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我国煤矿巷道围岩控制技术发展70年及展望 被引量:319
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作者 康红普 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2021年第1期1-30,共30页
总结新中国成立70年来,我国煤矿巷道围岩控制领域取得的主要研究成果,涉及巷道围岩地质力学特性,围岩变形、破坏特征与机制,围岩控制理论及技术。介绍煤系沉积岩地层强度、煤岩体结构特征及煤矿井下地应力分布规律,采煤引起的采动应力... 总结新中国成立70年来,我国煤矿巷道围岩控制领域取得的主要研究成果,涉及巷道围岩地质力学特性,围岩变形、破坏特征与机制,围岩控制理论及技术。介绍煤系沉积岩地层强度、煤岩体结构特征及煤矿井下地应力分布规律,采煤引起的采动应力场分布特征及对采动巷道围岩稳定性的影响。指出煤矿巷道围岩变形具有分阶段性、流变性和冲击性,巷道围岩破坏有煤岩破坏、结构面破坏及围岩结构失稳破坏3种模式,软岩、强采动、大变形是我国煤矿巷道围岩控制的主要特点。论述5类巷道围岩控制方法与原理:控制围岩松动载荷、控制围岩变形、在围岩中形成承载结构、围岩改性及围岩卸压。阐述巷道围岩在掘进全过程的控制原理,重点介绍预应力锚杆支护理论及支护应力场的概念。将巷道围岩控制技术分为5类:表面支护、锚固、改性、卸压及联合控制技术,介绍金属支架、锚杆与锚索、注浆加固、水力压裂卸压及联合控制技术的发展历程和应用情况。最后,分析煤矿巷道围岩控制中存在的问题,并展望未来技术发展趋势。 展开更多
关键词 采矿工程 煤矿巷道 围岩控制 采动 支护 改性 卸压
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深部巷道围岩控制的关键技术研究 被引量:161
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作者 侯朝炯 《中国矿业大学学报》 EI CAS CSCD 北大核心 2017年第5期970-978,共9页
针对深部煤炭赋存条件复杂、巷道矿压显现日趋激烈,相当一部分巷道布置在岩石松软、变形剧烈的岩体、煤体或半煤岩体中,深部巷道"失稳"普遍存在的突出难点进行研究.文中阐述了深部巷道围岩控制的两个突出难点:底鼓和蠕变,针... 针对深部煤炭赋存条件复杂、巷道矿压显现日趋激烈,相当一部分巷道布置在岩石松软、变形剧烈的岩体、煤体或半煤岩体中,深部巷道"失稳"普遍存在的突出难点进行研究.文中阐述了深部巷道围岩控制的两个突出难点:底鼓和蠕变,针对性地提出了相应的控制技术——通过加固底板和巷道帮角控制底鼓,采用合理的一次支护和二次支护来实现巷道的长期稳定.研究结果表明:依据深部巷道底鼓的"两点三区"变形特征,底板锚杆、注浆孔深度应深入底板岩层"零位移点"以下,配合帮角加固有效控制深部巷道底鼓;采用合理的一次支护和二次支护保证锚固端提供的径向应力大于巷道蠕变所需的径向应力,使巷道变形速度维持在0.02mm/d左右,保持了巷道围岩的长期稳定并取得良好的效果,对保证深部煤炭资源安全开采具有重大意义. 展开更多
关键词 深部巷道 围岩 底鼓 蠕变 支护 控制技术
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Dysfunction of peripheral blood dendritic cells from patients with chronic hepatitis B virus infection 被引量:131
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作者 Fu-Sheng Wang Li-He Xing Ming-Xu Liu Chuan-Lin Zhu Hui-Gang Liu Hui-Fen Wang Zhou-Yun Lei Division of Biological Engineering,~2 Fourth Department of Liver Diseases,Beijing Institute of Infectious Diseases,Beijing Hospital of Infectious Diseases,Beijing 100039,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第4期537-541,共5页
AIM: To identify the property of dendritic cells (DCs) of peripheral blood monocytes (PBMC) in patients with chronic HBV infection. METHODS: Twenty patients with persistent HBV infection were included in this study, 1... AIM: To identify the property of dendritic cells (DCs) of peripheral blood monocytes (PBMC) in patients with chronic HBV infection. METHODS: Twenty patients with persistent HBV infection were included in this study, 10 healthy subjects being used as a control group. The peripheral blood mononuclear cells (PBMC) of T cell-depleted populations were incubated and induced into mature dendritic cells in the RPMI-1640 medium in the presence of cytokines GM-CSF, IL-4, FLt-3,TNF-alpha and 100mL.L(-1 )of fetal calf serum for a total of 10-12 days. The expressions of surface markers on DCs were evaluated using flow cytometric analysis. ELISA method was used to determine the cytokine levels of interleukin-12 (IL-12) and IL-10 in the supernatant produced by DCs. For detection of the stimulatory capacity of DCs to T cell proliferation, mytomycin C-treated DC were incubated with allogenic T cells. RESULTS: A typical morphology of mature DCs from healthy subjects and HBV-infected patients was induced in in vitro incubation, but the proliferation ability and cellular number of DCs from HBV-infected patients significantly decreased compared with healthy individuals. In particular, the expression levels of HLA-DR, CD80 (B7-1) and CD86 (B7-2) on DC surface from patients were also lower than that from healthy individuals (0.46 vs 0.92 for HLA-DR, 0.44 vs 0.88 for CD80 and 0.44 vs 0.84 for CD86,P【0.05). The stimulatory capacity and production of IL-12 of DCs from patients in allogenic mixed lymphocyte reaction (AMLR) significantly decreased, but the production level of nitric oxide (NO) by DCs simultaneously increased compared with healthy subjects (86 +/- 15 vs 170 +/- 22 micromol.L(-1), P 【0.05). CONCLUSION: The patients with chronic HBV infection have the defective function and immature phenotype of dendritic cells, which may be associated with the inability of efficient presentation of HBV antigens to host immune system for the clearance of HBV. 展开更多
关键词 Adolescent Adult Antigens Surface Cell Division Child Dendritic Cells Female Flow Cytometry Hepatitis B Chronic Humans INTERLEUKIN-10 INTERLEUKIN-12 Male Middle Aged Nitric Oxide Research support Non-U.S. Gov't
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顾桥煤矿深井岩巷破碎软弱围岩支护方法探索 被引量:138
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作者 刘泉声 康永水 白运强 《岩土力学》 EI CAS CSCD 北大核心 2011年第10期3097-3104,共8页
为探索煤矿深井岩巷破碎软弱围岩的支护方法,结合淮南矿业(集团)公司顾桥煤矿-780 m水平南翼轨道大巷的支护工程实践,揭示了深部岩巷的变形规律,并分析了煤矿深部破碎软弱围岩支护的难点及其支护机制,提出顾桥煤矿南翼轨道大巷分步联合... 为探索煤矿深井岩巷破碎软弱围岩的支护方法,结合淮南矿业(集团)公司顾桥煤矿-780 m水平南翼轨道大巷的支护工程实践,揭示了深部岩巷的变形规律,并分析了煤矿深部破碎软弱围岩支护的难点及其支护机制,提出顾桥煤矿南翼轨道大巷分步联合支护的设计理念和优化支护方案。结合围岩表面位移、深部位移等现场监测数据,对新旧支护方案的效果进行了对比,研究结果表明,顾桥煤矿-780 m水平南翼轨道巷采用分步联合支护方法取得了较理想的支护效果。深部岩巷的支护受高地应力、岩体力学性质等因素影响,应结合巷道围岩地质条件采取适当的支护措施,让各种支护手段在时间和空间上实现有效结合,充分发挥并提高围岩的自身承载能力。 展开更多
关键词 深部岩巷 高应力 围岩 支护 监测
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Establishment of cell clones with different metastatic potential from the metastatic hepatocellular carcinoma cell line MHCC97 被引量:111
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作者 Yan Li Zhao-You Tang Sheng-Long Ye Yin-Kun Liu Jie Chen Qiong Xue Jun Chen Dong-Mei Gao Wei-Hua Bao Liver Cancer Institute and Zhongshan Hospital of Fudan University (Former Liver Cancer Institute of Shanghai Medical University),Shanghai 200032,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第5期630-636,共7页
AIM: To establish clone cells with different metastatic potential for the study of metastasis-related mechanisms. METHODS: Cloning procedure was performed on parental hepatocellular carcinoma (HCC) cell line MHCC97, a... AIM: To establish clone cells with different metastatic potential for the study of metastasis-related mechanisms. METHODS: Cloning procedure was performed on parental hepatocellular carcinoma (HCC) cell line MHCC97, and biological characteristics of the target clones selected by in vivo screening were studied. RESULTS: Two clones with high (MHCC97-H) and low (MHCC97-L) metastatic potential were isolated from the parent cell line. Compared with MHCC97-L, MHCC97-H had smaller cell size (average cell diameter 43 microm vs 50 microm) and faster in vitro and in vivo growth rate (tumor cell doubling time was 34.2h vs 60.0h). The main ranges of chromosomes were 55-58 in MHCC97-H and 57-62 in MHCC97-L. Boyden chamber in vitro invasion assay demonstrated that the number of penetrating cells through the artificial basement membrane was (37.5 +/- 11.0) cells/field for MHCC97-H vs (17.7 +/- 6.3)/field for MHCC97-L. The proportions of cells in G0-G1 phase, S phase, and G2-M phase for MHCC97-H/MHCC97-L were 0.56/0.65, 0.28/0.25 and 0.16/0.10, respectively, as measured by flow cytometry. The serum AFP levels in nude mice 5wk after orthotopic implantation of tumor tissue were (246 +/- 66) microg.L(-1) for MHCC97-H and (91 +/- 66) microg.L(-1) for MHCC97-L. The pulmonary metastatic rate was 100% (10/10) vs 40% (4/10). CONCLUSION: Two clones of the same genetic background but with different biological behaviors were established, which could be valuable models for investigation on HCC metastasis. 展开更多
关键词 ALBUMINS Animals Carcinoma Hepatocellular Cell Division Chromosomes Clone Cells Flow Cytometry Hepatitis B Hepatitis B Surface Antigens Hepatitis B virus purification Humans Keratin Liver Liver Neoplasms Experimental Male MICE Mice Inbred BALB C Mice Nude Neoplasm Invasiveness Research support Non-U.S. Gov't Tumor Cells Cultured Virus Integration ALPHA-FETOPROTEINS
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Antitumor activities of human autologous cytokineinduced killer(CIK)cells against hepatocellular carcinoma cells in vitro and in vivo 被引量:107
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作者 Fu-Sheng Wang Ming-Xu Liu Bing Zhang Ming Shi Zhou-Yun Lei Wen-Bing Sun Qing-You Du Ju-Mei Chen,Division of Biological Engineering,Beijing Institute of Infectious Diseases,Beijing 100039,China Wen-Bing Sun,Department of Surgery,Beijing Hospital of Infectious Diseases,Beijing 100039,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第3期464-468,共5页
AIM: To characterize the anticancer function of cytokine-induced killer cells (CIK) and develop an adoptive immunotherapy for the patients with primary hepatocellular carcinoma (HCC), we evaluated the proliferation ra... AIM: To characterize the anticancer function of cytokine-induced killer cells (CIK) and develop an adoptive immunotherapy for the patients with primary hepatocellular carcinoma (HCC), we evaluated the proliferation rate, phenotype and the antitumor activity of human CIK cells from healthy donors and HCC patients in vitro and in vivo. METHODS: Peripheral blood mononuclear cells (PBMC) from healthy donors and patients with primary HCC were incubated in vitro and induced into CIK cells in the presence of various cytokines such as interferon-gamma (IFN-gamma), interleukin-1 (IL-1), IL-2 and monoclonal antibody (mAb) against CD3. The phenotype and characterization of CIK cells were identified by flow cytometric analysis. The cytotoxicity of CIK cells was determined by (51)Cr release assay. RESULTS: The CIK cells were shown to be a heterogeneous population with different cellular phenotypes. The percentage of CD3+/CD56+ positive cells, the dominant effector cells, in total CIK cells from healthy donors and HCC patients, significantly increased from 0.1-0.13% at day 0 to 19.0-20.5% at day 21 incubation, which suggested that the CD3+ CD56+ positive cells proliferated faster than other cell populations of CIK cells in the protocol used in this study. After 28 day in vitro incubation, the CIK cells from patients with HCC and healthy donors increased by more than 300-fold and 500-fold in proliferation cell number, respectively. CIK cells originated from HCC patients possessed a higher in vitro antitumor cytotoxic activity on autologous HCC cells than the autologous lymphokine-activated killer (LAK) cells and PBMC cells. In in vivo animal experiment, CIK cells had stronger effects on the inhibition of tumor growth in Balb/c nude mice bearing BEL-7402-producing tumor than LAK cells (mean inhibitory rate, 84.7% vs 52.8%, P【0.05) or PBMC (mean inhibitory rate, 84.7% vs 37.1%, P【0.01). CONCLUSION: Autologous CIK cells are of highly efficient cytotoxic effector cells against primary hepatocellular carcinoma cells and might 展开更多
关键词 Animals Carcinoma Hepatocellular Cell Division Cytokines Cytotoxicity Immunologic Humans IMMUNOPHENOTYPING Immunotherapy Adoptive Killer Cells Liver Neoplasms MICE Mice Nude Neoplasm Transplantation Research support Non-U.S. Gov't Transplantation Heterologous Tumor Cells Cultured
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HBV cccDNA in patients' sera as an indicator for HBV reactivation and an early signal of liver damage 被引量:108
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作者 Johnny Sze 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第1期82-85,共4页
AIM:To evaluate the covalently closed circle DNA (cccDNA) level of hepatitis B virus (HBV) in patients' liver and sera. METHODS:HBV DNA was isolated from patients' liver biopsies and sera.A sensitive real-time... AIM:To evaluate the covalently closed circle DNA (cccDNA) level of hepatitis B virus (HBV) in patients' liver and sera. METHODS:HBV DNA was isolated from patients' liver biopsies and sera.A sensitive real-time PCR method,which is capable of differentiation of HBV viral genomic DNA and cccDNA,was used to quantify the total HBV cccDNA.The total HBV viral DNA was quantitated by real-time PCR using a HBV diagnostic kit (PG Biotech,LTD,Shenzhen,China) described previously. RESULTS:For the first time,we measured the level of HBV DNA and cccDNA isolated from ten HBV patients' liver biopsies and sera.In the liver biopsies,cccDNA was detected from all the biopsy samples.The copy number of cccDNA ranged from from 0.03 to 173.1 per cell,the copy number of total HBV DNA ranged from 0.08 to 3 717 per cell.The ratio of total HBV DNA to cccDNA ranged from 1 to 3 406.In the sera, cccDNA was only detected from six samples whereas HBV viral DNA was detected from all ten samples.The ratio of cccDNA to total HBV DNA ranged from 0 to 1.77%.To further investigate the reason why cccDNA could only be detected in some patients' sera,we performed longitudinal studies.The cccDNA was detected from the patients' sera with HBV reactivation but not from the patients' sera without HBV reactivation.The level of cccDNA in the sera was correlated with ALT and viral load in the HBV reactivation patients. CONCLUSION:HBV cccDNA is actively transcribed and replicated in some patients' hepatoo/tes,which is reflected by a high ratio of HBV total DNA vs cccDNA.Detection of cccDNA in the liver biopsy will provide an end-point for the anti-HBV therapy.The occurrence of cccDNA in the sera is an early signal of liver damage,which may be another important clinical parameter. 展开更多
关键词 Alanine Transaminase Biopsy DNA Circular DNA Viral Hepatitis B virus Hepatitis B Chronic HEPATOCYTES Humans Kinetics Liver Research support Non-U.S. Gov't Viral Load
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高应力软岩巷道支护失效机制及控制研究 被引量:107
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作者 李为腾 李术才 +3 位作者 玄超 王琦 王新 邵行 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2015年第9期1836-1848,共13页
为明确高应力软岩巷道支护失效机制,并验证新型支护形式的有效性,以赵楼煤矿1 000 m深井为工程背景,在现场监测围岩变形破坏及支护失效规律的基础上,通过对FLAC3D中beam单元的修正处理,实现拱架支护体系的精细化模拟,讨论支护强度等级(... 为明确高应力软岩巷道支护失效机制,并验证新型支护形式的有效性,以赵楼煤矿1 000 m深井为工程背景,在现场监测围岩变形破坏及支护失效规律的基础上,通过对FLAC3D中beam单元的修正处理,实现拱架支护体系的精细化模拟,讨论支护强度等级(拱架形式)、地应力等级、围岩强度等级3个因素对巷道围岩变形量、塑性区范围、支护构件受力状态等的影响规律;在此基础上,分析高应力软岩巷道支护失效机制。对于高应力软岩巷道,锚网喷支护具有明显的局限性;而具有一定刚度和强度的拱架是一种行之有效的围岩控制途径。采用方形钢管约束混凝土拱架支护体系进行现场试验表明,新型高强拱架支护方式使得巷道围岩稳定性得到有效控制。 展开更多
关键词 采矿工程 高应力 软岩巷道 支护 失效机制
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Function of apoptosis and expression of the proteins Bcl-2,p53 and C-myc in the development of gastric cancer 被引量:91
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作者 An Gao Xu Shao Guang Li Ji Hong Liu Ai Hua Gan Research Laboratory of Digestive Disease,Huizhou Central People’s Hospital,Huizhou 516001,Guangdong Province,ChinaDr.An Gao Xu graduated from Guangdong Medical College in 1984.He is an associate physician-in-chief,specializing in the research and treatment of gastrointestinal and liver tumors.He has published 24 papers and 1 book. 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第3期403-406,共4页
INTRODUCTIONIn China ,the incidence and mortality of gastric cancer rank the second among all cancers. Recent development of cancer [1-20].The aim of this study was investigat the insight of apoptosis and bcl-2, p53 a... INTRODUCTIONIn China ,the incidence and mortality of gastric cancer rank the second among all cancers. Recent development of cancer [1-20].The aim of this study was investigat the insight of apoptosis and bcl-2, p53 and C-myc protein expression in the development of gastric cancer . 展开更多
关键词 APOPTOSIS FEMALE Humans Male Middle Aged Precancerous Conditions Proto-Oncogene Proteins c-bcl-2 Proto-Oncogene Proteins c-myc Research support Non-U.S. Gov't Stomach Neoplasms Tumor Suppressor Protein p53
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组织支持感对研发人员创新行为的影响机制研究 被引量:104
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作者 顾远东 周文莉 彭纪生 《管理科学》 CSSCI 北大核心 2014年第1期109-119,共11页
研发人员的创造力是企业技术进步的重要源泉。基于组织支持感理论,从认知和情绪视角,将创造力效能感和积极情绪引入到组织支持感与研发人员创新行为的关系分析框架中,构建组织支持感→创造力效能感/积极情绪→研发人员创新行为理论模型... 研发人员的创造力是企业技术进步的重要源泉。基于组织支持感理论,从认知和情绪视角,将创造力效能感和积极情绪引入到组织支持感与研发人员创新行为的关系分析框架中,构建组织支持感→创造力效能感/积极情绪→研发人员创新行为理论模型,采用自填问卷法调查248名研发人员,在检验同源方差和问卷信效度的基础上,通过结构方程建模方法检验理论模型及相应的研究假设。研究结果表明,①在中国情境下,组织支持感对研发人员创新行为有显著正向影响,组织支持感及其各维度对研发人员创新行为有预测力,其中主管支持的预测力最强;②创造力效能感对研发人员创新行为有显著正向影响,并在组织支持感与研发人员创新行为间起部分中介作用;③积极情绪对研发人员创新行为有显著正向影响,在组织支持感与研发人员创新行为间起部分中介作用;④将创造力效能感和积极情绪同时并入中介模型后,两者的中介作用完全解释了组织支持感对研发人员创新行为的影响。 展开更多
关键词 研发人员 组织支持感 创新行为 创造力效能感 积极情绪 PERCEIVED ORGANIZATIONAL support ( POS)
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地下圆形隧道围岩稳定性的粘弹性力学分析 被引量:33
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作者 朱素平 周楚良 《同济大学学报(自然科学版)》 EI CAS CSCD 1994年第3期329-333,共5页
根据有关岩石力学试验结果,提出了以对数函数描述岩石蠕变的本构模型.借此对地下圆形隧道围岩稳定性进行了力学分析,探讨了人工支护结构与围岩相互作用的关系,导出了描述其变化规律的特征方程,由此而得出了一些有益的结论.
关键词 地下圆形遂道 围岩 稳定性 粘弹性
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采场支架与围岩耦合作用机理研究 被引量:73
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作者 钱鸣高 缪协兴 +1 位作者 何富连 刘长友 《煤炭学报》 EI CAS CSCD 北大核心 1996年第1期40-44,共5页
从研究采场支架受力特点出发,将支架与围岩视为有机的整体,深入分析了它们之间的耦合作用,认为老顶断裂后形成的给定变形与支架作用力无关,而与采空区处理方法及采高等有关,支架承受的给定变形压力则与直接顶的整体力学性能有关,... 从研究采场支架受力特点出发,将支架与围岩视为有机的整体,深入分析了它们之间的耦合作用,认为老顶断裂后形成的给定变形与支架作用力无关,而与采空区处理方法及采高等有关,支架承受的给定变形压力则与直接顶的整体力学性能有关,并反比于直接顶(含顶煤)厚度∑h.从而在理论上进一步揭示了支架工作阻力与顶板下沉量之间的耦合关系。 展开更多
关键词 砌体梁 动架 围岩 双曲线 耦合作用
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Multimodality treatment in hepatocellular carcinoma patients with tumor thrombi in portal vein 被引量:80
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作者 Jia Fan Zhi Quan Wu +5 位作者 Zhao You Tang Jian Zhou Shuang Jian Qiu Zeng Chen Ma Xin Da Zhou Sheng Long Ye Liver Cancer Institute, Zhongshan Hospital, Fudan University Medical Center (Former Shanghai University), 136 Yixueyuan Road, Shanghai 200032, China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第1期28-32,共5页
AIM: To compare the therapeutic effect and significances of multimodality treatment for hepatocellular carcinoma (HCC) with tumor thrombi in portal vein (PVTT). METHODS: HCC patients (n=147) with tumor thrombi in the ... AIM: To compare the therapeutic effect and significances of multimodality treatment for hepatocellular carcinoma (HCC) with tumor thrombi in portal vein (PVTT). METHODS: HCC patients (n=147) with tumor thrombi in the main portal vein or the first branch of portal vein were divided into four groups by the several therapeutic methods. There were conservative treatment group in 18 out of patients (group A); and hepatic artery ligation(HAL) and/or hepatic artery infusion (HAI) group in 18 patients (group B), in whom postoperative chemoembolization was done periodically; group of removal of HCC with PVTT in 79 (group C) and group of transcatheter hepatic arterial chemoembolization (TACE) or HAI and/or portal vein infusion (PVI) after operation in 32 (group D). RESULTS: The median survival period was 12 months in our series and the 1-,3-, and 5-year survival rates were 44.3%, 24.5% and 15.2%, respectively. The median survival times were 2, 5, 12 and 16 months in group A, B, C and D, respectively. The 1-, 3- and 5-year survival rates were 5.6%, 0% and 0% in group A; 22.2%, 5.6% and 0% in group B; 53.9%, 26.9% and 16.6% in group C; 79.3%, 38.9% and 26.8% in group D, respectively. Significant difference appeared in the survival rates among the groups (P 【 0.05). CONCLUSION: Hepatic resection with removal of tumor thrombi and HCC should increase the curative effects and be encouraged for the prolongation of life span and quality of life for HCC patients with PVTT, whereas the best therapeutic method for HCC with PVTT is with regional hepatic chemotherapy or chemoembolization after hepatic resection with removal of tumor thrombi. 展开更多
关键词 Chemoembolization Therapeutic Neoplasm Circulating Cells Adult Aged Antineoplastic Agents Carcinoma Hepatocellular Combined Modality Therapy Comparative Study Female Hepatic Artery Humans LIGATION Liver Neoplasms Male Middle Aged Portal Vein Prognosis Research support Non-U.S. Gov't Survival Rate
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赵楼矿深部软岩巷道变形破坏机理及控制技术 被引量:82
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作者 孟庆彬 韩立军 +2 位作者 乔卫国 林登阁 范加冬 《采矿与安全工程学报》 EI 北大核心 2013年第2期165-172,共8页
基于赵楼煤矿井底车场巷道围岩矿物成分分析、室内岩石力学试验、巷道地应力测试、围岩松动圈测试等巷道地质力学测试技术手段,深入揭示了深部巷道围岩变形破坏机理;针对赵楼煤矿深部巷道低围岩强度与高应力的支护难题,提出了以内注浆... 基于赵楼煤矿井底车场巷道围岩矿物成分分析、室内岩石力学试验、巷道地应力测试、围岩松动圈测试等巷道地质力学测试技术手段,深入揭示了深部巷道围岩变形破坏机理;针对赵楼煤矿深部巷道低围岩强度与高应力的支护难题,提出了以内注浆锚杆为核心的锚杆+锚索+锚注"三锚"联合支护体系;为反映深部巷道、硐室开挖后围岩的变形特征与支护结构受力情况,对巷道围岩收敛变形与锚杆受力情况进行了实时监测。监测结果表明,采用"三锚"联合支护体系能够有效地控制深部巷道围岩的大变形及底鼓,保持了巷道的长期稳定与安全。 展开更多
关键词 深部巷道 支护 围岩控制 监控量测
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Inhibiting effect of antisense oligonucleotides phosphorthioate on gene expression of TIMP-1 in rat liver fibrosis 被引量:73
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作者 Qing He Nie Yong Qian Cheng Yu Mei Xie Yong Xing Zhou Yi Zhan Cao The Center of Infectious Disease Diagnosis and Treatment of PLA,Tangdu Hospital,Forth Military Medical University,Xi’an 710038,Shaanxi Province,ChinaDr,Qing He Nie graduated from Qinghai Medical College as a doctor in 1983,got master degree at Beijing 302 Army Hospital in 1993,got doctor degree at the Third Military Medical University in 1998,engaged in postdoctoral research at the Fourth Military Medical University from 1998 to 2000,now an associate professor,specialized in clinical and experimental research of infectious diseases,had more than 90 papers published,coauthor of ten books,first author of one book. 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第3期363-369,共7页
AIM: To observe the inhibition of antisense oligonucleotides (asON) phosphorthioate to the tissue inhibitors metalloproteinase-1 (TIMP-1) gene and protein expression in the liver tissue of immunologically induced hepa... AIM: To observe the inhibition of antisense oligonucleotides (asON) phosphorthioate to the tissue inhibitors metalloproteinase-1 (TIMP-1) gene and protein expression in the liver tissue of immunologically induced hepatic fibrosis rats. The possibility of reversing hepatic fibrosis through gene therapy was observed. METHODS: Human serum albumin (HSA) was used to attack rats, as hepatic fibrosis model, in which asONs were used to block the gene and protein expressing TIMP-1. According to the analysis of modulator, structure protein, coding series of TIMP-1 genome, we designed four different asONs. These asONs were injected into the hepatic fibrosis models through coccygeal vein. The results was observed by RT-PCR for measuring TIMP-1 mRNA expression, immunohistochemistry and in situ hybridization for collagen I, II, special staining of collagen fiber, and electron microscopic examination. RESULTS: Hepatic fibrosis could last within 363 days in our modified model. The expressing level of TIMP-1 was high during hepatic fibrosis process. It has been proved by the immunohistochemical and the electron microscopic examination that the asON phosphorthioate of TIMP-1 could exactly express in vivo. The effect of colchicine was demonstrated to inhibit the expressing level of mRNA and the content of collagen I, III in the liver of experimental hepatic fibrosis rats. However, the electron microscopy research and the pathologic grading of hepatic fibrosis showed that there was no significant difference between the treatment group and the model group (P】 0.05). CONCLUSION: The experimental rat model of hepatic fibrosis is one of the preferable models to estimate the curative effect of anti-hepatic fibrosis drugs. The asON phosphorthioate of TIMP-1 could block the gene and protein expression of TIMP-1 in the liver of experimental hepatic fibrosis rats at the mRNA level. It is possible to reverse hepatic fibrosis, and it is expected to study a new drug of antihepatic fibrosis on the genetic level. Colchicine has very limited th 展开更多
关键词 Gene Therapy Animals Collagen Type I Collagen Type III Disease Models Animal Female Gene Expression Hepatocytes Immunohistochemistry Liver Liver Cirrhosis Microscopy Electron Oligonucleotides Antisense PROCOLLAGEN RNA Messenger RATS Rats Wistar Research support Non-U.S. Gov't Tissue Inhibitor of Metalloproteinase-1
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教育信息化2.0视域下的“互联网+教育”要素与功能研究 被引量:72
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作者 刘革平 余亮 +1 位作者 龚朝花 吴海燕 《电化教育研究》 CSSCI 北大核心 2018年第9期37-42,74,共7页
《国务院关于积极推进"互联网+"行动的指导意见》和教育部《教育信息化2.0行动计划》两个文件的颁布,引起了关于"互联网+教育"与教育信息化2.0之间关系的广泛讨论,各地的教育信息化实践也迫切需要学界提出有关理论... 《国务院关于积极推进"互联网+"行动的指导意见》和教育部《教育信息化2.0行动计划》两个文件的颁布,引起了关于"互联网+教育"与教育信息化2.0之间关系的广泛讨论,各地的教育信息化实践也迫切需要学界提出有关理论。文章以教育部课题为基础,主要研究了教育信息化2.0与"互联网+教育"的相互关系,论述了"互联网+教育"的核心要素与主要功能。文章提出了"互联网+教育"的五个核心要素:学习资源、学习方式、师生关系、教学环境和管理模式;从"互联网+"对教育的重构和对教育信息化2.0的支撑两个方面讨论了"互联网+教育"的功能。文章认为,"互联网+教育"从思想源泉、创新工具和变革途径三个方面对教育信息化2.0起重大支撑作用。 展开更多
关键词 “互联网+教育” 教育信息化2.0 核心要素 重构 支撑
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Growth inhibition and apoptosis induction Sulindac on Human gastric cancer cells 被引量:64
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作者 Yun-Lin Wu~1 Bo Sun~1 Xue-Jun Zhang~2 Sheng-Nian Wang~2 Heng-Yi He~2 Min-Min Qiao~1 Jie Zhong~1 Jia-Yu Xu~1 1 Department of Gastroenterology,Ruijin Hospital,Shanghai Second Medical University,Shanghai 200025,China2 Institude of Biochemistry and Cell Biology,Shanghai Institues for Biological Sciences,Chinese Academy of Sciences.Shanghai 200025,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第6期796-800,共5页
AIM: To evaluate the effects of sulindac in inducing growth inhibition and apoptosis of human gastric cancer cells in comparison with human hepatocellular carcinoma (HCC) cells. METHODS: The human gastric cancer cell ... AIM: To evaluate the effects of sulindac in inducing growth inhibition and apoptosis of human gastric cancer cells in comparison with human hepatocellular carcinoma (HCC) cells. METHODS: The human gastric cancer cell lines MKN45 and MKN28 and human hepatocellular carcinoma cell lines HepG(2) and SMMC7721 were used for the study. Anti-proliferative effect was measured by MTT assay, and apoptosis was determined by Hoechst-33258 staining, electronography and DNA fragmentation. The protein of cyclooxygenase-2 (COX-2) and Bcl-2 were detected by Western dot blotting. RESULTS: Sulindac could initiate growth inhibition and apoptosis of MKN45, MKN28, HepG(2) and SMMC7721 cells in a dose-and time-dependent manner. Growth inhibitory activity and apoptosis were more sensitive in HepG(2) cells than in SMMC7721 cells, MKN45 and MKN28 cells. After 24 hours incubation with sulindac at 2mmol x L(-1) and 4mmol x L(-1), the level of COX-2 and Bcl-2 protein were lowered in MKN45, SMMC7721 and HepG(2) cells but not in MKN28 cells. CONCLUSION: Sulindac could inhibit the growth of gastric cancer cells and HCC cells effectively in vitro by apoptosis induction, which was associated with regression of COX-2 and Bcl-2 expression. The growth inhibition and apoptosis of HCC cells were greater than that of human gastric cancer cells. The different effects of apoptosis in gastric cancer cells may be related to the differentiation of the cells. 展开更多
关键词 Anti-Inflammatory Agents Non-Steroidal Apoptosis Carcinoma Hepatocellular Cell Division Cells Cultured Comparative Study Humans Liver Neoplasms Research support Non-U.S. Gov't Stomach Neoplasms SULINDAC
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龙滩地下洞室群围岩稳定性分析 被引量:52
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作者 杨典森 陈卫忠 +3 位作者 杨为民 李术才 李廷春 朱维申 《岩土力学》 EI CAS CSCD 北大核心 2004年第3期391-395,共5页
大型地下洞室群的开挖和支护结构与围岩的稳定性密切相关,龙滩地下洞室群是布置在陡倾角层状结构岩体的巨型地下结构。应用FLAC3D方法,研究龙滩地下洞室群在开挖和支护过程中围岩的变形特征以及支护结构的受力特点,并将位移计算结果和... 大型地下洞室群的开挖和支护结构与围岩的稳定性密切相关,龙滩地下洞室群是布置在陡倾角层状结构岩体的巨型地下结构。应用FLAC3D方法,研究龙滩地下洞室群在开挖和支护过程中围岩的变形特征以及支护结构的受力特点,并将位移计算结果和现场监测结果进行比较,结果表明:数值计算的结果与监测结果规律基本一致,但数值计算位移的量值比监测结果略大。由此可知,采用本计算方法模拟急倾斜岩体内开挖大型地下洞室群具有较强的可靠性。 展开更多
关键词 FLAC 地下洞室 开挖 支护 稳定性
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超前管棚注浆支护技术在极复杂断层带中的应用 被引量:68
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作者 赵毅鑫 姜耀东 +2 位作者 孟磊 王涛 刘华博 《采矿与安全工程学报》 EI 北大核心 2013年第2期262-266,共5页
基于煤矿巷道采用超前管棚注浆支护技术顺利通过复杂断层带的实际案例,研究了巷道通过极复杂断层带面临的破碎围岩变形控制问题。通过计算确定了超前管棚注浆支护的设计参数,采用数值计算手段分析了过断层区域不同支护条件下的围岩应力... 基于煤矿巷道采用超前管棚注浆支护技术顺利通过复杂断层带的实际案例,研究了巷道通过极复杂断层带面临的破碎围岩变形控制问题。通过计算确定了超前管棚注浆支护的设计参数,采用数值计算手段分析了过断层区域不同支护条件下的围岩应力和巷道变形情况,并针对施工后的管棚支护巷道变形量进行了现场实测,总结了超前管棚注浆支护技术在巷道通过复杂断层带的成功经验。实践证明:超前管棚注浆支护技术提高了围岩的完整性及整体承载能力,能够形成较强的预支护体系,可应用于复杂断层带的破碎围岩变形控制,但需辅以物探手段提高注浆质量、加强监测才能保障巷道顺利通过复杂断层带,本文经验可对类似工程的设计和施工提供借鉴。 展开更多
关键词 管棚注浆 支护 巷道 断层带
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Association of H.pylori infection with gastric carcinoma:a Meta analysis 被引量:66
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作者 Fu-Bo Xue~1 Yong-Yong Xu~1 Yi Wan~1 Bo-Rong Pan~2 Jun Ren~2 Dai-Ming Fan~3 1 Department of Health Statistics,Department of2 Oncology3 Gastroenterology of XiJing Hospital,the Fourth Military Medical University,Xi’an 710032,Shaanxi Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第6期801-804,共4页
AIM: To follow the principles of evidence based medicine to reach the integrated results of these studies. METHODS: Twenty-one papers of case-control studies were selected, including 11 on gastric cancer,7 on precance... AIM: To follow the principles of evidence based medicine to reach the integrated results of these studies. METHODS: Twenty-one papers of case-control studies were selected, including 11 on gastric cancer,7 on precancerous lesion of stomach and 3 on lymphoma of stomach. Meta analysis was used to sum up the odds ratios (OR) of these studies. RESULTS: H. pylori vs gastric cancer (intestinal and diffuse type): the odds ratio from the fixed effect model is 3.0016 (95% CI: 2.4197-3.7234, P【0.001). H. pylori vs precancerous lesion of stomach: a random effect model was used to calculate the summary odds ratio and its value is 2.5635 (95% CI: 1.8477-3.5566, P【0.01). H. pylori vs lymphoma of stomach: though the quantity of literature is too small to make Meta analysis, the data of these 3 studies show that lymphoma of stomach is highly associated with H. pylori infections. CONCLUSION: Since it had been revealed that H. pylori infection pre-exists in gastric carcinoma and precancerous lesions, the results of Meta analysis present a strong evidence to support the conclusion that H. pylori infection is a risk factor for gastric carcinoma. 展开更多
关键词 Helicobacter pylori Case-Control Studies Helicobacter Infections Humans Research support Non-U.S. Gov't Stomach Neoplasms
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