO3 particles exhibited interesting textural and morphological characteristics that make them suitable for use as a CO2 absorbent and which suggest that they also have the potential to be used in other applications.展开更多
BACKGROUND: The majority of patients undergoing surgical treatment for ST- elevation myocardial infarction receive antifibrinolytic therapy to limit blood loss. This approach appears counterintuitive to the accepted m...BACKGROUND: The majority of patients undergoing surgical treatment for ST- elevation myocardial infarction receive antifibrinolytic therapy to limit blood loss. This approach appears counterintuitive to the accepted medical treatment of the same condition- namely, fibrinolysis to limit thrombosis. Despite this concern, no independent, large- scale safety assessment has been undertaken. METHODS: In this observational study involving 4374 patients undergoing revascularization, we prospectively assessed three agents(aprotinin [1295 patients], aminocaproic acid [883], and tranexamic acid [822]) as compared with no agent(1374 patients) with regard to serious outcomes by propensity and multivariable methods.(Although aprotinin is a serine protease inhibitor, here we use the term antifibrinolytic therapy to include all three agents.) RESULTS: In propensity- adjusted, multivariable logistic regression(C- index, 0.72), use of aprotinin was associated with a doubling in the risk of renal failure requiring dialysis among patients undergoing complex coronary- artery surgery(odds ratio, 2.59; 95 percent confidence interval, 1.36 to 4.95) or primary surgery(odds ratio, 2.34; 95 percent confidence interval, 1.27 to 4.31). Similarly, use of aprotinin in the latter group was associated with a 55 percent increase in the risk of myocardial infarction or heart failure(P< 0.001) and a 181 percent increase in the risk of stroke or encephalopathy(P=0.001). Neither aminocaproic acid nor tranexamic acid was associated with an increased risk of renal, cardiac, or cerebral events. Adjustment according to propensity score for the use of any one of the three agents as compared with no agent yielded nearly identical findings. All the agents reduced blood loss. CONCLUSIONS: The association between aprotinin and serious end- organ damage indicates that continued use is not prudent. In contrast, the less expensive generic medications aminocaproic acid and tranexamic acid are safe alternatives.展开更多
Objective: To determine the prevalence of GNRH receptor (GNRHR) gene mutations in a large cohort of patients with idiopathic hypogonadotropic hypogonadism (IHH). Design: Molecular analysis and genotype/phenotype corre...Objective: To determine the prevalence of GNRH receptor (GNRHR) gene mutations in a large cohort of patients with idiopathic hypogonadotropic hypogonadism (IHH). Design: Molecular analysis and genotype/phenotype correlations. Setting: University molecular reproductive endocrinology laboratory. Patient(s): North American and Turkish patients with IHH. Intervention(s): DNA from 185 IHH patients were subjected to denaturing gradient gel electrophoresis for exons and splice junctions of the GNRHR gene. Variant fragments were sequenced. Main Outcome Measure(s): GNRHR mutations were characterized and compared with the phenotype. The prevalence of GNRHR mutations was also determined. Result(s): Three of 185 (1.6%; confidence interval [CI] 0.3%-4.7%) total IHH patients demonstrated compound heterozygous GNRHR mutations. All three were identified from a cohort of 85 normosmic patients (3.5%, CI 0.73%-7.5%), and none were demonstrated in hyposmic or anosmic IHH patients. GNRHR mutations were identified in 1 of 15 (6.7%; CI 0.2%-32.0%)-families with at least two affected siblings, and in 2 of 18 (11.1%; CI 1.4%-34.7%) normosmic females. None were found in presumably autosomal dominant families. Conclusion(s): GNRHR mutations account for approximately 3.5%of all normosmic and 7%-11%of presumed autosomal recessive IHH, suggesting that additional genes play an important role in normal puberty. We believe this to be the largest GNRHR gene mutation analysis performed to date in a population of IHH patients.展开更多
In the RAte Control versus Electrical cardioversion for persistent atrial fibrillation(RACE) study, 522 patients were randomized to either rate or rhythm control therapy. Lone atrial fibrillation(AF) was present in 89...In the RAte Control versus Electrical cardioversion for persistent atrial fibrillation(RACE) study, 522 patients were randomized to either rate or rhythm control therapy. Lone atrial fibrillation(AF) was present in 89 patients. Demographics, cardiovascular mortality and morbidity, and quality of life were compared between patients with lone AF and those with underlying structural heart disease. Patients with lone AF were significantly younger(65±10 vs 69±8 years) and had fewer complaints of fatigue(p=0.01) and dyspnea(p=0.005). With lone AF, quality-of-life scoreswere higher on almost all 8 Medical Outcomes Study Short-Form health survey questionnaire subscales, and comparable to healthy, age-and gender-matched controls. Mean follow-up was 2.3±0.6 years. Cardiovascular end points occurred in 9 patients with lone AF(10%),consisting of death(all bleedings) 3%, thromboembolic complications in 3%, nonfatal bleeding in 2%, and pacemaker implantation in 2%, but no heart failure and severe adverse effects due to antiarrhythmic drugs occurred. End points occurred in 95 patients(22%) with underlying diseases. Heart failure and severe adverse effects from drugs did not occur in patients with lone AF in this study. Despite the absence of demonstrable cardiovascular and cerebrovascular disease, lone AF is associated with bleeding and thromboembolism.展开更多
Purpose To describe the characteristics and outcomes of patients with cytomega lovirus (CMV) retinitis in the absence of human immunodeficiency virus (HIV) inf ection. Design Retrospective cohort study. Methods Consec...Purpose To describe the characteristics and outcomes of patients with cytomega lovirus (CMV) retinitis in the absence of human immunodeficiency virus (HIV) inf ection. Design Retrospective cohort study. Methods Consecutive patients with CMV retinitis in the absence of HIV infection were identified at a university hospi tal. Demographic and clinical characteristics were noted at the time of CMV reti nitis. Outcomes were determined retrospectively. Main outcome measures were rate s of second eye involvement, vision loss, rhegmatogenous retinal detachment (RD) , immune recovery uveitis, progression of retinitis, and mortality. Results The clinical characteristics of CMV retinitis in 18 patients (30 eyes) without HIV i nfection diagnosed between January 1, 1984, and April 13, 2003, were similar to those of patients with HIV infection. The incidences of visual loss to the level s of 20/50 or worse and of 20/200 or worse were 17%per eye-year and 14%per ey e-year, respectively. The observed incidence of RD was 3.7%per eye-year, and the mortality rate was 23%per person-year. Following reduction of immunosuppre ssion, 10 patients (56%) who discontinued anti-CMV therapy remained free of re tinitis progression. The incidence of immune recovery uveitis was 13%per person year. Conclusions In our series, CMV retinitis in patients without HIV infectio n had a clinical course similar to that in patients with AIDS treated with highl y active antiretroviral therapy (HAART), except the incidence of RD was lower for patients without AIDS. A substantial number of patients no longer re quired long-term anti-CMV therapy after adjustment of immunomodulatory therapy .展开更多
Objectives The object of this study was to determine the effect of pre -treatm ent with clopidogrel in patients undergoing elective stent implantation. Backgro und The treatment of patients with adenosine diphosphate ...Objectives The object of this study was to determine the effect of pre -treatm ent with clopidogrel in patients undergoing elective stent implantation. Backgro und The treatment of patients with adenosine diphosphate receptor blockers after percutaneous coronary intervention (PCI) with stent implantation has been shown to decrease the incidence of subacute stent thrombosis. Furthermore, non-ra-n domized studies on pre-treatment with clopidogrel among patients undergoing ste nt implantation have suggested a reduction in myocardial damage and clinical eve nts. The effect of pre-treatment with clopidogrel has been studied in only a fe w randomized trials. Methods In a randomized trial, three days of pre-treatment with clopidogrel was compared with standard post-procedural treatment in 203 p atients undergoing elective stent implantation. The primary end point was a rise in troponin I or creatine kinase-MB fraction (CKMB) serum levels at 6 to 8 and 16 to 24 h after PCI. Secondary end points were death, stroke, myocardial infar ction, coronary bypass grafting, repeated PCI, and subacute stent thrombosis at one and six months after PCI. Results No difference was found between non-pre- treated and pre-treated patients in the postprocedural elevation of troponin I (42<<43.3%>> vs. 48 <<51.1%>>, respectively, p=0.31) or CK-MB (6 <<6.3%>> vs. 7 <<7 .4%>>, respectively, p=0.78). Adjustment for possible confounding factors did no t change these findings. Patient follow-up at one and six months showed no sign ificant difference between the treatment groups in death, stroke, myocardial inf arction, coronary artery bypass grafting, repeated PCI, or subacute stent thromb osis. Conclusions In this randomized study, no beneficial effect of pre-treatme nt with clopidogrel on post-procedural elevation of troponin I and CK-MB or on clinical events after one and sixth months could be demonstrated. The study sug gests that among patients with stable coronary syndromes in whom coronary stent implantation is planned, pre-trea-tment may n展开更多
Aims:The mucopolysaccharidoses(MPS)are a heterogeneous group of rare disorders characterised by accumulation of glycosaminoglycans within multiple organ systems.This study aimed to determine the prevalence and severit...Aims:The mucopolysaccharidoses(MPS)are a heterogeneous group of rare disorders characterised by accumulation of glycosaminoglycans within multiple organ systems.This study aimed to determine the prevalence and severity of ocular complications in patients with MPS.Methods:Clinical ophthalmic features and electrodiagnostic results of 50 patients with a diagnosis of MPS were retrospectively reviewed.Results:A total of 79% of MPS IH patients had a visual acuity of less than 6/12 equivalent in their better eye,compared to 44% of MPS IH/S and 25% of MPS VI patients.In total,16% of MPS IH and 25% of MPS IH/S had severe corneal opacification,compared to 38% of MPS VI patients.16% of MPS IH patients had optic atrophy;21% of MPS VI patients had mild disc swelling,29% had markedly swollen discs,and 14% had optic atrophy.One patient with MPS IH,one with MPS IH/S and six with MPS VI had ocular hypertension.One MPS VI patient had glaucoma that required topical therapy.Nine patients with MPS IH had electrodiagnostic evidence of retinopathy,as did one MPS VI patient.Conclusions:Ocular complications causing significant reduction in vision are common in MPS.The majority of MPS I and MPS VI patients have corneal opacification,which can lead to difficulties in diagnosis and monitoring of glaucoma,optic disc changes,and retinopathy.展开更多
The relationship between process and form has been at the core of research in fluvial geomorphology. Form-process relationships of a natural river basin are strongly influenced by its hydrologic and sedimentologic pro...The relationship between process and form has been at the core of research in fluvial geomorphology. Form-process relationships of a natural river basin are strongly influenced by its hydrologic and sedimentologic processes as basin morphometric properties of length, shape, and relief, change in response to various hydrologic stimuli from the environment, but usually in line with well established laws. In the four fiver basins （Orashi, Otamiri, Sombreiro, New Calabar） examined in this study, however, empirical evidence does not conform neatly with theoretical postulates. Remarkable variations are noted in the molphometric properties of the catchments, when compared with established morphometric laws. The most varied in conformity are the Orashi and New Calabar basins, although the Sombreiro and Otamiri catchments also show some level of variation. Prime explanation for the morphometric and topographic non-conformity is caused by the nature of surficial material and the profoundly shallow relief of much of the study area, especially the alluvial flood and deltaic plains to the south and south-west of the study area.展开更多
Inflammatory bowel disease is rare in the Chinese population, which may result in limited support, misinformation, and unalleviated fears and adversely affect quality of life (QOL). This study compared the inflammator...Inflammatory bowel disease is rare in the Chinese population, which may result in limited support, misinformation, and unalleviated fears and adversely affect quality of life (QOL). This study compared the inflammatory bowel disease (IBD) related knowledge, QOL, and use of complementary and alternative medicines and therapies (CAMT) in two contrasting IBD populations. Chinese and Caucasian IBD patients completed a questionnaire on IBD knowledge and CAMT usage. QOL was evaluated using the validated Inflammatory Bowel Disease Questionnaire. One hundred sixty two IBD patients were recruited, 81 Chinese and 81 Caucasian. The IBD knowledge score was higher in Caucasian than in Chinese IBD patients (median difference, 6.5; P = 0.001) and was independent of education and occupation. Twenty one percent of Chinese subjects incorrectly identified their IBD type (0%in the Caucasian group; P < 0.001). QOL was higher in the Chinese than the Caucasian group, but not significantly different after adjusting for disease activity. QOL was unassociated with IBD knowledge. The overall use of CAMT was similar in both groups (33%of Chinese and 37%of Caucasian patients) and similar for Crohn’s disease and ulcerative colitis. IBD related knowledge was inferior in Chinese compared to Caucasian IBD patients. Health related QOL is unlikely to be greatly influenced by disease related knowle dge or education. A high proportion of Chinese and Caucasian IBD patients uses CAMT.展开更多
Background: Previously reported pathological series suggest that cardiac malformations are universal in trisomy 18. We examined our experience of fetal echocardiography in trisomy 18 for comparison. Methods: Of 255 fe...Background: Previously reported pathological series suggest that cardiac malformations are universal in trisomy 18. We examined our experience of fetal echocardiography in trisomy 18 for comparison. Methods: Of 255 fetuses with trisomy 18 detected in our centre between January 1999 and June 2004, 174 were evaluated using fetal echocardiography. Our results were compared to four previous echocardiographic and four autopsy series, comprising 89 and 110 patients, respectively. Results: Of these 174 fetuses, 114 were examined between 10 and 14 weeks gestation and the remainder between 15 and 33 weeks. An increased nuchal translucency measurement was the reason for referral inmost of the early cases and extracardiac anomalies in the remainder. Images were non-diagnostic in 12 cases (7% ), all examined at < 15 weeks gestation. Abnormal cardiac findings were detected in 118 of the remaining 162 fetuses (73% ), including 15 with functional anomalies. The various heart malformations included ventricular septal defects, tetralogy of Fallot, left heart disease, and atrioventricular septal defects. In all series used for comparison, a similar diversity of disease was seen. In pathological series of trisomy 18, structural heart malformations were found in all cases, but some had lesions which would not be detectable echocardiographically in the fetus. Conclusion: Abnormal cardiac findings are detectable echocardiographically in the majority of cases of trisomy 18 examined during fetal life, but not in all. A wide spectrum of heart defects is seen. Diagnosis of heart malformations can be made reliably, even in the first trimester at the time of nuchal translucency measurement.展开更多
PURPOSE: Videoreflective dacryomeniscometry (VRD) for evaluation of marginal t ear film has not been performed in patients with watery eye or in a controlled s tudy. We used VRD to evaluate the height of the central m...PURPOSE: Videoreflective dacryomeniscometry (VRD) for evaluation of marginal t ear film has not been performed in patients with watery eye or in a controlled s tudy. We used VRD to evaluate the height of the central marginal lower lid tear film in normal adults and compared it with two watery-eye groups and a postoper ative dacryocystorhinostomy (DCR) group. DESIGN: Case-controlled interventional case series. METHODS: We evaluated with VRD 20 subjects with normal lacrimal dr ainage function, 21 patients with primary acquired nasolacrimal duct obstruction (PANDO), 28 patients with functional nasolacrimal duct obstruction (FNLDO), and a postoperative group of 14 patients derived from the previous two pathologic groups. Comparison between the four groups was performed to determine statisti cally significant differences between tear film height. RESULTS: PANDO and FNLDO groups were shown to have significantly greater median tear meniscus heights ([ TMH] PANDO: 620 μm, interquartile range [IQR] 453 μm; FNLDO: 731 μm, IQR 529 μm) than normal subjects (296 μm, IQR 214 μm; P< .001) and postoperative PAND O patients (265 μm, IQR 159 μm). There was no significant difference in TMH be tween PANDO and FNLDO groups preoperatively (P=.275). There was a reduction in m edian TMH postoperatively of 355 μm (P=.008) in PANDO and 360 μm (P=.068) in F NLDO. CONCLUSIONS: PANDO and FNLDO patients have similar preoperative TMH. In bo th these groups, TMH is significantly greater than in normal control subjects. L acrimal drainage surgery substantially reduces TMH as measured using VRD in PAND O.展开更多
基金supported in part by grants from the National Medical Research Council(COVID19RF-001,COVID19RF-003,COVID19RF-0008,COVID19RF-0014,COVID19RF-0018,COVID19RF3-0060,MOH-000535/MOH-OFYIRG19nov-0002 and MOH-000505-02)SingHealth Duke-NUS Academic Medicine COVID-19 Rapid Response Research Grant(AM/COV001/2020)+3 种基金Collaborative Research Fund(C2103-20GF)Wellcome COVID-19 Grant on Understanding the Biological Significance SARS-CoV-2 Variants(226120/Z/22/Z)National Institute of Health NIAID(R01AI163118 and 5U01AI151797)National Public Health COVID Program of the Government of Monaco.
文摘Multiple Omicron sub-lineages have emerged,with Omicron XBB and XBB.1.5 subvariants becoming the dominant variants globally at the time of this study.The key feature of new variants is their ability to escape humoral immunity despite the fact that there are limited genetic changes from their preceding variants.This raises the question of whether Omicron should be regarded as a separate serotype from viruses serologically clustered with the ancestral severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)virus.Here,we present cross-neutralization data based on a pseudovirus neutralization test using convalescent sera from naïve individuals who had recovered from primary infection by SARS-CoV-1 and SARS-CoV-2 strains/variants including the ancestral virus and variants Beta,Delta,Omicron BA.1,Omicron BA.2 and Omicron BA.5.The results revealed no significant cross-neutralization in any of the three-way testing for SARS-CoV-1,ancestral SARS-CoV-2 and SARS-CoV-2 Omicron subvariants.The data argue for the assignment of three distinct serotypes for the currently known human-infecting SARS-related coronaviruses.
文摘Biomization provides an important way to assign pollen taxa to biomes and to simulate palaeo-vegetation patterns, so that pollen data can be mapped to reconstruct biogeography and climate. The authors have tested the applicability of this procedure to assign modern pollen surface samples from China to biomes. The procedure successfully delineated the major vegetation types of China. When the same procedure was applied to 6 ka B.P. fossil pollen samples, the reconstructions showed that the forest zones were systematically shifted northwards ca. 300\500 km beyond their present northern limits in eastern China; the area of desert and steppe vegetation was reduced compared to the present in northwestern China; the area of tundra was reduced largely on the Tibetan Plateau. This research is a contribution to the project of BIOME 6000 in Pacific-Asian regions.
文摘Internal hernia of the broad ligament is rare. Computerized tomography is the key tool of the diagnosis. The treatment is surgical and takes advantage of the use of laparoscopy. We report a case of internal hernia of right broad ligament suspected on computerized tomography and treated by laparoscopy. The following was uneventful.
文摘In the frame of the ZeuS-Ill project, a model study was started on evaluation the area-specific resistances （ASRs） of various layers being used in SOFC stacks. It is well known that stack performance not only depends on cell resistance but also on the electrical conductivity of the various applied contact and protective layers. Various layers have been tested under simulated SOFC conditions, and results have shown that the lowest ASR value, about 3 mΩ.cm2, was obtained for an LSM （2） contact layer. A significantly higher resistance was found for the combined contact and protective layer LCC10-Mn3O4, being around 37 mΩ.cm2 Related to the various tests, the total ASR of an F-design stack, developed by Forschungszentrum Jiilich, under ideal conditions can be estimated. In this case the ASR value was calculated as the sum of that of the LCC10-Mn3O4 layer and the formed oxide scale due to oxidation of Crofer22APU. Contacting resistance at the anode side was considered negligible. When differences in the ASR values occurred when compared with that from current-voltage measurements performed with real SOFC stacks, this can be explained by the limited contact area between interconnect and cathode. These results can be used to model the influence of various applied layers and different geometric contact areas on the overall ASR as determined from performance measurements with SOFC stacks.
文摘We have given design of a very small residual dispersion fiber system consisting of a small dispersion fiber (SDF) with flat modal field and a corresponding dual core coaxial dispersion compensating fiber (DCF).
文摘A series of lithium metasilicate （Li2SiO3） powder materials has been successfully synthesized by the microwave-assisted hydrothermal route using lithium hydroxide and tetraethyl-orthosilicate-derived sol precursors. Ceramic powders were obtained under hydrothermal conditions of autogenous pressure in the presence of a nonionic surfactant. The production of pure and well-crystallized Li2 SiO3 using very short reaction times at low temperatures was shown by X-ray diffraction, scanning electron microscopy, and N2 adsorption-desorption analyses. Synthesized Li2SiO3 particles were nanocrystalline and exhibited different morphologies and specific surface areas depending on the synthesis conditions. Additionally, the capability of selected Li2SiO3 samples to absorb H20 and CO2 was evaluated via thermogravimet- ric analyses by varying the temperature, carrier gas, and water vapor concentration. Li2SiO3 particles exhibited interesting textural and morphological characteristics that make them suitable for use as a CO2 absorbent and which suggest that they also have the potential to be used in other applications.
文摘BACKGROUND: The majority of patients undergoing surgical treatment for ST- elevation myocardial infarction receive antifibrinolytic therapy to limit blood loss. This approach appears counterintuitive to the accepted medical treatment of the same condition- namely, fibrinolysis to limit thrombosis. Despite this concern, no independent, large- scale safety assessment has been undertaken. METHODS: In this observational study involving 4374 patients undergoing revascularization, we prospectively assessed three agents(aprotinin [1295 patients], aminocaproic acid [883], and tranexamic acid [822]) as compared with no agent(1374 patients) with regard to serious outcomes by propensity and multivariable methods.(Although aprotinin is a serine protease inhibitor, here we use the term antifibrinolytic therapy to include all three agents.) RESULTS: In propensity- adjusted, multivariable logistic regression(C- index, 0.72), use of aprotinin was associated with a doubling in the risk of renal failure requiring dialysis among patients undergoing complex coronary- artery surgery(odds ratio, 2.59; 95 percent confidence interval, 1.36 to 4.95) or primary surgery(odds ratio, 2.34; 95 percent confidence interval, 1.27 to 4.31). Similarly, use of aprotinin in the latter group was associated with a 55 percent increase in the risk of myocardial infarction or heart failure(P< 0.001) and a 181 percent increase in the risk of stroke or encephalopathy(P=0.001). Neither aminocaproic acid nor tranexamic acid was associated with an increased risk of renal, cardiac, or cerebral events. Adjustment according to propensity score for the use of any one of the three agents as compared with no agent yielded nearly identical findings. All the agents reduced blood loss. CONCLUSIONS: The association between aprotinin and serious end- organ damage indicates that continued use is not prudent. In contrast, the less expensive generic medications aminocaproic acid and tranexamic acid are safe alternatives.
文摘Objective: To determine the prevalence of GNRH receptor (GNRHR) gene mutations in a large cohort of patients with idiopathic hypogonadotropic hypogonadism (IHH). Design: Molecular analysis and genotype/phenotype correlations. Setting: University molecular reproductive endocrinology laboratory. Patient(s): North American and Turkish patients with IHH. Intervention(s): DNA from 185 IHH patients were subjected to denaturing gradient gel electrophoresis for exons and splice junctions of the GNRHR gene. Variant fragments were sequenced. Main Outcome Measure(s): GNRHR mutations were characterized and compared with the phenotype. The prevalence of GNRHR mutations was also determined. Result(s): Three of 185 (1.6%; confidence interval [CI] 0.3%-4.7%) total IHH patients demonstrated compound heterozygous GNRHR mutations. All three were identified from a cohort of 85 normosmic patients (3.5%, CI 0.73%-7.5%), and none were demonstrated in hyposmic or anosmic IHH patients. GNRHR mutations were identified in 1 of 15 (6.7%; CI 0.2%-32.0%)-families with at least two affected siblings, and in 2 of 18 (11.1%; CI 1.4%-34.7%) normosmic females. None were found in presumably autosomal dominant families. Conclusion(s): GNRHR mutations account for approximately 3.5%of all normosmic and 7%-11%of presumed autosomal recessive IHH, suggesting that additional genes play an important role in normal puberty. We believe this to be the largest GNRHR gene mutation analysis performed to date in a population of IHH patients.
文摘In the RAte Control versus Electrical cardioversion for persistent atrial fibrillation(RACE) study, 522 patients were randomized to either rate or rhythm control therapy. Lone atrial fibrillation(AF) was present in 89 patients. Demographics, cardiovascular mortality and morbidity, and quality of life were compared between patients with lone AF and those with underlying structural heart disease. Patients with lone AF were significantly younger(65±10 vs 69±8 years) and had fewer complaints of fatigue(p=0.01) and dyspnea(p=0.005). With lone AF, quality-of-life scoreswere higher on almost all 8 Medical Outcomes Study Short-Form health survey questionnaire subscales, and comparable to healthy, age-and gender-matched controls. Mean follow-up was 2.3±0.6 years. Cardiovascular end points occurred in 9 patients with lone AF(10%),consisting of death(all bleedings) 3%, thromboembolic complications in 3%, nonfatal bleeding in 2%, and pacemaker implantation in 2%, but no heart failure and severe adverse effects due to antiarrhythmic drugs occurred. End points occurred in 95 patients(22%) with underlying diseases. Heart failure and severe adverse effects from drugs did not occur in patients with lone AF in this study. Despite the absence of demonstrable cardiovascular and cerebrovascular disease, lone AF is associated with bleeding and thromboembolism.
文摘Purpose To describe the characteristics and outcomes of patients with cytomega lovirus (CMV) retinitis in the absence of human immunodeficiency virus (HIV) inf ection. Design Retrospective cohort study. Methods Consecutive patients with CMV retinitis in the absence of HIV infection were identified at a university hospi tal. Demographic and clinical characteristics were noted at the time of CMV reti nitis. Outcomes were determined retrospectively. Main outcome measures were rate s of second eye involvement, vision loss, rhegmatogenous retinal detachment (RD) , immune recovery uveitis, progression of retinitis, and mortality. Results The clinical characteristics of CMV retinitis in 18 patients (30 eyes) without HIV i nfection diagnosed between January 1, 1984, and April 13, 2003, were similar to those of patients with HIV infection. The incidences of visual loss to the level s of 20/50 or worse and of 20/200 or worse were 17%per eye-year and 14%per ey e-year, respectively. The observed incidence of RD was 3.7%per eye-year, and the mortality rate was 23%per person-year. Following reduction of immunosuppre ssion, 10 patients (56%) who discontinued anti-CMV therapy remained free of re tinitis progression. The incidence of immune recovery uveitis was 13%per person year. Conclusions In our series, CMV retinitis in patients without HIV infectio n had a clinical course similar to that in patients with AIDS treated with highl y active antiretroviral therapy (HAART), except the incidence of RD was lower for patients without AIDS. A substantial number of patients no longer re quired long-term anti-CMV therapy after adjustment of immunomodulatory therapy .
文摘Objectives The object of this study was to determine the effect of pre -treatm ent with clopidogrel in patients undergoing elective stent implantation. Backgro und The treatment of patients with adenosine diphosphate receptor blockers after percutaneous coronary intervention (PCI) with stent implantation has been shown to decrease the incidence of subacute stent thrombosis. Furthermore, non-ra-n domized studies on pre-treatment with clopidogrel among patients undergoing ste nt implantation have suggested a reduction in myocardial damage and clinical eve nts. The effect of pre-treatment with clopidogrel has been studied in only a fe w randomized trials. Methods In a randomized trial, three days of pre-treatment with clopidogrel was compared with standard post-procedural treatment in 203 p atients undergoing elective stent implantation. The primary end point was a rise in troponin I or creatine kinase-MB fraction (CKMB) serum levels at 6 to 8 and 16 to 24 h after PCI. Secondary end points were death, stroke, myocardial infar ction, coronary bypass grafting, repeated PCI, and subacute stent thrombosis at one and six months after PCI. Results No difference was found between non-pre- treated and pre-treated patients in the postprocedural elevation of troponin I (42<<43.3%>> vs. 48 <<51.1%>>, respectively, p=0.31) or CK-MB (6 <<6.3%>> vs. 7 <<7 .4%>>, respectively, p=0.78). Adjustment for possible confounding factors did no t change these findings. Patient follow-up at one and six months showed no sign ificant difference between the treatment groups in death, stroke, myocardial inf arction, coronary artery bypass grafting, repeated PCI, or subacute stent thromb osis. Conclusions In this randomized study, no beneficial effect of pre-treatme nt with clopidogrel on post-procedural elevation of troponin I and CK-MB or on clinical events after one and sixth months could be demonstrated. The study sug gests that among patients with stable coronary syndromes in whom coronary stent implantation is planned, pre-trea-tment may n
文摘Aims:The mucopolysaccharidoses(MPS)are a heterogeneous group of rare disorders characterised by accumulation of glycosaminoglycans within multiple organ systems.This study aimed to determine the prevalence and severity of ocular complications in patients with MPS.Methods:Clinical ophthalmic features and electrodiagnostic results of 50 patients with a diagnosis of MPS were retrospectively reviewed.Results:A total of 79% of MPS IH patients had a visual acuity of less than 6/12 equivalent in their better eye,compared to 44% of MPS IH/S and 25% of MPS VI patients.In total,16% of MPS IH and 25% of MPS IH/S had severe corneal opacification,compared to 38% of MPS VI patients.16% of MPS IH patients had optic atrophy;21% of MPS VI patients had mild disc swelling,29% had markedly swollen discs,and 14% had optic atrophy.One patient with MPS IH,one with MPS IH/S and six with MPS VI had ocular hypertension.One MPS VI patient had glaucoma that required topical therapy.Nine patients with MPS IH had electrodiagnostic evidence of retinopathy,as did one MPS VI patient.Conclusions:Ocular complications causing significant reduction in vision are common in MPS.The majority of MPS I and MPS VI patients have corneal opacification,which can lead to difficulties in diagnosis and monitoring of glaucoma,optic disc changes,and retinopathy.
文摘The relationship between process and form has been at the core of research in fluvial geomorphology. Form-process relationships of a natural river basin are strongly influenced by its hydrologic and sedimentologic processes as basin morphometric properties of length, shape, and relief, change in response to various hydrologic stimuli from the environment, but usually in line with well established laws. In the four fiver basins （Orashi, Otamiri, Sombreiro, New Calabar） examined in this study, however, empirical evidence does not conform neatly with theoretical postulates. Remarkable variations are noted in the molphometric properties of the catchments, when compared with established morphometric laws. The most varied in conformity are the Orashi and New Calabar basins, although the Sombreiro and Otamiri catchments also show some level of variation. Prime explanation for the morphometric and topographic non-conformity is caused by the nature of surficial material and the profoundly shallow relief of much of the study area, especially the alluvial flood and deltaic plains to the south and south-west of the study area.
文摘Inflammatory bowel disease is rare in the Chinese population, which may result in limited support, misinformation, and unalleviated fears and adversely affect quality of life (QOL). This study compared the inflammatory bowel disease (IBD) related knowledge, QOL, and use of complementary and alternative medicines and therapies (CAMT) in two contrasting IBD populations. Chinese and Caucasian IBD patients completed a questionnaire on IBD knowledge and CAMT usage. QOL was evaluated using the validated Inflammatory Bowel Disease Questionnaire. One hundred sixty two IBD patients were recruited, 81 Chinese and 81 Caucasian. The IBD knowledge score was higher in Caucasian than in Chinese IBD patients (median difference, 6.5; P = 0.001) and was independent of education and occupation. Twenty one percent of Chinese subjects incorrectly identified their IBD type (0%in the Caucasian group; P < 0.001). QOL was higher in the Chinese than the Caucasian group, but not significantly different after adjusting for disease activity. QOL was unassociated with IBD knowledge. The overall use of CAMT was similar in both groups (33%of Chinese and 37%of Caucasian patients) and similar for Crohn’s disease and ulcerative colitis. IBD related knowledge was inferior in Chinese compared to Caucasian IBD patients. Health related QOL is unlikely to be greatly influenced by disease related knowle dge or education. A high proportion of Chinese and Caucasian IBD patients uses CAMT.
文摘Background: Previously reported pathological series suggest that cardiac malformations are universal in trisomy 18. We examined our experience of fetal echocardiography in trisomy 18 for comparison. Methods: Of 255 fetuses with trisomy 18 detected in our centre between January 1999 and June 2004, 174 were evaluated using fetal echocardiography. Our results were compared to four previous echocardiographic and four autopsy series, comprising 89 and 110 patients, respectively. Results: Of these 174 fetuses, 114 were examined between 10 and 14 weeks gestation and the remainder between 15 and 33 weeks. An increased nuchal translucency measurement was the reason for referral inmost of the early cases and extracardiac anomalies in the remainder. Images were non-diagnostic in 12 cases (7% ), all examined at < 15 weeks gestation. Abnormal cardiac findings were detected in 118 of the remaining 162 fetuses (73% ), including 15 with functional anomalies. The various heart malformations included ventricular septal defects, tetralogy of Fallot, left heart disease, and atrioventricular septal defects. In all series used for comparison, a similar diversity of disease was seen. In pathological series of trisomy 18, structural heart malformations were found in all cases, but some had lesions which would not be detectable echocardiographically in the fetus. Conclusion: Abnormal cardiac findings are detectable echocardiographically in the majority of cases of trisomy 18 examined during fetal life, but not in all. A wide spectrum of heart defects is seen. Diagnosis of heart malformations can be made reliably, even in the first trimester at the time of nuchal translucency measurement.
文摘PURPOSE: Videoreflective dacryomeniscometry (VRD) for evaluation of marginal t ear film has not been performed in patients with watery eye or in a controlled s tudy. We used VRD to evaluate the height of the central marginal lower lid tear film in normal adults and compared it with two watery-eye groups and a postoper ative dacryocystorhinostomy (DCR) group. DESIGN: Case-controlled interventional case series. METHODS: We evaluated with VRD 20 subjects with normal lacrimal dr ainage function, 21 patients with primary acquired nasolacrimal duct obstruction (PANDO), 28 patients with functional nasolacrimal duct obstruction (FNLDO), and a postoperative group of 14 patients derived from the previous two pathologic groups. Comparison between the four groups was performed to determine statisti cally significant differences between tear film height. RESULTS: PANDO and FNLDO groups were shown to have significantly greater median tear meniscus heights ([ TMH] PANDO: 620 μm, interquartile range [IQR] 453 μm; FNLDO: 731 μm, IQR 529 μm) than normal subjects (296 μm, IQR 214 μm; P< .001) and postoperative PAND O patients (265 μm, IQR 159 μm). There was no significant difference in TMH be tween PANDO and FNLDO groups preoperatively (P=.275). There was a reduction in m edian TMH postoperatively of 355 μm (P=.008) in PANDO and 360 μm (P=.068) in F NLDO. CONCLUSIONS: PANDO and FNLDO patients have similar preoperative TMH. In bo th these groups, TMH is significantly greater than in normal control subjects. L acrimal drainage surgery substantially reduces TMH as measured using VRD in PAND O.
