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921.
Prevalence and Predictors of Sexual Risks Among Homeless Youth 总被引:1,自引:0,他引:1
This study examined prevalence of sexual risks among homeless adolescents and described factors associated with those risks. Community-based outreach methods were used successfully to access this difficult-to-reach population. The sample included 203 homeless youth aged 15–22 recruited from community sites. Questionnaire items addressed demographics, sexual behaviors, alcohol/drug use, STI history and testing, and pregnancy history. In cross-sectional analysis, 58.7% of males and 75.6% of females reported recent sexual intercourse. Of those, one third of males and half of the females used no barrier method with at least one partner. Both gender (female) and race/ethnicity (non-Black) were associated with having intercourse without a barrier contraceptive method. Over one fifth reported a history of survival sex or receiving money, drugs, clothing, shelter, or food for sex. These results show disturbingly high rates of a number of sexual risks, reinforcing the need for targeted interventions with this highly vulnerable population. 相似文献
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Based on considerable previous research, a four-factor model of adolescent concerns was proposed. Data on concerns were collected from 439 adolescents together with demographic data. A hierarchy of concerns was established based on mean ratings, and sex and age differences were reported. The data were factor analyzed into four principal components and were tested for the goodness of fit to the proposed model using linear structural relationships (LISREL) techniques by the method of maximum likelihood. The data fit the model very well (goodness of fit index=.958). The implications of these findings for further research and theories of adolescent development are discussed generally.Received his B.Sc and M. A. from the University of British Columbia, and his Ph.D. from the University of Alberta. His main interests are in development, and in quantitative methods in psychology and education.Graduate student currently completing a master's degree in counseling psychology. His main interest is in working with adolescents. 相似文献
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The authors have reported a macro- and microscopic study of brain lesions in 120 victims of fatal road traffic accidents, independent of the survival time. Diffuse vascular injury (DVI) was found in 14 patients (11.7%). All patients with DVI died within 24 h after the accident. The 14 patients with DVI also showed severe (Grade 2 or 3) diffuse axonal injury (DAI). Since DVI is restricted to road traffic accidents and incompatible with life, the high frequency observed in our series could be explained by the fact that all 120 patients were victims of road traffic accidents, and 69.2% had died within 24 h after the accident. The association between DVI and severe DAI (Grades 2 and 3) suggests that both lesions depend on the same mechanism, with the degree of axonal and vascular damage being determined by the intensity of the head acceleration. Our results show a relationship between DVI and DAI that suggest there may be a spectrum or at least a continuum between these entities as distinct from DVI being a separate entity. 相似文献
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Castellblanch R 《Journal of health politics, policy and law》2003,28(1):109-132
A comparison of the Vermont and Maine cases of attempting to control pharmaceutical prices in the year 2000 shows that the Maine legislators were more successful in challenging pharmaceutical industry political power. This comparison shows that challenging the industry was aided by (1) mobilizing public support through grassroots organizations, (2) including independent pharmacists in negotiations over the legislation, and (3) developing state purchasing power leverage. 相似文献
930.
Evaluating the informative power of Y-STRs: a comparative study using European and new African haplotype data 总被引:4,自引:0,他引:4
Male individuals from Maputo (Mozambique) were sampled and 18 Y-STRs were typed: the nine currently used to define the "minimal haplotype" employed in the European, American and Asian "Y-STR Haplotype Reference Databases", as well as the recently described DYS434, DYS437, DYS438, DYS439, DYS460, DYS461, GATA A10, GATA C4 and GATA H4. Allele and haplotype frequencies were estimated in a sample of 112 individuals, where it was possible to define 101 haplotypes, with an observed haplotype diversity (HD) of 0.9973. Allele diversity varied between 0.0179 and 0.9220, DYS385 showing the highest level of polymorphism and DYS392 the lowest. When considering only the most recent Y-STRs, the degree of diversity varied between 0.4011 (DYS438) and 0.6910 (GATA C4), except for DYS434 and DYS437 where a very low diversity was observed (0.0700 and 0.0526, respectively). When analysing the same 112 individuals for the nine Y-STRs included in the minimal haplotype, 78 haplotypes were distinguished with a corresponding observed diversity of 0.9884, a considerably lower value than those for Northern Portugal (n=208; HD: 0.9925) and Macao (n=63; HD: 0.9990). Concerning all 18 Y-STRs studied in this population, the observed diversity demonstrates their usefulness in forensic applications, with the exception of DYS434, DYS437 and DYS392. However, since the informative power of a marker has to be judged in haplotype context, a simple software, allowing the evaluation of the increase of HD through the addition of any combination of new markers to the minimum haplotype was designed. The statistical approach devised, demonstrates that an increment on HD is more rapidly obtained for the Mozambican database when adding GATA A10 or DYS439, DYS460, GATA C4, DYS461 or GATA H4, in this order, to the minimal haplotype. DYS434, DYS437 and DYS438, in conjunction with all the other 15 Y-STRs, do not contribute to an increment on HD. When applying the same approach to an European sample (Northern Portugal), the first three Y-STR choices coincide, but the next order of markers are GATA H4, then DYS437 and finally DYS461. In this sample, DYS434, DYS438 and GATA C4 do not increment HD any further. 相似文献