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991.
The occurrence of pallidal lesions with or without other hypoxic/ischaemic brain injuries was evaluated in 100 intravenous (i.v.) heroin addicts. The brains were collected consecutively from forensic autopsies during the period from January 1995 to June 1996. The autopsies were required by the police and performed at The Institute of Forensic Medicine, The National Hospital, Oslo. There were 21 women and 79 men, median age 32 (range 21-47) and 34 (19-60) years, respectively. Of 38 brains with abnormalities, twenty-five cases showed isolated or combined lesions of hypoxic/ischaemic origin. Pallidal lesions were found in nine brains; six lesions were old, one was subacute (a couple of weeks), and two were part of recent, generalized hypoxia/ischaemia. Six persons had old infarcts in the hippocampal formation, and one of them in combination with old pallidal infarcts. In seven brains small and old infarcts were found in watershed areas in the cerebellum. Between five and ten percent of i.v. heroin addicts might have pallidal infarcts, either as the sole lesion, or combined with other manifestations of hypoxic/ischaemic brain injury. This might give severe mental disturbances in the affected persons.  相似文献   
992.
993.
A 53-year-old woman who was diagnosed as suffering from depression was found dead in her bed. The autopsy revealed no morphological changes sufficient to explain death. Toxicological analysis was performed and the drugs trimipramine (2.33 mg/l), citalopram (4.81 mg/l) and zolpidem (0.07 mg/l) were identified in the femoral blood. A combined drug intoxication resulting in synergistic effects to cardiovascular disorders was proposed as the cause of death. An acute overdose and suicide was suggested by calculation of the parent drug to main metabolite ratios in femoral blood and liver tissue. The trimipramine to desmethyltrimipramine ratios were calculated to be 2.06 and 3.18, the citalopram to desmethylcitalopram ratios were 1.96 and 2.02.  相似文献   
994.
995.
The U.S. Census Bureau recently released new, experimental measures of poverty based on a National Academy of Sciences (NAS) panel's recommendations. This article examines the effects of the experimental measures on poverty rates among persons aged 65 or older in order to help inform policy debate. Policymakers and analysts use poverty rates to measure the successes and failures of existing programs and to create and defend new policy initiatives. The Census Bureau computes the official rates of poverty using poverty thresholds and definitions of countable income that have changed little since the official poverty measure was adopted in 1965. Amid growing concerns about the adequacy of the official poverty measure, a NAS panel undertook a study of the concepts, methodology, and data needed to measure poverty. The panel concluded in its 1995 report that the current measure no longer provides an accurate picture of relative rates of poverty for different groups in the population or of changes in poverty over time. The panel recommended changes in establishing the poverty thresholds, defining family resources, and obtaining the required data. The Census Bureau report shows how estimated levels of poverty would differ from the official level as specific recommendations of the NAS panel are implemented individually and how estimated trends would differ when many recommendations are implemented simultaneously. It computes nonstandardized and standardized poverty rates. (The latter constrains the overall poverty rate under the experimental measures to match the official rate.) This article reports poverty rates that have not been standardized and provides considerably more detail than the Census report about the effects of the experimental measures on poverty among the aged. It examines the effects of changing the poverty thresholds and the items included or excluded from the definition of available resources. It also explores the effects of the experimental measures on persons aged 65 or older by age group, gender, race and ethnicity, and marital status. Results indicate that: Poverty rates in 1997 for persons aged 65 or older under the experimental NAS poverty measure are 17.3 percent, compared with 10.5 percent under the official poverty measure. This 65-percent increase is largely driven by the NAS-based measure's subtraction of medical out-of-pocket (MOOP) expenses from resources. Under the NAS-based measures, poverty rates increase for all major groups of older persons, and increase the most for groups for whom the incidence of official poverty is the lowest. The experimental NAS poverty measure shows narrower differences between genders, racial and ethnic groups, and among persons of different marital statuses than the official poverty measure. For example, white Hispanic women aged 65 or older have poverty rates that are 450 percent higher than those for white non-Hispanic men under the official poverty measure and 181 percent higher under the NAS measure. The NAS-based measure's subtraction of MOOP expenses from resources has a disproportionate effect on poverty rates among non-Hispanic whites and men as compared with other groups. However, changes in relative poverty between groups appear to be most influenced by the NAS midpoint equivalence scale. Because this scale decreases poverty rates for persons who live alone or with unrelated individuals and increases them for persons who live with others, poverty rates differ meaningfully under the NAS and official measures among demographic groups. This article highlights issues concerning the elements of the experimental NAS poverty measure that are particularly important to the measurement of poverty among the aged population. Results suggest that the research community's future efforts to refine, enhance, and build upon the NAS panel's recommendations will yield important insights about poverty among the older population.  相似文献   
996.
Kübler  Dorothea 《Public Choice》1999,101(1-2):85-107
In response to the analysis of bureaucracies and the finding of inherent inefficiencies, public choice theory argues for an increase in competition by contracting out government services and deregulation. The paper explores the effect of coexisting public and private employment services in a model with private information of the worker about her ability and unobservable effort choice. The employer's use of an efficient unemployment exchange and an efficient private agency may lead to optimal screening with first best contracts. This is due to the assumption that good types of workers lose more human capital than bad types in periods of unemployment or mismatch. In contrast to standard screening contracts, a bad type of worker earns an information rent if the employment exchange is inefficient, but the employer chooses not to use the private agency for good types.  相似文献   
997.
Dow  Jay K. 《Political Behavior》1999,21(4):305-324
This study estimates a model of voter choice for the first and second ballots of the 1995 French Presidential election. Its objective is to characterize the relative importance of traditional bases of French voter choice such as social class relative to campaign issues and voter evaluations of the economy. The study also seeks to identify candidate-specific bases of voter choice. Multinomial logit analysis of voter choice among the four leading candidates reveals a stronger role for campaign issues than previous studies suggest. Voter-candidate ideological proximity is the strongest predictor of first and second ballot choice, followed by voter perceptions of candidate ability to address unemployment and political corruption. Demographic variables have limited explanatory power in both the first and second ballot models. The parameter estimates demonstrate considerable differences in the bases of voter choice across candidates, with the bases of voter choice for National Front leader Jean-Marie le Pen most distinct from those of the remaining candidates.  相似文献   
998.
999.
THE TRAIN     
  相似文献   
1000.
This study examines the association of self-perceptions with sixth to eighth graders' exposure to mixed-sex and dating contexts. It contrasts two hypotheses: the stress hypothesis, which suggests that the transition to romantic relationships will be associated with declines in self-esteem, especially for girls, and the leisure hypothesis, which suggests that movement into a desired role in an emotionally positive social context will be associated with positive emotions and higher self-esteem. Results indicate that adolescents experience mixed-sex settings positively, and that comfort with the other sex (for girls) and more time spent with the other sex (for boys) are predictive of more positive self-perceptions. Activity diary data suggest that these differences are due to differences in the emotional climate of same- and mixed-sex settings, rather than to the activities adolescents engage in with same- and mixed-sex groups. Dating boys who are less interested in dating experience lower self-esteem. Results are discussed in light of the transitional nature of mixed-sex relationships in early adolescence and the preparatory role played by same-sex friendships.  相似文献   
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