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81.
Low concentrations of THC and 11-hydroxy-THC in serum samples are often claimed not to result from recent cannabis use. Prediction of time of exposure is difficult, especially if distinctive features of drug use could not be observed. Therefore, the aim of the study was to investigate the presence of THC and 11-hydroxy-THC in serum samples as well as to obtain preliminary data on the analyte profile for a time window of 24-48 hours after discontinuation of cannabis smoking. Serum samples from heavy (n = 12, > 1 joint/day), moderate (n = 11, < or = 1 joint/day) and light (n = 6, < 1 joint/week) smokers of cannabis were analyzed for THC, 11-hydroxy-THC and free THC-COOH by GC/MS as well as for glucuronidated THC-COOH by LC/MS-MS. The blood samples were collected 24-48 hours after abstaining from cannabis use. Additionally, 8 specimens were obtained from persons after discontinuation of the drug for more than 48 hours. During collection of the blood samples, distinctive effects due to drug use could not be observed. For heavy users of cannabis, THC was detectable in 8 samples, and in 5 cases both biologically active compounds, THC and 11-hydroxy-THC, were present (1.3-6.4 ng THC/mL serum, 0.5-2.4 ng 11-hydroxy-THC/mL serum). Among moderate users, in 1 sample 1.8 ng THC/mL serum and 1.3 ng 11-hydroxy-THC/mL serum were determined, and another sample was tested positive with low concentrations close to the limit of detection. In serum samples of light users both analytes could not be detected, indicating that in those persons a positive finding of THC and 11-hydroxy-THC may rather result from recent consumption than from cannabis use 1 or 2 days prior to blood sampling. The concentrations of THC-COOH and its glucuronide covered a wide range in all groups of cannabis users. However, there was a trend to higher concentrations in heavy users compared to moderate users, and the mean concentration was smaller in light smokers than in moderate smokers. Overall, the findings indicated that data from pharmacokinetic studies should be supplemented by data obtained from "real-life" samples.  相似文献   
82.
This paper discusses results of a supercritical fluid extraction-gas chromatography/mass spectrometry (SFE-GC/MS) study of small samples ( 100 microg to 1 mg) of human scalp hair. The method offers a number of benefits including greater sensitivity than liquid extraction methods because the entire extractable mass is transferred to the analytical system, compared with only a few percent from a conventional liquid extraction/injection. The project's goals were to determine if SFE-GC/MS analyses of the surface-extractable components of an individual's hair yield consistent chemical profiles and to investigate if the profiles are sufficiently different to distinguish them from those of other individuals. In addition, the mtDNA sequences from ten of the same individuals used in the SFE-GC/MS study from four family units were determined, and, while the families were distinguishable, the maternal relations yielded identical sequences. In tandem, SFE-GC/MS and mtDNA techniques may provide valuable complementary data from forensic hair samples.  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   
84.
Aboriginal Australians have traditionally enjoyed little protection from the law. The matter of land has been at the heart of white settler/Aboriginal relations since the nation was first founded. It is only recently that recognition has been given to the land rights of Australian indigenous people. This recognition was finally made at the property law level in 1992 through the High Court decision in Mabo v. Queensland (n. 2) ([1992] 175 CLR 1). The 1993 High Court decision in The Wik Peoples v. Queensland ([1996] 71 ALJR 173) reinforced that recognition. It did so through the principle that pastoral lessees' and native title holders' rights might co-exist except that, in the event of any inconsistency, the pastoralists' rights were to prevail, provided pastoral activity was being pursued. The most recent legal change is the parliamentary revision of the Native Title Act so that the Wik co-existence principle was put to rest, mainly through permitting the State governments to upgrade pastoral holdings to a form of freehold, thus immunising them from native title claims, and minimising the payment of compensation. In this paper we argue that the country must consider what has been lost in this about-turn from the recognition of native title to land in Mabo . We argue that the nation must consider the emphases in the Mabo judgments upon the significance of international law and the need for the common law not to be locked into a racist past. From that point, we contend for the need to recognise not only native title to land but what lies beyond that: indigenous political and human rights.  相似文献   
85.
This study was concerned with verbal behavior in a discussion group setting. Two groups of nine tenth grade boys met for eight sessions in an unstructured group discussion. Verbal behavior was coded using a modified version of Bales' interaction process analysis. The most frequently coded behaviors were Giving Opinions, Dramatizing, and Expressing Anxiety. Verbal participation and initiation were positively correlated (r=0.88). Slightly more of the interaction was coded as affective than cognitive. Positive ratings of the group experience by theSs are contrasted to behavioral evidence of discomfort and anxiety. Inferences are drawn about the boys' lack of interpersonal skills and their use of fantasy to support their masculine sex role.Received Ph.D. from the University of Michigan in developmental psychology. Current research interests include the development of interpersonal skills and changes in social interaction at various stages in the family cycle.  相似文献   
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Group Identity and Alienation: Giving the We Its Due   总被引:3,自引:0,他引:3  
The purpose of this paper is to argue for greater understanding and valuing of group affiliation and the formation of allegiances to groups during early adolescence. An overemphasis on themes of individual identity, self-reliance, and autonomy as the developmental trajectory of adolescence leads to a lack of attention to the positive, normative mechanisms that permit young adolescents to achieve a sense of belonging and connection. We propose developmental processes which underlie the capacity for reflection about groups, 4 basic components of group identity, and 6 propositions about new capacities that emerge as young adolescents struggle with the dialectic between group identity and alienation. The final section suggests opportunities that can emerge through a more appropriate emphasis on group identity as a valued, normative aspect of development during the early adolescent years.  相似文献   
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