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201.
Huestis and Cone reported in [J. Anal. Toxicol. 22 (1998) 445] that serial monitoring of Delta9-THC-COOH/creatinine ratios in paired urine specimens collected at least 24h apart could differentiate new drug use from residual Delta(9)-THC-COOH excretion following acute marijuana use in a controlled setting. The best accuracy (85.4%) for predicting new marijuana use was for a Delta(9)-THC-COOH/creatinine ratio > or = 0.5 (dividing the Delta9-THC-COOH/creatinine ratio of specimen no. 2 by the specimen no. 1 ratio). In previous studies in this laboratory [J. Anal. Toxicol. 23 (1999) 531 and Forensic Sci. Int. 133 (2003) 26], urine specimens were collected from chronic marijuana users > or = 24 h or > = 48 h apart in an uncontrolled setting. Subjects with a history of chronic marijuana use were screened for cannabinoids with the EMIT II Plus cannabinoids assay (cut-off 50 ng/ml) followed by confirmation for Delta9-THC-COOH by GC-MS (cut-off 15 ng/ml). Creatinine was analyzed as an index of dilution. The objective of the present study was to evaluate whether creatinine corrected specimens could differentiate new marijuana or hashish use from the excretion of residual Delta(9)-THC-COOH in chronic marijuana users based on the Huestis 0.5 ratio. Urine specimens (N=376) were collected from 29 individuals > or = 96 h between urine collections. The mean urinary Delta9-THC-COOH concentration was 464.4 ng/ml, mean Delta9-THC-COOH/creatinine ratio (ng/(ml Delta9-THC-COOH mmoll creatinine)) was 36.8 and the overall mean Delta9-THC-COOH/creatinine ratio of specimen 2/mean Delta9-THC-COOH/creatinine ratio of specimen 1 was 1.37. The Huestis ratio calculation indicated new drug use in 83% of all sequentially paired urine specimens. The data were sub-divided into three groups (Groups A-C) based on mean Delta9-THC-COOH/creatinine values. Interindividual mean Delta9-THC-COOH/creatinine values ranged from 4.7 to 13.4 in Group A where 80% of paired specimens indicated new drug use (N=10) and 20.4-39.6 in Group B where 83.6% of paired specimens indicated new drug use (N=7). Individual mean Delta9-THC-COOH/creatinine values ranged from 44.2 to 120.2 in Group C where 84.5% of paired urine specimens indicated new marijuana use (N=12). Correcting Delta9-THC-COOH excretion for urinary dilution and comparing Delta9-THC-COOH/creatinine concentration ratios of sequentially paired specimens (collected > or = 96 h apart) may provide an objective indicator of ongoing marijuana or hashish use in this population. 相似文献
202.
Presidential candidates regularly use crime issues to help win electoral support. Contrary to conventional wisdom, crime control
also became an issue in the 2000 presidential campaign. Despite decreasing crime rates, the debate was driven by public opinion.
Because the crime debate was fueled by perception rather than reality, it is argued that the symbolic nature of the debate
became important in providing reassurance to the American public. This finding points to the importance of symbolic rhetoric
by presidential candidates in appealing to voters and increasing public support. 相似文献
203.
Surveys with 94 administrators of supervised visitation programs, 51 family court judges, and 40 administrators of child protective services agencies provide a national picture of supervised visitation services, their utility, and areas of unmet need. Although the programs are perceived to fill an important need, they struggle to survive financially, particularly those that handle family court cases. In addition, because many programs operate without adequate access to the assessment and treatment services that some families need, judges frequently want visitation supervisors to assist them in determining suitable custody and visitation arrangements, a role that supervised visitation programs do not feel is appropriate. Many different types of entities provide effective supervised visitation services; many different service formats work. Architects of new programs should fashion services that use local resources to maximum advantage. 相似文献
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Murrell and Olson (1991) set forth the hypothesis that in centrally planned economies economic interests over time become fragmented as bureaus become more autonomous and form into narrowly-based distributional coalitions. As a consequence, the national leader's encompassing interest in economic growth becomes compromised and growth begins to slow. This paper provides the first direct test of the hypothesis that growing bureaucratic autonomy results in declining economic growth in centrally planned economies. 相似文献
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Jecker NS 《Journal of health politics, policy and law》1993,18(3):657-673
It is America's distinctive practice to tie private health insurance to employment, and recent proposals have tried to retain this link through mandating that all employers provide health insurance to their employees. My primary approach to these issues is neither economic, nor historical, nor political but ethical. After a brief historical overview, I outline a general approach to evaluating the ethical significance of linking the distributions of distinct goods. I examine whether an unjust distribution of jobs spoils justice in the distribution of health insurance, taking as a central example gender inequities in employment and exploring their impact on job-based health insurance. Second, I explore the possibility that justly awarding jobs guarantees justice in employment-sponsored insurance. However, linking the distributions of different goods remains problematic, because such links inevitably undermine equality by enabling the same individuals to enjoy advantages in many different distributive areas. Finally, I examine recent proposals to reform America's health care system by requiring all employers to provide health insurance to their employees. I argue that such proposals lend themselves to the same ethical problems that the current system does and urge greater attention to alternative reform options. 相似文献
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