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21.
A gas chromatographic (GC) fingerprint method, based on the presence or absence of six congeners, was developed for illicit cocaine samples. The fingerprint utilizes the relative abundances of these congeners towards each other, disregarding cocaine as the main constituent, and can be expressed numerically or graphically in the form of pictograms for rapid visual comparison. The method can be applied directly to a solution of the sample in chloroform, without previous workup procedures. More than 70 unrelated samples were analyzed and a great variation was observed in the parameter composition. On the other hand, a remarkable similarity could be seen between related samples. The GC fingerprint method may be considered an important contribution for sample comparison, as is exemplified by a subdivision of the analyzed samples in different categories, based on the number and types of congeners found.  相似文献   
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This paper describes the governance system of Spanish listed firms in the early 1990's. Although the institutional setting of the Spanish Stock Exchanges differs little from other European national markets, we found important differences in several aspects of corporate governance. In particular, some of the standard mechanisms of control (e.g. boards and institutional shareholders) do not play an active role, whereas ownership is relatively concentrated. Moreover, power indices suggest that controlling blocs of large shareholders are very likely to form. We thus conclude that the ownership of shares is a pivotal mechanism in the governance of Spanish corporations.  相似文献   
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If categories of 'race' and nationality are social and historical constructions laden with irrefutable meaning and consequences, then ethnic identities, like any other forms of identity, are means to other ends that may or may not be particular. Twentieth‐century indigenist history in Brazil reveals how the cultural politics of indigenism and nationalism can coalesce in a tautological politics of identity that undermines individual liberty and democratic heterogeneity. The concepts 'post‐indigenism,'post‐nationalism' and 'post‐identity' point to the strategic suspension of the infinite heterogeneity of the political subject as a means to widen the ground of shared experience and common interests beyond the realm of hollow and oppressive essentialisms.  相似文献   
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Despite its difficulties and inconsistencies in framing those practices andconducts recently unveiled by the press and judicial investigations whichhave caused considerable public discontent, the penal definition ofcorruption still highlights an interesting conceptual diversity across spaceand time that should not be overlooked. Most official discussions about andreferences to corruption and its volume are still framed within these hardparameters. It is, therefore, important to look at the intricacies ofcorruption as a crime in order to understand the virtues and failures ofnational repressive efforts. While crime statistics are of limited use for itsmeasurement, they can nevertheless help to interpret the way corruptionhas been treated through repressive instruments cross-nationally over aperiod of time.The aim of this paper is to assess the dynamics of the various processes ofsetting and revising penal standards to the conduct of office holders and theresults observable from the application of corruption and related offencesacross countries with different legal traditions.  相似文献   
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While it is becoming increasingly evident that the post-Leninist state is experiencing a considerable decline in capacity and strength, Western analysts have been slow to address the situation analytically. This essay examines the reasons for the lack of attention paid to the state by former Sovietologists, and offers a new theoretical perspective on the Leninist and post-Leninist states. The utility of this perspective is subsequently demonstrated by applying it to the case of local government reform in Poland. The inability of the Polish reform to overcome the administrative weakness of the state demonstrates both the seriousness of the problem, and the need for greater “state” consciousness on the part of post-Sovietologists.  相似文献   
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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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