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镉胁迫对不同水稻基因型植株生长和抗氧化酶系统的影响 被引量:108
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作者 邵国胜 muhammad Jaffar Hassan +1 位作者 章秀福 张国平 《中国水稻科学》 CAS CSCD 北大核心 2004年第3期239-244,共6页
以籽粒镉积累水平不同的两种品种 (丙 972 5 2 ,低积累型 ;秀水 6 3,高积累型 )为材料 ,研究了镉胁迫对水稻植株生长和抗氧化酶系统的影响。采用水培试验 ,镉处理设 0 .0、0 .1、1.0和 5 .0 μmol/L 4个水平。结果表明 ,镉胁迫抑制植株... 以籽粒镉积累水平不同的两种品种 (丙 972 5 2 ,低积累型 ;秀水 6 3,高积累型 )为材料 ,研究了镉胁迫对水稻植株生长和抗氧化酶系统的影响。采用水培试验 ,镉处理设 0 .0、0 .1、1.0和 5 .0 μmol/L 4个水平。结果表明 ,镉胁迫抑制植株生长和叶绿素合成 ,改变植株丙二醛 (MDA)含量和超氧物歧化酶 (SOD)、过氧化氢酶 (CAT)、过氧化物酶 (POD)活性。在抗氧化酶活性上 ,根和地上部对镉胁迫的反应存在着差异。总体上 ,SOD、CAT和POD活性随镉水平的提高而减少 ,而MDA含量则表现相反。根和地上部MDA含量随着培养液中镉浓度提高而增加 ,且增加幅度秀水 6 3明显大于丙 972 5 2。与对照相比 ,生长在 5 .0 μmol/LCd处理下的植株 ,SOD活性在孕穗期下降 4 6 %~ 5 2 % ,在分蘖期仅下降 13%~ 19%。高浓度镉胁迫下 ,两品种在MDA含量的增加幅度和叶绿素含量的降低幅度上表现不同 ,显示出它们对镉的耐性存在着差异。 展开更多
关键词 镉胁迫 水稻 基因型 植株生长 抗氧化酶 耐性 浓度
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Clinical epidemiology and disease burden of nonalcoholic fatty liver disease 被引量:81
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作者 Brandon J Perumpail muhammad Ali Khan +3 位作者 Eric R Yoo George Cholankeril Donghee Kim Aijaz Ahmed 《World Journal of Gastroenterology》 SCIE CAS 2017年第47期8263-8276,共14页
Nonalcoholic fatty liver disease(NAFLD) is defined as the presence of hepatic fat accumulation after the exclusion of other causes of hepatic steatosis, including other causes of liver disease, excessive alcohol consu... Nonalcoholic fatty liver disease(NAFLD) is defined as the presence of hepatic fat accumulation after the exclusion of other causes of hepatic steatosis, including other causes of liver disease, excessive alcohol consumption, and other conditions that may lead to hepatic steatosis. NAFLD encompasses a broad clinical spectrum ranging from nonalcoholic fatty liver to nonalcoholic steatohepatitis(NASH), advanced fibrosis, cirrhosis, and finally hepatocellular carcinoma(HCC). NAFLD is the most common liver disease in the world and NASH may soon become the most common indication for liver transplantation. Ongoing persistence of obesity with increasing rate of diabetes will increase the prevalence of NAFLD, and as this population ages, many will develop cirrhosis and end-stage liver disease. There has been a general increase in the prevalence of NAFLD, with Asia leading the rise, yet the United States is following closely behind with a rising prevalence from 15% in 2005 to 25% within 5 years. NAFLD is commonly associated with metabolic comorbidities, including obesity, type Ⅱ diabetes, dyslipidemia, and metabolic syndrome. Our understanding of the pathophysiology of NAFLD is constantly evolving. Based on NAFLD subtypes, it has the potential to progress into advanced fibrosis, end-stage liver disease and HCC. The increasing prevalence of NAFLD with advanced fibrosis, is concerning because patients appear toexperience higher liver-related and non-liver-related mortality than the general population. The increased morbidity and mortality, healthcare costs and declining health related quality of life associated with NAFLD makes it a formidable disease, and one that requires more in-depth analysis. 展开更多
关键词 Nonalcoholic fatty liver disease Hepatic steatosis Fatty liver PREVALENCE INCIDENCE FIBROSIS Risk factor EPIDEMIOLOGY OUTCOMES Nonalcoholic steatohepatitis
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基于波形相似度比较的线路快速纵联保护研究 被引量:39
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作者 陈乐 薄志谦 +7 位作者 林湘宁 魏繁荣 余梦琪 金能 muhammad Shoaib Khalid 李正天 黄景光 邓科 《中国电机工程学报》 EI CSCD 北大核心 2017年第17期5018-5027,共10页
针对基于工频量线路纵联保护动作速度受制于滤波算法数据窗以及抗干扰能力不足的问题,提出一种基于波形相似度比较的线路快速纵联保护算法。该方法利用故障发生后故障线路两侧波形间不一致形变的特征,通过Hausdorff距离算法对包括故障... 针对基于工频量线路纵联保护动作速度受制于滤波算法数据窗以及抗干扰能力不足的问题,提出一种基于波形相似度比较的线路快速纵联保护算法。该方法利用故障发生后故障线路两侧波形间不一致形变的特征,通过Hausdorff距离算法对包括故障暂态时刻在内的任意时刻信号进行相似度比较,实现故障的快速识别和切除。该文结合算法特点提出对应的保护整定方法,并在整定的基础上分析算法的动作特性。针对原有Hausdorff距离算法受异常数据影响的缺陷,分析线路保护可能面临的异常数据特征,提出相应的改进策略。理论分析和仿真试验验证了所提算法的有效性和优越性。 展开更多
关键词 波形相似度 HAUSDORFF距离 纵联保护 高阻接地 异常数据
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影响烤烟烟碱合成与代谢的因素及其机理分析 被引量:38
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作者 谢志坚 涂书新 +6 位作者 张嵚 李海蓝 韩丹 muhammad Imtiaz 徐昌旭 刘光荣 罗华汉 《核农学报》 CAS CSCD 北大核心 2014年第4期714-719,共6页
烟碱是影响烤烟烟叶质量的重要指标,其含量的高低影响烟叶制品的吸食质量与安全性。烤烟烟叶(尤其是上部叶)中烟碱含量过高已经成为提高其在工业上可用性的关键限制性因素,因此,烟碱是国内外烟草学者研究烟草的重要研究对象。目前,影响... 烟碱是影响烤烟烟叶质量的重要指标,其含量的高低影响烟叶制品的吸食质量与安全性。烤烟烟叶(尤其是上部叶)中烟碱含量过高已经成为提高其在工业上可用性的关键限制性因素,因此,烟碱是国内外烟草学者研究烟草的重要研究对象。目前,影响烟碱合成与代谢的因素主要可分为内因(遗传因素)和外因(农艺栽培措施和气候环境等)。文章结合实例综述了这些影响烤烟烟碱的因素并分析了其机理,为优质烟叶生产提供一定理论依据与参考。 展开更多
关键词 烤烟 烟碱 合成与代谢 影响因素 机理
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辣椒热泵干燥特性及工艺参数优化 被引量:35
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作者 姬长英 蒋思杰 +2 位作者 张波 郭俊 muhammad Sohail Memon 《农业工程学报》 EI CAS CSCD 北大核心 2017年第13期296-302,共7页
为了提高干制辣椒品质,降低干燥能耗,该文应用热泵干燥技术干燥辣椒。首先探究干燥温度和铺料厚度对干燥特性的影响,绘制出含水率和干燥速率变化曲线。在此基础上,将分阶段控温和改变铺料厚度结合起来对辣椒进行热泵干燥,运用响应面法中... 为了提高干制辣椒品质,降低干燥能耗,该文应用热泵干燥技术干燥辣椒。首先探究干燥温度和铺料厚度对干燥特性的影响,绘制出含水率和干燥速率变化曲线。在此基础上,将分阶段控温和改变铺料厚度结合起来对辣椒进行热泵干燥,运用响应面法中的Box-Behnken设计,考察第一阶段温度、第二阶段温度、铺料厚度和三者的交互作用对品质得分、单位能耗、干燥时间的影响,并建立回归方程,得出最佳工艺参数。结论如下:温度越高,干燥速率越大,含水率下降越快;铺料厚度越大,干燥速率越小,含水率下降越慢;第一阶段温度是影响单位能耗的主要因素(P<0.05),较低的第一阶段温度能降低单位能耗;第二阶段温度对品质得分影响显著(P<0.05),对干燥时间影响极显著(P<0.01),第二阶段温度在60℃左右时能得到品质较佳的干辣椒,且在一定程度上提高了干燥效率;铺料厚度对品质得分、干燥时间的影响极显著(P<0.01),对单位能耗的影响显著(P<0.05),铺料厚度在45 mm左右干燥获得的辣椒品质较佳,而且能节约能耗,提高干燥效率。综合优化参数为:第一阶段温度48℃、第二阶段温度61℃、铺料厚度44 mm,在此工艺条件下获得的干燥辣椒品质得分为8.64,单位能耗为92.05 k J/kg,干燥时间为896.02 min。研究结果为热泵干燥技术应用于辣椒干制提供参考。 展开更多
关键词 干燥 品质控制 优化 辣椒 热泵 参数
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急性脑梗死静脉溶栓后早期神经功能恶化与血清白蛋白水平的关系研究 被引量:34
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作者 钱新宇 吕金峰 +2 位作者 Bilal muhammad 杜波 耿德勤 《中国医师进修杂志》 2019年第4期318-324,共7页
目的探讨急性脑梗死静脉溶栓后早期神经功能恶化(END)与血清白蛋白水平的关系。方法收集2017年1月至2018年8月发病4.5 h内接受阿替普酶静脉溶栓治疗患者的临床资料。根据是否出现END,分为恶化组和非恶化组,分析血清白蛋白水平与END发生... 目的探讨急性脑梗死静脉溶栓后早期神经功能恶化(END)与血清白蛋白水平的关系。方法收集2017年1月至2018年8月发病4.5 h内接受阿替普酶静脉溶栓治疗患者的临床资料。根据是否出现END,分为恶化组和非恶化组,分析血清白蛋白水平与END发生的相关性。结果共纳入148例患者,其中恶化组39例,非恶化组109例。与非恶化组相比,恶化组总蛋白水平、白蛋白水平和淋巴细胞计数较低,且差异有统计学意义(P<0.05)。恶化组的中性粒细胞计数、红细胞分布宽度、国际标准化比值、纤维蛋白(原)降解产物以及入院时美国国立卫生研究院卒中量表(NIHSS)评分高于非恶化组,差异有统计学意义(P<0.05)。恶化组多伴有心房颤动,且两组在血管狭窄程度及梗死部位方面比较差异也有统计学意义(P<0.05)。多因素Logistic回归分析显示,血清白蛋白(OR=0.873,95%CI 0.768~0.993)、入院时NIHSS评分(OR=1.120,95%CI 1.008~1.245)、中性粒细胞计数(OR=1.271,95%CI 1.048~1.542),以及心源性卒中和责任血管狭窄程度均可能影响急性脑梗死静脉溶栓的短期预后。出院时改良Rankin量表(mRS)评分(平均14 d)与白蛋白水平呈显著负相关(r=-0.205,P=0.013)。结论相比于非恶化患者,恶化患者的白蛋白水平较低。高水平的血清白蛋白是急性缺血性脑卒中静脉溶栓后END的保护因素。血清白蛋白水平与患者的短期预后存在相关性,白蛋白水平越低,mRS评分越高,预后越差。 展开更多
关键词 静脉溶栓 白蛋白 危险因素 早期神经功能恶化
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Type Ⅰ and type Ⅱ Helicobacter pylori infection status and their impact on gastrin and pepsinogen level in a gastric cancer prevalent area 被引量:36
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作者 Lin Yuan Jun-Bo Zhao +8 位作者 Ying-Lei Zhou Ya-Bin Qi Qiong-Ya Guo Hai-Hui Zhang muhammad Noman Khan Ling Lan Chang-He Jia Yan-Rui Zhang Song-Ze Ding 《World Journal of Gastroenterology》 SCIE CAS 2020年第25期3673-3685,共13页
BACKGROUND Type I Helicobacter pylori(H.pylori)infection causes severe gastric inflammation and is a predisposing factor for gastric carcinogenesis.However,its infection status in stepwise gastric disease progression ... BACKGROUND Type I Helicobacter pylori(H.pylori)infection causes severe gastric inflammation and is a predisposing factor for gastric carcinogenesis.However,its infection status in stepwise gastric disease progression in this gastric cancer prevalent area has not been evaluated;it is also not known its impact on commonly used epidemiological gastric cancer risk markers such as gastrin-17(G-17)and pepsinogens(PGs)during clinical practice.AIM To explore the prevalence of type I and type II H.pylori infection status and their impact on G-17 and PG levels in clinical practice.METHODS Thirty-five hundred and seventy-two hospital admitted patients with upper gastrointestinal symptoms were examined,and 523 patients were enrolled in this study.H.pylori infection was confirmed by both 13C-urea breath test and serological assay.Patients were divided into non-atrophic gastritis(NAG),nonatrophic gastritis with erosion(NAGE),chronic atrophic gastritis(CAG),peptic ulcers(PU)and gastric cancer(GC)groups.Their serological G-17,PG I and PG II values and PG I/PG II ratio were also measured.RESULTS A total H.pylori infection rate of 3572 examined patients was 75.9%,the infection rate of 523 enrolled patients was 76.9%,among which type I H.pylori infection accounted for 72.4%(291/402)and type II was 27.6%;88.4%of GC patients were H.pylori positive,and 84.2%of them were type I infection,only 11.6%of GC patients were H.pylori negative.Infection rates of type I H.pylori in NAG,NAGE,CAG,PU and GC groups were 67.9%,62.7%,79.7%,77.6%and 84.2%,respectively.H.pylori infection resulted in significantly higher G-17 and PG II values and decreased PG I/PG II ratio.Both types of H.pylori induced higher G-17 level,but type I strain infection resulted in an increased PG II level and decreased PG I/PG II ratio in NAG,NAGE and CAG groups over uninfected controls.Overall PG I levels showed no difference among all disease groups and in the presence or absence of H.pylori;in stratified analysis,its level was increased in GC and PU patients in H.pylori a 展开更多
关键词 Helicobacter pylori Chronic gastric diseases GASTRIN-17 PEPSINOGEN Gastric cancer
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考虑可转移负荷效率的风/光/柴/蓄孤岛微网日运行能量控制优化策略 被引量:36
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作者 魏繁荣 随权 +7 位作者 林湘宁 李正天 陈乐 邓科 薄志谦 黄景光 muhammad Shoaib Khalid Owolabi Sunday Adio 《中国电机工程学报》 EI CSCD 北大核心 2018年第4期1045-1053,共9页
大型负荷尤其是可转移负荷的效率–功率特性常常被忽视,因此考虑风/光/柴/蓄微网系统的运行调度是不经济的。该文提出一种考虑可转移负荷效率的风/光/柴/蓄微网能量控制优化策略。首先以典型的可转移负荷——反渗透型制淡设备为例,建立... 大型负荷尤其是可转移负荷的效率–功率特性常常被忽视,因此考虑风/光/柴/蓄微网系统的运行调度是不经济的。该文提出一种考虑可转移负荷效率的风/光/柴/蓄微网能量控制优化策略。首先以典型的可转移负荷——反渗透型制淡设备为例,建立包含设备工作全程的淡水输入–产出模型,实时计算其功率–效率特性曲线。在考虑制淡设备功率特性、蓄电池寿命(使用成本)、柴油机工作效率等因素的基础上,以燃料及蓄电池使用成本最少为目标,提出一种风/光/柴/蓄微网系统的日运行能量控制优化策略。通过与两种典型微网能量控制方案进行比较,仿真结果验证在包含可转移负荷的微网场景中,针对各种可能的储能设备和燃料的使用成本组合,在淡水需求量一定时,所提策略均具有较好的成本优势,为包含可转移负荷的微网经济运行策略制定提供了全新的视角。 展开更多
关键词 可转移负荷 制淡设备 功率–效率特性 使用成本 能量控制优化
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Roux-en-Y versus BillrothⅠreconstruction after distal gastrectomy for gastric cancer:A meta-analysis 被引量:35
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作者 Jun-Jie Xiong Kiran Altaf +8 位作者 muhammad A Javed Quentin M Nunes Wei Huang Gang Mai Chun-Lu Tan Rajarshi Mukherjee Robert Sutton Wei-Ming Hu Xu-Bao Liu 《World Journal of Gastroenterology》 SCIE CAS 2013年第7期1124-1134,共11页
AIM: To conduct a meta-analysis to compare Roux-en-Y (R-Y) gastrojejunostomy with gastroduodenal Billroth?I?(B-I) anastomosis after distal gastrectomy (DG) for gastric cancer.METHODS: A literature search was performed... AIM: To conduct a meta-analysis to compare Roux-en-Y (R-Y) gastrojejunostomy with gastroduodenal Billroth?I?(B-I) anastomosis after distal gastrectomy (DG) for gastric cancer.METHODS: A literature search was performed to identify studies comparing R-Y with B-I?after DG for gastric cancer from January 1990 to November 2012 in Medline, Embase, Science Citation Index Expanded and the Cochrane Central Register of Controlled Trials in The Cochrane Library. Pooled odds ratios (OR) or weighted mean differences (WMD) with 95%CI were calculated using either ?xed or random effects model. Operative outcomes such as operation time, intraoperative blood loss and postoperative outcomes such as anastomotic leakage and stricture, bile re?ux, remnant gastritis, re?ux esophagitis, dumping symptoms, delayed gastric emptying and hospital stay were the main outcomes assessed. Meta-analyses were performed using RevMan 5.0 software (Cochrane library).RESULTS: Four randomized controlled trials (RCTs) and 9 non-randomized observational clinical studies (OCS) involving 478 and 1402 patients respectively were included. Meta-analysis of RCTs revealed that R-Y reconstruction was associated with a reduced bile re?ux (OR 0.04, 95%CI: 0.01, 0.14; P < 0.00?001) and remnant gastritis (OR 0.43, 95%CI: 0.28, 0.66; P = 0.0001), however needing a longer operation time (WMD 40.02, 95%CI: 13.93, 66.11; P = 0.003). Meta-analysis of OCS also revealed R-Y reconstruction had a lower incidence of bile re?ux (OR 0.21, 95%CI: 0.08, 0.54; P = 0.001), remnant gastritis (OR 0.18, 95%CI: 0.11, 0.29; P < 0.00?001) and re?ux esophagitis (OR 0.48, 95%CI: 0.26, 0.89; P = 0.02). However, this reconstruction method was found to be associated with a longer operation time (WMD 31.30, 95%CI: 12.99, 49.60; P = 0.0008).CONCLUSION: This systematic review point towards some clinical advantages that are rendered by R-Y compared to B-I?reconstruction post DG. However there is a need for further adequately powered, well-designed RCTs comparing the same. 展开更多
关键词 Gastric cancer Distal gastrectomy ROUX-EN-Y Billroth I RECONSTRUCTION META-ANALYSIS
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秸秆还田对土壤微生物影响的研究进展 被引量:35
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作者 伍玉鹏 彭其安 +2 位作者 muhammad Shaaban 郝蓉 胡荣桂 《中国农学通报》 CSCD 2014年第29期175-183,共9页
秸秆还田是有效利用秸秆资源的重要途径。土壤微生物在秸秆腐解和营养元素释放过程中具有举足轻重的作用,而另一方面秸秆本身也会对土壤微生物产生较大的影响。秸秆还田概况入手,从不同的秸秆还田方式、外源添加物、不同的秸秆还田量、... 秸秆还田是有效利用秸秆资源的重要途径。土壤微生物在秸秆腐解和营养元素释放过程中具有举足轻重的作用,而另一方面秸秆本身也会对土壤微生物产生较大的影响。秸秆还田概况入手,从不同的秸秆还田方式、外源添加物、不同的秸秆还田量、耕作制度和转基因秸秆几个方面综述了目前国内外秸秆还田对土壤微生物影响的研究报告。目前已有文献的研究大多集中在土壤微生物量方面,但并没有形成一致的观点,且缺乏对土壤微生物长期动态和功能群的研究。据此认为应在今后的研究中加强以下几个方面:以更为先进的方法结合多种研究手段揭示秸秆还田过程中土壤微生物的实际情况;开展关于秸秆分解整个过程中土壤微生物的动态变化研究;以微生物功能群为单位研究秸秆还田对微生物的影响;采用多种不同的方法和长期的观察以研究转基因作物秸秆还田后对土壤微生物生态的影响。 展开更多
关键词 秸秆还田 土壤微生物 影响 综述
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Current and Future Treatment of Hepatocellular Carcinoma:An Updated Comprehensive Review 被引量:34
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作者 Saleh Daher muhammad Massarwa +1 位作者 Ariel A. Benson Tawfik Khoury 《Journal of Clinical and Translational Hepatology》 SCIE 2018年第1期69-78,共10页
Hepatocellular carcinoma(HCC)is among the leading causes of cancer-related mortality.The principal treatment is surgical resection or liver transplantation,depending on whether the patient is a suitable transplant can... Hepatocellular carcinoma(HCC)is among the leading causes of cancer-related mortality.The principal treatment is surgical resection or liver transplantation,depending on whether the patient is a suitable transplant candidate.However,in most patients with HCC the diagnosis is often late,thereby excluding the patients from definitive surgical resection.Medical treatment includes sorafenib,which is the most commonly used systemic therapy;although,it has been shown to only minimally impact patient survival by several months.Chemotherapy and radiotherapy are generally ineffective.Due to the poor prognosis of patients with HCC,newer treatments are needed with several being in development,either in preclinical or clinical studies.In this review article,we provide an update on the current and future medical and surgical management of HCC. 展开更多
关键词 HCC TREATMENTS SORAFENIB MORTALITY
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Effects of Bacillus coagulans supplementation on the growth performance and gut health of broiler chickens with Clostridium perfringens-induced necrotic enteritis 被引量:33
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作者 Yuanyuan Wu Yujing Shao +5 位作者 Bochen Song Wenrui Zhen Zhong Wang Yuming Guo muhammad Suhaib Shahid Wei Nie 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2018年第2期407-420,共14页
Background: The poultry industry is in need of effective antibiotic alternatives to control outbreaks of necrotic enteritis(NE) due to Clostridium perfringens.Methods: This study was conducted to investigate the effec... Background: The poultry industry is in need of effective antibiotic alternatives to control outbreaks of necrotic enteritis(NE) due to Clostridium perfringens.Methods: This study was conducted to investigate the effects of feeding Bacil us coagulans on the growth performance and gut health of broiler chickens with C. perfringens-induced NE. Two hundred and forty 1-day-old broiler chicks were randomly assigned to a 2 × 2 factorial arrangement with two dietary B. coagulans levels(0 or 4 × 109 CFU/kg of diet) and two disease chal enge statuses(control or NE chal enged).Results: NE-induced reduction in body weight gain was relieved by the addition of B. coagulans into broiler diets compared with the NE-infected birds. NE infection damaged intestinal morphological structure, promoted intestinal C.perfringens growth and liver invasion, and enhanced anti-C. perfringens specific sI gA concentrations in the gut and specific IgG levels in serum compared with the uninfected birds. NE infection significantly(P < 0.05) decreased mucin-2(at 14 d post-infection(DPI), tol-like receptor 2(TLR2, at 7 and 14 DPI), TLR4(at 7 and 14 DPI), tumor necrosis factor super family15(TNFSF15, at 7 and 14 DPI), lysozyme(LYZ, at 14 DPI) and fowlicidin-2(at 7 and 14 DPI) mR NA levels, whereas it dramatical y(P = 0.001) increased IFN-γ mR NA levels at 7 DPI. However, chal enged birds fed diets supplemented with B.coagulans showed a significant(P < 0.01) decrease in gut lesion scores, decreased C. perfringens numbers in the cecum and liver, and an increase in fowlicidin-2 mR NA levels in compared with the uninfected birds. In addition, compared with the non-supplemented group, dietary inclusion of B. coagulans improved intestinal barrier structure, further increased specific sI gA levels and alkaline phosphatase(IAP) activity in the jejunum, enhanced the expression of jejunum lysozyme mR NA, and inhibited the growth, colonization, and invasion of C. perfringens; in contrast, it reduced serum-specific IgG concentrations and jejunum IFN-γ mR NA 展开更多
关键词 BACILLUS coagulans BROILER CHICKENS CLOSTRIDIUM perfringens GUT HEALTH
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Structural basis of SARS-CoV-2 3CL^pro and anti-COVID-19 drug discovery from medicinal plants 被引量:32
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作者 muhammad Tahir ul Qamar Safar MAlqahtani +1 位作者 Mubarak AAlamri Ling-Ling Chen 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2020年第4期313-319,共7页
The recent pandemic of coronavirus disease 2019(COVID-19)caused by SARS-CoV-2 has raised global health concerns.The viral 3-chymotrypsin-like cysteine protease(3CL^pro)enzyme controls coronavirus replication and is es... The recent pandemic of coronavirus disease 2019(COVID-19)caused by SARS-CoV-2 has raised global health concerns.The viral 3-chymotrypsin-like cysteine protease(3CL^pro)enzyme controls coronavirus replication and is essential for its life cycle.3CL^pro is a proven drug discovery target in the case of severe acute respiratory syndrome coronavirus(SARS-CoV)and Middle East respiratory syndrome coronavirus(MERS-CoV).Recent studies revealed that the genome sequence of SARS-CoV-2 is very similar to that of SARS-CoV.Therefore,herein,we analysed the 3CL^pro sequence,constructed its 3D homology model,and screened it against a medicinal plant library containing 32,297 potential anti-viral phytochemicals/traditional Chinese medicinal compounds.Our analyses revealed that the top nine hits might serve as potential anti-SARS-CoV-2 lead molecules for further optimisation and drug development process to combat COVID-19. 展开更多
关键词 CORONAVIRUS SARS-CoV-2 COVID-19 Natural products Protein homology modelling Molecular docking Molecular dynamics simulation
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Crosstalk of liver immune cells and cell death mechanisms in different murine models of liver injury and its clinical relevance 被引量:28
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作者 Hilal Ahmad Khan muhammad Zishan Ahmad +1 位作者 Junaid Ali Khan muhammad Imran Arshad 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2017年第3期245-256,共12页
BACKGROUND: Liver inflammation or hepatitis is a result of pluripotent interactions of cell death molecules, cytokines, chemokines and the resident immune cells collectively called as microenvironment. The interplay ... BACKGROUND: Liver inflammation or hepatitis is a result of pluripotent interactions of cell death molecules, cytokines, chemokines and the resident immune cells collectively called as microenvironment. The interplay of these inflammatory mediators and switching of immune responses during hepatotoxic, viral, drug-induced and immune cell-mediated hepatitis decide the fate of liver pathology. The present review aimed to describe the mechanisms of liver injury, its relevance to human liver pathology and insights for the future therapeutic interventions.DATA SOURCES: The data of mouse hepatic models and rele- vant human liver diseases presented in this review are system- atically collected from PubMed, ScienceDirect and the Web of Science databases published in English. RESULTS: The hepatotoxic liver injury in mice induced by the metabolites of CC14, acetaminophen or alcohol represent ne- crotic cell death with activation of cytochrome pathway, for- mation of reactive oxygen species (ROS) and mitochondrial damage. The Fas or TNF-a induced apoptotic liver injury was dependent on activation of caspases, release of cytochrome c and apoptosome formation. The ConA-hepatitis demonstrat- ed the involvement of TRAIL-dependent necrotic/necroptotic cell death with activation of RIPK1/3. The a-GalCer-induced liver injury was mediated by TNF-a. The LPS-induced hepatitis involved TNF-a, Fas/FasL, and perforin/granzyme cell death pathways. The MHV3 or Poly(I:C) induced liver injury was mediated by natural killer cells and TNF-a signaling. The necrotic ischemia-reperfusion liver injury was mediated by hypoxia, ROS, and pro-inflammatory cytokines; however, necroptotic cell death was found in partial hepatectomy. The crucial role of immune ceils and cell death mediators in viral hepatitis (HBV, HCV), drug-induced liver injury, non-alcohol- ic fatty liver disease and alcoholic liver disease in human were discussed. CONCLUSIONS: The mouse animal models of hepatitis provide a parallel approach for the study of human 展开更多
关键词 liver immunobiology HEPATITIS THERAPY mode of cell death
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Biochemical and microbial properties of rhizospheres under maize/ peanut intercropping 被引量:30
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作者 LI Qi-song 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第1期101-110,共10页
Maize/peanut intercropping system shows the significant yield advantage. Soil microbes play major roles in soil nutrient cycling and were affected by intercropping plants. This experiment was carried out to evaluate t... Maize/peanut intercropping system shows the significant yield advantage. Soil microbes play major roles in soil nutrient cycling and were affected by intercropping plants. This experiment was carried out to evaluate the changing of rhizosphere microbial community composition, and the relationship between microbial community and soil enzymatic activities, soil nutrients in maize/peanut intercropping system under the following three treatments: maize (Zea mays L.) and peanut (Arachis hypogaea L.) were intercropped without any separation (NS), by half separation (HS) using a nylon net (50 μm) and complete separation (CS) by using a plastic sheet, respectively. The soil microbial communities were assessed by phospholipid fatty acid (PLFA). We found that soil available nutrients (available nitrogen (Avail N) and available phosphorus (Avail P)) and enzymatic activities (soil urase and phosphomonoesterase) in both crops were improved in NS and HS treatments as compared to CS. Both bacterial and fungal biomasses in both crops were increased in NS followed by HS. Furthermore, Gram-positive bacteria (G+) in maize soils were significant higher in NS and HS than CS, while the Gram-negative (G-) was significant higher in peanut soil. The ratio of normal saturated to monounsaturated PLFAs was significantly higher in rhizosphere of peanut under CS treatment than in any other treatments, which is an indicator of nutrient stress. Redundancy analysis and cluster analysis of PLFA showed rhizospheric microbial community of NS and HS of both plants tended to be consistent. The urase and Avail N were higher in NS and HS of both plants and positively correlated with bacteria, fungi (F) and total PLFAs, while negatively correlated with G+/G- and NS/MS. The findings suggest that belowground interactions in maize/peanut intercropping system play important roles in changing the soil microbial composition and the dominant microbial species, which was closely related with the imp 展开更多
关键词 maize/peanut intercropping phospholipid fatty acid soil nutrient soil enzymes
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慢性乙型肝炎患者肝脏良性占位的发病率及其特点:基于39450例彩色多普勒超声的病例对照研究 被引量:27
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作者 任彦瑜 袁国盛 +8 位作者 周宇辰 胡承光 刘俊维 muhammad Ikram ANWAR 唐淬蓉 李园 于文轩 周元平 戴琳 《南方医科大学学报》 CAS CSCD 北大核心 2019年第10期1149-1154,共6页
目的调查慢性乙型肝炎(CHB)患者中肝脏良性占位性病变的发病率,以普通人群为对照,分析其高发的风险因素及其与小肝癌的鉴别要点。方法回顾性分析2016年1月~2017年12月于南方医院肝脏中心就诊的17 721例CHB患者的影像学资料及相关临床资... 目的调查慢性乙型肝炎(CHB)患者中肝脏良性占位性病变的发病率,以普通人群为对照,分析其高发的风险因素及其与小肝癌的鉴别要点。方法回顾性分析2016年1月~2017年12月于南方医院肝脏中心就诊的17 721例CHB患者的影像学资料及相关临床资料,与同期在南方医院健康管理中心行常规体检的21629例普通人群进行比较分析。结果与普通人群相比,CHB患者的肝囊肿、肝血管瘤、肝硬化结节发病率更高,局灶性结节性增生的发病率更低(分别为11.8%vs 8.7%、8.2%vs 1.6%、20.6%vs 2.4%、0.006%vs 0.042%,均P<0.05),肝细胞腺瘤的发病率无统计学差异(P>0.05)。肝囊肿和肝硬化结节的发病率随年龄增长而升高,其中男性发病率高于女性(P<0.001);肝血管瘤的发病率在30~49岁患者中最高,无性别差异(P>0.05)。肝脏良性占位的超声表现多为内部回声均匀,边界清晰,形态规则:肝血管瘤常为高回声(83.32%,1579/1895),与小肝癌相比,它的四周与内部血流信号较少,固有动脉流速更低,门静脉流速更高;肝硬化结节多为强、弱混合回声(79.60%,7637/9595),结节内部和周边无血流信号,当其体积增大,伴内部回声发生不均匀改变时,提示恶变概率升高;肝囊肿常表现为内部无回声,后方回声增强。结论CHB患者较普通人群更易发生肝囊肿、肝血管瘤和肝硬化结节;其发病率与年龄、性别相关。本研究总结的肝脏良、恶性占位,特别是肝硬化结节的超声声学和血流学特征,能够为早期识别肝脏占位的性质提供重要线索和依据。 展开更多
关键词 肝脏良性占位 慢性乙型病毒性肝炎 发病率
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仿鼹鼠足趾排列的旋耕-秸秆粉碎锯齿刀片设计与试验 被引量:29
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作者 郭俊 张庆怡 +2 位作者 muhammad Sohail Memon 姬长英 赵正 《农业工程学报》 EI CAS CSCD 北大核心 2017年第6期43-50,共8页
随着保护性耕作的不断发展,实际作业中对旋耕刀性能要求愈发严格,该文在国标旋耕刀基础上,将正、侧切削刃上设计成锯齿状,然后考察实际作业过程中功耗、受力以及作业质量,检测仿鼹鼠足趾排列的旋耕-秸秆粉碎锯齿刀片的田间作业功耗和作... 随着保护性耕作的不断发展,实际作业中对旋耕刀性能要求愈发严格,该文在国标旋耕刀基础上,将正、侧切削刃上设计成锯齿状,然后考察实际作业过程中功耗、受力以及作业质量,检测仿鼹鼠足趾排列的旋耕-秸秆粉碎锯齿刀片的田间作业功耗和作业质量。针对该锯齿刀片和国标旋耕刀片在有秸秆颗粒和无秸秆颗粒下进行仿真分析,对比可知:在有秸秆颗粒下,由于刀具要与秸秆接触并发生挤压和剪切作用,从而导致受力以及扭矩值较大。结合理论分析,利用扭矩传感器对仿生锯齿刀和国标旋耕刀进行田间试验。根据0.5 m×0.5 m地表设置不同质量秸秆,分别为0、0.375和0.75 kg(0%、50%、100%),测定拖拉机输出扭矩以及功耗,并依照国标测试方法测定作业质量。田间试验得到扭矩与仿真变化趋势一致。当地表无秸秆和地表含50%秸秆时,锯齿刀片扭矩分别为404.05和438.33 N·m;国标旋耕刀片上扭矩分别为389.27和443.79 N·m。当地表秸秆质量分数为100%时,锯齿刀和国标旋耕刀片上扭矩分别为557.92和507.34 N·m。耕作后地表秸秆和土壤评价结果显示:不同质量含量秸秆覆盖下,仿生锯齿刀耕作后的秸秆掩埋率、土壤破碎率、长度≤15 cm秸秆比例等方面都优于国标旋耕刀。田间试验和仿真结果都显示当地表覆盖秸秆量为0%和100%时,仿生锯齿刀的扭矩高于国标旋耕刀。虽然仿生锯齿刀只在秸秆覆盖量为50%时扭矩与功耗优于国标旋耕刀,但在3种秸秆覆盖量下仿生锯齿刀的耕后地表质量都明显优于国标旋耕刀。综上考虑,在实际作业中,可适当收集田间秸秆。该研究为实现只应用一种刀片来完成旋耕和秸秆粉碎2种不同作业目标提供了参考。 展开更多
关键词 农业机械 仿生 扭矩 锯齿刀 旋耕刀 离散元仿真 作业质量
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中巴喀喇昆仑公路冰川地貌地质灾害 被引量:28
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作者 朱颖彦 杨志全 +5 位作者 廖丽萍 Steve Zou muhammad Waseem 叶成银 陈海鹏 庞明 《灾害学》 CSCD 北大核心 2014年第3期81-90,共10页
中巴喀喇昆仑公路(简称中巴公路)所处高山峡谷冰川地带,区域构造复杂、地势险峻、气候多变、冰川活跃,地形、地质与水文等工程地质条件极其恶劣,公路沿线雪崩、泥石流、坍方、滑坡、岩崩等冰川成因的地质灾害频发。自1979年通车以来,中... 中巴喀喇昆仑公路(简称中巴公路)所处高山峡谷冰川地带,区域构造复杂、地势险峻、气候多变、冰川活跃,地形、地质与水文等工程地质条件极其恶劣,公路沿线雪崩、泥石流、坍方、滑坡、岩崩等冰川成因的地质灾害频发。自1979年通车以来,中巴公路地质病害严重,处于半年通行状态。中巴公路改扩建项目(雷科特大桥-红其拉甫山口)2008年动工,由中国政府援建,将着眼于改善行车路况和地质灾害治理。由于地缘政治与科研条件的限制,国际上对中国公路沿线地质灾害研究并不多见。该文总结5年野外工作成果和资料,尝试对中巴公路地质灾害发育背景、类型、分布规律和发育特征等方面提供总结与评估。 展开更多
关键词 中巴公路 地质灾害 灾害背景 分布 特征
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Meta-analysis of laparoscopic vs open liver resection for hepatocellular carcinoma 被引量:27
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作者 Jun-Jie Xiong Kiran Altaf +6 位作者 muhammad A Javed Wei Huang Rajarshi Mukherjee Gang Mai Robert Sutton Xu-Bao Liu Wei-Ming Hu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第45期6657-6668,共12页
AIM:To conduct a meta-analysis to determine the safety and efficacy of laparoscopic liver resection(LLR) and open liver resection(OLR) for hepatocellular carcinoma(HCC).METHODS:PubMed(Medline),EMBASE and Science Citat... AIM:To conduct a meta-analysis to determine the safety and efficacy of laparoscopic liver resection(LLR) and open liver resection(OLR) for hepatocellular carcinoma(HCC).METHODS:PubMed(Medline),EMBASE and Science Citation Index Expanded and Cochrane Central Register of Controlled Trials in the Cochrane Library were searched systematically to identify relevant comparative studies reporting outcomes for both LLR and OLR for HCC between January 1992 and February 2012.Two authors independently assessed the trials for inclusion and extracted the data.Meta-analysis was performed using Review Manager Version 5.0 software(The Cochrane Collaboration,Oxford,United Kingdom).Pooled odds ratios(OR) or weighted mean differences(WMD) with 95%CI were calculated using either fixed effects(Mantel-Haenszel method) or random effects models(DerSimonian and Laird method).Evaluated endpoints were operative outcomes(operation time,intraoperative blood loss,blood transfusion requirement),postoperative outcomes(liver failure,cirrhotic decompensation/ascites,bile leakage,postoperative bleeding,pulmonary complications,intraabdominal abscess,mortality,hospital stay and oncologic outcomes(positive resection margins and tumor recurrence).RESULTS:Fifteen eligible non-randomized studies were identified,out of which,9 high-quality studies involving 550 patients were included,with 234 patients in the LLR group and 316 patients in the OLR group.LLR was associated with significantly lower intraoperative blood loss,based on six studies with 333 patients [WMD:-129.48 mL;95%CI:-224.76-(-34.21) mL;P = 0.008].Seven studies involving 416 patients were included to assess blood transfusion requirement between the two groups.The LLR group had lower blood transfusion requirement(OR:0.49;95%CI:0.26-0.91;P = 0.02).While analyzing hospital stay,six studies with 333 patients were included.Patients in the LLR group were found to have shorter hospital stay [WMD:-3.19 d;95%CI:-4.09-(-2.28) d;P < 0.00001] than their OLR counterpart.Seven studies including 416 patients 展开更多
关键词 Hepatocellular carcinoma LAPAROSCOPY Open liver resection HEPATECTOMY META-ANALYSIS
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中巴公路泥石流灾害破坏及防治优化 被引量:26
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作者 廖丽萍 朱颖彦 +6 位作者 杨志全 muhammad Waseem Steve Zou 陈济丁 王云 叶成银 张学进 《地质科技情报》 CAS CSCD 北大核心 2013年第6期168-174,共7页
中巴公路沿线活跃的地质构造运动、陡峭的地形地貌与冰川气候造成泥石流广泛发育,威胁中巴公路扩建与建成后的运营。分布在中巴公路北段冰川泥石流对该公路的威胁最为严重。根据2008-2011年期间雨季前后泥石流的活动状况,采用沿线普查... 中巴公路沿线活跃的地质构造运动、陡峭的地形地貌与冰川气候造成泥石流广泛发育,威胁中巴公路扩建与建成后的运营。分布在中巴公路北段冰川泥石流对该公路的威胁最为严重。根据2008-2011年期间雨季前后泥石流的活动状况,采用沿线普查与重点详查的研究方式,总结中巴公路沿线泥石流灾害的主要危害类型;并结合设计图纸,对2009年以前原中巴公路防治工程进行简要的损毁评估;通过分析中巴公路的防治现状提出相应的防治对策,最终针对典型的病害提出具有代表性的改进措施,以期为高海拔区公路灾害的防治提供一定的参考。研究表明:中巴公路泥石流的危害类型有5种,即淤积、侵蚀、冲击、漫流改道与堵江;损毁评估结果显示原有小型泥石流防治工程基本失效;原大型桥梁工程配套防治工程需要新建或加固;而新建桥梁工程运行良好;泥石流防治工程应考虑以下5个现状:援建工程的性质、不良工程地质条件、公路短期安全与灾害发展趋势的统一、主动工程被动防治及建立灾害管理与公路养护机构;鉴于中巴公路防治工程所面临的"技术经济性"问题,典型防治工程应根据泥石流的分布特征、性质特点与公路的交汇关系,采取因地制宜的防治方案。 展开更多
关键词 中巴公路 泥石流 病害 防治
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