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Hydration lubrication 被引量:43
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作者 jacob KLEIN 《Friction》 SCIE EI CAS 2013年第1期1-23,共23页
The hydration lubrication paradigm,whereby hydration layers are both strongly held by the charges they surround,and so can support large pressures without being squeezed out,and at the same time remain very rapidly re... The hydration lubrication paradigm,whereby hydration layers are both strongly held by the charges they surround,and so can support large pressures without being squeezed out,and at the same time remain very rapidly relaxing and so have a fluid response to shear,provides a framework for understanding,controlling,and designing very efficient boundary lubrication systems in aqueous and biological media.This review discusses the properties of confined water,which-unlike organic solvents-retains its fluidity down to molecularly thin films.It then describes lubrication by hydrated ions trapped between charged surfaces,and by other hydrated boundary species including charged and zwitterionic polymer brushes,surfactant monolayers,liposomes,and biological macromolecules implicated in synovial joint lubrication.Finally,challenges and prospects for future development of this new boundary lubrication approach are considered. 展开更多
关键词 hydration lubrication biolubrication boundary lubrication liposomes polymer brushes hydration repulsion hydration layers
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Vitamin D supplementation improves sustained virologic response in chronic hepatitis C (genotype 1)-nave patients 被引量:31
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作者 Saif Abu-Mouch Zvi Fireman +3 位作者 jacob Jarchovsky Abdel-Rauf Zeina Nimer Assy Liver Unit 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第47期5184-5190,共7页
AIM: To determine whether adding vitamin D, a potent immunomodulator, improves the hepatitis C virus (HCV) response to antiviral therapy. METHODS: Seventy-two consecutive patients with chronic HCV genotype 1 were rand... AIM: To determine whether adding vitamin D, a potent immunomodulator, improves the hepatitis C virus (HCV) response to antiviral therapy. METHODS: Seventy-two consecutive patients with chronic HCV genotype 1 were randomized into two groups: the treatment group (n = 36, 50% male, mean age 47 ± 11 years) received Peg-α-2b interferon (1.5 μg/kg per week) plus ribavirin (1000-1200 mg/d) together with vitamin D3 (2000 IU/d, target serum level > 32 ng/mL), and the control group (n = 36, 60% male, mean age 49 ± 7 years) received identical therapy without vitamin D. HCV-RNA was assessed by realtime polymerase chain reaction (sensitivity, 10 IU/mL). The sustained virologic response (SVR) was defined as undetectable HCV-RNA at 24 wk post-treatment. RESULTS: Clinical characteristics were similar in both groups. The treatment group had a higher mean bodymass index (27 ± 4 kg/m2 vs 24 ± 3 kg/m2, P < 0.01), viral load (50% vs 42%, P < 0.01), and fibrosis score (> F2: 42% vs 19%, P < 0.001) than the controls. At week 4, 16 (44%) treated patients and 6 (17%) controls were HCV-RNA negative (P < 0.001). At week 12, 34 (94%) treated patients and 17 (48%) controls were HCV-RNA negative (P < 0.001). At 24 wk post-treatment (SVR), 31 (86%) treated patients and 15 (42%) controls were HCV-RNA negative (P < 0.001). Viral load, advanced fibrosis and vitamin D supplementation were strongly and independently associated with SVR (multivariate analysis). Adverse events were mild and typical of Peg-α-2b/ribavirin. CONCLUSION: Adding vitamin D to conventional Peg-α-2b/ribavirin therapy for treatment-na■ve patients with chronic HCV genotype 1 infection significantly improves the viral response. 展开更多
关键词 Hepatitis C Vitamin D Sustained viral response Genotype 1 FIBROSIS
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From NAFLD to MAFLD:a“redefining”moment for fatty liver disease 被引量:24
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作者 Kenneth IZheng Jian-Gao Fan +4 位作者 Jun-Ping Shi Vincent Wai-Sun Wong Mohammed Eslam jacob George Ming-Hua Zheng 《Chinese Medical Journal》 SCIE CAS CSCD 2020年第19期2271-2273,共3页
The term non-alcoholic fatty liver disease(NAFLD)was coined in 1980 to characterize a disease similar to alcoholic fatty liver disease that developed in patients without a history of excessive alcohol intake.[1]Morpho... The term non-alcoholic fatty liver disease(NAFLD)was coined in 1980 to characterize a disease similar to alcoholic fatty liver disease that developed in patients without a history of excessive alcohol intake.[1]Morphologically,NAFLD is characterized by excess fatty infiltration of the liver in the absence of known causes of liver disease(eg,alcohol,autoimmune liver disease,viral hepatitis,etc).The clinical manifestations of NAFLD(both hepatic and extrahepatic)depend on the outcome of complex interactions between its primary drivers including poor lifestyle habits and diet,a dysfunctional microbiota,genetic predisposition,and environmental cues that result in metabolic dysfunction and liver disease.However,bringing all patients with their markedly different clinical courses under the NAFLD umbrella belies its complexity and implies a homogeneous disease state that then negatively impacts clinical management and a deeper understanding of pathogenesis.With advances in current knowledge on the spectrum of fatty liver diseases,it is apparent that the fourdecade-old outdated term NAFLD can no longer serve to usefully describe a highly heterogeneous disease.The disease as we understand it today not only impacts patients who consume alcohol and those who do not,but also potentially impacts all patients with any form of liver disease,by acting as a disease modifier.[2] 展开更多
关键词 NAFLD MORPHOLOGICAL markedly
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持续性姿势-感知性头晕(PPPD)诊断标准:Bárány学会前庭疾病分类委员会共识 被引量:24
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作者 李康之(译) 刘博(译) +8 位作者 顾平(审校) 杨旭(审校) Jeffrey PStaab Annegret Eckhardt-Henn Arata Horii Rolf jacob Michael Strupp Thomas Brandt Adolfo Bronstein 《神经损伤与功能重建》 2020年第2期63-72,共10页
本文提出被纳入前庭疾病国际分类(International Classification of Vestibular Disorders,ICVD)的持续性姿势-感知性头晕(PPPD)的诊断标准。PPPD虽然是一个新的医学术语,但该病的存在由来已久。前庭疾病分类委员会深入汇总、分析了近3... 本文提出被纳入前庭疾病国际分类(International Classification of Vestibular Disorders,ICVD)的持续性姿势-感知性头晕(PPPD)的诊断标准。PPPD虽然是一个新的医学术语,但该病的存在由来已久。前庭疾病分类委员会深入汇总、分析了近30年来恐惧性姿势性眩晕(Phobic Postural Vertigo,PPV)、空间运动不适(Space℃Motion Discomfort,SMD)、视觉性眩晕(Visual Vertigo,VV)和慢性主观性头晕(Chronic Subjective Dizziness,CSD)相关的研究,在此基础上提出了PPPD的诊断标准。临床上,头晕、不稳、非旋转性眩晕为PPPD的3个核心症状。PPPD患者常表现为这3个核心症状中的一个或多个,症状持续时间超过3个月,并且在直立姿势、主动/被动运动、暴露于移动视觉刺激或复杂视觉环境中时症状出现加重。PPPD可能与影响平衡系统或引起眩晕、不稳及头晕的疾病所触发有关,包括周围或中枢前庭病变、其他内科疾病或心理疾病。临床上,PPPD既可单独存在,也可与其他临床疾病共病。PPPD可能的亚型分类尚需进一步识别和验证。迄今为止,PPPD确切的病理生理机制尚不明确。新近研究表明,PPPD可能与躯体姿势控制、多感觉信息处理、威胁评估系统与空间定向系统皮质整合的功能异常相关。因此,PPPD被归类为慢性功能性前庭疾病,并不是结构性前庭疾病或精神心理性前庭疾病。 展开更多
关键词 慢性主观性头晕 恐惧性姿势性眩晕 空间运动不适 视觉性眩晕 分类 Bárány学会
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Recent advances in 2D,3D and higher-order topological photonics 被引量:22
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作者 Minkyung Kim Zubin jacob Junsuk Rho 《Light(Science & Applications)》 SCIE EI CAS CSCD 2020年第1期763-792,共30页
Over the past decade,topology has emerged as a major branch in broad areas of physics,from atomic lattices to condensed matter.In particular,topology has received significant attention in photonics because light waves... Over the past decade,topology has emerged as a major branch in broad areas of physics,from atomic lattices to condensed matter.In particular,topology has received significant attention in photonics because light waves can serve as a platform to investigate nontrivial bulk and edge physics with the aid of carefully engineered photonic crystals and metamaterials.Simultaneously,photonics provides enriched physics that arises from spin-1 vectorial electromagnetic fields.Here,we review recent progress in the growing field of topological photonics in three parts.The first part is dedicated to the basics of topological band theory and introduces various two-dimensional topological phases.The second part reviews three-dimensional topological phases and numerous approaches to achieve them in photonics.Last,we present recently emerging fields in topological photonics that have not yet been reviewed.This part includes topological degeneracies in nonzero dimensions,unidirectional Maxwellian spin waves,higher-order photonic topological phases,and stacking of photonic crystals to attain layer pseudospin.In addition to the various approaches for realizing photonic topological phases,we also discuss the interaction between light and topological matter and the efforts towards practical applications of topological photonics. 展开更多
关键词 TOPOLOGICAL TOPOLOGY DIMENSIONS
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miR-20b, miR-98, miR-125b-1*, and let-7e* as new potential diagnostic biomarkers in ulcerative colitis 被引量:20
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作者 Mehmet Coskun jacob Tveiten Bjerrum +3 位作者 Jakob Benedict Seidelin Jesper Thorvald Troelsen JΦrgen Olsen Ole Haagen Nielsen 《World Journal of Gastroenterology》 SCIE CAS 2013年第27期4289-4299,共11页
AIM:To use microarray-based miRNA profiling of colonic mucosal biopsies from patients with ulcerative colitis (UC), Crohn's disease (CD), and controls in order to identify new potential miRNA biomarkers in inflamm... AIM:To use microarray-based miRNA profiling of colonic mucosal biopsies from patients with ulcerative colitis (UC), Crohn's disease (CD), and controls in order to identify new potential miRNA biomarkers in inflammatory bowel disease. METHODS:Colonic mucosal pinch biopsies from the descending part were obtained endoscopically from patients with active UC or CD, quiescent UC or CD, as well as healthy controls. Total RNA was isolated and miRNA expression assessed using the miRNA microarray Geniom Biochip miRNA Homo sapiens (Febit GmbH, Heidelberg, Germany). Data analysis was carried out by principal component analysis and projection to latent structure-discriminant analysis using the SIMCA-P+12 software package (Umetrics, Umea, Sweden). The microarray data were subsequently validated by quantitative real-time polymerase chain reaction (qPCR) performed on colonic tissue samples from active UC patients (n = 20), patients with quiescent UC (n = 19), and healthy controls (n = 20). The qPCR results were analyzed with Mann-WhitneyU test.In silico prediction analysis were performed to identify potential miRNA target genes and the predicted miRNA targets were then compared with all UC associated susceptibility genes reported in the literature. RESULTS:The colonic mucosal miRNA transcriptome differs significantly between UC and controls, UC and CD, as well as between UC patients with mucosal inflammation and those without. However, no clear differences in the transcriptome of patients with CD and controls were found. The miRNAs with the strongest differential power were identified (miR-20b, miR-99a, miR-203, miR-26b, and miR-98) and found to be upregulated more than a 10-fold in active UC as compared to quiescent UC, CD, and controls. Two miRNAs, miR-125b-1* and let-7e*, were up-regulated more than 5-fold in quiescent UC compared to active UC, CD, and controls. Four of the seven miRNAs (miR-20b, miR-98, miR-125b-1*, and let-7e*) were validated by qPCR and found to be specifically upregulated in patients with UC. Usingin sili 展开更多
关键词 Biomarker Crohn’s DISEASE Diagnostics Inflammatory BOWEL DISEASE Microarray MicroRNA ULCERATIVE COLITIS
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MicroRNAs in inflammatory bowel disease-pathogenesis,diagnostics and therapeutics 被引量:19
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作者 Mehmet Coskun jacob Tveiten Bjerrum +1 位作者 Jakob Benedict Seidelin Ole Haagen Nielsen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第34期4629-4634,共6页
The pathogenesis of inflammatory bowel disease (IBD) is complex and largely unknown. Until recently, research has focused on the study of protein regulators in inflammation to reveal the cellular and molecular network... The pathogenesis of inflammatory bowel disease (IBD) is complex and largely unknown. Until recently, research has focused on the study of protein regulators in inflammation to reveal the cellular and molecular networks in the pathogenesis of IBD. However, in the last few years, new and promising insights have been generated from studies describing an association between an altered expression of a specific class of non-coding RNAs, called microRNAs (miRs or miRNAs) and IBD. The short (approximately 22 nucleotides), endogenous, single-stranded RNAs are evolutionary conserved inanimals and plants, and regulate specific target mRNAs at the post-transcriptional level. MiRNAs are involved in several biological processes, including development, cell differentiation, proliferation and apoptosis. Furthermore, it is estimated that miRNAs may be responsible for regulating the expression of nearly one-third of the genes in the human genome. Thus, miRNA deregulation often results in an impaired cellular function, and a disturbance of downstream gene regulation and signaling cascades, suggesting their implication in disease etiology. Despite the identification of more than 1900 mature human miRNAs, very little is known about their biological functions and functional targets. Recent studies have identified dysregulated miRNAs in tissue samples of IBD patients and have demonstrated similar differences in circulating miRNAs in the serum of IBD patients. Thus, there is great promise that miRNAs will aid in the early diagnosis of IBD, and in the development of personalized therapies. Here, we provide a short review of the current state-of-the-art of miRNAs in IBD pathogenesis, diagnostics and therapeutics. 展开更多
关键词 Biomarker Crohn's disease DIAGNOSTICS In-flammatory bowel disease MicroRNA THERAPEUTICS Ulcer-ative colitis
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高产植酸酶乳酸菌发酵对黑豆面包蛋白质品质及烘焙特性的影响 被引量:16
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作者 罗昆 曹伟超 +6 位作者 马子琳 武盟 Omedi jacob OJOBI 郑建仙 黄卫宁 李宁 Filip ARNAUT 《食品科学》 EI CAS CSCD 北大核心 2021年第6期111-117,共7页
从实验室获得1株高产植酸酶乳酸菌(L-19)并应用于黑豆酸面团面包,同时选用不产植酸酶的乳酸菌(K-12)作为对照。通过分析面包氨基酸组成和营养指标、蛋白质体外消化率、质构特性、超微结构和感官评定,研究其对黑豆酸面团面包蛋白质营养... 从实验室获得1株高产植酸酶乳酸菌(L-19)并应用于黑豆酸面团面包,同时选用不产植酸酶的乳酸菌(K-12)作为对照。通过分析面包氨基酸组成和营养指标、蛋白质体外消化率、质构特性、超微结构和感官评定,研究其对黑豆酸面团面包蛋白质营养及烘焙学特性的影响。结果表明:添加乳酸菌黑豆酸面团后,面包蛋白营养和烘焙品质都得到了明显改善,其中L-19酸面团面包(L-19SDB)效果最显著。与黑豆面包(BB)相比,L-19SDB植酸含量下降60.68%,蛋白质体外消化率由64.70%升高至73.93%,总氨基酸含量提高73%。同时与其他3组相比,L-19SDB有更好的氨基酸特征:其必需氨基酸与总氨基酸之比、必需氨基酸指数和生物价均为最高。面包烘焙品质方面,相比黑豆面包BB,L-19SDB和K-12SDB比容分别提高了31.45%和23.59%,硬度降低了68.79%和56.59%。通过ImageJ分析发现,L-19SDB芯囊组织更加均匀,感官评价总体可接受度最高(7.72分)。 展开更多
关键词 植酸酶 氨基酸组成 蛋白质体外消化率 黑豆酸面团 烘焙品质
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混菌发酵酸面团对全麦面包风味与烘焙特性的影响 被引量:16
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作者 邹奇波 程新 +7 位作者 陈诚 杨文丹 张宾乐 周黎源 黄金鑫 陈军民 黄卫宁 jacob Ojobi Omedi 《食品与机械》 北大核心 2020年第4期32-39,共8页
将食窦魏斯氏菌和马克斯克鲁维酵母进行混菌发酵,测定菌株生长曲线研究两菌种的共生作用,分析发酵24 h后纤维素酶活力以及胞外多糖(EPS)产量,比较混菌发酵全麦面包与单菌发酵全麦面包烘焙与风味特性的差异。结果表明,相比于单菌发酵酸... 将食窦魏斯氏菌和马克斯克鲁维酵母进行混菌发酵,测定菌株生长曲线研究两菌种的共生作用,分析发酵24 h后纤维素酶活力以及胞外多糖(EPS)产量,比较混菌发酵全麦面包与单菌发酵全麦面包烘焙与风味特性的差异。结果表明,相比于单菌发酵酸面团的菌落总数[乳酸菌9.51 lg(CFU/g),酵母菌8.21 lg(CFU/g)],混菌发酵酸面团体系(MBF)中的乳酸菌与酵母菌菌落数分别达到9.61,8.09 lg(CFU/g),说明两株菌具有良好的共生关系。相比于单一乳酸菌发酵,含有马克斯克鲁维酵母的混菌发酵酸面团中纤维素酶活力增加,胞外β-葡萄糖苷酶酶活为13.59 U/g,提高了128.40%。发酵24 h后,体系中水溶性的阿拉伯木聚糖含量从0.77 g/100 g上升至1.89 g/100 g。此外,相比于其他两组单菌发酵的全麦酸面团,混菌发酵全麦酸面团产EPS能力最高,为7.54 g/kg。相比未添加酸面团的全麦面包,含有混菌发酵全麦酸面团的面包(MBB)比容、弹性显著提高(P<0.05),面包芯硬度下降,混菌发酵全麦面包比容显著增加。风味特性结果表明,混菌发酵全麦面包的风味强度明显高于单一乳酸菌发酵,赋予全麦面包更浓郁的酒香和果香,感官评定证实其整体可接受度更高。 展开更多
关键词 全麦酸面团 食窦魏斯氏菌 马克斯克鲁维酵母 混菌发酵 纤维素酶 胞外多糖 烘焙特性
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Sirolimus inhibits growth of human hepatoma cells alone or combined with tacrolimus, while tacrolimus promotes cell growth 被引量:14
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作者 Guido Schumacher Marijke Oidtmann +6 位作者 Anne Rueggeberg Dietmar jacob Sven Jonas Jan M. Langrehr Ruth Neuhaus Marcus Bahra Peter Neuhaus 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第10期1420-1425,共6页
AIM: Standard immunosuppression after organ transplantation stimulates tumor growth. Sirolimus has a strong antiproliferative and a tumor inhibiting effect. The purpose is to assess the effect on tumor growth of the i... AIM: Standard immunosuppression after organ transplantation stimulates tumor growth. Sirolimus has a strong antiproliferative and a tumor inhibiting effect. The purpose is to assess the effect on tumor growth of the immunosuppressive compounds sirolimus and tacrolimus alone and in combination on cells of human hepatocellular carcinoma.METHODS: We used the human cell lines SK-Hep 1 and Hep 3B derived from hepatocellular carcinoma. Proliferation analyses after treatment with sirolimus, tacrolimus, or the combination of both were performed. FACS analyses were done to reveal cell cycle changes and apoptotic cell death. The expression of apoptosis-related proteins was estimated by Western blots.RESULTS: Sirolimus alone or combined with tacrolimus inhibited the growth of both cell lines after 5 d by up to 35% in SK-Hep 1 cells, and by up to 68% in Hep 3B cells at 25 ng/mL. Tacrolimus alone stimulated the growth by 12% after 5 ng/mL and by 25% after 25 ng/mL in Hep 3B cells. We found an increase of apoptotic Hep 3B cells from 6 to 16%, and a G1-arrest in SK-Hep 1 cells with an increase of cells from 61 to 82%, when sirolimus and tacrolimus were combined. Bcl-2 was down-regulated in Hep 3B, but not in SK-Hep 1 cells after combined treatment.CONCLUSION: Sirolimus appears to inhibit the growth of hepatocellular carcinoma cells alone and in combination with tacrolimus. Sirolimus seems to inhibit the growth stimulation of tacrolimus. 展开更多
关键词 SIROLIMUS TACROLIMUS Hepatocellular carcinoma Growth inhibition Apoptosis SK-Hep 1 HEP3B
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Combining computer vision and deep learning to enable ultra-scale aerial phenotyping and precision agriculture:A case study of lettuce production 被引量:18
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作者 Alan Bauer Aaron George Bostrom +6 位作者 Joshua Ball Christopher Applegate Tao Cheng Stephen Laycock Sergio Moreno Rojas jacob Kirwan Ji Zhou 《Horticulture Research》 SCIE 2019年第1期906-917,共12页
Aerial imagery is regularly used by crop researchers,growers and farmers to monitor crops during the growing season.To extract meaningful information from large-scale aerial images collected from the field,high-throug... Aerial imagery is regularly used by crop researchers,growers and farmers to monitor crops during the growing season.To extract meaningful information from large-scale aerial images collected from the field,high-throughput phenotypic analysis solutions are required,which not only produce high-quality measures of key crop traits,but also support professionals to make prompt and reliable crop management decisions.Here,we report AirSurf,an automated and open-source analytic platform that combines modern computer vision,up-to-date machine learning,and modular software engineering in order to measure yield-related phenotypes from ultra-large aerial imagery.To quantify millions of in-field lettuces acquired by fixed-wing light aircrafts equipped with normalised difference vegetation index(NDVI)sensors,we customised AirSurf by combining computer vision algorithms and a deep-learning classifier trained with over 100,000 labelled lettuce signals.The tailored platform,AirSurf-Lettuce,is capable of scoring and categorising iceberg lettuces with high accuracy(>98%).Furthermore,novel analysis functions have been developed to map lettuce size distribution across the field,based on which associated global positioning system(GPS)tagged harvest regions have been identified to enable growers and farmers to conduct precision agricultural practises in order to improve the actual yield as well as crop marketability before the harvest. 展开更多
关键词 COMPUTER analysis equipped
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Current concepts on the role of nitric oxide in portal hypertension 被引量:18
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作者 Liang Shuo Hu jacob George Jian Hua Wang 《World Journal of Gastroenterology》 SCIE CAS 2013年第11期1707-1717,共11页
Portal hypertension(PHT) is defined as a pathological increase in portal venous pressure and frequently accompanies cirrhosis.Portal pressure can be increased by a rise in portal blood flow,an increase in vascular res... Portal hypertension(PHT) is defined as a pathological increase in portal venous pressure and frequently accompanies cirrhosis.Portal pressure can be increased by a rise in portal blood flow,an increase in vascular resistance,or the combination.In cirrhosis,the primary factor leading to PHT is an increase in intra-hepatic resistance to blood flow.Although much of this increase is a mechanical consequence of architectural disturbances,there is a dynamic and reversible component that represents up to a third of the increased vascular resistance in cirrhosis.Many vasoactive substances contribute to the development of PHT.Among these,nitric oxide(NO) is the key mediator that paradoxically regulates the sinusoidal(intra-hepatic) and systemic/splanchnic circulations.NO deficiency in the liver leads to increased intra-hepatic resistance while increased NO in the circulation contributes to the hyperdynamic systemic/splanchnic circulation.NO mediated-angiogenesis also plays a role in splanchnic vasodilation and collateral circulation formation.NO donors reduce PHT in animals models but the key clinical challenge is the development of an NO donor or drug delivery system that selectively targets the liver. 展开更多
关键词 NITRIC oxide PORTAL HYPERTENSION HEPATIC stellate cell Liver CIRRHOSIS
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电磁力与射流流场中压力脉动作用下伺服阀力矩马达谐响应分析 被引量:17
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作者 彭敬辉 李松晶 jacob M Mchenya 《工程力学》 EI CSCD 北大核心 2013年第2期348-353,共6页
为揭示伺服阀自激噪声的产生机理,该文对伺服阀力矩马达的振动特性进行研究。通过分析喷嘴挡板式电液伺服阀的工作原理,给出了衔铁组件的受力数学模型。建立了单自由度系统的谐响应分析数学模型,分析了谐振频率与系统固有频率的关系... 为揭示伺服阀自激噪声的产生机理,该文对伺服阀力矩马达的振动特性进行研究。通过分析喷嘴挡板式电液伺服阀的工作原理,给出了衔铁组件的受力数学模型。建立了单自由度系统的谐响应分析数学模型,分析了谐振频率与系统固有频率的关系。采用ANSYS软件对电磁场和伺服阀内部流场作用下力矩马达的谐响应特性进行了分析,得出了力矩马达关键点处不同方向上的谐响应曲线,分析了其在0--4500Hz内的谐振规律。仿真结果表明,电磁场和流场的作用会激发力矩马达的高频振动,从而可能诱发高频自激噪声。 展开更多
关键词 自激噪声 衔铁组件 有限元 谐响应分析 耦合振动
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Molecular mechanisms of insulin resistance in chronic hepatitis C 被引量:17
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作者 Mark W Douglas jacob George 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第35期4356-4364,共9页
It is now widely recognized that chronic hepatitis C (CHC)is associated with insulin resistance(IR)and type 2 diabetes,so can be considered a metabolic disease.IR is most strongly associated with hepatitis C virus(HCV... It is now widely recognized that chronic hepatitis C (CHC)is associated with insulin resistance(IR)and type 2 diabetes,so can be considered a metabolic disease.IR is most strongly associated with hepatitis C virus(HCV)genotype 1,in contrast to hepatic steatosis, which is associated with genotype 3 infection.Apart from the well-described complications of diabetes,IR in CHC predicts faster progression to fibrosis and cirrhosis that may culminate in liver failure and hepatocellular carcinoma.More recently,it has been recognized that IR in CHC predicts a poor response to antiviral therapy. The molecular mechanisms for the association between IR and HCV infection are not well defined.This review will elaborate on the clinical associations between CHC and IR and summarize current knowledge regarding the molecular mechanisms that potentially mediate HCV-associated IR. 展开更多
关键词 Hepatitis C virus Insulin resistance Treatment response INTERFERON
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Role of ethanol in the regulation of hepatic stellate cell function 被引量:16
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作者 Jian-Hua Wang Robert G Batey jacob George 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第43期6926-6932,共7页
Evidence has accumulated to suggest an important role of ethanol and/or its metabolites in the pathogenesis of alcohol-related liver disease. In this review, the fibrogenic effects of ethanol and its metabolites on he... Evidence has accumulated to suggest an important role of ethanol and/or its metabolites in the pathogenesis of alcohol-related liver disease. In this review, the fibrogenic effects of ethanol and its metabolites on hepatic stellate cells (HSCs) are discussed. In brief, ethanol interferes with retinoid metabolism and its signaling, induces the release of fibrogenic cytokines such as transforming growth factor β-1 (TGFβ-1) from HSCs, up-regulates the gene expression of collagen I and enhances type I collagen protein production by HSCs. Ethanol further perpetuates an activated HSC phenotype through extracellular matrix remodeling. The underlying pathophysiologic mechanisms by which ethanol exerts these pro-fibrogenic effects on HSCs are reviewed. 展开更多
关键词 ETHANOL ACETALDEHYDE Hepatic stellate cells liver fibrosis Type I collagen gene Transcription factors Transforming growth factor β-1
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发酵麦麸对面包膳食纤维组成及烘焙特性的影响 被引量:14
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作者 张逢温 杨文丹 +6 位作者 张宾乐 汤晓娟 梁丽 邹奇波 郑建仙 黄卫宁 Omedi jacob Ojobi 《食品工业科技》 CAS 北大核心 2019年第5期1-6,11,共7页
采用马克斯克鲁维酵母发酵麦麸制得富含天然酶的功能配料,分析麦麸发酵过程中纤维素酶活力变化,比较制作的麦麸面包(B_1)、发酵麦麸面包(B_2)、木聚糖酶麦麸面包(B_3)和复合麦麸面包(B_4)的膳食纤维组成及烘焙特性的差异。结果表明:马... 采用马克斯克鲁维酵母发酵麦麸制得富含天然酶的功能配料,分析麦麸发酵过程中纤维素酶活力变化,比较制作的麦麸面包(B_1)、发酵麦麸面包(B_2)、木聚糖酶麦麸面包(B_3)和复合麦麸面包(B_4)的膳食纤维组成及烘焙特性的差异。结果表明:马克斯克鲁维酵母具有较强的胞外β-葡萄糖苷酶生产能力,其酶活为6.98 U/g;在48 h麦麸发酵过程中,外切葡聚糖酶和β-葡萄糖苷酶的酶活不断提高,其酶活分别增加至6.06和21.70 U/g,不溶性膳食纤维(IDF)也持续降解至38.30 g/100 g。面团搅拌、醒发过程中,还原糖含量不断增加,且添加发酵麦麸的面包效果最明显。相比未发酵麦麸面包,添加发酵麦麸的面包体积、弹性及持水力都显著提升(p <0.05),气孔结构更加细腻。制作的4种面包中总膳食纤维(TDF)和阿拉伯木聚糖(AX)含量没有显著差异,而添加发酵麦麸及木聚糖酶都能促进面包中IDF和AX溶解。 展开更多
关键词 发酵麦麸 面包 纤维素酶 膳食纤维 烘焙特性
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经NO-cGMP-PDE5通路治疗勃起功能障碍的中药研究进展 被引量:16
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作者 廖晖 jacob Rajfer 《中华男科学杂志》 CAS CSCD 2012年第3期260-265,共6页
自1990年首次阐明小分子一氧化氮(NO)与阴茎平滑肌松弛之间有紧密联系后,20多年间ED的基础研究取得了很大进展。一氧化氮-环鸟苷酸-磷酸二酯酶5(NO-cGMP-PDE5)通路在ED治疗中的重要作用及相关研究为临床治疗ED提供了坚实的基础。中药治... 自1990年首次阐明小分子一氧化氮(NO)与阴茎平滑肌松弛之间有紧密联系后,20多年间ED的基础研究取得了很大进展。一氧化氮-环鸟苷酸-磷酸二酯酶5(NO-cGMP-PDE5)通路在ED治疗中的重要作用及相关研究为临床治疗ED提供了坚实的基础。中药治疗ED的历史悠久,目前已阐明部分中药经NO-cGMP-PDE5通路治疗ED的分子生物学机制。本文综述了相关研究。 展开更多
关键词 勃起功能障碍 NO—cGMP—PDE5通路 中药
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Helicobacter pylori : Friend or foe? 被引量:16
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作者 Stephen David Howard Malnick Ehud Melzer +2 位作者 Malka Attali Gabriel Duek jacob Yahav 《World Journal of Gastroenterology》 SCIE CAS 2014年第27期8979-8985,共7页
Helicobacter pylori(H. pylori) is a Gram-negative spiral bacterium that is present in nearly half the world's population. It is the major cause of peptic ulcer disease and a recognized cause of gastric carcinoma. ... Helicobacter pylori(H. pylori) is a Gram-negative spiral bacterium that is present in nearly half the world's population. It is the major cause of peptic ulcer disease and a recognized cause of gastric carcinoma. In addition, it is linked to non-ulcer dyspepsia, vitamin B12 deficiency, iron-deficient anemia and immune thrombocytopenic purpura. These conditions are indications for testing and treatment according to current guidelines. An additional indication according to the guidelines is "anyone with a fear of gastric cancer" which results in nearly every infected person being eligible for eradication treatment. There may be beneficial effects of H. pylori in humans, including protection from gastroesophageal reflux disease and esophageal adenocarcinoma. In addition, universal treatment will be extremely expensive(more than $32 billion in the United States), may expose the patients to adverse effects such as anaphylaxis and Clostridium difficile infection, as well as contributing to antibiotic resistance. There may also be an as yet uncertain effect on the fecal microbiome. There is a need for robust clinical data to assist in decision-making regarding treatment of H. pylori infection. 展开更多
关键词 HELICOBACTER PYLORI Treatment Cost BENEFIT Cancer
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功能性乳酸菌发酵黑豆麦麸酸面团面包的营养及烘焙特性 被引量:12
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作者 曹伟超 张宾乐 +6 位作者 Omedi jacob OJOBI 黄璟 陈诚 邹奇波 黄卫宁 李宁 高铁成 《食品科学》 EI CAS CSCD 北大核心 2022年第2期142-150,共9页
将黑豆及麦麸作为发酵基质,分别以高产植酸酶的乳酸片球菌(Pediococcus acidilactici)L-19及产β-葡萄糖苷酶的戊糖片球菌(Pediococcus pentosaceus)J-28作为发酵剂制作酸面团面包。探究菌株的生长、酸化及产酶特性,分析体系中植酸与膳... 将黑豆及麦麸作为发酵基质,分别以高产植酸酶的乳酸片球菌(Pediococcus acidilactici)L-19及产β-葡萄糖苷酶的戊糖片球菌(Pediococcus pentosaceus)J-28作为发酵剂制作酸面团面包。探究菌株的生长、酸化及产酶特性,分析体系中植酸与膳食纤维的变化,采用低场核磁共振及磁共振成像技术表征面筋的水合情况,并比较面包面团的物性与微观结构差异,同时对黑豆麦麸酸面团面包的营养及感官品质进行评价。结果表明:在黑豆麦麸基质中,两株乳酸菌生长良好,酸化能力强,两者表现出不同的产酶特性。经发酵后,两种酸面团的植酸降解率分别达到81.08%、59.79%,可溶性膳食纤维含量在总膳食纤维中的占比由发酵前的22.49%分别提高至31.47%、44.15%。黑豆及麦麸干扰面筋水合,不利于形成连续的网络结构,而乳酸菌发酵能够降低黑豆及麦麸对面筋网络的破坏作用。在营养方面,两种酸面团面包的总膳食纤维含量均高于6%,蛋白质含量分别达到13.82%、13.91%,并且具有更优的氨基酸组成模式及更高的体外蛋白消化率。因此,实验中的两株乳酸菌能够有效改善黑豆麦麸酸面团面包的营养及感官品质,具有较佳的应用潜力。 展开更多
关键词 功能性乳酸菌 黑豆麦麸酸面团 面筋网络 流变特性 营养评价
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Peritoneal dialysis associated infections: An update on diagnosis and management 被引量:13
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作者 jacob A Akoh 《World Journal of Nephrology》 2012年第4期106-122,共17页
Peritoneal dialysis (PD) is associated with a high risk of infection of the peritoneum, subcutaneous tunnel and catheter exit site. Although quality standards demand an infection rate 〈 0.67 episodes/patient/year o... Peritoneal dialysis (PD) is associated with a high risk of infection of the peritoneum, subcutaneous tunnel and catheter exit site. Although quality standards demand an infection rate 〈 0.67 episodes/patient/year on dialy-sis, the reported overall rate of PD associated infection is 0.24-1.66 episodes/patient/year. It is estimated that for every 0.5-per-year increase in peritonitis rate, the risk of death increases by 4% and 18% of the episodes resulted in removal of the PD catheter and 3.5% re-sulted in death. Improved diagnosis, increased aware-ness of causative agents in addition to other measures will facilitate prompt management of PD associated infection and salvage of PD modality. The aims of this review are to determine the magnitude of the infection problem, identify possible risk factors and provide an update on the diagnosis and management of PD as-sociated infection. Gram-positive cocci such as Staphy-lococcus epidermidis , other coagulase negative staphy-lococcoci, and Staphylococcus aureus (S. aureus ) are the most frequent aetiological agents of PD-associated peritonitis worldwide. Empiric antibiotic therapy must cover both gram-positive and gram-negative organ-isms. However, use of systemic vancomycin and cip-rofoxacin administration for example, is a simple and efficient first-line protocol antibiotic therapy for PD peritonitis - success rate of 77%. However, for fungal PD peritonitis, it is now standard practice to remove PD catheters in addition to antifungal treatment for a minimum of 3 wk and subsequent transfer to hemodi-alysis. To prevent PD associated infections, prophylactic antibiotic administration before catheter placement, adequate patient training, exit-site care, and treatment for S. aureus nasal carriage should be employed. Mupi-rocin treatment can reduce the risk of exit site infection by 46% but it cannot decrease the risk of peritonitis due to all organisms. 展开更多
关键词 Exit site infection PERITONITIS Tunnel infec-tion Polymicrobial infection Catheter removal Dialysis modality change Fungal peritonitis Sclerosing encap-sulating peritonitis Peritoneal dialysis
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