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The use of the LightCycler for the detection of Y chromosome SNPs   总被引:3,自引:0,他引:3  
A novel methodology based on PCR monitoring on-line with fluorescent formats using the LightCycler for Y chromosome SNP typing is proposed. The main advantages of the system are the time necessary for the analysis (which is around 20 min), the robustness and the accuracy of the method and especially its sensitivity, which permits the detection of the male component in male-female mixtures up to 1:300 for some of the SNPs.Singleplexes of four different SNPs (M9, sY81, SRY-1532 and SRY-2627) as well as two duplexes (M9 and sY81 on the one hand and SRY-1532 and SRY-2627 on the other) were efficiently implemented. A simultaneous amplification and analysis of the four SNPs is also possible. It seems difficult with the current methodology to implement more than a quadruplex.  相似文献   
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The societal transformation underway in Poland createda fundamental challenge to the occupational health and safety system, as the ideological and administrative principles on which it was founded vanished along with the communist-dominated regime. This paper examines the regulatory reform in Poland during the 1990s: its structural elements, implementation record and future prospects. Drawing on five case studies of privatized firms, a mailed questionnaire, and policy and institutional analysis, we find that Poland had considerable success in developing an effective regulatory system for managing occupational health hazards in privatized sector while also achieving considerable socioeconomic progress. The fundamental legitimacy of the regulators and regulatory process, the availability of information about firms and regulatory intents, and the capacity for case-specific decision making, are among the key explanatory factors. The case-specific implementation in Poland is consistent with models advocated by several authors in relation to other industrialized European economies (termed variously as negotiated compliance, tit-for-tat, cooperation-deterrence), despite a uniquely Polish context related to the continuing legacy of the communist era. The study also shows how in Poland a good fit between regulatory institutions and policies on the one hand, and their social context on the other hand, contributes to the effectiveness of the regulatory system.  相似文献   
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Calculation of age from fetal and newborn remains may be problematic, and when these remains are altered by maceration, decomposition or burning, age may be more difficult to discern. When soft tissue indicators are transformed, then two techniques exist for accurate age determination; dental development, which may prove difficult given the degree of tissue alteration; and appearance, size and fusion of ossification centers, including diaphyseal length, which may yield inaccurate ages if shrinkage is not accounted for. This study is undertaken to facilitate age calculation by systematically re-evaluating diaphyseal shrinkage and determine shrinkage rates from wet to carbonized states and wet to calcined states using Petersohn and K?hler's data, originally published in German and then published in Fazekas and Kósa (1978:362-369). Average shrinkage, standard deviation, minimum and maximum values are calculated for each diaphysis and then for all diaphyses between 4-10 lunar months (LM) and for newborns. Associated values for carbonized diaphyses are: 4 LM--32.50% +/- 12.12%; 5 LM--14.04% +/- 4.44%; 6 LM--6.78% +/- 1.06%; 7 LM--4.18% +/- 0.31%; 8 LM--3.47% +/- 0.42%; 9 LM--3.05% +/- 0.18%; 10 LM--2.46% +/- 0.67%; and in newborns 2.16% +/- 0.29%. Similar values for calcined diaphyses are: 4 LM--40.11% +/- 17.51%; 5 LM--18.29% +/- 4.42%; 6 LM--9.84% +/- 1.27%; 7 LM--9.82% +/- 0.51%; 8 LM--9.42% +/- 0.72%; 9 LM--9.45% +/- 0.33%; 10 LM--8.94% +/- 0.37%; and in newborns 8.96% +/- 0.49%. These findings suggest that percent shrinkage due to carbonization and calcination is greatest in the earliest age groups, decreasing substantially with advancing age. The rates of shrinkage, however, vary by the burning process utilized and age group studied. These general findings are similar to those of Petersohn and K?hler, yet specific values for percent shrinkage vary greatly from values cited in this analysis. These data provide a means to assess the degree of shrinkage that occurs for each diaphysis for each given age group.  相似文献   
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Research on the use of municipal corporations to deliver local and regional public services has evolved significantly in the past decade. Most of this work addresses the performance of this service-delivery mode in relation to local bureaucracies. However, much less is known about the drivers for the adoption of municipal corporations in the first place. This article reviews the main determinants of adoption – service characteristics, institutional and regulatory settings, political constraints and financial conditions – and highlights the need for comparative research across countries.  相似文献   
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