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The increased use and abuse of methadone in recent years has posed a problem of both its identification and quantitation in body tissues. Recent development of a radioimmunoassay for methadone appears to have solved the problem. In our hands the assay was extremely sensitive and specific. It also appears to be an excellent tool when quantitative estimates are to be obtained. Although it initially appears to be relatively expensive, the time saved in doing a complete tissue distribution equalizes the cost. It is hoped that other radioimmunoassays currently under development will prove as satisfactory.  相似文献   
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A survey of sex and birth control behavior of 51 male adolescents aged 15–17 was conducted utilizing a structured interview protocol. The purpose of the study was to describe male adolescent birth control behavior incorporating developmental issues, and to interpret the findings in light of what is known about female birth control behavior. Based on research with teenage females, three social influences were examined for their possible impact on male birth control behavior. A new operational definition ofmale effective birth control usage involving the effectiveness of the method and the consistency of its usage was developed. Findings similar to those obtained from research on females suggest that adolescent sexual partners may be the only direct social influence on adolescents' birth control usage. Results indicating differences from research with females suggest that in general: male birth control behavior is primarily self-oriented, males are more likely to be effective contraceptors with casual partners than with girl friends, males are more likely to communicate about sex and birth control with similar age peers than with family members and/or other adults, and that teen males view sex and birth control decisions as female decisions.He also conducts private psychotherapy, specializing in marital and family therapy. His doctorate from the University of Pennsylvania is from a unique joint program in marital/family therapy and sex education. His interests include sex roles and their impact on intimate relationships, adolescent development, and male sexuality. This article is based on his doctoral dissertation.faculty member in the Human Sexuality Program. Dr. Rose served as supervisor on Dr. Cohen's doctoral dissertation.  相似文献   
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This article proposes a new method for examining dynamic changes in thespatial distribution of a phenomenon. Recently introduced exploratoryspatial data analysis (ESDA) techniques provide social scientists with anew set of tools for distinguishing between random and nonrandom spatialpatterns of events (Anselin, 1998). Existing ESDA measures, however, arestatic and do not permit comparisons of distributions of events in the samespace but across different time periods. One ESDA method—the Moranscatterplot—has special heuristic value because it visually displayslocal spatial relationships between each spatial unit and its neighbors. Weextend this static cross-sectional view of the spatial distribution ofevents to consider dynamic features of changes over time in spatialdependencies. The method distinguishes between contagious diffusion betweenadjoining units and hierarchical diffusion that spreads broadly throughcommonly shared influences. We apply the method to homicide data, lookingfor evidence of spatial diffusion of youth-gang homicides acrossneighborhoods in a city. Contagious diffusion between neighboring censustracts is evident only during the year of peak growth in total homicides,when high local rates of youth-gang homicides are followed by significantincreases in neighboring youth- nongang rates. This pattern is consistentwith a spread of homicides from gang youth to nongang youth. Otherwise, theincreases in both youth-gang and youth- nongang homicides generally occursimultaneously in nonneighboring tracts.  相似文献   
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