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“把革命带回来”:社会学新视野的拓展 被引量:102
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作者 应星 《社会》 CSSCI 北大核心 2016年第4期1-39,共39页
本文在韦伯和陈寅恪等人的启发下,提出了关于中国革命的社会学研究的问题意识、分析框架和基本方法,试图将"革命"这个社会学的经典母题重新带回到中国社会学界,以此拓展社会学研究的新视野。这种新的研究路数尝试围绕阶级路... 本文在韦伯和陈寅恪等人的启发下,提出了关于中国革命的社会学研究的问题意识、分析框架和基本方法,试图将"革命"这个社会学的经典母题重新带回到中国社会学界,以此拓展社会学研究的新视野。这种新的研究路数尝试围绕阶级路线、民主集中制和群众路线等重点,在借鉴实证史学资料收集法的基础上,运用"社会学的想象力"和事件社会学的方式来深入理解中国共产党在革命时期建立起来的独特的政治文化及其所产生的复杂而深远的历史效果。 展开更多
关键词 革命 政治文化 路线 事件社会学
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大跨越输电塔-线体系动力特性分析 被引量:47
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作者 梁枢果 朱继华 王力争 《地震工程与工程振动》 CSCD 北大核心 2003年第6期63-69,共7页
大跨越输电塔-线体系的动力特征评估是其抗风、抗震设计的重要环节。本文在有关文献的基础上,建立了大跨越输电塔-线体系耦联振动动力特性分析的多自由度体系计算方法,并对大跨越输电塔-线体系工程实例的动力特性进行了分析,讨论了塔-... 大跨越输电塔-线体系的动力特征评估是其抗风、抗震设计的重要环节。本文在有关文献的基础上,建立了大跨越输电塔-线体系耦联振动动力特性分析的多自由度体系计算方法,并对大跨越输电塔-线体系工程实例的动力特性进行了分析,讨论了塔-线耦联振动对塔,线各自动力特性的影响,得到了若干结论。 展开更多
关键词 输电塔 导线 耦联体系 动力特性
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Tumor blood vessels formation in osteosarcoma:vasculogenesis mimicry 被引量:45
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作者 蔡宣松 贾永伟 +1 位作者 梅炯 汤如勇 《Chinese Medical Journal》 SCIE CAS CSCD 2004年第1期94-98,共5页
BACKGROUND: Osteosarcoma is characterized by high neovascularization and a high propensity for metastasis through bloodstream. This study was to examine whether there is evidence for vasculogenic mimicry in osteosarco... BACKGROUND: Osteosarcoma is characterized by high neovascularization and a high propensity for metastasis through bloodstream. This study was to examine whether there is evidence for vasculogenic mimicry in osteosarcoma and to illustrate mechanism of tumor blood vessels formation in osteosarcoma. METHODS: Osteosarcoma cell lines (U-2OS) were tested for their ability to form tubular networks in three-dimensional culture containing type I collagen. The structures of the tubular networks were observed with phase contrast microscope and transmission electron microscope (TEM). Morphometric studies using hematoxylin and eosin (HE) stain and CD31 immunohistochemical stain to show tumor-lined channels in human osteosarcoma were also performed. RESULTS: Observation with light microscope and TEM showed that highly aggressive osteosarcoma cell lines (U-2OS) formed networks containing channels when grown in three-dimensional culture containing type I collagen, in the absence of endothelial cells or fibroblasts. Morphometric observation using HE stain and CD31 immunohistochemical stain showed that tumor cell-lined channels were also detected in vivo in osteosarcoma; by comparison, all vascular areas in the pedicle of osteochondroma or outside osteochondroma were endothelial-lined. CONCLUSION: These observations strongly suggest that aggressive osteosarcoma cells may generate vascular channels that facilitate tumor perfusion independent of tumor angiogenesis and have the ability of vasculogenic mimicry. 展开更多
关键词 Bone Neoplasms Cell line Tumor Collagen Humans IMMUNOHISTOCHEMISTRY Neovascularization Pathologic OSTEOSARCOMA Research Support Non-U.S. Gov't
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Effects of Yigan Decoction on proliferation and apoptosis of hepatic stellate cells 被引量:44
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作者 YaoXX TangYW 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第3期511-514,共4页
AIM:To investigate the effects of Chinese herb Yigan Decoction on proliferation and apoptosis of the hepatic stellate cells (HSC) in vitro. METHODS: The study in vitro was carried out in the culture of HSC lines. Vari... AIM:To investigate the effects of Chinese herb Yigan Decoction on proliferation and apoptosis of the hepatic stellate cells (HSC) in vitro. METHODS: The study in vitro was carried out in the culture of HSC lines. Various concentrations of Yigan Decoction were added and incubated. Cell proliferation was detected with MTT colorimetric assay. Cell apoptosis was detected by electron microscopy, flow cytometry and TUNEL. RESULTS: The proliferation of HSC was inhibited by Yigan Decoction, which depending on dose and time significantly. The HSC proliferation rates of groups at the end concentrations 144 and 72(g.L(-1)) were 21.62% and 40.54% respectively, significantly lower than that of normal control group(P【0.01). The HSC proliferation rates of groups at the end concentrations 36, 18 and 9(g.L(-1)) were 54.05%, 45.95% and 51.35% respectively, lower than that of control group (P【0.05). When the end concentration was 4.5 g.L(-1), the proliferation rate was 83.78%, which appeared no significant differences compared with control group. At the same concentrations of 18 g.L(-1), the inhibitory effects of Yigan Decoction at 24 h, 48 h and 72 h time point were observed, the effects were time-dependent, and reached a peak at 72 h. Meanwhile, it was showed that the inducing effects of Yigan Decoction on HSC apoptosis were dose-dependent and time-dependent. The apoptosis index(AI) was detected by TUNEL. After Yigan Decoction had been incubated for 48 h at the end concentration of 18 g.L(-1), the AI (14.5+/-3.1)% was significantly higher than that of control group (4.3+/-1.3)% (P【0.01). When visualized under transmission electron microscopy, some apoptotic stellate cells were found, i.e. dilated endoplasmic reticulum, irregular nuclei, chromatin condensation and heterochromatin ranked along inside of nuclear membrane. By flow cytometry detection, after HSC was treated with Yigan Decoction at different concentrations of 36, 18 and 9(g.L(-1)) for 48 h, AI (%) were 13.3+/-3.2, 10.7+/-2.7 and 10.1+/-2.5 respectively, which 展开更多
关键词 ANIMALS Apoptosis Cell Division Cell line Drugs Chinese Herbal HEPATOCYTES Liver Cirrhosis PHYTOTHERAPY Rats Research Support Non-U.S. Gov't
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中国的杂交水稻 被引量:43
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作者 袁隆平 《中国水稻科学》 CAS 1986年第1期18-18,8-17,共11页
中国是世界上第一个在生产上利用水稻杂种优势的国家。1984年杂交水稻的种植面积达820万公顷,占全国水稻总面积的四分之一。杂交水稻一般比普通水稻增产20%左右。利用水稻的杂种优势,从技术上看,有三个难题。第一,要培育出细胞质雄性不... 中国是世界上第一个在生产上利用水稻杂种优势的国家。1984年杂交水稻的种植面积达820万公顷,占全国水稻总面积的四分之一。杂交水稻一般比普通水稻增产20%左右。利用水稻的杂种优势,从技术上看,有三个难题。第一,要培育出细胞质雄性不育系及其保持系和恢复系;第二,要选出优势强的杂交组合;第三,要有能获得大量第一代杂交种子的制种技术。中国在1964年开始杂交水稻的研究,1973年实现三系配套,1974年获得强优势杂交组合,1975年建立较完整的制种技术,1976年开始在生产上大面积推广。目前,已有早、中、迟,籼、粳等多种类型,适合在不同地区种植的杂交组合二十多个。杂交水稻的优势主要表现在四个方面,即较好的农艺性状,较高的生理机能,较强的抗性和较广的话应性。杂交水稻的生产程序较复杂,特别是在繁殖和制种过程中容易串粉而引起混杂。为了保证杂交水稻种子的纯度和质量并做到有计划地供种,在中国建立了一套较完整的良种繁育体系,由各级种子公司分工负责。除育种工作外,不少高等院校和研究单位在进行遗传、生理生化和形态等方面的研究,并取得一定成绩,化学杀雄配制的杂交水稻也初步成功,并在生产上有一定的种植面积。中国在杂交水稻上取得成功的基本经验是:领导重视和支持;有一个强有力的专家小组负责具体研究工作;开展有关学科间的大协作;加速世代,南繁北育,一年选育三代;培训大量技术骨干负责制种和推广;建立高产样板田和召开现场会,以说服各级领导和农民群众;有一个健全的繁殖、制种和推广体制。目前,中国杂交水稻的研究正在向纵深发展。如培育多种细胞质源不育系,选育优质、高产、多抗组合以及超高产组合方面均有较大进展。 展开更多
关键词 种植面积 播种面积 中华人民共和国 杂交水稻 MS line 杂种组合 杂交组合
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大跨越输电塔-线体系数值分析模型的研究 被引量:42
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作者 梁峰 李黎 尹鹏 《振动与冲击》 EI CSCD 北大核心 2007年第2期61-65,共5页
对于高柔大跨越输电塔-线体系这样的大型结构体系,强风和地震引起的体系响应,尤其是动力响应将十分显著,常常成为其结构设计的控制性因素。建立大跨越输电塔-线体系的数值分析模型,以求取其动力特性是其抗风、抗震设计的重要环节。本文... 对于高柔大跨越输电塔-线体系这样的大型结构体系,强风和地震引起的体系响应,尤其是动力响应将十分显著,常常成为其结构设计的控制性因素。建立大跨越输电塔-线体系的数值分析模型,以求取其动力特性是其抗风、抗震设计的重要环节。本文在有关文献的基础上,建立了大跨越输电塔-线体系动力特性的数值分析模型,对某工程实例的动力特性进行了数值分析,与经典的理论分析结果进行了对比和讨论,得到了若干结论。同时介绍了输电线路振动的基本特点,采用多质点模型对塔线体系的耦联振动进行了研究,重点分析了多质点模型的几个模型参数对动力特性的影响。对工程实例的仿真分析表明,该模型能较准确地反映输电线路的塔线耦联振动效应,值得推广应用。 展开更多
关键词 输电塔 导线 模型 动力特性
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管道泄漏的压力测量诊断方法实验研究 被引量:24
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作者 江崇礼 孟庆操 董明 《大连理工大学学报》 CAS CSCD 北大核心 1998年第1期101-104,共4页
介绍了一种基于通过测量压力检测管道泄漏的方法.它不需测量其他物理量,且具有一定的抗干扰能力.实验证明这是一种可行的管道泄漏检测方法.
关键词 压力波 数字滤波器 快速相关 管道 泄漏
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抗溃疡病杨树种类的调查研究 被引量:32
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作者 杨俊秀 李武汉 +1 位作者 符毓秦 刘玉媛 《西北林学院学报》 CSCD 1990年第4期1-10,共10页
本文对133个杨树种及无性系进行了溃疡病自然发病情况调查,同时对其中部分品种和无性系进行了室内人工接种。结果表明:不同派,派内、派间杂交种,同一杂交组合的后代中感病程度均有明显差异。室内人工接种感病程度差异的变化趋势和野外... 本文对133个杨树种及无性系进行了溃疡病自然发病情况调查,同时对其中部分品种和无性系进行了室内人工接种。结果表明:不同派,派内、派间杂交种,同一杂交组合的后代中感病程度均有明显差异。室内人工接种感病程度差异的变化趋势和野外自然发病程度差异的变化趋势基本一致。以沙兰杨、毛白杨、Ⅰ—214杨、Ⅰ-69杨表现最为抗病;北京杨、陕林2号杨最为感病;其它属于中间级别。 展开更多
关键词 杨树 抗病性 溃疡病 杂交种
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Vegetation-Climate Relationship and Its Application in the Division of Vegetation Zone in China 被引量:37
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作者 方精云 宋永昌 +1 位作者 刘鸿雁 朴世龙 《Acta Botanica Sinica》 CSCD 2002年第9期1105-1122,共18页
Distribution of vegetation is closely coupled with climate; the climate controls distribution of vegetation and the vegetation type reflects regional climates. To reveal vegetation_climate relationships is the foundat... Distribution of vegetation is closely coupled with climate; the climate controls distribution of vegetation and the vegetation type reflects regional climates. To reveal vegetation_climate relationships is the foundation for understanding the vegetation distribution and theoretically serving vegetation regionalization. Vegetation regionalization is a theoretical integration of vegetation studies and provides a base for physiogeographical regionalization as well as agriculture and forestry regionalization. Based on a brief historical overview on studies of vegetation_climate relationships and vegetation regionalization conducted in China, we review the principles, bases and major schemes of previous vegetation regionalization and discuss on several contentious boundaries of vegetation zones in the present paper. We proposed that, under the circumstances that the primary vegetation has been destroyed in most parts of China, the division of vegetation zones/regions should be based on the distribution of primary and its secondary vegetation types and climatic indices that delimit distribution of the vegetation types. This not only reveals the closed relationship between vegetation and climate, but also is feasible practically. Although there still are divergence of views on the name and their boundaries of the several vegetation zones, it is commonly accepted that there are eight major vegetation regions in China, i.e. cold temperate needleleaf forest region, temperate needleleaf and broadleaf mixed forest region, warm temperate deciduous broadleaf forest region, subtropical evergreen broadleaf forest region, tropical monsoon forest and rain forest region, temperate steppe region, temperate desert region, and Qinghai_Xizang (Tibetan) Plateau high_cold vegetation region. Analyzing characteristics of vegetation and climate of major vegetation boundaries, we suggested that: 1) Qinling Mountain_Huaihe River line is an important arid/humid climatic, but not a thermal climatic boundary, and thus can not also be regarde 展开更多
关键词 China dynamic vegetation regionalization arid/humid climate northern limit of subtropical zone Qinling Mountain_Huaihe River line thermal climate vegetation_climate relationship vegetation regionalization vegetation zone
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Relationships of climate change and tree ring of Betula ermanii tree line forest in Changbai Mountain 被引量:34
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作者 YU Da-pao GU Hui-yan +2 位作者 WANG Jian-dong WANG Qing-li DAI Li-min 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第3期187-192,共6页
Based on the tree-ring growth characteristics of Erman's birch (Betula ermanii charm.) and the relationships between it and climatic )'actors at elevation of 1950m, the sensitivity of tree lines in Changbai Mount... Based on the tree-ring growth characteristics of Erman's birch (Betula ermanii charm.) and the relationships between it and climatic )'actors at elevation of 1950m, the sensitivity of tree lines in Changbai Mountain to climatic factors was assessed. The results indicated tree line forest in Changbai Mountain had an obvious sensitivity to climate factors. However, difference from other study sits is that the main climatic control factor on tree-ring growth was not current growth season temperatures, as might be expected, but previous winter and current March temperature. Although the precipitation in the region was quite abundant, the tree-ring growth was still significantly correlated with the precipitation during previous winter and current spring. Additionally, climatic factors which influenced the Erman's birch growth were not the yearly variables, but seasonal and monthly variables. Therefore, the reported increase in yearly mean temperature and total yearly precipitation since 1980s was not responded by sustained increase in ring widths in recent decades. 展开更多
关键词 Climatic change dendrochronology Erman's birch Tree line in Changbai Mountain
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Metastatic human hepatocellular carcinoma models in nude mice and cell line with metastatic potential 被引量:34
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作者 Zhao-You Tang Fan-Xian Sun Jian Tian Sheng-Long Ye Yin-Kun Liu Kang-Da Liu Qiong Xue Jie Chen Jing-Lin Xia Lun-Xiu Qin Hui-Chuan Sun Lu Wang Jian Zhou Yan Li Zeng-Chen Ma Xin-Da Zhou Zhi-Quan Wu Zhi-Ying Lin Bing-Hui Yang Liver Cancer Institute of Fudan University and Zhongshan Hospital,Shanghai 200032,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第5期597-601,共5页
Metastatic human HCC model is needed for the studies on mechanism and intervention of metastatic recurrence. By using orthotopic implantation of histologically intact tissues of 30 surgical specimens, a patient-like m... Metastatic human HCC model is needed for the studies on mechanism and intervention of metastatic recurrence. By using orthotopic implantation of histologically intact tissues of 30 surgical specimens, a patient-like metastatic model of human HCC in nude mice (LCI-D20) and a low metastatic model of human HCC in nude mice (LCI-D35) have been established. All mice with transplanted LCI-D20 tumors exhibited extremely high metastatic ability including spontaneous metastasis to liver, lungs, lymph nodes and peritoneal seeding. Remarkable difference was also found in expression of some of the invasiveness related genes and growth factors between the LCI-D20 and LCI-D35 tumors. PAI-1 increased gradually following tumor progression in LCI-D20 model, and correlated with tumor size and AFP level. Phasic expression of tissue intercellular adhesion molecule-1 in this model was also observed. Using corneal micropocket model, it was demonstrated that the vascular response induced by LCI-D20 tumor was stronger than that induced by LCI-D35 tumor. Similar report on metastatic human HCC model in nude mice and human HCC cell line with metastatic potential was rarely found in the literature. This LCI-D20 model has been widely used for the studies on intervention of metastasis, including anti-angiogenesis,antisense approach, metalloproteinase inhibitor, differentiation inducer, etc. It is concluded that the establishment of metastatic human HCC model in nude mice and human HCC cell line with metastatic potential will provide important models for the in vitro and in vitro study of HCC invasiveness, angiogenesis as well as intervention of HCC recurrence. 展开更多
关键词 Animals Carcinoma Hepatocellular Disease Models Animal Humans Liver Neoplasms Experimental MICE Mice Nude Research Support Non-U.S. Gov't Tumor Cells Cultured
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Correlation and Path Analysis for Growth Traits in F_1 Population of Pearl Oyster Pinctada martensii 被引量:34
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作者 邓岳文 杜晓东 +2 位作者 王庆恒 符韶 黄荣莲 《Marine Science Bulletin》 CAS 2008年第2期68-73,共6页
120 pearl oysters (Pinctada martensii) were randomly sampled from F1 population, and shell length, shell width, shell height, shell weight and total weight of each sample were measured. Correlation and path analysis... 120 pearl oysters (Pinctada martensii) were randomly sampled from F1 population, and shell length, shell width, shell height, shell weight and total weight of each sample were measured. Correlation and path analysis were conducted on the basis of measurement data. The results showed that shell length, shell width, shell height, shell weight and total weight were significantly correlated (P 〈 0.05). Total weight was significantly and positively correlated with shell weight (r = 0.8970), shell height (r = 0.6974), shell width (r = 0.6521) and shell length (r = 0.5486). Shell weight, shell height, shell width and shell length had positive and direct effects on total wet weight, with the values of 0.6356, 0.1872, 0.1814 and 0.0599, respectively. The results indicated that growth traits (shell length, shell width, shell height, shell weight and total wet weigh) of the F1 population could be improved by direct or indirect selection. 展开更多
关键词 Pinctada martensii selected line F1 growth traits CORRELATION path analysis
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Specific CEA-producing colorectal carcinoma cell killing with recombinant adenoviral vector containing cytosine deaminase gene 被引量:29
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作者 Li-Zong Shen Wen-Xi Wu Qiang Ding Yi-Bing Hua,Department of General Surgery,The First Affiliated Hospital of Nanjing Medical University,Nanjing,210029,Jiangsu Province,China De-Hua Xu Zhong-Cheng Zheng Xin-Yuan Liu,Shanghai Institute of Biochemistry and Cell Biology,The Chinese Academy of Sciences,Shanghai,200031,China Kun Yao,Department of Microbiology and Immunology,Nanjing Medical University,Nanjing,210029,Jiangsu Province,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2002年第2期270-275,共6页
AIM: To kill CEA positive colorectal carcinoma cells specifically using the E coli cytosine deaminase (CD) suicide gene, a new replication-deficient recombinant adenoviral vector was constructed in which CD gene was c... AIM: To kill CEA positive colorectal carcinoma cells specifically using the E coli cytosine deaminase (CD) suicide gene, a new replication-deficient recombinant adenoviral vector was constructed in which CD gene was controlled under CEA promoter and its in vitro cytotoxic effects were evaluated. METHODS: Shuttle plasmid containing CD gene and regulatory sequence of the CEA gene was constructed and recombined with the right arm of adenovirus genome DNA in 293 cell strain. Dot blotting and PCR were used to identify positive plaques. The purification of adenovirus was performed with ultra-concentration in CsCl step gradients and the titration was measured with plaque formation assay. Cytotoxic effects were assayed with MTT method, The fifty percent inhibition concentration (IC(50)) of 5-FC was calculated using a curve-fitting parameter. The human colorectal carcinoma cell line, which was CEA-producing, and the CEA-nonproducing Hela cell line were applied in cytological tests. An established recombinant adenovirus vector AdCMVCD, in which the CD gene was controlled under CMV promoter, was used as virus control. Quantitative results were expressed as the mean +/- SD of the mean. Statistical analysis was performed using ANOVA test. RESULTS: The desired recombinant adenovirus vector was named AdCEACD. The results of dot blotting and PCR showed that the recombinant adenovirus contained CEA promoter and CD gene. Virus titer was about 5.0 X 10(14)pfu/L(-1) after purification. The CEA-producing Lovo cells were sensitive to 5-FC and had the same cytotoxic effect after infection with AdCEACD and AdCMVCD (The IC(50) values of 5-FC in parent Lovo cells, Lovo cells infected with 100 M.O.I AdCEACD and Lovo cells infected with 10 M.O.I AdCMVCD were 】15000, 216.5+/-38.1 and 128.8+/-25.4 micromol.L(-1), P【0.001, respectively), and the cytotoxicity of 5-FC increased accordingly when the m.o.i of adenoviruses were enhanced (The value of IC(50) of 5-FC was reduced to 27.9+/-4.2 micromol.L(-1) in 1000 M.O.I AdCEACD infected Lovo c 展开更多
关键词 Gene Therapy Genetic Vectors ADENOVIRIDAE Animals ANTIMETABOLITES Bystander Effect Carcinoembryonic Antigen Cell line Colorectal Neoplasms Cytosine Deaminase FLUCYTOSINE Hela Cells Humans Nucleoside Deaminases Promoter Regions (Genetics) Research Support Non-U.S. Gov't Tumor Cells Cultured
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直流GIL中自由线形金属微粒的运动与放电特性 被引量:31
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作者 王健 李庆民 +2 位作者 李伯涛 刘思华 王志远 《中国电机工程学报》 EI CSCD 北大核心 2016年第17期4793-4800,共8页
针对直流GIL中较常见且具有严重影响的自由线形金属微粒,搭建了贴合实际工况的封闭式同轴圆柱电极平台,同时使用高速相机和局放监测手段观测线形金属微粒的运动、局放与击穿行为。定量获得了微粒长度对站立与跳跃两种不同运动模式发生... 针对直流GIL中较常见且具有严重影响的自由线形金属微粒,搭建了贴合实际工况的封闭式同轴圆柱电极平台,同时使用高速相机和局放监测手段观测线形金属微粒的运动、局放与击穿行为。定量获得了微粒长度对站立与跳跃两种不同运动模式发生概率的影响;拍摄了站立线形微粒引起的电晕图像,同时监测、提取并统计微粒引起的局部放电情况;记录金属微粒引起的击穿图像,并基于流注理论分析了自由线形金属微粒引起的气隙击穿特性。研究表明:线形微粒的起动场强与微粒的长度基本无关,而与微粒的半径开方成正比,微粒越短,起动后越易达到跳跃运动状态,而微粒越长,越易保持站立状态;微粒引起的局部放电随着微粒长度的增大而更加剧烈;对于跳跃的自由线形微粒,其引起的微放电击穿间距随着微粒长度的增加而增加,击穿电压随着微粒长度的增加而降低。 展开更多
关键词 直流气体绝缘金属封闭输电线路(gas insulated metal enclosed transmission line GIL) 自由线形金属微粒 运动模式 局部放电特征 微放电间距
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A NONMONOTONE CONJUGATE GRADIENT ALGORITHM FOR UNCONSTRAINED OPTIMIZATION 被引量:28
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《Journal of Systems Science & Complexity》 SCIE EI CSCD 2002年第2期139-145,共7页
Abstract. Conjugate gradient methods are very important methods for unconstrainedoptimization, especially for large scale problems. In this paper, we propose a new conjugategradient method, in which the technique of n... Abstract. Conjugate gradient methods are very important methods for unconstrainedoptimization, especially for large scale problems. In this paper, we propose a new conjugategradient method, in which the technique of nonmonotone line search is used. Under mildassumptions, we prove the global convergence of the method. Some numerical results arealso presented. 展开更多
关键词 Unconstrained optimization conjugate gradient nonmonotone line search global convergence.
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Establishment and characterization of four human hepatocellular carcinoma cell lines containing hepatitis B virus DNA 被引量:28
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作者 Jae Ho Lee 1, Ja Lok Ku 1, Young Jin Park 1,2 , Kuhn Uk Lee 2, Woo Ho Kim 3 and Jae Gahb Park 1,2 《World Journal of Gastroenterology》 SCIE CAS CSCD 1999年第4期17-23,共7页
AIM To investigate the characteristics of newly established four hepatocellular carcinoma cell lines (SNU 739, SNU 761, SNU 878 and SNU 886) from Korean hepatocellular cancer patients. METHODS Morphologic and g... AIM To investigate the characteristics of newly established four hepatocellular carcinoma cell lines (SNU 739, SNU 761, SNU 878 and SNU 886) from Korean hepatocellular cancer patients. METHODS Morphologic and genetic studies were done. RESULTS All four lines grew as a monolayer with an adherent pattern, and their doubling times ranged from 20 to 29 hours. The viability rate was relatively high (88%-94%). Neither mycoplasmal nor bacterial contamination was present. The lines showed different patterns in fingerprinting analysis. The hepatitis B virus (HBV) DNA was integrated in the genomes of all four lines, and in all of them HBx, HBc and HBs transcripts were detected by reverse transcriptase PCR methods. Among the three cell lines used as control (Hep 3B, SK Hep1 and Hep G2), only Hep 3B showed HBx expression, and this line was used as a HBV integrated control. The RNA of albumin was detected in three lines (SNU 761, SNU 878 and SNU 886), that of transferrin in two lines (SNU 878, SNU 886), and that of IGF Ⅱ was detected in none of the cell lines. CONCLUSION These well characterized cell lines may be very useful for studying the biology of hepatocellular carcinoma in association with the hepatitis B virus. 展开更多
关键词 carcinoma HEPATOCELLULAR liver neoplasms HEPATITIS B VIRUS HEPATITIS x ANTIGEN CELL line
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Mapping of qGL7-2, a grain length QTL on chromosome 7 of rice 被引量:29
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作者 Gaoneng Shao Shaoqing Tang Ju Luo Guiai Jiao Xiangjin Wei Ao Tang Jianli Wu Jieyun Zhuang Peisong Hu 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2010年第8期523-531,共9页
A residual heterozygous line (RHL) carrying a heterozygous segment between two S SR loci RM 11 and RM134 on the rice chromo- some 7 was selected from a set of recombinant inbred lines from the cross D50 (javanica)... A residual heterozygous line (RHL) carrying a heterozygous segment between two S SR loci RM 11 and RM134 on the rice chromo- some 7 was selected from a set of recombinant inbred lines from the cross D50 (javanica)/HB277 (indica). The former parent produces much longer grains than the latter. Selfed progenies of this selection were analyzed genotypically (SSRs) and phenotypically (grain length). Grain length was discontinuously variable in the mapping populations, allowing for the placement of this QTL qGL7-2 within a -4.8 cM interval defined by RM351 and RM234. A set of new markers within this region were developed, which narrowed the QTL to a 278 kb region defined by the markers Indell and RM21945. This region contains 49 predicted genes. The results also suggest that the novel allele for grain length will be used for the application of marker assisted selection for the improvement of grain length. 展开更多
关键词 grain length MAPPING quantitative trait locus residual heterozygous line RICE
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2020年中国内地城轨交通线路概况 被引量:30
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作者 侯秀芳 梅建萍 左超 《都市快轨交通》 北大核心 2021年第1期12-17,共6页
截至2020年末,中国内地共45座城市开通城轨交通运营线路7 978.19 km,2020年当年新增运营线路长度1 241.99 km;"十三五"5年间,中国内地城轨交通新增运营线路长度总计达4 360 km,年均新开运营线路872 km。2020年,8座城市的新一... 截至2020年末,中国内地共45座城市开通城轨交通运营线路7 978.19 km,2020年当年新增运营线路长度1 241.99 km;"十三五"5年间,中国内地城轨交通新增运营线路长度总计达4 360 km,年均新开运营线路872 km。2020年,8座城市的新一轮建设规划(或规划方案调整)获批公示,获批项目涉及新增城轨交通线路长度共587.95 km,新增投资额共4 709.86亿元;"十三五"5年间,由国家发展改革委批复已获公示的新一轮城轨交通建设规划或建设规划调整方案中涉及新增规划线路长度总计4 001.74 km,新增计划投资额总计29 781.91亿元。 展开更多
关键词 城轨交通 线路 概况 运营 规划
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城区机载LiDAR数据与航空影像的自动配准 被引量:29
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作者 张永军 熊小东 沈翔 《遥感学报》 EI CSCD 北大核心 2012年第3期579-595,共17页
为解决机载LiDAR数据与航空影像集成应用中二者的配准问题,提出了一种机载LiDAR数据与航空影像配准的方法。首先,直接在LiDAR点云中提取建筑物3维轮廓线,通过将轮廓线规则化得到由两条相互垂直的直线段组成的建筑物角特征,并在航空影像... 为解决机载LiDAR数据与航空影像集成应用中二者的配准问题,提出了一种机载LiDAR数据与航空影像配准的方法。首先,直接在LiDAR点云中提取建筑物3维轮廓线,通过将轮廓线规则化得到由两条相互垂直的直线段组成的建筑物角特征,并在航空影像上提取直线特征;然后,根据影像初始外方位元素将建筑物角特征投影到航空影像上,并采用一定的相似性测度在影像上寻找同名的影像角特征;最后,将角特征的角点当作控制点,利用传统的摄影测量光束法区域网平差解求影像新的外方位元素。解算过程中采用循环迭代策略。本方法的主要特点是,直接从LiDAR点云中提取线特征,避免了常规方法从距离图(或强度图)中提取线特征所产生的内插误差。通过与现有基于点云强度图的配准方法的对比实验表明,在低精度初始外方位元素的辅助下,本文方法能够达到较高的配准精度。 展开更多
关键词 机载LIDAR 航空影像 配准 线特征 角特征
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试论运输通道的概念 被引量:10
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作者 黄承锋 宾雪峰 《重庆交通学院学报(社会科学版)》 2001年第4期49-52,共4页
以系统和发展的观念 ,将运输通道的组成概括为地带、线路系统、载体系统及管理系统 ,进而提出了整合性的运输通道概念。
关键词 地带 线路 载体 管理系统
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