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大型无人直升机电力线路智能巡检宽带卫星通信系统 被引量:38
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作者 彭向阳 王柯 +3 位作者 肖祥 吴开春 包令聪 顾温国 《高电压技术》 EI CAS CSCD 北大核心 2019年第2期368-376,共9页
大型无人直升机载荷能力强、续航时间长,可满足长距离输电线路巡检需求,是无人机电力巡检重要研究和应用方向,但目前通信问题制约着无人机的巡检应用。在国内首次采用卫星中继通信技术解决大型无人直升机电力巡检通信问题,分析了无人机... 大型无人直升机载荷能力强、续航时间长,可满足长距离输电线路巡检需求,是无人机电力巡检重要研究和应用方向,但目前通信问题制约着无人机的巡检应用。在国内首次采用卫星中继通信技术解决大型无人直升机电力巡检通信问题,分析了无人机卫星通信若干关键技术需求,基于Z5型国产大型无人机平台完成宽带卫星通信系统研制,采用机载调制解调器突发通信模式防止无人机旋翼遮挡天线信号;同时介绍了系统调试中发现的问题和解决方法,经过设计、生产、试验和试飞等阶段,验证了系统的功能和性能。研制的机载卫通系统质量小于16 kg,机载天线直径0.3 m,开展了20余回110~500kV带电线路巡检试验和应用,无人机单架次最大巡检线路长度超过30 km,卫通系统达到了设计目标,无人机超低空、超视距巡检作业不受复杂地域条件限制。 展开更多
关键词 大型无人直升机 超视距 超低空 电力线路 智能巡检 宽带卫星通信系统 旋翼遮挡 中继通信
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CD147-spike protein is a novel route for SARS-CoV-2 infection to host cells 被引量:37
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作者 ke Wang Wei Chen +42 位作者 Zheng Zhang Yongqiang Deng Jian-Qi Lian Peng Du Ding Wei Yang Zhang Xiu-Xuan Sun Li Gong Xu Yang Lei He Lei Zhang Zhiwei Yang Jie-Jie Geng Ruo Chen Hai Zhang Bin Wang Yu-Meng Zhu Gang Nan Jian-Li Jiang Ling Li Jiao Wu Peng Lin Wan Huang Liangzhi Xie Zhao-Hui Zheng Kui Zhang Jin-Lin Miao Hong-Yong Cui Min Huang Jun Zhang Ling Fu xiang-Min Yang Zhongpeng Zhao Shihui Sun Hongjing Gu Zhe Wang Chun-Fu Wang Yacheng Lu Ying-Ying Liu Qing-Yi Wang Huijie Bian Ping Zhu Zhi-Nan Chen 《Signal Transduction and Targeted Therapy》 SCIE CSCD 2020年第1期162-171,共10页
In face of the everlasting battle toward COVID-19 and the rapid evolution of SARS-CoV-2,no specific and effective drugs for treating this disease have been reported until today.Angiotensin-converting enzyme 2(ACE2),a ... In face of the everlasting battle toward COVID-19 and the rapid evolution of SARS-CoV-2,no specific and effective drugs for treating this disease have been reported until today.Angiotensin-converting enzyme 2(ACE2),a receptor of SARS-CoV-2,mediates the virus infection by binding to spike protein.Although ACE2 is expressed in the lung,kidney,and intestine,its expressing levels are rather low,especially in the lung.Considering the great infectivity of COVID-19,we speculate that SARS-CoV-2 may depend on other routes to facilitate its infection.Here,we first discover an interaction between host cell receptor CD147 and SARS-CoV-2 spike protein.The loss of CD147 or blocking CD147 in Vero E6 and BEAS-2B cell lines by anti-CD147 antibody,Meplazumab,inhibits SARSCoV-2 amplification.Expression of human CD147 allows virus entry into non-susceptible BHK-21 cells,which can be neutralized by CD147 extracellular fragment.Viral loads are detectable in the lungs of human CD147(hCD147)mice infected with SARS-CoV-2,but not in those of virus-infected wild type mice.Interestingly,virions are observed in lymphocytes of lung tissue from a COVID-19 patient.Human T cells with a property of ACE2 natural deficiency can be infected with SARS-CoV-2 pseudovirus in a dosedependent manner,which is specifically inhibited by Meplazumab.Furthermore,CD147 mediates virus entering host cells by endocytosis.Together,our study reveals a novel virus entry route,CD147-spike protein,which provides an important target for developing specific and effective drug against COVID-19. 展开更多
关键词 ACE2 CD147 INTESTINE
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煤矿井下自动化钻机研发关键技术 被引量:36
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作者 张锐 姚克 +7 位作者 方鹏 王龙鹏 陈逢雷 陈翔 邵俊杰 罗鹏平 王松 刘祺 《煤炭科学技术》 CAS CSCD 北大核心 2019年第5期59-63,共5页
针对煤矿井下钻机以液压传动、功能实现为主的不足,结合未来钻孔施工"机械化换人,自动化减人"的需求,提出了采用整体式履带布局的自动化井下坑道钻机的设计思路,制定了钻机总体结构与方案,研制了主动钻杆式无卡盘回转器、夹... 针对煤矿井下钻机以液压传动、功能实现为主的不足,结合未来钻孔施工"机械化换人,自动化减人"的需求,提出了采用整体式履带布局的自动化井下坑道钻机的设计思路,制定了钻机总体结构与方案,研制了主动钻杆式无卡盘回转器、夹持卸扣装置、自动调角和可控钻进的给进装置、自动加杆装置等关键执行机构,开发了参数监测系统和多功能电液控制系统。在地面进行了实钻试验,单根钻杆从自动加杆到钻进完成耗时约55 s,单根钻杆自动卸杆耗时约50 s,验证了钻机的技术性能,试验结果表明:自动化钻机性能可靠、功能完善、自动化程度高、工人劳动强度低。 展开更多
关键词 自动化钻进 机械手 电液控制 双夹持器
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Effects of Chinese herbs on multiple ion channels in isolated ventricular myocytes 被引量:30
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作者 LI Ning MA ke-juan +3 位作者 WU xiang-feng SUN Qi ZHANG Yi-hui PU Jie-lin 《Chinese Medical Journal》 SCIE CAS CSCD 2007年第12期1068-1074,共7页
Background Shensong Yangxin (SSYX) is one of the compound recipe of Chinese materia medica. This study was conducted to investigate the effects of SSYX on sodium current (/Na), L-type calcium current (/Ca.L), tr... Background Shensong Yangxin (SSYX) is one of the compound recipe of Chinese materia medica. This study was conducted to investigate the effects of SSYX on sodium current (/Na), L-type calcium current (/Ca.L), transient outward potassium current (/to), delayed rectifier current (/K), and inward rectifier potassium currents (/K1) in isolated ventricular myocytes. Methods Whole cell patch-clamp technique was used to study ion channel currents in enzymatically isolated guinea pig or rat ventricular myocytes. Results SSYX decreased peak Na by (44.84±7.65)% from 27.21±5.35 to 14.88±2..75 pA/pF (n=-5, P〈0.05). The medicine significantly inhibited the /Ca,L. At concentrations of 0.25, 0.50, and 1.00 g/100 ml, the peak/Ca,L was reduced by (19.22±1.10)%, (44.82±6.50)% and (50.69±5.64)%, respectively (n=5, all P〈0.05). SSYX lifted the I-V curve of both /Na and /Ca,L without changing the threshold, peak and reversal potentials. At the concentration of 0.5%, the drug blocked the transient component of /to by 50.60% at membrane voltage of 60 mV and negatively shifted the inactive curve and delayed the recovery from channel inactivation. The tail current density of /K was decreased by (30.77±1.11)% (n=5, P〈0.05) at membrane voltage of 50 mV after exposure to the medicine and the time-dependent activity of /K was also inhibited. Similar to the effect on /K, the SSYX inhibited /K1 by 33.10% at the test potential of -100 mV with little effect on reversal potential and the rectification property. Conclusions The experiments revealed that SSYX could block multiple ion channels such as /Na /Ca,L, /k, /to and /K1, which may change the action potential duration and contribute to some of its antiarrhythmic effects. 展开更多
关键词 ion channels patch clamp antiarrhythmic drugs Shensong Yangxin capsule
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腹腔镜下结直肠癌根治术对老年结直肠癌患者临床疗效和并发症的影响 被引量:32
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作者 安可湘 纪伟 +2 位作者 荆凯 刘国栋 曹飞 《解放军医药杂志》 CAS 2021年第3期34-36,共3页
目的分析腹腔镜下结直肠癌根治术对老年结直肠癌患者临床疗效和并发症的影响。方法选取2018年6月—2019年12月行手术治疗的81例老年结直肠癌患者,根据不同的手术方法分为观察组37例与对照组44例,观察组采用腹腔镜下结直肠癌根治术治疗,... 目的分析腹腔镜下结直肠癌根治术对老年结直肠癌患者临床疗效和并发症的影响。方法选取2018年6月—2019年12月行手术治疗的81例老年结直肠癌患者,根据不同的手术方法分为观察组37例与对照组44例,观察组采用腹腔镜下结直肠癌根治术治疗,对照组采用传统开腹手术治疗。比较2组手术时间、术中出血量、术后下床时间、住院时间、术后胃肠道激素含量、术后肠道排气时间、术后恢复正常进食时间以及术后并发症发生情况。结果观察组手术时间、住院时间显著短于对照组,术中出血量少于对照组,术后下床时间、肠道排气时间、恢复正常进食时间均显著早于对照组,术后胃动素、胃泌素含量显著高于对照组,差异均有统计学意义(P<0.01);观察组的术后并发症总发生率显著低于对照组(P<0.05)。结论腹腔镜下结直肠癌根治术可改善老年结直肠癌患者手术相关指标及术后并发症发生情况,有益于患者的术后恢复。 展开更多
关键词 腹腔镜检查 结直肠肿瘤 结直肠外科手术 胃泌素类 并发症
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Comparison of laparoscopic vs open liver lobectomy(segmentectomy) for hepatocellular carcinoma 被引量:32
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作者 Ben-Shun Hu ke Chen Hua-Min Tan xiang-Ming Ding Jing-Wang Tan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第42期4725-4728,共4页
AIM:To investigate the effects of laparoscopic hepatectomy for the treatment of hepatocellular carcinoma(HCC) .METHODS:From 2006 to January 2011,laparoscopic hepatectomies were performed on 30 cases of HCC at Northern... AIM:To investigate the effects of laparoscopic hepatectomy for the treatment of hepatocellular carcinoma(HCC) .METHODS:From 2006 to January 2011,laparoscopic hepatectomies were performed on 30 cases of HCC at Northern Jiangsu People's Hospital. During this sametime period,30 patients elected to undergo conventional open hepatectomy over laparoscopic hepatectomy at the time of informed consent. The degree of invasiveness and outcomes of laparoscopic hepatectomy compared to open hepatectomy for HCC were evaluated.RESULTS:Both groups presented with similar bloodloss amounts,operating times and complications. Patients in the laparoscopic hepatectomy group started walking and eating significantly earlier than those inthe open hepatectomy group,and these more rapid recoveries allowed for shorter hospitalizations. There were no significant differences between procedures insurvival rate.CONCLUSION:Laparoscopic hepatectomy is beneficial for patient quality of life if the indications are appropriately based on preoperative liver function and the location and size of the HCC. 展开更多
关键词 LAPAROSCOPY Hepatocellular carcinoma Liver resection Liver Iobectomy
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单孔加一孔腹腔镜全胃切除食管空肠π形吻合术治疗胃癌的可行性及初步技术经验 被引量:30
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作者 杜广胜 江恩来 +7 位作者 邱远 王文生 王帅 李云波 彭科 李祥 杨桦 肖卫东 《中华胃肠外科杂志》 CAS CSCD 北大核心 2018年第5期556-563,共8页
目的探索经脐单孔加一孔腹腔镜全胃切除、食管空肠π形吻合术(SILT-π)治疗胃癌的可行性、安全性及初步技术经验。方法回顾性分析2017年8—10月间在陆军军医大学第二附属医院普通外科行SILT-π手术治疗的5例胃癌患者临床资料。取绕脐... 目的探索经脐单孔加一孔腹腔镜全胃切除、食管空肠π形吻合术(SILT-π)治疗胃癌的可行性、安全性及初步技术经验。方法回顾性分析2017年8—10月间在陆军军医大学第二附属医院普通外科行SILT-π手术治疗的5例胃癌患者临床资料。取绕脐弧形2.5~3.0 cm切口,置入单孔腹腔镜装置,包括5 mm Trocar作为镜头孔、主刀左手操作孔及助手操作孔;于左上腹腋前线肋缘下2 cm作1 cm切口,置入12 mm Trocar作为辅助操作孔,用于置入超声刀等能量装置、腔镜下切割闭合器及术后引流管放置。按胃癌D2根治术的操作规程进行淋巴结清扫及病灶切除。在清扫胃周淋巴结并充分游离食管下段后,采用胃预牵拉式食管空肠π形吻合法进行食管空肠侧侧吻合,即首先用消毒线绳绕过贲门胃底部后打结,助手将线绳向左下腹牵拉充分下拉暴露食管下段,于食管右后侧预定离断平面处戳孔打开食管管腔。于Treitz韧带远端40 cm处上提牵拉空肠,评估与食管吻合无张力。于预吻合处打开小肠系膜,离断边缘血管弓,对系膜缘小肠开孔。于左上腹Trocar置入腔镜用切割闭合器后张开钉仓,插入食管及空肠开孔后击发闭合器行食管空肠侧侧吻合。于空肠系膜裂孔后使用腔内闭合器将侧侧吻合共同开口关闭,离断标本。将切口保护套手套去除,关闭气腹后于距食管空肠侧侧吻合口30 cm处行输入端及输出端小肠肠管侧侧吻合。结果5例胃癌患者均为男性,年龄(56.8 ± 8.2)岁,术前临床分期均为cT2~4N0~2M0。5例患者均成功施行SILT-π手术,手术切口长度(2.9 ± 0.2)cm,手术时间(396.0 ± 36.1)min,术中出血量(140.0 ± 66.7)ml。术后病理示,近、远端切缘距离分别为(2.6 ± 1.1)cm和(8.7 ± 2.5)cm,淋巴结清扫数目为(25.8 ± 7.2)枚。术后均按加速康复外科原则处理,术后首次排气时间 展开更多
关键词 胃肿瘤 胃切除术 腹腔镜 单孔加一孔 π形吻合术
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黄河流域煤电基地固废井下绿色充填开采理论与技术 被引量:29
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作者 杨科 魏祯 +3 位作者 赵新元 何祥 张继强 姬健帅 《煤炭学报》 EI CAS CSCD 北大核心 2021年第S02期925-935,共11页
全国14个大型煤炭基地中有9个位于黄河流域,长期以来的煤炭资源持续性高强度开发与利用,造成地表沉陷与固废堆积,已严重影响到黄河流域生态环境的高质量发展。煤矿充填开采是解放“三下一上”压煤,延长矿井服务年限,解决矿区矸石污染生... 全国14个大型煤炭基地中有9个位于黄河流域,长期以来的煤炭资源持续性高强度开发与利用,造成地表沉陷与固废堆积,已严重影响到黄河流域生态环境的高质量发展。煤矿充填开采是解放“三下一上”压煤,延长矿井服务年限,解决矿区矸石污染生态环境问题的重要途径,可有效减轻煤炭开采对自然、社会和生态环境的影响与破坏。针对黄河流域生态脆弱区煤炭开采与生态环境保护的需求,全面调研分析了煤矿充填开采技术发展现状,获得了黄河流域煤电基地矿井充填发展历程及其开采特点。基于此,为充分发挥煤炭基地能源支撑和煤矿开采遗留地下空间的优势,提出黄河流域固废与井下绿色充填开采新模式,结合宁东煤矿、煤电、煤化工产业群发展特点,亟需开展井下煤矸石源头减量与智能分选、固废重金属络合-钝化、功能性多孔吸附材料研发、绿色充填材料制备、固废井下注充开采多场理论等5项基础研究,亟待攻克充填材料远距离安全高效储运充、充填体与围岩协同控顶、充填开采效果监测监控、煤基固废全产业链接协同利用等4项关键技术,构建黄河流域煤炭资源绿色开采和全产业链接清洁利用理论与技术,为实现黄河流域煤电基地固废减量化、资源化、规模化绿色利用与生态环境保护提供可靠技术支持。 展开更多
关键词 绿色开采 黄河流域 煤电基地 固废资源化 生态环境
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基于连通状态矩阵的智能变电站安措校核方法 被引量:27
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作者 高旭 马迎新 +4 位作者 王可 汤翔鹰 江知瀚 高翔 胡炎 《电力自动化设备》 EI CSCD 北大核心 2019年第7期195-202,共8页
智能变电站采用网络通信模式,其二次安措具有操作对象复杂、隐含不直观的缺点,安措票的正确性难以保证。首先基于变电站配置描述(SCD)文件、IED能力描述(ICD)文件和光纤物理回路描述(SPCD)文件等模型文件,建立智能变电站二次设备的静态... 智能变电站采用网络通信模式,其二次安措具有操作对象复杂、隐含不直观的缺点,安措票的正确性难以保证。首先基于变电站配置描述(SCD)文件、IED能力描述(ICD)文件和光纤物理回路描述(SPCD)文件等模型文件,建立智能变电站二次设备的静态拓扑模型,然后读取二次设备的相应状态,进而提出基于二次设备连通状态矩阵的智能变电站安措校核方法。该方法读取安措操作的步骤集合,对安措操作的每一步进行操作校核,检验该操作是否会造成保护的误闭锁或误动作,在操作校核通过后,再进行安措隔离校核,检验检修设备和运行设备之间是否实现了有效隔离。通过某变电站事故和某220kV智能变电站的算例,证明了所提安措校核方法的有效性。 展开更多
关键词 智能变电站 静态拓扑模型 二次安措 连通状态矩阵 操作校核 隔离校核
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Fibroblast growth factor 21 as a possible endogenous factor inhibits apoptosis in cardiac endothelial cells 被引量:27
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作者 Lv Yun LIU Jing-hua +7 位作者 ZHANG Li-ke DU Jie ZENG xiang-jun HAO Gang HUANG Ji ZHAO Dong-hui WANG Guo-zhong ZHANG Ying-chuan 《Chinese Medical Journal》 SCIE CAS CSCD 2010年第23期3417-3421,共5页
Background Fibroblast growth factor 21 (FGF21) is a new member of FGF super family that is an important endogenous regulator for systemic glucose and lipid metabolism. This study aimed to explore whether FGF21 reduc... Background Fibroblast growth factor 21 (FGF21) is a new member of FGF super family that is an important endogenous regulator for systemic glucose and lipid metabolism. This study aimed to explore whether FGF21 reduces atherosclerotic injury and prevents endothelial dysfunction as an independent protection factor.Methods The present study was designed to investigate the changes of FGF21 levels induced by oxidized-low density lipoprotein (ox-LDL), and the changes of apoptosis affected by regulating FGF21 expression. The FGF21 mRNA levels of cultured cardiac microvascular endothelial cells (CMECs) were determined by real time-PCR and the protein concentration in culture media was detected by enzyme-linked immunosorbent assay. We analyzed the different expression levels of untreated controls and CMFCs incubated with ox-LDL, and the changes of CMECs apoptosis initiated by the enhancement or suppression of FGF21 levels.Results The secretion levels of FGF21 mRNA and protein were significantly upregulated in CMECs incubated with ox-LDL. Furthermore, FGF21 levels increased by 200 μmol/L bezafibrate could reduce CMECs apoptosis, and inhibit FGF21 expression by shRNA induced apoptosis (P <0.05).Conclusions FGF21 may be a signal of injured target tissue, and may play physiological roles in improving the endothelial function at an early stage of atherosclerosis and in stopping the development of coronary heart disease. 展开更多
关键词 fibroblast growth factor 21 oxidized-low density lipoprotein ATHEROSCLEROSIS endothelial dysfunction
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基于~1H NMR技术黄芪抗疲劳作用的肌肉代谢组学研究 被引量:26
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作者 张瑞 李科 +4 位作者 李爱平 刘月涛 秦雪梅 张翔 杜冠华 《药学学报》 CAS CSCD 北大核心 2018年第5期782-790,共9页
利用~1H NMR代谢组学技术,探讨黄芪对疲劳大鼠腓肠肌的干预作用。采用"游泳劳损加限制饮食"方式造模,考察黄芪(3、6、12 g·kg^(-1))对大鼠力竭游泳的时间的影响。给药最后一天收集大鼠腓肠肌组织进行1H NMR检测,结合多... 利用~1H NMR代谢组学技术,探讨黄芪对疲劳大鼠腓肠肌的干预作用。采用"游泳劳损加限制饮食"方式造模,考察黄芪(3、6、12 g·kg^(-1))对大鼠力竭游泳的时间的影响。给药最后一天收集大鼠腓肠肌组织进行1H NMR检测,结合多元统计分析探讨黄芪的抗疲劳作用。结果表明黄芪可以显著提高大鼠力竭游泳时间。与空白组相比,模型组大鼠腓肠肌中异亮氨酸、亮氨酸、肌酸、磷酸胆碱、氧化三甲胺、牛磺酸、胍基乙酸、AMP、肌苷、组氨酸、次黄嘌呤、鹅肌肽水平升高,乳酸、丙酮、胆碱、甘磷酸胆碱、甘氨酸、组氨酸水平降低。黄芪干预后,高剂量、中剂量和低剂量分别能显著回调其中6、11、5个生物标志物。代谢组学分析揭示了黄芪中剂量抗疲劳作用相对最好,其机制可能与调控大鼠肌肉中氨基酸代谢有关。 展开更多
关键词 黄芪 抗疲劳 肌肉组织 代谢组学 氨基酸代谢
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脑胶质瘤患者手术前后近期心境障碍的临床研究 被引量:25
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作者 胡齐 周杰 +7 位作者 陈义天 刘艳 明杨 龚科 向伟 李慎杰 王中 陈礼刚 《中华神经外科杂志》 CSCD 北大核心 2018年第6期623-626,共4页
目的 探讨脑胶质瘤患者手术前后近期出现心境障碍的临床特点.方法 回顾性纳入2015年7月至2017年6月西南医科大学附属医院神经外科行手术治疗的76例脑胶质瘤患者,术前2~3d及术后5~7d对所有患者行汉密尔顿抑郁量表(HAMD)、汉密尔顿焦... 目的 探讨脑胶质瘤患者手术前后近期出现心境障碍的临床特点.方法 回顾性纳入2015年7月至2017年6月西南医科大学附属医院神经外科行手术治疗的76例脑胶质瘤患者,术前2~3d及术后5~7d对所有患者行汉密尔顿抑郁量表(HAMD)、汉密尔顿焦虑量表(HAMA)及倍克-拉范森躁狂量表(BRMS)评分.采用多元线性逐步回归方法分析影响脑胶质瘤患者HAMD评分的临床因素.结果 与术前比较,76例脑胶质瘤患者术后HAMD评分显著下降[分别为(13.5±3.2)分、(9.8±1.5)分,t=3.010,P<0.05];术后出现抑郁的患者比例显著下降[分别为42.1%(32/76)、15.8% (12/76),x2=12.795,P<0.01].术后HAMA评分[分别为(10.1±2.8)分、(12.8±4.6)分]及出现焦虑的患者比例[分别为38.2%(29/76)、50.0%(38/76)]均较术前下降,但差异均无统计学意义(均P>0.05).术后BRMS评分[分别为(7.5±2.1)分、(8.7±2.5)分]及出现躁狂的患者比例[分别为2.6%(2/76)、3.9% (3/76)]较术前下降,但差异均无统计学意义(均P>0.05).比较不同病理级别、肿瘤部位及肿瘤侧别的脑胶质瘤患者手术前后HAMD评分,结果显示病理高级别组、额颞叶组及右侧组术后HAMD评分显著低于术前(均P<0.05).多元线性逐步回归分析显示,家庭收入是术前HAMD评分的影响因素(β=-0.573,t=-3.427,P<0.01),且家庭收入高低与术前HAMD评分高低呈负相关.结论 部分脑胶质瘤患者手术前后存在不同程度及类型的心境障碍,抑郁可能与脑胶质瘤的生长部位密切相关,家庭收入是影响术前HAMD评分的独立危险因素. 展开更多
关键词 神经胶质瘤 情绪障碍 神经外科手术
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Anti-inflammatory effect of Diammonium Glycyrrhizinate in a rat model of ulcerative colitis 被引量:23
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作者 Hao Yuan Wan-Sheng Ji +3 位作者 ke-xiang Wu Jian-Xin Jiao Liang-Hua Sun Yong-Tang Feng 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第28期4578-4581,共4页
AIM: To explore the anti-inflammatory mechanism of Diammonium Glycyrrhizinate in a rat model of ulcerative colitis induced by acetic acid. METHODS: Spragur-Dawley female rats were divided into four groups: Diammoni... AIM: To explore the anti-inflammatory mechanism of Diammonium Glycyrrhizinate in a rat model of ulcerative colitis induced by acetic acid. METHODS: Spragur-Dawley female rats were divided into four groups: Diammonium Glycyrrhizinate group, dexamethasone group, acetic acid control and normal control group. Colonic inflammation was evaluated by disease activity index, gross morphologic damage, histological injury and colonic myeloperoxidase activity. Immunohistochemistry was used to detect the expression of NF-κB, TNF-α and ICAM-1 in colonic mucosa. RESULTS: Compared to the acetic acid control, both Diammonium Glycyrrhizinate and dexamethasone showed a significant anti-inflammatory effect (P 〈 0.01). The expression of NF-κB, TNF-α and ICAM-1 in colonic mucosa was significantly lower in the Diammonium Glycyrrhizinate group and dexamethasone group than in the acetic acid group. CONCLUSION: Diammonium Glycyrrhizinate could reduce inflammatory injury in a rat model of ulcerative colitis. This may occur via suppression of NF-κB, TNF-αand ICAM-1 in colonic mucosa. 展开更多
关键词 Ulcerative colitis Diammonium Glycyrrhizinate MECHANISM
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Improved survival ratios correlate with myeloid dendritic cell restoration in acute-on-chronic liver failure patients receiving methylprednisolone therapy 被引量:23
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作者 Juan Zhao Ji-Yuan Zhang +13 位作者 Hong-Wei Yu Yu-Lan He Jing-Jing Zhao Juan Li Yue-ke Zhu Qin-Wei Yao Jin-Huan Wang Hai-Xia Liu Shu-Yun Shi Zheng-Sheng Zou xiang-Sheng Xu Chun-Bao Zhou Fu-Sheng Wang Qing-Hua Meng 《Cellular & Molecular Immunology》 SCIE CAS CSCD 2012年第5期417-422,共6页
Acute-on-chronic liver failure (ACLF) is a severe life-threatening complication. Liver transplantation is the only available therapeutic option; however, several limitations have restricted its use in patients. The ... Acute-on-chronic liver failure (ACLF) is a severe life-threatening complication. Liver transplantation is the only available therapeutic option; however, several limitations have restricted its use in patients. The use of corticosteroids as an optional therapy for ACLF has received a great deal of interest. The rationale behind its use is the possible role of the immune system in initiating and perpetuating hepatic damage. In order to assess the relationship between myeloid dendritic cells (mDCs) and the efficacy of methylprednisolone (MP) treatment for hepatitis B virus (H BV)-associated ACLF patients, we recruited 30 HBV-associated ACLF patients who had received MP treatment at lO-day intervals; 26 patients received conservative medical (CM) management as a control. The functionality of DC subsets was lower in these ACLF patients compared with healthy subjects. In addition, compared with survivors, dead/transplanted patients had lower functional mDC in both groups. Furthermore, a decreased numbers of mDC at baseline was associated with high mortality of ACLF patients. Importantly, MP treatment resulted in a significant decrease in 28-day mortality, and all MP patients exhibited an initial rapid decrease in circulating mDC numbers within 10 days of MP treatment. Subsequently, MP survivors displayed a continuous increase in mDC numbers accompanied by a decrease in total bilirubin levels by more than 30%. However, MP dead/ transplanted patients lacked these sequential responses compared with survivors. This evidence suggests strongly that the higher mDC numbers at baseline and the recovery of mDC number at the end of treatment may represent a prognostic marker for favorable response to corticosteroid treatment in ACLF patients. 展开更多
关键词 acute-on-chronic liver failure METHYLPREDNISOLONE myeloid dendritic cells plasmacytoid dendritic cells
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基于可视化仿真的智能变电站二次安措校核方法 被引量:22
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作者 鲍伟 王可 +3 位作者 高翔 宋杰 曾平 周德生 《电力系统保护与控制》 EI CSCD 北大核心 2018年第24期150-157,共8页
智能变电站采用网络通信模式,其二次安措具有安措对象复杂、隐含不直观的缺点,安措票的正确性难以保证。提出了智能变电站二次安措的校核方法。首先基于SCD文件、ICD文件和SPCD文件,对智能变电站进行仿真建模。然后提出适于计算机处理... 智能变电站采用网络通信模式,其二次安措具有安措对象复杂、隐含不直观的缺点,安措票的正确性难以保证。提出了智能变电站二次安措的校核方法。首先基于SCD文件、ICD文件和SPCD文件,对智能变电站进行仿真建模。然后提出适于计算机处理的安措票形式化描述机制。最后基于Matlab/Simulink平台对安措票进行可视化仿真校核,保证了安措操作对检修设备与运行设备的可靠隔离。某220 kV智能变电站的应用实例证明了安措校核机制的有效性。 展开更多
关键词 智能变电站 SCD模型 二次安措 形式化描述 隔离校核
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多源煤基固废绿色充填基础理论与技术体系 被引量:21
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作者 杨科 赵新元 +1 位作者 何祥 魏祯 《煤炭学报》 EI CAS CSCD 北大核心 2022年第12期4201-4216,共16页
煤炭开采、发电、煤化工等工业中产生的煤基固废存量大、增量多、利用率低已成为制约宁夏宁东基地绿色低碳、高质量发展的瓶颈。井下绿色充填是无害化、资源化、规模化处置利用多源煤基固废的有效途径。以宁夏宁东基地为试验区,分析了... 煤炭开采、发电、煤化工等工业中产生的煤基固废存量大、增量多、利用率低已成为制约宁夏宁东基地绿色低碳、高质量发展的瓶颈。井下绿色充填是无害化、资源化、规模化处置利用多源煤基固废的有效途径。以宁夏宁东基地为试验区,分析了多源煤基固废的污染风险、理化性质和多重属性,系统阐述了煤基固废用于井下充填的基础理论和技术体系。研究表明:(1)煤矸石、粉煤灰、脱硫石膏等污染性和理化性质符合填埋标准(GB 18599—2020),气化渣、炉底渣等固废的部分重金属质量分数超过筛选值,可采取技术措施降低潜在污染风险,多源煤基固废可用于井下绿色充填。(2)煤基固废用于井下充填的基础理论包括绿色充填可行性评价、煤基固废充填材料性能、充填材料与环境多场耦合机理、多层位立体充填机制。(3)多源煤基固废井下绿色充填技术体系主要包括煤矸石源头减量精准开采技术、井下采选充协同技术、煤基固废重金属吸附与络合钝化技术、多源煤基固废充填材料制备技术、充填材料长距离管道输送技术、充填全过程智能监测技术等。最后,根据宁东基地任家庄矿地质条件,提出并实施了超前钻孔注充低位充填,展望了集成活性粉体制备、高值建材研发、生态修复治理、井下绿色充填等煤基固废多产业链接协同利用新模式。 展开更多
关键词 煤基固废 绿色充填开采 协同利用 产业链接 煤电基地
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僵尸网络发展研究 被引量:22
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作者 李可 方滨兴 +1 位作者 崔翔 刘奇旭 《计算机研究与发展》 EI CSCD 北大核心 2016年第10期2189-2206,共18页
僵尸网络(botnet)作为最有效的网络攻击平台,给当今互联网安全带来了巨大威胁.虽然近几年关于僵尸网络的攻防技术研究取得了显著进展,然而,伴随着互联网应用的多元化以及通信技术的不断革新,僵尸网络的形态和命令控制机制也在不断发生变... 僵尸网络(botnet)作为最有效的网络攻击平台,给当今互联网安全带来了巨大威胁.虽然近几年关于僵尸网络的攻防技术研究取得了显著进展,然而,伴随着互联网应用的多元化以及通信技术的不断革新,僵尸网络的形态和命令控制机制也在不断发生变化,这给防御人员带来了新的挑战.深入了解僵尸网络运行机理和发展趋势对有效应对僵尸网络引发的安全威胁具有重要意义.以僵尸网络攻击技术为核心,从形式化定义、传播方式、生命周期、恶意行为、命令控制信道方面对僵尸网络机理进行全面介绍,按时间顺序将僵尸网络的发展历程划分为PC攻击和广泛攻击2个阶段,对各阶段的技术特点、行为特性、代表案例以及演化规律进行详细阐述,总结当今僵尸网络防御方法和研究成果,对已有研究遗留的问题和未来可能研究热点进行讨论. 展开更多
关键词 僵尸网络 命令控制信道 网络对抗 增值网络攻击 综述
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Therapeutic effects of endoscopic therapy combined with enteral nutrition on acute severe biliary pancreatitis 被引量:22
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作者 ZHOU Wen-ce LI Yu-min +6 位作者 ZHANG Hui LI Xun ZHANG Lei MENG Wen-bo ZHU ke-xiang ZHANG Quan-bao HE Min-yan 《Chinese Medical Journal》 SCIE CAS CSCD 2011年第19期2993-2996,共4页
Background Acute severe biliary pancreatitis (ASBP) is a severe and fatal disease, and the expenditure is huge and therapeutic effects are still not satisfactory. This study aimed to improve the therapeutic effects ... Background Acute severe biliary pancreatitis (ASBP) is a severe and fatal disease, and the expenditure is huge and therapeutic effects are still not satisfactory. This study aimed to improve the therapeutic effects and reduce the expenditure of ASBP treatment.Methods One hundred and five patients diagnosed with ASBP were referred to our department from January 2004 to July 2009. Diagnosis was based on the 2007 criteria of the Chinese Society of Surgery. Patients were divided into two groups; the E group: 50 patients who underwent endoscopic retrograde choledochopancreatography (ERCP) + endoscopic sphincterotomy (EST) + endoscopic lithotripsy basket (ESR) +endoscopic retrograde biliary drainage (ERBD)and enteral nutrition (EN), and the R group: 55 patients who underwent traditional treatment without ERCP. Subsequently,subjective symptoms, signs, biochemical analysis, serum endotoxin, tumor necrosis factor a, grades by computed tomography (CT), cost of hospitalization and length of stay were compared between the two groups.Results All enrolled patients complied well with all therapeutic regimens. Endoscopic therapy that combined EN could significantly improve symptoms, clinical signs, laboratory values, tumor necrosis factor a and endotoxin while significantly reducing hospital expenditure and length of hospital stay. The experimental findings revealed that there were obvious advantages in the E group compared with the R group.Conclusions Endoscopic therapy combined with EN is an effective, safe and economic therapeutic regimen of ASBP. 展开更多
关键词 ENDOSCOPY enteral nutrition acute severe biliary pancreatitis therapeutic regimen
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Experimental investigation into stress-relief characteristics with upward large height and upward mining under hard thick roof 被引量:21
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作者 ke Yang xiang He +3 位作者 Litong Dou Wenjun Liu Li Sun Haisong Ye 《International Journal of Coal Science & Technology》 EI 2015年第1期91-96,共6页
According to geological conditions of No. 3 and No. 4 coal seams (namely A3 and B4) of the Pan'er coal mine and the parameters of panels 11223, 11224, and 11124 with fully-mechanical coal mining, we built 2D simila... According to geological conditions of No. 3 and No. 4 coal seams (namely A3 and B4) of the Pan'er coal mine and the parameters of panels 11223, 11224, and 11124 with fully-mechanical coal mining, we built 2D similar material simulation and FLAC3D numerical simulation models to investigate the development of mining-induced stress and the extraction effect of pressure-relief gas with large height and upward mining. Based on a comprehensive analysis of experimental data and observations, we obtained the deformation and breakage characteristics of strata overlying the coal seam, the development patterns of the mining-induced stress and fracture, and the size of the stress-relief area. The stress-relief effect was investigated and analyzed in consideration with mining height and three thick hard strata. Because of the group of three hard thick strata located in the main roof and the residual stress of mined panel 11124, the deformation, breakage, mining-induced stress and fracture development, and the stress-relief coefficient were discontinuous and asymmetrical. The breakage angle of the overlying strata, and the compressive and expansive zones of coal deformation were mainly controlled by the number, thickness, and strength of the hard stratum. Compared with the value of breakage angle derived by the traditional empirical method, the experimental value was lower than the traditional results by 3°-4°below the hard thick strata group, and by 13°-19° above the hard thick strata group. The amount of gas extracted from floor drainage roadway of B4 over 17 months was variable and the amount of gas per month differed considerably, being much smaller when panel 11223 influenced the area of the three hard thick strata. Generally, the stress-relief zone of No. 4 coal seam was small under the influence of the hard thick strata located in the main roof, which played an important role in delaying the breakage time and increasing the breakage space. In this study we gained understanding of the stress-relief mechanism in 展开更多
关键词 Integrated coal exploitation and gas extraction Large mining height Stress-relief effect Hard thick strata Mining-induced stress
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从美国“绿道”到欧洲绿道:城乡空间生态网络构建--以广州市增城区为例 被引量:20
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作者 赵珂 李享 袁南华 《中国园林》 北大核心 2017年第8期82-87,共6页
自广州市增城区践行绿道开始,由慢行道和开敞空间组成的绿道建设在中国大力发展,在为市民提供亲近自然、健康休闲的休憩空间的同时,也带动了农村地区的经济发展。但在增城区的绿道实践过程中,缺乏对自然生态系统的修复与关爱等问题逐渐... 自广州市增城区践行绿道开始,由慢行道和开敞空间组成的绿道建设在中国大力发展,在为市民提供亲近自然、健康休闲的休憩空间的同时,也带动了农村地区的经济发展。但在增城区的绿道实践过程中,缺乏对自然生态系统的修复与关爱等问题逐渐凸显。通过对比美国和欧洲绿道的建设情况,厘清绿道与生态廊道及生态网络的衍生关系,总结出基于生态网络构建的绿道规划方法,为广州市增城区绿道建设注入具有自我维育能力的生态功能,丰富了绿道的形式,为我国生态网络化的绿道建设提供理论与实践探索。 展开更多
关键词 风景园林 城乡空间 绿道 生态廊道 生态网络
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