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71.
The impact of high temperatures (24 to 39 degrees C) and low to moderately high humidities (20 to 70%) on the applicability of TLC systems for drug identification was studied during a 6 month climatologic cycle in Burkina Faso (West Africa). In general, the Rf values as observed on the plates were found to be substantially affected as compared with values obtained at temperate climates. Some TLC systems were more affected than others and the largest deviations of up to 30 Rf units were at low humidities. Tropical conditions also had a negative effect on the reproducibility of Rf values. However, when an Rf-correction procedure was applied, using reference mixtures of known drugs on each plate, accuracy as well as reproducibility of the resulting Rfc values were drastically improved and data thus corrected were found to be compatible with existing TLC data bases developed under moderate climatological conditions. The impact of high to extremely high humidities (70 to 100%) remains to be investigated.  相似文献   
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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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Following the tradition of Joan McCord's work, this paper reviews longitudinal-experimental studies in criminology with community samples of at least 100 persons, follow-up periods of at least 5 years, personal interviews, and measures of offending. The main advantages of such studies are in investigating both the natural history of development (including the effects of risk/protective factors and life events) and the impact of interventions on offending. This paper also reviews advantages and problems of prospective longitudinal surveys, randomized experiments, and longitudinal-experimental studies in criminology. Four key longitudinal-experimental studies were conducted by Joan McCord, Richard Tremblay, Lawrence Schweinhart and David Olds. Other studies have been conducted, or are currently under way, but no criminological study has yet been published with several years of personal data on participants both before and after an intervention.Joan McCord Award Lecture given at the American Society of Criminology, Toronto, Canada.  相似文献   
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The link between resource deprivation and urban violence has long been explored in criminological research. Studies, however, have largely ignored the potential for resource deprivation in particular communities to affect rates of violence in others. The relative inattention is notable because of the strong theoretical grounds to anticipate influences that extend both to geographically contiguous areas and to those that, though not contiguous, share similar social characteristics. We argue that such influences—what we term spatial and social proximity effects, respectively—constitute a central feature of community dynamics. To support this argument, we develop and test theoretically derived hypotheses about spatial and social proximity effects of resource deprivation on aggregated and disaggregated homicide counts. Our analyses indicate that local area resource deprivation contributes to violence in socially proximate communities, an effect that, in the case of instrumental homicides, is stronger when such communities are spatially proximate. We conclude by discussing the implications of our findings for theories focused on community‐level social processes and violence, and for policies aimed at reducing crime in disadvantaged areas.  相似文献   
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Of War and Law     
Netherlands International Law Review -  相似文献   
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Eight homicidal youths were assessed for language disorders and psychiatric diagnoses using a battery of standardized language tests and the Diagnostic Interview for Children and Adolescents. Both language disorders and Diagnostic and Statistical Manual III-R psychiatric diagnoses were present in all subjects.  相似文献   
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