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短串联重复位点ACTBP2(SE33)的扩增片段长度多态性研究 总被引:3,自引:0,他引:3
应用变性聚丙烯酸胺凝胶电泳(dn-PAGE)结合银染色技术对短串联重复(STR)位点ACTBP2(SE33)的扩增片段长度多态性(Amp-FLPs)进行了研究。在210名无关中国个体中观察到了25个等位基因,等位基因频率分布在0.007~0.093之间。基因型的分布符合Hardy-Weinberg定律,个体识别能力(DP)值为0.99,杂合度(H)为98.7%。七个家系分析的结果表明,该位点的遗传符合孟德尔遗传法则,未观察到变异。对几种常见的法医物证检材的分析表明,该分型系统对DNA降解放为严重的检村适用性强,而且灵敏度高(0.5ng),适合于法医学实际应用。 相似文献
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The importance of selenium (Se) deficiency in the pathogenesis of human diseases such as Keshan Disease has been extensively studied. It is possible that low Se-levels could cause immunosuppression and be an etiological factor in Sudden Infant Death (SID). We investigated 50 serum samples (40 SID and 10 non-SID victims) by atomic absorption spectrometry. The results show that there is no evidence of a serum selenium deficiency in SID-victims in the region of Aachen. A relationship between selenium concentration and the infant immune system still remains speculative and 21 samples even showed increased serum levels. It could be necessary to define a ‘local’ normal range by examining a greater number of healthy infants. 相似文献
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Ludwig Van Den Hauwe 《European Journal of Law and Economics》1998,5(3):267-279
Equity and efficiency are usually regarded as the main objectives of tax policy. Commenting on Dr. Reginald Hansen's doctoral dissertation, the author analyses the meaning of the equity-efficiency trade-off framework in the context of the ongoing debate regarding the reform of the German income-tax system. Schmoller's and Wagner's contrasting conceptions of income taxation are discussed. The role of the tax law as an instrument of interventionism within the framework of the social market economy, especially through the use of tax incentives, is highlighted. Contrary to Dr. Hansen, the author adopts an Austrian viewpoint and argues that both the (catallactic) efficiency and equity of tax incentives are disputable, especially but not uniquely through their (ab)use in tax shelter constructions. 相似文献
889.
多重PCR检测FFv三个基因座在景颇族人群中的遗传多态性 总被引:1,自引:0,他引:1
短串联重复序列(STR)是由几个碱基对作为核心单位串联重复形成的一类DNA序列,作者将3个STR基因座在同一反应体系中进行互不干扰的复合扩增,采用高分辨率的聚丙烯酰胺凝胶电泳分离、银染法显影技术,对云南省景颇族的F13A01,FESFPS和vWA等3个基因座等位基因的基因频率进行了调查,获得了满意的结果,显示了广阔的应用前景。F13A01基因座观察到8个等位基因、13个基因型;FESFPS基因应观察到7个等位基因、18个基因型;vWA基因应观察到7个等位基因、21个基因型。 相似文献
890.
Robert A. Johnson John P. Hoffmann S. Susan Su Dean R. Gerstein 《Journal of Quantitative Criminology》1997,13(4):429-467
Multilevel growth curve models provide a means of analyzing individual differences in the growth of deviance, allow a number of theories to be integrated in a single model, and can help to unify research on deviant/delinquent/criminal careers at different stages of the life cycle. Building on the distinction between population heterogeneity and state dependence as alternative explanations of persistent individual differences in deviance (Heckman, 1981; Nagin and Paternoster, 1991), we show that models with two levels can be used to represent and analyze a variety of criminological theories. The first level (level 1) uses repeated measurements on individuals to estimate individual-level growth curves. The second level treats the level 1 growth curve parameters (e.g., slope, intercept) as outcome variables and uses time-invariant factors to explain variation in these parameters across individuals. We illustrate this approach by estimating a model of growth in deviance drawn from Gottfredson and Hirschi's deviant propensity theory. An innovative feature is the assumption that adolescents' expected growth curves of deviance follow a classical Pearl-Verhulst logistic growth model (Pearl, 1930). The results suggest that five risk factors—parental psychiatric problems, lack of parental support, living arrangements with zero or one parent in residence, low family income, and male gender—have strongly positive effects on deviant propensity. For example, adolescents with no supportive parents, and no other risk factors, have expected asymptotic levels of deviance (peak levels attained at about age 18) that are about twice as high as those of adolescents with no risk factors. Yet more than two-thirds of the individual-level variability in growth curves is unexplained by the five risk factors. This unobserved heterogeneity would remain hidden in analyses using conventional structural equations models and the same explanatory variables. 相似文献