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An apparatus was developed to study social reinforcement in the rat. Four Long-Evans female rats were trained to press a lever via shaping, with the reinforcer being access to a castrated male rat. Responding under a fixed-ratio schedule and in extinction was also observed. Social access was found to be an effective reinforcer. When social reinforcement was compared with food reinforcement under similar conditions of deprivation and reinforcer duration, no significant differences were observed.  相似文献   
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Research has demonstrated links between sexual abuse and disordered eating among women in college student and mental health samples. Little is known about such relationships among women from other samples or the relationship between other forms of childhood abuse as well as disordered eating (vomiting, starvation, laxative abuse). Prevalence of disordered eating was significantly higher among women who indicated a perceived childhood history of sexual, physical, or emotional abuse or who had personally witnessed violence.  相似文献   
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Considerable scientific evidence demonstrates the reduction in risk for neural tube defects (NTDs) associated with maternal preconceptional folic acid supplementation. The National Society of Genetic Counselors (NSGC) endorses the U.S. Public Health Service recommendations for folic acid supplementation at the 0.4 mg level for women in the general population and at the 4.0 mg level for women at high or increased risk for NTD pregnancies for at least 4 weeks prior to active pursuit of conception. We encourage targeted educational efforts and surveillance to assess results of this dietary supplementation. The NSGC further urges the Food and Drug Administration to fortify staple foodstuffs with folic acid for a population-based approach to minimize the number of NTD births.  相似文献   
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The influence of subject and interviewer characteristics on the reliability of self-reports of alcohol consumption among young adults was investigated. Data were gathered from black and white college students of both sexes (N's=24) using a time-line procedure. The results snowed that these young adults provided highly reliable self-reports regarding their use of alcohol. Test-retest correlations for a criterion interval of 90 days were .96, .93, and .97 for the numbers of abstinent, moderate-drinking, and heavy-drinking days, respectively. Analyses also showed that white female subjects generally provided more reliable reports of abstinent and heavy-drinking days and that white female interviewers gathered more reliable reports across the three drinking disposition categories. These findings suggest that nonalcoholic young adults' retrospective reports of their drinking behavior can be reliably assessed using the time-line methodology. Future research is required to determine the validity of these self-reports and to understand the differential influence of subject and interviewer characteristics on the levels of reliability found.  相似文献   
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Factor analyses were carried out on the responses of 115 cigarette smokers to the Smoking Questionnaire of Russell et al. (1974), to the Situational Smoking Questionnaire of Frith (1971) and to certain items of a biographical smoking questionnaire. In the analysis of Russell's questionnaire, a set of six factors was extracted, bearing some resemblance to the six factors found by the authors of the questionnaire, although the matching of factors was by no means perfect. However, the results did support Russell et al.'s finding of a major dimension of degree of dependence upon cigarettes, together with an orthogonal factor contrasting pharmacological with non-pharmacological dependence. The analysis of the Situational Smoking Questionnaire confirmed Frith's finding that the first principal component represented a general desire for cigarettes while the second contrasted desire to smoke in high- and low-arousal inducing (or stressful and relaxing) situations; and these two components corresponded fairly well with the first two components extracted from Russell's questionnaire, pharmacological dependence being associated with smoking in stressful situations.  相似文献   
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An adaptive psychometric procedure that places each trial at the current most probable Bayesian estimate of threshold is described. The procedure takes advantage of the common finding that the human psychometric function is invariant in form when expressed as a function of log intensity. The procedure is simple, fast, and efficient, and may be easily implemented on any computer.  相似文献   
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