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181.
将牛IgG2 Fc受体(boFcγ2R)编码区cDNA亚克隆到真核表达载体pcDNA3的巨细胞病毒启动子下游,构建了重组表达质粒pc3bo2R;以重组质粒转染COS-7细胞,用玫瑰花环试验检测boFcγ2R在转染细胞表面的表达,通过G418抗性筛选和连续克隆化,在转染细胞表面稳定表达了boFcγ2R受体分子,转染细胞的玫瑰花环形成率达90%。最后获得稳定表达boFcγ2R受体分子的COS-7转染细胞系,为受体的功能研究提供了良好的技术平台。  相似文献   
182.
Triton X-100快速提取甲醛固定、石蜡包埋组织内DNA的方法   总被引:8,自引:0,他引:8  
目的建立一种快速提取甲醛固定、石蜡包埋组织内DNA的方法。方法利用TritonX-100一步提取甲醛固定、石蜡包埋组织内DNA,并具体研究了不同浓度TritonX-100对提取后DNA-STR分型效果的影响。结果成功地一步提取出甲醛固定、石蜡包埋组织内DNA,浓度为1%的TritonX-100提取效果较好。结论利用TritonX-100提取甲醛固定、石蜡包埋组织内的DNA,为快速提取DNA提供了有效的途径,是法科学领域中一种值得推荐的方法。  相似文献   
183.
将构建的牛pMD 18-T-MSTN克隆载体与真核表达载体pef-dhfr1a酶切,回收牛MSTN目的片段及pef-dhfr1a载体,构建了牛MSTN基因的真核表达质粒pef-dhfr1a-MSTN,然后转染COS-7细胞,将牛MSTN成熟蛋白编码序列在COS-7细胞中进行了表达。提取转染细胞的总RNA,采用RT-PCR和Western-blotting方法,分别从mRNA水平和蛋白质水平上检测到了牛MSTN基因在COS-7细胞中的表达产物,证明已经成功构建出该基因的真核表达载体。  相似文献   
184.
Presumptive tests for blood play a critical role in the examination of physical evidence and in the determination of subsequent analysis. The catalytic power of hemoglobin allows colorimetric reactions employing phenolphthalein (Kastle‐Meyer test) to indicate “whether” blood is present. Consequently, DNA profiles extracted from phenolphthalein‐positive stains are presumed to be from blood on the evidentiary item and can lead to the identification of “whose” blood is present. Crushed nodules from a variety of legumes yielded phenolphthalein false‐positive reactions that were indistinguishable from true bloodstains both in color quality and in developmental time frame. Clothing and other materials stained by nodules also yielded phenolphthalein false‐positive reactivity for several years after nodule exposure. Nodules from leguminous plants contain a protein (leghemoglobin) which is structurally and functionally similar to hemoglobin. Testing of purified leghemoglobin confirmed this protein as a source of phenolphthalein reactivity. A scenario is presented showing how the presence of leghemoglobin from nodule staining can mislead investigators.  相似文献   
185.
The Grand Chamber has ruled that the data retention directive was invalid ex tunc since it seriously interfered with the fundamental rights to respect for private life and protection of personal data and exceeded the limits of the principle of proportionality which are provided for in the Charter. The scope and temporal effects of this ruling should be clarified, especially its legal impacts on national laws of Member States which enacted the directive. In addition, the findings of the Grand Chamber on geographical safeguards have far-reaching implications on the retention and storage of personal data in the EU.  相似文献   
186.
《欧盟研究、技术开发及示范活动第七框架计划》是迄今欧盟投资最多、内容最丰富、市场目的最明确的全欧洲性中长期重大科研与技术开发计划。该计划所资助的项目几乎都是针对国际科技发展最前沿的课题或者是具有基础性、前瞻性、预竞争性的科技难点。在计划实施过程中,欧盟在项目遴选程序,研发资金的筹集、拨付,风险共担融资工具(RSFF)的引入,财务报告审计以及科技项目最终成果的双重评估机制等诸多方面进行了创新,取得了非常显著的效果。欧盟在框架计划执行中取得的经验及制度成果对于我国创新型国家建设中的制度建设,无疑具有重要的参考借鉴价值。  相似文献   
187.
为了建立新城疫病毒(NDV)Mukteswar毒株的反向遗传操作系统,根据已测定的NDV Muk-teswar毒株的全基因组序列设计了5对引物,扩增出包含全基因组cDNA的5条片段,并按一定顺序依次克隆入pSL1180载体中,然后在cDNA 5′末端插入T7启动子序列,3′末端导入具有自我剪切功能的丁肝病毒核酶序列和T7转录终止信号,构建了能转录具有精确5′和3′末端全基因组cDNA的转录载体pNDVT7。将表达核蛋白、磷酸蛋白及转录大蛋白的辅助表达载体pCIneoNP、pCIneoP和pCIneoL与pNDVT7按一定比例混合共转染BRS-T7细胞,4 d后将细胞悬液接种9日龄SPF鸡胚,结果获得了高效价的重组病毒。表明本研究建立的反向遗传系统能高效、快速拯救重组新城疫病毒毒株。  相似文献   
188.
Abstract: Analysis of length polymorphism at short tandem repeat (STR) loci utilizing multiplex polymerase chain reaction (PCR) remains the primary method for genotyping forensic samples. The AmpF?STR® Identifiler® Plus PCR Amplification Kit is an improved version of the AmpF?STR® Identifiler® PCR Amplification Kit and amplifies the core CODIS loci: D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D21S11, CSF1PO, FGA, TH01, TPOX, and vWA. Additional loci amplified in the multiplex reaction are the sex‐determinant, amelogenin, and two internationally accepted loci, D2S1338 and D19S433. While the primer sequences and dye configurations were unchanged, the AmpF?STR® Identifiler® Plus PCR Amplification Kit features an enhanced buffer formulation and an optimized PCR cycling protocol that increases sensitivity, provides better tolerance to PCR inhibitors, and improves performance on mixture samples. The AmpF?STR® Identifiler® Plus PCR Amplification Kit has been validated according to the FBI/National Standards and Scientific Working Group on DNA Analysis Methods (SWGDAM) guidelines. The validation results support the use of the AmpF?STR® Identifiler® Plus PCR Amplification Kit for human identity and parentage testing.  相似文献   
189.
Due to the longstanding human presence in the region and the influence of social traditions, the genetic make-up of populations currently inhabiting Turkey (Anatolia) is quite complex. To characterize the patterns of genetic diversity in rural Central Anatolian villages, we analyzed samples collected at four local settlements for variation at 17 Y-chromosome STR and 15 autosomal STR loci. The resulting data reveal considerable diversity within these settlements, as well as some structure in the paternal genetic variation, with a limited number of haplotypes being shared between the communities. These findings have important implications for forensic studies of Turkish populations.  相似文献   
190.
Abstract: DNA amplification is a fundamental yet costly process used in DNA analysis. This study evaluated half‐reaction amplification (12.5, 12, and 13 uL) using the Promega Powerplex® 16 Kit with the hope of reducing sample analysis costs by half. A sensitivity study was completed, along with the testing of various blood stain samples including those with low (<0.40 ng) and high DNA concentrations (>3.0 ng), peak height imbalances, and allelic drop‐out. Also, 467 samples submitted to the MUFSC laboratory for testing were analyzed. Results indicate that half‐reaction amplification produced higher quality profiles than full‐reactions. Average peak heights increased by 85%, peak height imbalances improved, and drop‐out was eliminated in 75.8% of samples. Only eight of 467 case samples required re‐amplification, a success rate of 94% was observed, and the repeat rate decreased significantly. Finally, a DNA input of 0.25–1.0 ng is ideal for half‐reaction amplification.  相似文献   
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