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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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Kimberly de Beus 《Journal of criminal justice》2007,35(3):337
Studies of restorative justice programs continue to provide a review of restorative justice practice and impact. While this body of research is growing, many questions remain regarding the impact of restorative justice in reducing crime. By relying on individual and community-level data, the present study examined how offense type and poverty level influenced program completion and recidivism among juveniles in a restorative justice program. This study also examined the relationship between program completion and recidivism. Findings revealed that status offenders in the restorative justice program were more likely to complete the program and less likely to recidivate than status offenders in the comparison group. In addition, property offenders in the restorative justice program were less likely to recidivate than property offenders in the comparison group. Poverty level at the community-level had a significant influence in both program completion and recidivism. 相似文献
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Drug trade is widely seen as a phenomenon rather new to the Netherlands. However, at the beginning of the 20th century the Dutch pharmaceutical industries were already extensively involved in the production of both opiates and cocaine, and they went on exporting large quantities of these drugs after the Opium Act (1919) took force. Until the 1960s, arrests were not at all common, and these largely affected minority groups like Chinese opium smokers and black marijuana users. Since then, drug control efforts have increased by leaps and bounds. At first, cannabis was the main target; then the focus turned to heroin, and that was later joined by cocaine. This paper traces the history of the drug trade and drug control in the Netherlands, with emphasis on their development in Amsterdam. The conclusion is reached that, in spite of drastic changes in both drug trade and drug control, certain ideologies, constructs and strategies have remained remarkably stable. 相似文献
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Making a first sketch of philosophical issues arising fromEuropean Community law I want to present a series ofmore or less obvious, and more or less interrelated dilemmas,or even double binds.(i) Deepening the community becomes incompatible withwidening membership. (ii) National states seem bothnecessary for and obstructive in articulating transnationalproblems. (iii) The more democracy is needed as a warrantfor the public exercise of political power in Europe, themore the very concept of democracy on a European scaleevades understanding. (iv) European unity presupposes aunifying rule of law, while member states have radicallydifferent conceptions of this principle. (v) Even the verycore of European integration, the common market, is subjectto two conflicting and, indeed, incompatible doctrines ofcompetition. In explaining the nature of each dilemma I willtry to take my cue from the Maastricht Treaty wherever thisseems suitable. Then I will elaborate on the jurisprudentialproblems involved in it. Finally, each section will be closedby an attempt to state the nature of these problems inphilosophical terms. 相似文献