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Congress and the Drug Enforcement Administration have assigned certain psychoactive substances to one of five schedules, based on assumed or demonstrated abuse potential. Although formidable difficulties exist in assessing the hazards of drug use, some of these assignments do not appear consistent with empirical estimates. This mismatch of assignment and abuse potential -possibly due to "radical" political ideology - obscures significant differences in drug effects, and therefore stifles meaningful public participation in evaluating the benefits, risks, and proper use (if any) of available psychoactive substances.  相似文献   
144.
The analysis of naphthenic acid revealed that they may be used for tin detection in the cadaveric material due to their high complex-forming ability. Method of extraction-atomic absorption tin determination in human organs was developed on the basis of naphthenic acid use. Modified method which differs from the common one by higher sensitivity and selectivity is presented.  相似文献   
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Alas poor yorick     
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147.
Although past research has developed scales for the incidence, prevalence, and fear of student-on-student victimization (SSV), little is known about the scaling of perceived risk (i.e., the cognitive appraisal of the chances of experiencing SSV). Hence, this study examined self-report survey data for the perceived risk of SSV as measured in the Adolescent Index for School Safety (AISS). Children in grades 7 through 10 (n=337) in a single Florida public school completed the AISS. Factor analyses using Maximum Likelihood Estimation with Oblimin Rotation identified nine unique factors for perceived risk. Reliability analyses found standardized Cronbach Alphas that ranged from .64 to .91, and seven out of the nine identified scales were above .80, which suggested good to excellent internal consistency. Future research should examine the content validity, construct validity, and predictive validity for the AISS and other self-report surveys of SSV dynamics. This publication was made possible by a grant [#97-MU-FX-KO12 (S-l)] from the Office of Juvenile Justice and Delinquency Prevention (O.J.J.D.P.), United States Department of Justice (U.S.D.O.J.). This grant is administered through the Hamilton Fish National Institute on School and Community Violence at George Washington University. This specific study was developed and implemented by staff at: 1) East Carolina University’s Department of Criminal Justice; and 2) Florida State University’s Center for Educational Research and Policy Studies. All points of view and opinions in this paper are those of the authors and do not necessarily represent the official position or policies of East Carolina University, Florida State University, the Hamilton Fish National Institute on School and Community Violence, the O.J.J.D.P., or the U.S.D.OJ. The authors would also like to thank Dr. Bill Doerner and Jennifer Jolley for their support, editorial feedback, and insightful comments regarding earlier drafts of this paper.  相似文献   
148.
All records from the Danish Medicolegal Council concerning drivers suspected for drug influences were examined for the 5 year period 1981-1985. 461 records were included, 62 women and 399 men. In 250 cases drugs from more than one of ten groups had been taken thus making 786 combinations of drug/driving. The major drug group was benzodiazepines, accounting for 65% of all drug intake. Opioids also contributed substantially, found in 38% of the cases. A traffic accident had occurred in 180 (39%) of the records. Drivers who had been taking antidepressives were involved in an accident in 67%, significantly above the mean. For benzodiazepines, the corresponding percentage was 43%, while for opioids it was only 23%, significantly below the mean. This striking difference has been demonstrated in most of the studies concerning drugs in traffic. It may support the hypothesis that opioids do not necessarily make driving dangerous, as do antidepressives, barbiturates and especially benzodiazepines.  相似文献   
149.
In the current study the objective was to find to what extent a reliable determination of age at death is made possible by establishing the degree of aspartic acid racemization in the dentin of teeth. The results of the investigation of 46 teeth are in agreement with the values found by other authors. The method presented makes a reproducible and accurate estimation of age possible. We intend to elaborate and improve this promising method for determination of age at death. The relevant points are presented here.  相似文献   
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