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151.
测定了痢疾杆菌福氏 2a 30 1株与喹喏酮类药物耐药性相关的 gyrA基因和 parC基因的序列 ,并对其环丙沙星耐药诱变株的 gyrA和 parC基因喹喏酮类药物耐药性决定区 (QRDR)序列进行了测定分析。结果表明 ,痢疾杆菌福氏 2a 30 1株 gyrA和 parC基因分别为 2 6 2 5bp和2 2 5 6bp ,环丙沙星诱导的耐药菌 gyrA基因QRDR(2 4 5bp)发生氨基酸残基 6 9 Ala→Val和 87 Tyr→Asp改变 ,parC基因QRDR(2 37b)发生氨基酸残基 79 Ala→Asp、84 Ala→Glu和 85 Pro→Ala改变。这一研究结果对认识痢疾杆菌喹喏酮类药物耐药性的分子机理具有重要意义  相似文献   
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In this study, a new method was developed for the impurity profiling of illicit MDMA tablets. The extraction efficiency, linearity, repeatability and reproducibility of the method were evaluated. Eighty two MDMA tablets coming from presumed unrelated large seizures in 2004 (n >500 tablets) were analyzed by gas chromatography mass spectrometry (GC-MS) in order to assess the discrimination power of the method. The latter was found to be practical, robust, relatively easy to perform, highly discriminative and yielding good chromatography. In addition, some new impurities were detected and identified. Their chemical structures and mass spectra are reported.  相似文献   
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In a case of suicidal application of electricity differences between the rectal temperature of the body and the suspected time of death were observed.In order to answer the question whether an electric current from hand to hand over >30 min led to a rise in body temperature FEM-based computer simulations and animal experiments were carried out. Both resulted in a warming of the soft parts in the arm without warming the body core. Thus a temperature-based estimation of the time since death can also be used in cases with electricity as the cause of death. Besides, in the animal experiment we found a spontaneous rise in the body core temperature even without application of electricity which may be a reason for the typical temperature plateau after death.  相似文献   
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More than a decade after NAFTA (North American Free Trade Agreement) entered into force, the environmental effects of agricultural trade liberalization in Mexico are still controversial, emerging, and not fully understood. This paper contributes to the literature that aims to explore trends in input use in the agricultural sector in Mexico during the post-NAFTA period among both commercial/industrial and traditional/rainfed farmers, and examines the influence of the national and multilateral institutional framework on these outcomes. We decompose the post-NAFTA agricultural production data into scale, technique and composition effects to estimate the impact that trade liberalization has had on the use of fertilizer and land use, two key agricultural inputs for which reliable aggregate data is available. We conclude that among commercial farmers patterns of crop type specialization and significant technological improvements have led to some declines in fertilizer use but they have been offset by growth in fertilizer use associated with growing agricultural output. Among traditional farmers increased output and specialization in land-intensive grain crops are contributing to an increase in land under cultivation and technological improvements show the potential, but not yet not the strength, to counteract these effects. We analyse the environmental institutional framework and rural development plans, observing that institutional weaknesses have, in several instances, reduced the environmental benefit of technique and composition effects. We conclude with recommendations about how the Mexican agricultural sector might reap the environmental benefits of international agricultural trade.  相似文献   
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The end of the twentieth century was marked by a sea change in global governance in the realm of intellectual property rights (IPRs). Whereas countries historically retained substantial autonomy with regard to what they defined as intellectual "property" and the rights granted to the owners of intellectual property, the 1990s witnessed the establishment of new global obligations regarding national practices. This paper focuses on the case of software "piracy" to assess the mechanisms by which the new global obligations for the treatment of IPRs are transmitted from the international to the national levels. We first consider a set of national-level factors that many scholars have shown to be important determinants of IPR policy. We then supplement the standard emphasis on domestic factors with an analysis of new transnational factors: countries' multilateral obligations under the World Trade Organization's (WTO) Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPS) and bilateral pressures from the United States to increase the protection of IPRs. Population-averaged panel data models are used to assess the effects of these national and transnational determinants on levels of software piracy in 80 countries from 1994 to 2002. Our results indicate that membership in the WTO and bilateral pressures from the United States—particularly pressures that offer reciprocal concessions—lead to substantial increases in levels of protection in rich and poor countries. There is, in short, a new international political economy of intellectual property.  相似文献   
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