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21.
David Levy 《Public Choice》1989,60(2):177-184
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Baptista MJ Monsanto PV Pinho Marques EG Bermejo A Avila S Castanheira AM Margalho C Barroso M Vieira DN 《Forensic science international》2002,128(1-2):66-78
A sensitive analytical method was developed for quantitative analysis of delta(9)-tetrahydrocannabinol (delta(9)-THC), 11-nor-delta(9)-tetrahydrocannabinol-carboxylic acid (delta(9)-THC-COOH), cannabinol (CBN) and cannabidiol (CBD) in human hair. The identification of delta(9)-THC-COOH in hair would document Cannabis use more effectively than the detection of parent drug (delta(9)-THC) which might have come from environmental exposure. Ketamine was added to hair samples as internal standard for CBN and CBD. Ketoprofen was added to hair samples as internal standard for the other compounds. Samples were hydrolyzed with beta-glucuronidase/arylsulfatase for 2h at 40 degrees C. After cooling, samples were extracted with a liquid-liquid extraction procedure (with chloroform/isopropyl alcohol, after alkalinization, and n-hexane/ethyl acetate, after acidification), which was developed in our laboratory. The extracts were analysed before and after derivatization with pentafluoropropionic anhydride (PFPA) and pentafluoropropanol (PFPOH) using a Hewlett Packard gas chromatographer/mass spectrometer detector, in electron impact mode (GC/MS-EI). Derivatized delta(9)-THC-COOH was also analysed using a Hewlett Packard gas chromatographer/mass spectrometer detector, in negative ion chemical ionization mode (GC/MS-NCI) using methane as the reagent gas. Responses were linear ranging from 0.10 to 5.00 ng/mg hair for delta(9)-THC and CBN, 0.10-10.00 ng/mg hair for CBD, 0.01-5.00 ng/mg for delta(9)-THC-COOH (r(2)>0.99). The intra-assay precisions ranged from <0.01 to 12.40%. Extraction recoveries ranged from 80.9 to 104.0% for delta(9)-THC, 85.9-100.0% for delta(9)-THC-COOH, 76.7-95.8% for CBN and 71.0-94.0% for CBD. The analytical method was applied to 87 human hair samples, obtained from individuals who testified in court of having committed drug related crimes. Quantification of delta(9)-THC-COOH using GC/MS-NCI was found to be more convenient than GC/MS-EI. The latter may give rise to false negatives due to the detection limit. 相似文献
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Intention des Beitrages ist es, Geschlecht und Familie auf der Basis eines institutionenorientierten Lebenslaufansatzes neu zu durchdenken. Die Zentrierung auf gesellschaftliche Institutionen als Orte der Vermittlung von individuellem Handeln und sozialstrukturellen Bedingungen ermöglicht es, mikro-, meso- und makrosoziale Interdependenzen in den Mittelpunkt zu rücken und bisher zum großen Teil verdeckten, da indirekten Strukturierungen von Geschlechterverhältnissen auf die Spur zu kommen. Aus dieser Perspektive relativiert sich die in der Lebenslaufforschung dominierende Individualisierungs-These zugunsten der Erkenntnis, dass Individuen sich durch institutionelle Eigenlogiken untereinander vernetzt sehen, die sie in neue Zwickmühlen bringen. Der Beitrag von Lebenslauf-Institutionen zur Rekonstruktion einer Geschlechterordnung gerät zwar zunehmend in Widerspruch zu Anforderungen an das individuelle Management der eigenen Biographie, doch der relationale Bezug zwischen Institutionen scheint Familie und Geschlecht weder aus ihren subjektiven Verpflichtungsmustern zu entlassen, noch aus ihrer sozialstrukturellen Vermittlerrolle zwischen biographischen Optionen und inkompatiblen institutionellen Verfügbarkeits-Ansprüchen. 相似文献
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Empirical studies have found that policies aimed at reducing youth access to tobacco have been successful at increasing retail compliance, but their effects on actual tobacco use are mixed. This article presents a model of youth access policies that helps explain the apparently conflicting results in the extant literature, provides a framework for future empirical studies, and suggests implications for public policy. Our model highlights the interaction of components in a well-designed policy, including sufficient compliance checks, penalties, and community involvement. It also illustrates why it will be difficult to eliminate all of youth supply. Nonretail sources, such as borrowing or stealing from parents and siblings and purchasing from older peers through black markets, are an important component of youth supply and become more important as retail access is reduced. The analysis is limited to policies that affect the retail supply of cigarettes but suggests the need for other policies that affect the demand for cigarettes, such as taxes and cessation policies, in order to further reduce youth smoking rates. 相似文献
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This article aims to give an account of how refugees' familyrelations are constructed in exile. It is based on fieldworkconducted among Chechen asylum seekers living in a refugee campin the Czech Republic in April 2004. It argues that althoughtraditional norms defining women's and men's position in Chechenfamilies have often been transgressed in the actual experiencesof men and women in situations of emergency such as war, flightand life in the camp, they remain relatively unchanged at thelevel of refugees' ideal notions of femininity and masculinity.It also shows that the environment of the refugee camp provides,on the one hand, some opportunities for the increase of women'spower in the family and men's involvement in childcare and householdduties. But on the other hand, the assistance in the camp isbased on an undiversified and gender-blind perception and constructionof refugees as passive objects of aid, and latently sustainsgendered violence. 相似文献
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Page AK 《Journal of health law》2004,37(4):629-665
Human subjects research has been the focus of numerous controversies over the years. The dilemma lies between the potential harm to individuals who participate in research and the knowledge to be gained from the research study that might benefit society. When research is conducted in developing countries by researchers and sponsors from the United States and other industrialized countries, differences in history, culture, politics, wealth, and power between the countries give rise to unique challenges. In this Article, the author identifies several ethical issues to be considered when research is conducted in developing countries and provides the legal and ethical framework for their resolution. 相似文献