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曲古抑菌素A对乳腺癌细胞株MDA-MB-231增殖的影响

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山东医药 2009年第43期49卷 22-23页

作者：聂建云刘馨黄云超昆明医学院第三附属医院昆明650118

目的探讨曲古抑菌素A(TSA)对乳腺癌细胞株增殖的影响。方法培养乳腺癌细胞株MDA-MB-231,用组不同浓度TSA分别作用于细胞,于24、48、72、96 h用MTT比色法观察细胞生长情况,流式细胞术检测S期细胞的比例和周期素(Cyclin)D1、A2表达。结果... 详细信息

目的探讨曲古抑菌素A(TSA)对乳腺癌细胞株增殖的影响。方法培养乳腺癌细胞株MDA-MB-231,用组不同浓度TSA分别作用于细胞,于24、48、72、96 h用MTT比色法观察细胞生长情况,流式细胞术检测S期细胞的比例和周期素(Cyclin)D1、A2表达。结果72h内和4μmol/L的浓度范围内,乳腺癌细胞生长受到抑制,并有一定的时效关系;TSA作用后周期素Cyclin A2表达下降,Cyclin D1表达上升(P均<0.05)。结论TSA能抑制乳腺癌细胞生长,周期素Cyclin D1、Cyclin A2参与了抑制剂对细胞增殖周期的调控。

关键词：乳腺癌曲古抑菌素A 细胞增殖

滨海城市空间结构气候复杂适应研究——基于CAS的厦门城市空间结构优化探讨

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城市发展研究 2018年第4期25卷 78-85+153页

作者：常玮郑开雄运迎霞天津大学建筑学院厦门大学建筑与土木工程学院中国城市规划设计研究院厦门分院

气候变化与城镇化深刻影响着我国滨海城市安全与可持续发展,"气候适应"已成为城市应对气候变化的战略共识。研究基于复杂适应系统理论(CAS),构建城市空间结构气候适应优化理论框架;分析"空间结构"与"气候变化"复杂适应性特征,探讨城市... 详细信息

气候变化与城镇化深刻影响着我国滨海城市安全与可持续发展,"气候适应"已成为城市应对气候变化的战略共识。研究基于复杂适应系统理论(CAS),构建城市空间结构气候适应优化理论框架;分析"空间结构"与"气候变化"复杂适应性特征,探讨城市空间与气候系统适应性主体的交互性、复杂性以及适应性过程机制,构建城市空间结构气候适应模型,并以厦门市为具体案例城市进行实证研究,以期为我国滨海城市应对气候变化问题、适应气候变化规划提供科学依据和技术支撑。

关键词：滨海城市空间结构气候变化复杂适应优化厦门

水土匹配、空间效应及区域农业经济增长——基于中国2003-2013的经验分析

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中国人口·资源与环境 2016年第7期26卷 153-158页

作者：许长新林剑婷宋敏河海大学商学院江苏南京211100 江苏沿海资源经济研究中心江苏南京211100

水资源和土地资源是非常重要的自然资源,是农业经济发展不可或缺的物质要素。水资源与土地资源的合理匹配能够促进区域的资源优势转化为经济增长,从而促进区域农业经济发展。我国是一个人口众多的农业大国,同时也存在水资源与土地资源... 详细信息

水资源和土地资源是非常重要的自然资源,是农业经济发展不可或缺的物质要素。水资源与土地资源的合理匹配能够促进区域的资源优势转化为经济增长,从而促进区域农业经济发展。我国是一个人口众多的农业大国,同时也存在水资源与土地资源短缺的问题。本文结合我国农业水土资源自然禀赋与实际利用情况,首先利用中国2003-2013年的分省数据,选取单位耕地面积的广义农业水资源量测度方法和当量系数描述了我国农业水土资源匹配的现实,发现我国农业水资源与土地资源在空间上匹配程度不高,农业生产受到水土资源约束较强,农业水土资源的形成区域与消耗区域在空间上不相匹配;然后,在邻接权重矩阵下采用Moran’s I指数验证我国区域农业经济增长的空间关联性,结果显示我国各省农业经济增长存在显著的空间关系,呈现出高度的集聚性和非均质性。为避免估计结果有偏,本文在此基础上采用空间计量建模及估计方法,加入农业生产人、财、物等控制变量,测度水土匹配度对区域农业经济增长的空间溢出效应。结果显示,水土匹配度对区域农业经济发展的区域内和区域间的溢出效应都显著为正,总体上水土匹配度对区域农业经济发展具有正向的溢出效应,即水土匹配度对本地区农业经济增长具有促进作用;同时,由于相邻区域的水土资源自然禀赋条件类似,而且农业生产中存在"示范效应"和"模仿效应",水土匹配度对相邻地区农业经济增长也具有一定的促进作用。因此,采取相关措施优化农业水土资源匹配关系,对促进我国区域农业经济增长,保障我国粮食安全非常重要。

关键词：水土匹配农业经济增长空间溢出效应空间回归偏微分方法

Progress and prospects of horizontal well fracturing technology for shale oil and gas reservoirs

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Petroleum Exploration and Development 2022年第1期49卷 191-199页

作者： LEI Qun XU yun CAI Bo GUAN Baoshan WANG xin BI Guoqiang LI Hui LI Shuai DING Bin FU Haifeng TONG Zheng LI Tao ZHANG Haoyu Research Institute of Petroleum Exploration&Development PetroChinaBeijing 100083China CNPC Key Laboratory of Oil&Gas Reservoir Stimulation Langfang 065007China

By systematically summarizing horizontal well fracturing technology abroad for shale oil and gas reservoirs since the “13th Five-Year Plan”, this article elaborates new horizontal well fracturing features in 3D development of stacked shale reservoirs, small well spacing and dense well pattern, horizontal well re-fracturing, fracturing parameters optimization and cost control. In light of requirements on horizontal well fracturing technology in China, we have summarized the technological progress in simulation of multi-fracture propagation, horizontal well frac-design, electric-drive fracturing equipment, soluble tools and low-cost downhole materials and factory-like operation. On this basis, combined with the demand analysis of horizontal well fracturing technology in the “14th Five-Year Plan” for unconventional shale oil and gas, we suggest strengthening the research and development in the following 7 aspects:(1) geology-engineering integration;(2) basic theory and design optimization of fracturing for shale oil and gas reservoirs;(3) development of high-power electric-drive fracturing equipment;(4) fracturing tool and supporting equipment for long horizontal section;(5) horizontal well flexible-sidetracking drilling technology for tapping remaining oil;(6) post-frac workover technology for long horizontal well;(7) intelligent fracturing technology.

关键词： shale oil and gas horizontal well fracturing fracturing equipment fracturing parameter three-dimensional development intelligent fracturing

Early Neoproterozoic multiple arc–back-arc system formation during subduction–accretion processes between the Yangtze and Cathaysia blocks:New constraints from the supra-subduction zone NE Jiangxi ophiolite(South China)

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Early Neoproterozoic multiple arc–back-arc system formation...

CIP2A过表达对胃黏膜上皮细胞增殖和凋亡的影响

中国科学院地质与地球物理研究所2015年度（第15届）学术年会

作者： xin-Shui Wang Jun Gao Reiner Klemd Tuo Jiang Qing-Guo Zhai Xu-chang Xiao xin-Quan Liang Key Laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of Sciences University of Chinese Academy of Sciences Institute of Geology Chinese Academy of Geological Sciences Guangzhou Institute of Geochemistry Chinese Academy of Sciences

The NE Jiangxi ophiolite in the eastern Jiangnan Orogen is a tectonic mélange that mainly consists of individual tectonic blocks comprising pyroxenite,gabbro,basalt,diorite,granite and chert in a matrix of serpentinite or tuffaceous greywacke.A combined geochemical and geochronological study of the NE Jiangxi ophiolite was undertaken to constrain the timing and tectonic setting of its *** basalts were geochemically subdivided into three groups with different Fe Ot and Ti O *** 1 basalts have the lowest Fe Ot(12.17–13.07 wt.%)and Ti O(1.48–1.62 wt.%) contents and the lowest Nb/Yb(0.80–0.88) and Th/Nb(0.02–0.03) ***,they have normal mid-ocean ridge basalt(N-MORB)-like trace element patterns,suggesting derivation from an N-MORB-type mantle source without subduction *** 2 Fe–Ti basalts have the highest Fe Ot(15.52–16.30 wt.%) and Ti O(3.06–3.23 wt.%) contents,Nb/Yb and Th/Nb ratios from 1.75 to 1.89 and from0.11 to 0.15,respectively,and trace element patterns similar to those of back-arc basin *** geochemical characteristics suggest that Group 2 basalts were derived from a slightly enriched MORB-type mantle source with a minor subduction *** contrast,Group 3 Fe–Ti basalts have moderate Fe Ot(12.98–13.40 wt.%) and Ti O(2.37–2.71 wt.%) contents,and Nb/Yb and Th/Nb ratios from 1.28 to 1.45 and from 0.27 to 0.30,*** basalts further display markedly negative Nb–Ta anomalies and show a geochemical affinity to island-arc basalts(IAB),indicating a slightly enriched MORB-type mantle source that was significantly influenced by subduction-derived fluids and/or *** zircon U–Pb dating on gabbros gave ages of 995 ± 22 Ma and 993 ± 12 Ma,which are interpreted as the formation age of the NE Jiangxi *** zirconεHf(t)(+8.8 to + 13.8) values for the gabbros and whole-rock εNd(t)(+5.5 to + 6.6) values for the basalts indicate that the NE Jiangxi ophiolite originated from an isotopically homo

关键词： Zircon geochronology Supra-subduction zone ophiolite NE Jiangxi ophiolite Back-arc basin rifting Assembly of the South China

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中国病理生理杂志 2016年第10期32卷 1881-1886页

作者：张海云常香荣陕西省康复医院消化内科陕西西安710065

目的:探究蛋白磷酸酶2A癌性抑制因子(CIP2A)过表达对胃黏膜上皮细胞GES-1增殖和凋亡的影响。方法:RT-q PCR检测正常胃黏膜组织和胃息肉组织中CIP2A和cyclin D1的表达。将胃黏膜上皮GES-1细胞分为空白对照组、空载体对照组和CIP2A过表达... 详细信息

目的:探究蛋白磷酸酶2A癌性抑制因子(CIP2A)过表达对胃黏膜上皮细胞GES-1增殖和凋亡的影响。方法:RT-q PCR检测正常胃黏膜组织和胃息肉组织中CIP2A和cyclin D1的表达。将胃黏膜上皮GES-1细胞分为空白对照组、空载体对照组和CIP2A过表达组,分组感染GES-1细胞后,分别用MTT法和Brd U试剂盒检测细胞增殖能力,流式细胞术检测细胞的凋亡情况,Western blot法和RT-q PCR检测凋亡蛋白的表达,ELISA检测细胞培养上清炎性因子的浓度。用E2F1 siRNA转染细胞,检测各组细胞中p-Rb、E2F1和cyclin D1的蛋白水平。结果:与正常胃黏膜组织相比,腺瘤性胃息肉组织中CIP2A和cyclin D1的mRNA表达水平均明显升高,而增生性胃息肉中CIP2A和cyclin D1的水平并无明显变化。GES-1细胞感染CIP2A过表达重组腺病毒之后,细胞的增殖能力和细胞活力提高,细胞凋亡率降低,炎性因子IL-1β和IL-10分泌增加,p-Rb、E2F1和cyclin D1蛋白水平升高,而E2F1沉默降低p-Rb、E2F1和cyclin D1的蛋白水平。结论:CIP2A通过激活Rb/E2F1促进GES-1细胞的增殖并抑制凋亡。

关键词：蛋白磷酸酶2A癌性抑制因子细胞增殖细胞凋亡

(-)-Epigallocatechin-3-gallate inhibits VEGF expression induced by IL-6 via Stat3 in gastric cancer

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World Journal of Gastroenterology 2011年第18期17卷 2315-2325页

作者： Bao-He Zhu Hua-yun Chen Wen-Hua Zhan Cheng-You Wang Shi-Rong Cai Zhao Wang chang-Hua Zhang Yu-Long He Department ofGastrointestinal and Pancreatic Surgery First Affiliated HospitalSun Yat-Sen University Gastric Cancer Center of Sun Yat-SenUniversity Guangzhou 510080 Guangdong Province China Department of General Surgery First Affiliated Hospital Shenzhen University Shenzhen518035 Guangdong Province China

AIM: To demonstrate that (-)-Epigallocatechin-3-gallate (EGCG) inhibits vascular endothelial growth factor (VEGF) expression and angiogenesis induced by interleukin-6 (IL-6) via suppressing signal transducer and activator of transcription 3 (Stat3) activity in gastric cancer. METHODS: Human gastric cancer (AGS) cells were treated with IL-6 (50 ng/mL) and EGCG at different concentrations. VEGF, total Stat3 and activated Stat3 protein levels in the cell lyses were examined by Western blotting, VEGF protein level in the conditionedmedium was measured by enzyme-linked immunosorbent assay, and the level of VEGF mRNA was evaluated by reverse transcription polymerase chain reaction (RTPCR). Stat3 nuclear translocation was determined by Western blotting with nuclear extract, and Stat3-DNA binding activity was examined with Chromatin immunoprecipitation (ChIP) assay. IL-6 induced endothelial cell proliferation was measured with 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazoliumbromide assay, in vitro angiogenesis was determined with endothelial cell tube formation assay in Matrigel, and IL-6-induced angiogenesis in vitro was measured with Matrigel plug assay. RESULTS: There was a basal expression and secretion of VEGF in AGS cells. After stimulation with IL-6, VEGF expression was apparently up-regulated and a 2.4-fold increase was observed. VEGF secretion in the conditioned medium was also increased by 2.8 folds. When treated with EGCG, VEGF expression and secretion were dose-dependently decreased. IL-6 also increased VEGF mRNA expression by 3.1 folds. EGCG treatment suppressed VEGF mRNA expression in a dose-dependent manner. EGCG dose-dependently inhibited Stat3 activation induced by IL-6, but did not change the total Stat3 expression. When treated with EGCG or AG490, VEGF expressions were reduced to the level or an even lower level in the tumor cells not stimulated with IL-6. However, PD98059 and LY294002 did not change VEGF expression induced by IL-6. EGCG inhibited

关键词： Epigallocatechin-3-gallate Vascular endothelial growth factor Signal transducer and activator of transcription 3 Angiogenesis Gastric cancer

圆棒Nd:glass热容激光器的热过程半解析分析

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红外与激光工程 2012年第3期41卷 601-606页

作者：白冰史彭李隆常锐辛宇西安建筑科技大学理学院陕西西安710055

建立了基于Nd:glass热容激光器的热传导模型,利用半解析热分析理论,对于给定的边界条件和初始条件,分别求解出泵浦阶段和冷却阶段时圆棒Nd:glass晶体的Poisson方程的解,得出圆棒Nd:glass晶体的温度场、形变场以及由端面热形变引起的热... 详细信息

建立了基于Nd:glass热容激光器的热传导模型,利用半解析热分析理论,对于给定的边界条件和初始条件,分别求解出泵浦阶段和冷却阶段时圆棒Nd:glass晶体的Poisson方程的解,得出圆棒Nd:glass晶体的温度场、形变场以及由端面热形变引起的热焦距、附加光程差的计算公式。研究结果表明:当泵浦总功率为2kW,4阶超高斯分布LD对Nd:glass晶体泵浦4s时,获得泵浦阶段圆棒Nd:glass晶体最高温升67.10℃,最大形变量为35.45μm,中心处附加光程差为5.677μm。冷却阶段圆棒Nd:glass晶体冷却800 s后中心最大热形变量为0.943μm。为优化热容激光器提供了理论依据。

关键词：激光物理圆棒Nd:glass 热形变场光程差热焦距

Fe原子吸附对单层WS_2结构和性质的影响

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物理化学学报 2017年第9期33卷 1765-1772页

作者：徐位云汪丽莉宓一鸣赵新新上海工程技术大学基础教学学院上海201620 上海工程技术大学材料工程学院上海201620

本文采用基于密度泛函理论(DFT)的第一性原理方法研究了Fe原子吸附对单层WS_2结构和性质的影响。研究结果表明:Fe原子吸附在W原子的顶位最稳定,相应的原子吸附能为1.84 eV。Fe与衬底间的相互作用削弱了紧邻W―S键,使其键长增大0.011 nm... 详细信息

本文采用基于密度泛函理论(DFT)的第一性原理方法研究了Fe原子吸附对单层WS_2结构和性质的影响。研究结果表明:Fe原子吸附在W原子的顶位最稳定,相应的原子吸附能为1.84 eV。Fe与衬底间的相互作用削弱了紧邻W―S键,使其键长增大0.011 nm。由于衬底原子的影响,Fe原子d轨道的电子重新分布,形成了2μB左右的局域原子磁矩。在低覆盖度下(0.125和0.25 ML),磁性作用以超交换作用为主,铁磁序不稳定。而在高覆盖度下(0.5和1.0 ML),Fe原子间距减小,磁性作用以RKKY作用为主,铁磁序稳定。电子结构的计算结果显示,在高覆盖度下,Fe/WS_2结构在费米能级处的电子自旋极化率等于100%。自旋向上与向下通道分别为间接带隙的半导体和金属。在1.0 ML覆盖度下,自旋向上的禁带宽度约为0.94 eV。这说明Fe原子吸附可以将直接带隙的WS_2半导体转变成半金属,形成一种潜在的自旋电子器件材料。

关键词：密度泛函理论 Fe/WS_2 过渡金属硫化物交换作用半金属