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BCLC策略:预后预测和治疗推荐2022版更新 被引量:173
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作者 Reig M Forner A +16 位作者 Rimola J Ferrer-Fabrega J Burrel M Garcia-Criado A Kelley RK Galle PR Mazzaferro V salem R Sangro B Singal AG Vogel A Fuster J Ayuso C Bruix J 刘永凡(摘译) 崔笑(摘译) 耿小平(审校) 《肝胆外科杂志》 2022年第5期399-400,共2页
2018版BCLC预后和治疗推荐策略发布后,肝细胞癌(简称HCC)的研究又取得了重大进展。本次更新基于肝癌各领域的研究进展结果。重点关注影响策略的重要研究进展。虽然近年的研究结果成绩斐然,但将其引入为临床医生和研究者提供行动依据的... 2018版BCLC预后和治疗推荐策略发布后,肝细胞癌(简称HCC)的研究又取得了重大进展。本次更新基于肝癌各领域的研究进展结果。重点关注影响策略的重要研究进展。虽然近年的研究结果成绩斐然,但将其引入为临床医生和研究者提供行动依据的循证模型指南来说证据效力依然不够确切。本文对该问题进行分析,阐述了为HCC患者制定个体化治疗临床决策所需的批判性思维和专业知识。 展开更多
关键词 临床决策 个体化治疗 临床医生 肝细胞癌 证据效力 BCL 批判性思维 专业知识
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Inflammatory pathways of importance for management of inflammatory bowel disease 被引量:33
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作者 Jannie Pedersen Mehmet Coskun +2 位作者 Christoffer Soendergaard Mohammad salem Ole Haagen Nielsen 《World Journal of Gastroenterology》 SCIE CAS 2014年第1期64-77,共14页
Inflammatory bowel disease (IBD) is a group of chronic disorders of the gastrointestinal tract comprising Crohn&#x02019;s disease (CD) and ulcerative colitis (UC). Their etiologies are unknown, but they are charac... Inflammatory bowel disease (IBD) is a group of chronic disorders of the gastrointestinal tract comprising Crohn&#x02019;s disease (CD) and ulcerative colitis (UC). Their etiologies are unknown, but they are characterised by an imbalanced production of pro-inflammatory mediators, e.g., tumor necrosis factor (TNF)-&#x003b1;, as well as increased recruitment of leukocytes to the site of inflammation. Advantages in understanding the role of the inflammatory pathways in IBD and an inadequate response to conventional therapy in a large portion of patients, has over the last two decades lead to new therapies which includes the TNF inhibitors (TNFi), designed to target and neutralise the effect of TNF-&#x003b1;. TNFi have shown to be efficient in treating moderate to severe CD and UC. However, convenient alternative therapeutics targeting other immune pathways are needed for patients with IBD refractory to conventional therapy including TNFi. Indeed, several therapeutics are currently under development, and have shown success in clinical trials. These include antibodies targeting and neutralising interleukin-12/23, small pharmacologic Janus kinase inhibitors designed to block intracellular signaling of several pro-inflammatory cytokines, antibodies targeting integrins, and small anti-adhesion molecules that block adhesion between leukocytes and the intestinal vascular endothelium, reducing their infiltration into the inflamed mucosa. In this review we have elucidated the major signaling pathways of clinical importance for IBD therapy and highlighted the new promising therapies available. As stated in this paper several new treatment options are under development for the treatment of CD and UC, however, no drug fits all patients. Hence, optimisations of treatment regimens are warranted for the benefit of the patients either through biomarker establishment or other rationales to maximise the effect of the broad range of mode-of-actions of the present and future drugs in IBD. 展开更多
关键词 Anti-tumor necrosis factor Biologics Crohn’ s disease Pro-inflammatory cytokines Signaling pathways Treatment Ulcerative colitis
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An efficient enhanced k-means clustering algorithm 被引量:30
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作者 FAHIM A.M salem A.M +1 位作者 TORKEY F.A RAMADAN M.A 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第10期1626-1633,共8页
In k-means clustering, we are given a set of n data points in d-dimensional space R^d and an integer k and the problem is to determine a set of k points in R^d, called centers, so as to minimize the mean squared dista... In k-means clustering, we are given a set of n data points in d-dimensional space R^d and an integer k and the problem is to determine a set of k points in R^d, called centers, so as to minimize the mean squared distance from each data point to its nearest center. In this paper, we present a simple and efficient clustering algorithm based on the k-means algorithm, which we call enhanced k-means algorithm. This algorithm is easy to implement, requiring a simple data structure to keep some information in each iteration to be used in the next iteration. Our experimental results demonstrated that our scheme can improve the computational speed of the k-means algorithm by the magnitude in the total number of distance calculations and the overall time of computation. 展开更多
关键词 Clustering algorithms Cluster analysis k-means algorithm Data analysis
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三倍回波化学位移梯度回波成像与活体^1H-MRS对肝脏脂肪含量定量分析的对照研究 被引量:24
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作者 B.Guiu J.M.Petit +4 位作者 R.Loffroy D.Ben salem S.Aho D.Masson 范丽 《国际医学放射学杂志》 2009年第2期176-177,共2页
目的 以活体^1H-MRS作为参考标准,评价三倍回波梯度回波序列对肝脏脂肪含量的量化。方法 此前瞻畦研究经伦理委员会批准,且所有病人签署了书面知情同意书。37例2型糖尿病病人(男31例,女6例,平均年龄56岁)采用3.0 T MR设备先对... 目的 以活体^1H-MRS作为参考标准,评价三倍回波梯度回波序列对肝脏脂肪含量的量化。方法 此前瞻畦研究经伦理委员会批准,且所有病人签署了书面知情同意书。37例2型糖尿病病人(男31例,女6例,平均年龄56岁)采用3.0 T MR设备先对肝脏第VII段行单体素^1H-MRS,经T1和T2衰减的校正,通过4.7ppm(1ppm表示10^-6)水峰和1.3ppm甲基计算肝脏脂肪含量。 展开更多
关键词 ^1H-MRS 梯度回波成像 脂肪含量 肝脏 定量分析 化学位移 活体 梯度回波序列
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Disruption of the Sugar Transporters AtSWEET11 and AtSWEET12 Affects Vascular Development and Freezing Tolerance in Arabidopsis 被引量:21
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作者 Rozenn Le Hir Lara Spinner +13 位作者 Patrick A. W. Klemens Dipankar Chakraborti Federica de Marco Francoise Vilaine Nelly Wolff Remi Lemoine Benoit Porcheron Carine Gery Evelyne Teoule salem Chabout Gregory Mouille H. Ekkehard Neuhaus Sylvie Dinant Catherine Bellini 《Molecular Plant》 SCIE CAS CSCD 2015年第11期1687-1690,共4页
Dear Editor, In plants, the transport of sugars from the site of biosynthesis to the site of utilization or storage relies on sugar transporters located in different subcellular compartments and different vascular cel... Dear Editor, In plants, the transport of sugars from the site of biosynthesis to the site of utilization or storage relies on sugar transporters located in different subcellular compartments and different vascular cell types. The SWEET sugar transporter family is one such class and is represented by 17 members in Arabidopsis. AtSWEET1 was the first plant SWEET transporter to be characterized; it acts as a glucose uniporter in multiple systems (Chen et al., 2010). 展开更多
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Role of live microbial feed supplements with reference to anaerobic fungi in ruminant productivity: A review 被引量:19
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作者 Anil K Puniya Abdelfattah Z M salem +7 位作者 Sanjay Kumar Sumit S Dagar Gareth W Griffith Monica Puniya Sreenivas R Ravella Nikhil Kumar Tejpal Dhewa Ravinder Kumar 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第3期550-560,共11页
To keep the concept of a safe food supply to the consumers, animal feed industries world over are showing an increasing interest in the direct-fed microbials(DFM) for improved animal performance in terms of growth o... To keep the concept of a safe food supply to the consumers, animal feed industries world over are showing an increasing interest in the direct-fed microbials(DFM) for improved animal performance in terms of growth or productivity. This becomes all the more essential in a situation, where a number of the residues of antibiotics and/or other growth stimulants reach in milk and meat with a number of associated potential risks for the consumers. Hence, in the absence of growth stimulants, a positive manipulation of the rumen microbial ecosystem to enhance the feedstuff utilization for improved production efficiency by ruminants has become of much interest to the researchers and entrepreneurs. A few genera of live microbes(i.e., bacteria, fungi and yeasts in different types of formulations from paste to powder) are infrequently used as DFM for the domestic ruminants. These DFM products are live microbial feed supplements containing naturally occurring microbes in the rumen. Among different DFM possibilities, anaerobic rumen fungi(ARF) based additives have been found to improve ruminant productivity consistently during feeding trials. Administration of ARF during the few trials conducted, led to the increased weight gain, milk production, and total tract digestibility of feed components in ruminants. Anaerobic fungi in the rumen display very strong cell-wall degrading cellulolytic and xylanolytic activities through rhizoid development, resulting in the physical disruption of feed structure paving the way for bacterial action. Significant improvements in the fiber digestibility were found to coincide with increases in ARF in the rumen indicating their role. Most of the researches based on DFM have indicated a positive response in nutrient digestion and methane reducing potential during in vivo and/or in vitro supplementation of ARF as DFM. Therefore, DFM especially ARF will gain popularity but it is necessary that all the strains are thoroughly studied for their beneficial properties to have a confirmed ‘g 展开更多
关键词 anaerobic rumen fungi bacterial DFM direct-fed microbials PROBIOTICS RUMEN
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The effects of fermentation and adsorption using lactic acid bacteria culture broth on the feed quality of rice straw 被引量:16
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作者 LIU Jing-jing LIU Xiao-ping +5 位作者 REN Ji-wei ZHAO Hong-yan YUAN Xu-feng WANG Xiao-fen Abdelfattah Z M salem CUI Zong-jun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第3期503-513,共11页
To improve the nutritional value and the palatability of air-dried rice straw, culture broth of the lactic acid bacteria community SFC-2 was used to examine the effects of two different treatments, fermentation and ad... To improve the nutritional value and the palatability of air-dried rice straw, culture broth of the lactic acid bacteria community SFC-2 was used to examine the effects of two different treatments, fermentation and adsorption. Air-dried and chopped rice straw was treated with either fermentation for 30 d after adding 1.5 L nutrient solution(50 m L inocula L–1, 1.2×1012 CFU m L–1 inocula) kg–1 straw dry matter, or spraying a large amount of culture broth(1.5 L kg–1 straw dry matter, 1.5×1011 CFU m L–1 culture broth) on the straw and allowing it to adsorb for 30 min. The feed quality and aerobic stability of the resulting forage were examined. Both treatments improved the feed quality of rice straw, and adsorption was better than fermentation for preserving nutrients and improving digestibility, as evidenced by higher dry matter(DM) and crude protein(CP) concentrations, lower neutral detergent fiber(NDF), acid detergent fiber(ADF) and NH3-N concentrations, as well as higher lactic acid production and in vitro digestibility of DM(IVDMD). The aerobic stability of the adsorbed straw and the fermented straw was 392 and 480 h, respectively. After being exposed to air, chemical components and microbial community of the fermented straw were more stable than the adsorbed straw. 展开更多
关键词 ADSORPTION FERMENTATION lactic acid bacteria culture broth rice straw
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Radioembolization for the treatment of unresectable hepatocellular carcinoma:A clinical review 被引量:14
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作者 Saad M Ibrahim Robert J Lewandowski +6 位作者 Kent T Sato Vanessa L Gates Laura Kulik Mary F Mulcahy Robert K Ryu Reed A Omary Riad salem 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第11期1664-1669,共6页
Hepatocellular carcinoma(HCC)is the sixth most common cancer in the world.The majority of patients with HCC present with unresectable disease.These patients have historically had limited treatment options secondary to... Hepatocellular carcinoma(HCC)is the sixth most common cancer in the world.The majority of patients with HCC present with unresectable disease.These patients have historically had limited treatment options secondary to HCC demonstrating chemoresistance to the currently available systemic therapies.Additionally, normal liver parenchyma has shown intolerance to tumoricidal radiation doses,limiting the use of external beam radiation.Because of these limitations,novel percutaneous liver-directed therapies have emerged. The targeted infusion of radioactive microspheres (radioembolization)represents one such therapy. Radioembolization is a minimally invasive transcatheter therapy through which radioactive microspheres are infused into the hepatic arteries that supply tumor. Once infused,these microspheres traverse the hepatic vascular plexus and selectively implant within the tumor arterioles.Embedded within the arterioles, the 90Y impregnated microspheres emit high energy and low penetrating radiation doses selectively to the tumor.Radioembolization has recently shown promise for the treatment of patients with unresectable HCC. The objective of this review article is to highlight twocurrently available radioembolic devices(90Y,188Rh)and provide the reader with a recent review of the literature. 展开更多
关键词 RADIOEMBOLIZATION BRACHYTHERAPY Hepatocellular carcinoma Yttrium-90 RHENIUM-188
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Evaluation of extracts and essential oil from Callistemon viminalis leaves:Antibacterial and antioxidant activities,total phenolic and flavonoid contents 被引量:14
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作者 Mohamed ZM salem Hayssam M Ali +1 位作者 Nader A El-Shanhorey Ahmed Abdel-Megeed 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2013年第10期785-791,共7页
Objective:To investigate antioxidant and antibacterial activities of Callistemon viminalis(C.viminalis)leaves.Methods:The essential oil of C.viminalis leaves obtained by hydrodistillation was analyzed by GC/MS.Differe... Objective:To investigate antioxidant and antibacterial activities of Callistemon viminalis(C.viminalis)leaves.Methods:The essential oil of C.viminalis leaves obtained by hydrodistillation was analyzed by GC/MS.Different extracts were tested for total phenolic and flavonoid contents and in vitro antioxidant(DPPH assay)and antibacterial(agar disc diffusion and 96-well micro-plates methods)actives.Results:Fourteen components were identified in the essential oil,representing 98.94%of the total oil.The major components were 1,8-cineole(64.53%)andα-pinene(9.69%).Leaf essential oil exhibited the highest antioxidant activity of(88.60±1.51)%comparable to gallic acid,a standard compound[(80.00±2.12)%].Additionally,the biggest zone of inhibitions against the studied bacterial strains was observed by the essential oil when compared to the standard antibiotic(tetracycline).The crude methanol extract and ethyl acetate fraction had a significant antibacterial activity against the tested bacterial strains.Conclusions:It can be suggested that C.viminalis is a great potential source of antibacterial and antioxidant compounds useful for new antimicrobial drugs from the natural basis.The present study revealed that the essential oil as well as the methanol extracts and ethyl acetate fraction of C.viminalis leaves exhibited highly significant antibacterial activity against the tested bacterial strains. 展开更多
关键词 Callistemon viminalis Essential oil ANTIBACTERIAL ACTIVITY ANTIOXIDANT ACTIVITY PHENOLIC CONTENT Flavonoid CONTENT
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Evaluation of Protein Extraction Methods for Vitis vinifera Leaf and Root Proteome Analysis by Two-Dimensional Electrophoresis 被引量:12
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作者 Neila Jellouli Asma Ben salem +1 位作者 Abdelwahed Ghorbel Hatem Ben Jouira 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2010年第10期933-940,共8页
An efficient protein extraction method is crucial to ensure successful separation by two-dimensional electrophoresis (2-DE) for recalcitrant plant species, in particular for grapevine (Vitis vinifera L.). Trichlor... An efficient protein extraction method is crucial to ensure successful separation by two-dimensional electrophoresis (2-DE) for recalcitrant plant species, in particular for grapevine (Vitis vinifera L.). Trichloroacetic acid-acetone (TCA-acetone) and phenol extraction methods were evaluated for proteome analysis of leaves and roots from the Tunisian cultivar 'Razegui'. The phenol-based protocol proved to give a higher protein yield, a greater spot resolution, and a minimal streaking on 2-DE gels for both leaf and root tissues compared with the TCA-based protocol. Furthermore, the highest numbers of detected proteins on 2-DE gels were observed using the phenol extraction from leaves and roots as compared with TCA-acetone extraction. 展开更多
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Updates in the pathophysiological mechanisms of Parkinson's disease: Emerging role of bone marrow mesenchymal stem cells 被引量:9
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作者 Hanaa H Ahmed Ahmed M salem +5 位作者 Hazem M Atta Emad F Eskandar Abdel Razik H Farrag Mohamed A Ghazy Neveen A salem Hadeer A Aglan 《World Journal of Stem Cells》 SCIE CAS 2016年第3期106-117,共12页
AIM: To explore the approaches exerted by mesenchymal stem cells (MSCs) to improve Parkinson&#x02019;s disease (PD) pathophysiology.METHODS: MSCs were harvested from bone marrow of femoral bones of male rats, grow... AIM: To explore the approaches exerted by mesenchymal stem cells (MSCs) to improve Parkinson&#x02019;s disease (PD) pathophysiology.METHODS: MSCs were harvested from bone marrow of femoral bones of male rats, grown and propagated in culture. Twenty four ovariectomized animals were classified into 3 groups: Group (1) was control, Groups (2) and (3) were subcutaneously administered with rotenone for 14 d after one month of ovariectomy for induction of PD. Then, Group (2) was left untreated, while Group (3) was treated with single intravenous dose of bone marrow derived MSCs (BM-MSCs). SRY gene was assessed by PCR in brain tissue of the female rats. Serum transforming growth factor beta-1 (TGF-&#x003b2;1), monocyte chemoattractant protein-1 (MCP-1) and brain derived neurotrophic factor (BDNF) levels were assayed by ELISA. Brain dopamine DA level was assayed fluorometrically, while brain tyrosine hydroxylase (TH) and nestin gene expression were detected by semi-quantitative real time PCR. Brain survivin expression was determined by immunohistochemical procedure. Histopathological investigation of brain tissues was also done.RESULTS: BM-MSCs were able to home at the injured brains and elicited significant decrease in serum TGF-&#x003b2;1 (489.7 &#x000b1; 13.0 vs 691.2 &#x000b1; 8.0, P &#x0003c; 0.05) and MCP-1 (89.6 &#x000b1; 2.0 vs 112.1 &#x000b1; 1.9, P &#x0003c; 0.05) levels associated with significant increase in serum BDNF (3663 &#x000b1; 17.8 vs 2905 &#x000b1; 72.9, P &#x0003c; 0.05) and brain DA (874 &#x000b1; 15.0 vs 599 &#x000b1; 9.8, P &#x0003c; 0.05) levels as well as brain TH (1.18 &#x000b1; 0.004 vs 0.54 &#x000b1; 0.009, P &#x0003c; 0.05) and nestin (1.29 &#x000b1; 0.005 vs 0.67 &#x000b1; 0.006, P &#x0003c; 0.05) genes expression levels. In addition to, producing insignificant increase in the number of positive cells for survivin (293.2 &#x000b1; 15.9 vs 271.5 &#x000b1; 15.9, P &#x0003e; 0.05) expression. Finally, the brain sections showed intact histological structure of the striatum as a result of treat 展开更多
关键词 Parkinson’s disease PATHOPHYSIOLOGY Bone marrow derived mesenchymal stem cells ROTENONE Anti-inflammatory action OVARIECTOMY Anti-apoptotic effect Neurogenic potential
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Vascular calcification:When should we interfere in chronic kidney disease patients and how? 被引量:10
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作者 Usama Abdel Azim Sharaf El Din Mona Mansour salem Dina Ossama Abdulazim 《World Journal of Nephrology》 2016年第5期398-417,共20页
Chronic kidney disease (CKD) patients are endangered with the highest mortality rate compared to other chronic diseases. Cardiovascular events account for up to 60% of the fatalities. Cardiovascular calcifcations af... Chronic kidney disease (CKD) patients are endangered with the highest mortality rate compared to other chronic diseases. Cardiovascular events account for up to 60% of the fatalities. Cardiovascular calcifcations affect most of the CKD patients. Most of this calcification is related to disturbed renal phosphate handling. Fibroblast growth factor 23 and klotho defciency were incriminated in the pathogenesis of vascular calcification through different mechanisms including their effects on endothelium and arterial wall smooth muscle cells. In addition, deficient klotho gene expression, a constant feature of CKD, pro-motes vascular pathology and shares in progression of the CKD. The role of gut in the etio-pathogenesis of systemic infammation and vascular calcifcation is a newly discovered mechanism. This review will cover the medical history, prevalence, pathogenesis, clinical relevance, different tools used to diagnose, the ideal timing to prevent or to withhold the progression of vascular cal-cification and the different medications and medical procedures that can help to prolong the survival of CKD patients. 展开更多
关键词 Chronic kidney disease UREMIA Calcifcation SEVELAMER Calcific uremic arteriolopathy Fibroblast growth factor 23 KLOTHO Phosphate binders Kidney transplantation
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Clinical correlates of common corneal neovascular diseases: a literature review 被引量:10
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作者 Nizar Saleh Abdelfattah Mohamed Amgad +4 位作者 Amira A Zayed Hamdy salem Ahmed E Elkhanany Heba Hussein Nawal Abd El-Baky 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2015年第1期182-193,共12页
A large subset of corneal pathologies involves the formation of new vessels(neovascularization), leading to compromised visual acuity. This article aims to review the clinical causes and presentations of corneal neova... A large subset of corneal pathologies involves the formation of new vessels(neovascularization), leading to compromised visual acuity. This article aims to review the clinical causes and presentations of corneal neovascularization(CNV) by examining the mechanisms behind common CNV-related corneal pathologies, with a particular focus on herpes simplex stromal keratitis,contact lenses-induced keratitis and CNV secondary to keratoplasty. Moreover, we reviewed CNV in the context of different types of corneal transplantation and keratoprosthesis, and summarized the most relevant treatment available so far. 展开更多
关键词 CORNEA NEOVASCULARIZATION herpes simplex keratitis KERATOPLASTY contact lens KERATOPROSTHESIS
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Evolution in the treatment of metastatic colorectal carcinoma of the liver 被引量:9
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作者 Charlotte E Ariyan Ronald R salem 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第20期3253-3258,共6页
Metastatic colorectal cancer to the liver is associated with a uniform poor prognosis without treatment. Advances in therapy over the past decades have now allowed surgical resections of the liver to occur with a low ... Metastatic colorectal cancer to the liver is associated with a uniform poor prognosis without treatment. Advances in therapy over the past decades have now allowed surgical resections of the liver to occur with a low morbidity and mortality. Improvements in chemotherapy regimes have paralleled technical improvements and now allow a new group of patients to become eligible for surgical resection. This chapter will review the recent advances in surgical and chemotherapeutic regimes in metastatic colorectal cancer to the liver. 展开更多
关键词 Ethical tensions METASTATIC Colorectal Carcinoma LIVER
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Development of an Arabic version of the National Eye Institute Visual Function Questionnaire as a tool to study eye diseases patients in Egypt 被引量:8
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作者 Nizar Saleh Abdelfattah Mohamed Amgad +14 位作者 Ahmed A Salama Marina E Israel Ghada A Elhawary Ahmed E Radwan Mohamed M Elgayar Tamer M EL Nakhal Islam T Elkhateb Heba A Hashem Doha K Embaby Amira A Elabd Reem K Elwy Magdi S Yacoub Hamdy salem Mohamed Abdel-Baqy Ahmad Kassem 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2014年第5期891-897,共7页
AIM:To develop and test an Arabic version of the National Eye Institute Visual Function Questionnaire-25(NEI-VFQ-25).METHODS:NEI-VFQ-25 was translated into Arabic according to WHO translation guidelines. We enrolled a... AIM:To develop and test an Arabic version of the National Eye Institute Visual Function Questionnaire-25(NEI-VFQ-25).METHODS:NEI-VFQ-25 was translated into Arabic according to WHO translation guidelines. We enrolled adult consenting patients with bilateral chronic eye diseases who presented to 14 hospitals across Egypt from October to December 2012, and documented their clinical findings. Psychometric properties were then tested using STATA.RESULTS:We recruited 379 patients, whose mean age was(54.5±15)y. Of 46.2% were males, 227 had cataract,31 had glaucoma, 23 had retinal detachment, 37 had diabetic retinopathy, and 61 had miscellaneous visual defects. Non-response rate and the floor and ceiling numbers of the Arabic version(ARB-VFQ-25) were calculated. Internal consistency was high in all subscales(except general health), with Cronbach-α ranging from0.702-0.911. Test-retest reliability was high(intraclass correlation coefficient 0.79).CONCLUSION:RB-VFQ-25 isareliableandvalidtool for assessing visual functions of Arabic speaking patients. However, some questions had high non-response rates and should be substituted by available alternatives. Our results support the importance of including self-reported visual functions as part of routine ophthalmologic examination. 展开更多
关键词 ARABIC PSYCHOMETRICS questionnaires National Institutes of Health visual function questionnaire
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虚拟制造环境中虚拟手的行为构造 被引量:8
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作者 蔡娴娟 程成 +2 位作者 Alhazmi Marwah Mostafa Hamdy salem MongHeng Ear 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2015年第3期499-507,共9页
为了实现虚拟制造环境中智能高效的虚拟手,改善目前主流的依赖对用户手抓握动作跟踪的状况,提出一种适用于虚拟制造环境的虚拟手自主行为构造方法.通过在虚拟手结构模型上增加感知环设计,构建虚拟手的感知能力;结合文中提出的虚拟手三... 为了实现虚拟制造环境中智能高效的虚拟手,改善目前主流的依赖对用户手抓握动作跟踪的状况,提出一种适用于虚拟制造环境的虚拟手自主行为构造方法.通过在虚拟手结构模型上增加感知环设计,构建虚拟手的感知能力;结合文中提出的虚拟手三阶段感知算法实现虚拟手的自适应行为机制,极大地减轻了操作者的认知和操作负载;通过构造虚拟手手势集和手势状态转换模型,实现了虚拟手在复杂零件表面的连续抓握操作.文中还重点研究了复杂零件表面虚拟手的连续抓握的行为机制和相关算法.实验结果表明,文中的虚拟手具有很好的几何真实感和行为真实感;提出的方法具有良好的可用性、可靠性和实时性. 展开更多
关键词 虚拟手 行为仿真 虚拟制造 虚拟环境 感知算法 人机交互
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Alumina-coated Ag nanocrystal monolayers as surfaceenhanced Raman spectroscopy platforms for the direct spectroscopic detection of water splitting reaction intermediates 被引量:8
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作者 Xing Yi Ling Ruoxue Yan +7 位作者 Sylvia Lo Dat Tien Hoang Chong Liu Melissa A. Fardy Sher Bahadar Khan Abdullah M. Asiri salem M. Bawaked Peidong Yang 《Nano Research》 SCIE EI CAS CSCD 2014年第1期132-143,共12页
A novel Ag-alumina hybrid surface-enhanced Raman spectroscopy (SERS) platform has been designed for the spectroscopic detection of surface reactions in the steady state. Single crystalline and faceted silver (Ag) ... A novel Ag-alumina hybrid surface-enhanced Raman spectroscopy (SERS) platform has been designed for the spectroscopic detection of surface reactions in the steady state. Single crystalline and faceted silver (Ag) nanoparticles with strong light scattering were prepared in large quantity, which enables their reproducible self-assembly into large scale monolayers of Raman sensor arrays by the Langrnuir-Blodgett technique. The close packed sensor film contains high density of sub-nm gaps between sharp edges of Ag nanoparticles, which created large local electromagnetic fields that serve as "hot spots" for SERS enhancement. The SERS substrate was then coated with a thin layer of alumina by atomic layer deposition to prevent charge transfer between Ag and the reaction system. The photocatalytic water splitting reaction on a monolayer of anatase TiO2 nanoplates decorated with Pt co-catalyst nanoparticles was employed as a model reaction system. Reaction intermediates of water photooxidation were observed at the TiO2/solution interface under UV irradiation. The surface-enhanced Raman vibrations corresponding to peroxo, hydroperoxo and hydroxo surface intermediate species were observed on the TiO2 surface, suggesting that the photo-oxidation of water on these anatase TiO2 nanosheets may be initiated by a nucleophilic attack mechanism. 展开更多
关键词 surface-enhanced Ramanspectroscopy water splitting reaction reaction intermediates Ag nanocrystals
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Direct-fed microbes: A tool for improving the utilization of low quality roughages in ruminants 被引量:7
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作者 Mona M Y Elghandour Abdelfattah Z M salem +3 位作者 Jose S Martínez Castaeda Luis M Camacho Ahmed E Kholif Juan C Vázquez Chagoyán 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第3期526-533,共8页
For many years, ruminant nutritionists and microbiologists have been interested in manipulating the microbial ecosystem of the rumen to improve production efficiency of different ruminant species. Removal and restrict... For many years, ruminant nutritionists and microbiologists have been interested in manipulating the microbial ecosystem of the rumen to improve production efficiency of different ruminant species. Removal and restriction of antibiotics subtherapeutic uses from ruminant diets has amplified interest in improving nutrient utilization and animal performance and search for more safe alternatives. Some bacterial and fungal microorganisms as a direct-fed microbial(DFM) can be the most suitable solutions. Microorganisms that are commonly used in DFM for ruminants may be classified mainly as lactic acid producing bacteria(LAB), lactic acid utilizing bacteria(LUB), or other microorganism's species like Lactobacillus, Bifidobacterium, Enterococcus, Streptococcus, Bacillus, Propionibacterium, Megasphaera elsdenii and Prevotellabryantii, in addition to some fungal species of yeast such as Saccharomyces and Aspergillus. A definitive mode of action for bacterial or fungal DFM has not been established; although a variety of mechanisms have been suggested. Bacterial DFM potentially moderate rumen conditions, and improve weight gain and feed efficiency. Fungal DFM may reduce harmful oxygen from the rumen, prevent excess lactate production, increase feed digestibility, and alter rumen fermentation patterns. DFM may also compete with and inhibit the growth of pathogens, immune system modulation, and modulate microbial balance in the gastrointestinal tract. Improved dry matter intake, milk yield, fat corrected milk yield and milk fat content were obtained with DFM administration. However, the response to DFM is not constant; depending on dosages, feeding times and frequencies, and strains of DFM. Nonetheless, recent studies have supported the positive effects of DFM on ruminant performance. 展开更多
关键词 direct-fed microbial(DFM) mode of action RUMINANTS
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Particle Swarm Optimization-Based Hyperparameters Tuning of Machine Learning Models for Big COVID-19 Data Analysis
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作者 Hend S. salem Mohamed A. Mead Ghada S. El-Taweel 《Journal of Computer and Communications》 2024年第3期160-183,共24页
Analyzing big data, especially medical data, helps to provide good health care to patients and face the risks of death. The COVID-19 pandemic has had a significant impact on public health worldwide, emphasizing the ne... Analyzing big data, especially medical data, helps to provide good health care to patients and face the risks of death. The COVID-19 pandemic has had a significant impact on public health worldwide, emphasizing the need for effective risk prediction models. Machine learning (ML) techniques have shown promise in analyzing complex data patterns and predicting disease outcomes. The accuracy of these techniques is greatly affected by changing their parameters. Hyperparameter optimization plays a crucial role in improving model performance. In this work, the Particle Swarm Optimization (PSO) algorithm was used to effectively search the hyperparameter space and improve the predictive power of the machine learning models by identifying the optimal hyperparameters that can provide the highest accuracy. A dataset with a variety of clinical and epidemiological characteristics linked to COVID-19 cases was used in this study. Various machine learning models, including Random Forests, Decision Trees, Support Vector Machines, and Neural Networks, were utilized to capture the complex relationships present in the data. To evaluate the predictive performance of the models, the accuracy metric was employed. The experimental findings showed that the suggested method of estimating COVID-19 risk is effective. When compared to baseline models, the optimized machine learning models performed better and produced better results. 展开更多
关键词 Big COVID-19 Data Machine Learning Hyperparameter Optimization Particle Swarm Optimization Computational Intelligence
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Nano-Chitosan Loaded N Application for Improving Wheat Plants Yield: Impacts on Soil Nutrient Availability
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作者 Tarek Salah Ahmed salem Elsayed Mohamed Elskhariy +2 位作者 Abdelmonem Mahmoud Zayed Ahmed Ibrahim Mohamed Noha Adel Mahgoub 《Journal of Agricultural Chemistry and Environment》 2024年第4期384-395,共12页
This work was held to study the effect of chitosan nanoparticles and loaded N on the wheat plants. A field study was conducted during the winter season 2021/2022 cultivated with wheat (Triticum aestivum L.) on sandy s... This work was held to study the effect of chitosan nanoparticles and loaded N on the wheat plants. A field study was conducted during the winter season 2021/2022 cultivated with wheat (Triticum aestivum L.) on sandy soil at the experimental unit of the Faculty of Agriculture farm-Suez Canal University-Ismailia-Egypt. Results may indicate that the application of foliar chitosan NPs.-loaded nitrogen in different concentrations has been employed to enhance plant growth and productivity, Nano-chitosan loaded with N (500 mg/L) yielded the most grains and was more effective than the control and nano-chitosan loaded N (250 mg/L, 750 mg/L). 展开更多
关键词 Nano Fertilizer NPK CHITOSAN WHEAT Sandy Soil
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