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331.
When analysing trace materials and degraded DNA the issue of human specificity is highly important. Especially when it comes down to the analysis of mitochondrial DNA which is extremely susceptible to contamination authenticity is the main question. Therefore in the presented study mitochondrial primers were tested on their human specificity. In all cases it was possible to amplify DNA of animals with human mt-primers. These unintentional amplifications could only be decreased by choosing austere PCR parameters. The study implies the importance of comprehensive evaluation of primers, chemicals and PCR parameters.  相似文献   
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以水牛原生殖细胞(PGCs)为核供体,成熟水牛卵母细胞为受体,采用电融合法和胞质内直接注核法对水牛PGCs的核移植进行了研究.从水牛胎儿的生殖嵴或生殖腺分离得到PGCs,在胎儿成纤维细胞饲养层上传代培养后,进行核移植.结果显示,当采用电融合法时,PGCs核移植的融合率、分裂率、囊胚率和总囊胚率均显著高于胎儿成纤维细胞(P<0.05);当采用直接注核法进行核移植时,PGCs的核移植囊胚率显著高于胎儿成纤维细胞(P<0.05),但分裂率差异不显著(P>0.05).结果表明,水牛PGCs细胞是理想的核移植供体细胞.  相似文献   
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The National Forensic Laboratory Information System (NFLIS) is a drug surveillance program of the US Drug Enforcement Administration that systematically collects data on drugs that are seized by law enforcement and submitted to and analyzed by the Nation's forensic laboratories (NFLIS-Drug). NFLIS-Drug data are increasingly used in predictive modeling and drug surveillance to examine drug availability patterns. Given the complexity of the data and data collection, there are some common methodological pitfalls that we highlight with the aim of helping researchers avoid these concerns. The analysis done for this Technical Note is based on a review of the scientific literature that includes 428 unique, refereed article citations in 182 distinct journals published between January 1, 2005, and April 30, 2021. Each article was analyzed according to how NFLIS-Drug data were mentioned and whether NFLIS-Drug data were included. A sample of 37 articles was studied in-depth, and data issues were summarized. Using examples from the literature, this Technical Note highlights eight broad concerns that have important implications for the proper applications, interpretations, and limitations of NFLIS-Drug data with suggestions for improving research methods and accurate reporting of forensic drug data. NFLIS-Drug data are timely and provide key information to inform drug use trends across the United States; however, our present analysis shows that NFLIS-Drug data are misunderstood and represented in the literature. In addition to highlighting these issues, DEA has created several resources to assist NFLIS data users and researchers, which are summarized in the discussion.  相似文献   
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Extreme forms of custody represent the boundary points of state power. The configuration of the most restrictive corners of prison systems, and what goes on within them, is highly instructive in exposing the objectives, limits, and implications of state coercion at its most severe. Based on data collected in England & Wales and Norway, this article has two main aims. The first is to explore the degree to which “deep-end” confinement differs between jurisdictions with different penal philosophies. The second is to understand how the most extreme form of confinement in each jurisdiction differs from the more typical carceral experiences within each system and its overall penal ethos. Empirically, then, the article seeks to shine light into the deepest dominions of both prison systems, illuminating the experiential texture of extreme forms of imprisonment. It concludes by asking what can be inferred about Nordic exceptionalism, and about deep-end confinement more generally, by analyzing these domains.  相似文献   
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The Inner Enemies of Democracy. By Tzvetan Todorov, trans. Andrew Brown (Malden, MA: Polity Press, 2014), pp.vi + 201. £20.00 (cloth).  相似文献   
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