细胞外钙受体调节人脐静脉内皮细胞游离钙离子浓度的研究

为探讨人脐静脉内皮细胞(HUVEC)游离钙离子浓度是否受细胞外钙受体(CaR)的调节。采用Westernblot及RT-PCR技术检测CaR在HUVEC中蛋白及mRNA表达。使用CaR激动剂精胺,负性变构调节剂Calhex231,通过钙荧光探针(Fura-2/AM)负载HUVEC检测细胞内钙离子浓度([Ca2+]i)。结果显示:(1)HUVEC中有CaR的表达。(2)在Fura-2/AM负载HUVEC中加入精胺刺激,[Ca2+]i为△ratio=0.24±0.01,先加入Calhex231作用1min后再加入Calhex231+精胺刺激,[Ca2+]i为△ratio=0,两组比较差异有统计学意义(P0.05)。由此可知,CaR调节HUVEC游离钙离子浓度。     

Antimycin类天然产物抗三阴性乳腺癌细胞MDA-MB-231作用机制初步研究

研究Antimycin类天然产物对三阴性乳腺癌细胞MDA-MB-231特异性生长抑制和杀伤作用.三种结构类似的天然产物Antimycin-1,-2和-3对MDA-MB-231细胞生长都有很强的抑制作用,其IC50分别为1.34±0.07,160±20和180±50 nmol·L-1,Antimycin-1 活性是 An...     

基于PLC的温度检测与控制

介绍了利用可编程控制器组成温度检测与控制系统,此方案主要是利用热电偶传感器测温,利用TD400C进行温度设定、显示和报警.阐述TD400C的工作原理及其使用方法,论述了可编程控制器控制系统的设计方案及其控制原理和配置,重点阐述了可编程控制器系统对温度的采集、转换与显示.     

Path loss modelling and comparison based on the radio propagation measurement at 3.5GHz

Wideband IMT-Advanced mobile communication systems tend to operate in the high frequency bandsdue to a relatively large capacity available .Thus,Measurement and modelling methods of radio propaga-tion characteristics are proposed for the field test of Chinese 4th generation(4G)trial system.The mea-surement system is established for 3 .5GHz based on the sophisticated measurement instruments and thevirtual instrument technology.The characteristic parameters of radio propagation such as path loss(PL)expone...     

雌二醇、二羟异黄酮对乳腺癌MDA-MB-231细胞周期和增殖活性的影响

检测雌二醇、二羟异黄酮对乳腺癌MDA-MB-231（MM231）细胞周期和增殖活性的影响,从而为研究其功能提供线索。采用MTT法检测细胞增殖活性;流式细胞仪（FCM）检测细胞周期的变化。得到雌二醇作为雌激素类药物,一定浓度能够促使乳腺癌MM231细胞G2／M期阻滞,引发凋亡;而二羟异黄酮作为植物雌激素,一定浓度也能使MM231细胞G2／M期阻滞,并能抑制MM231细胞生长,促使其凋亡。说明二羟异黄酮和雌二醇作为竞争性抑制剂,都可以抑制乳腺癌MM231细胞的生长,为临床治疗乳腺癌奠定了一定理论基础。     

灯盏乙素对乳腺癌细胞中lncRNAs表达的影响

检测灯盏乙素对乳腺癌MDA-MB-231细胞中的长链非编码RNA(LncRNAs)的相对表达量的影响,进一步探索灯盏乙素对肿瘤的作用机制.采用实时荧光定量PCR的方法,检测对照组与不同剂量组的灯盏乙素处理后的乳腺肿瘤细胞中lncRNAs MALAT1、NEAT1和p53基因mRNA的相对表达量,并观察细胞存活率.结果发现,灯盏乙素在低剂量(1、10、25μmol/L)时促进细胞增殖,而在高剂量50μmol/L以上时抑制细胞增殖.灯盏乙素在低剂量时使得乳腺癌MDA-MB-231细胞中MALAT1,NEAT1和p53基因的表达水平下降,而在100μmol/L的高剂量时MALAT1,NEAT1和p53基因的表达水平上升.灯盏乙素影响乳腺癌MDA-MB-231细胞中LncRNAs MALAT1和NEAT1基因以及p53基因的表达,并且存在剂量反应关系,低剂量与高剂量呈现出相反的表达量变化.     

乳腺癌转移抑制因子（BRMS1）在人乳腺癌细胞系中的表达受体研究

通过PCR方法研究乳腺癌转移抑制因子（BRMS1）在人乳腺癌细胞系MDA MB-231和MCF-7中的表达.质粒（MDA231PEF,MCF-7PEF）通过克隆到大肠杆菌中进行转化.对人乳腺癌细胞系MDA MB-231和MCF-7进行RNA提取并进行反转录.将基因部分敲除的BRMS1（MDA231 BRMS1rib1,MCF7BRMS1rib1）通过大肠杆菌进行克隆,研究BRMS1在MDA MB-231和MCF-7中的表达.结果表明BRMS1在MDA MB-231和MCF-7中均有明显的表达,基因部分敲除后表达减弱.由此说明BRMS1在人乳腺癌细胞系MDA MB-231和MCF-7中存在表达受体.     

Bailey Willis (1857-1949): Geological Theorizing and Chinese Geology

Bailey Willis was the second major American geologist to undertake reconnaissance research in China--in the years 1903-04. Together with the stratigrapher Eliot Blackwelder, topographer Harvey Sargent, and guide Li Shan, he travelled first in Shandong Province, then from Peking to Xian, thence across the mountains into Sichuan, and then by river via the Yangzi Gorges to Shanghai. It was hoped that they would discover the primeval ancestor of trilobites in China, but the search proved unsuccessful. Willis's stratigraphic findings are described, as are his structural interpretations of what he observed in China. His work in China gave rise to some unfounded speculations about the possible causes of lateral Earth movements, due to rocks of different densities being adjacent to one another in the Earth's crust. These ideas were followed by several other 'theories of the Earth' during Willis's later career, some of which were also probably related to his experiences in China. He seemingly practised the formulation of 'multiple working hypotheses'. The paper also discusses the influence of Willis's survey and stratigraphic work on the subsequent development of Chinese geology, with particular attention given to the various meanings of the term 'Sinian System'. Mention is made of later work in China on Lower Cambrian stratigraphy.     

Id3启动子/荧光素酶基因载体的构建及其在WEHI-231细胞中的活性表达

用PCR法从WEHI-231细胞基因组DNA扩增小鼠Id3(mId3)基因5’端含启动子序列的不同长度的DNA片段(mId3-pf)亚克隆至荧光素酶(Luc)报道基因载体PGV-B2,构建由mId3基因启动子片段控制的Luc报道基因重组载体mId3-pf/PGV-B2.用电穿孔术将mId3-pf/PGV-B2导入培养的WEHI-231细胞,用抗小鼠IgM抗体刺激转染后的WEHI-231细胞,24 h后测定胞内Luc活性.结果表明,4种Luc报道基因重组载体转染细胞均表现较高的mId3启动子活性,与空载体转染细胞相比,启动子活性分别升高25~60倍.抗IgM抗体刺激细胞后,Id3启动子活性较未刺激细胞均呈明显增高趋势,增高幅度可达2倍左右.表明抗IgM抗体诱导WEHI-231细胞Id3的上调表达与Id3转录活性的升高有关.     

微小区场强预测

提出用分块处理的方法,对复杂的地形地物进行处理,并用C^ Builder建立了地形地物数据库。依据Cost231模型进行微小区场强预测,与成熟的网络规划软件“WinProp”的预测值比较,得到了满意的结果。