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During the genomics era, the use of thermostable DNA polymerases increased greatly. Many were identified and described—mainly of the genera Thermus, Thermococcus and Pyrococcus. Each polymerase has different features, resulting from origin and genetic modification. However, the rational choice of the adequate polymerase depends on the application itself. This review gives an overview of the most commonly used DNA polymerases used for PCR application: KOD, Pab (Isis?), Pfu, Pst (Deep Vent?), Pwo, Taq, Tbr, Tca, Tfi, Tfl, Tfu, Tgo, Tli (Vent?), Tma (UITma?), Tne, Tth and others.  相似文献   
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Wives and Warriors: Women and the Military in the United States and Canada. Laurie Weinstein and Christie C. White. eds. Westport, CT: Bergin and Garvey, 1997. 252 pp.  相似文献   
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The in vivo effects of dexamethasone administration on liver and extrahepatic tissue carnitine concentrations were assessed in 48-h-starved rats. In heart and kidney, but not in liver, dexamethasone significantly increased total carnitine concentration. Acute (2.5 h) treatment with 2-tetradecylglycidate (TDG), a specific inhibitor of carnitine palmitoyl transferase 1, not only increased total hepatic carnitine concentrations, but also permitted an effect of dexamethasone (a further increase in hepatic carnitine concentration). The results are discussed in terms of acute (substrate-mediated) and chronic (hormonal) control of carnitine turnover.  相似文献   
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Complex ecological pressures affect the social dynamics of many primate species, but it is unclear how they affect primate speciation. Molecular tools are often used to answer questions about the evolutionary histories and social systems of primates. Mitochondrial DNA (mtDNA), in particular, is frequently used to answer many of these questions, but because it is passed from mothers to offspring it reveals only the histories of females. In many species, including chimpanzees, females generally disperse from their natal groups while males are philopatric, and thus differences in dispersal patterns likely leave different signatures in the genome. We previously analyzed samples from 187 unrelated male and female chimpanzees in Nigeria and Cameroon using 21 autosomal microsatellites and mtDNA sequences. Here, we examine the contributions of males and females in shaping the genetic history of these chimpanzees by genotyping a subset of 56 males at 12 Y-chromosome microsatellites. We found that Y-chromosome population structure differed from the results of analysis of mtDNA haplotypes. The results also revealed that males in rainforest habitats (Guinean and Congolian rainforests) are more closely related to one another than those inhabiting the savanna-woodland mosaic ecotone in central Cameroon. In contrast, the pattern of female relatedness did not differ across habitats. We hypothesize that these differences in population structure and patterns of relatedness among males in different habitat types may be due to differences in the community dynamics of chimpanzees in the ecotone vs. rainforests, and that these factors contribute to making Cameroon an engine of diversification for chimpanzees. Broadly, these results demonstrate the importance of habitat variation in shaping social systems, population genetics, and primate speciation.  相似文献   
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