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The current study was designed to gain a better understanding of the nature of the relationship between substance use and sexual risk taking within a community sample of women (N = 1,004). Using confirmatory factor analysis, the authors examined the factor structure of sexual risk behaviors and substance use to determine whether they are best conceptualized as domains underlying a single, higher order, risk-taking propensity. A 2 higher order factor model (sexual risk behavior and substance use) provided the best fit to the data, suggesting that these 2 general risk domains are correlated but independent factors. Sensation seeking had large general direct effects on the 2 risk domains and large indirect effects on the 4 first-order factors and the individual indicators. Negative affect had smaller, yet still significant, effects. Impulsivity and anxiety were unrelated to sexual health risk domains.  相似文献   
3.
Adherence to medications for chronic pediatric diseases decreases overtime. This randomized controlled trial evaluated a clinic-based, nurse-administered educational and behavioral intervention to prevent the anticipated drop in adherence to nonsteroidal medications among newly diagnosed patients with juvenile rheumatoid arthritis. Thirty-four participants completed the study (mean age = 8.44 years, SD = 3.96), including 19 in the experimental group and 15 in the standard-treatment (education) control group. There were significant group and Group x Time effects for adherence (assessed with an electronic monitor over a 13-month period) favoring the experimental group. In contrast, the groups did not differ significantly in disease activity or functional limitations. Factors that may have prevented detection of differences in these health parameters are dicussed.  相似文献   
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Recidivism data derived from various sources over a follow-up period of 1–11 yr, provided the basis for appraising the effectiveness of a comprehensive cognitive-behavioral treatment program for familial and nonfamilial child molesters. Unofficial records held by police and Children's Aid Societies proved to be the best data for estimating recidivism. These data revealed increases in recidivism with longer follow-up periods, but there were consistent advantages for the treated over the untreated patients. Men who had sexually abused the daughters of other people demonstrated the clearest treatment benefits. The younger offenders and those who had engaged in genital-genital contact with their victims were more likely to reoffend even if they were treated. Contrary to the expectations of behavior therapists, indices of deviant sexual preferences did not predict outcome.  相似文献   
6.
The purpose of this study was to assess both conceptual knowledge and classification skills in nonfluent and fluent aphasia by focusing on the aphasics' appreciation of class and function relations. The results illustrated that fluent and nonfluent aphasics appreciated both class and function relations. However, further study revealed that even though the fluent aphasic may know the function of an item, he is impaired in his ability to use this information. The nonfluent aphasics also illustrated this tendency not to use their knowledge about function, but to a lesser extent and without the consistency found in the performance of fluent aphasics.  相似文献   
7.
Two different types of stimulus objects, a live female quail artificially adorned with bright orange feathers and an inanimate toy dog, served as conditioned stimuli. For subjects in experimental groups, the conditioned stimuli were presented shortly before access to a sexually receptive normal female quail. For subjects in control groups, exposure to the conditioned stimuli was unpaired with copulatory opportunity. Subjects in the experimental but not in the control groups quickly came to approach the location of the conditioned stimulus objects. When an adorned female quail served as the conditioned stimulus, the conditioned approach behavior was controlled by a combination of the presence of the orange adornments and the visual cues of the head and neck of the female bird, and the approach behavior persisted as the adorned female moved to new locations. When the toy dog served as the conditioned stimulus, the conditioned approach behavior was limited to the spatial cues that surrounded the toy dog during conditioning trials. Although both types of stimulus objects evoked conditioned approach behavior, only the adorned female stimulus supported copulatory behavior. This last finding indicates that copulatory behavior can become redirected toward novel stimuli as a result of conditioning, but only under special circumstances. The results are consistent with the suggestion that appetitive components of reproductive behavior are more susceptible to conditioning than consummatory components. Possible reasons for this are discussed, together with implications of the results for the contribution of conditioning processes to sexual selection.  相似文献   
8.
Three severely mentally retarded adolescents were studied under discrete-trial procedures in which a choice was arranged between edible reinforcers that differed in magnitude and, in some conditions, delay. In the absence of delays the larger reinforcer was consistently chosen. Under conditions in which the smaller reinforcer was not delayed, increasing the delay to delivery of the larger reinforcer decreased the percentage of trials in which that reinforcer was chosen. All subjects directed the majority of choice responses to the smaller reinforcer when the larger reinforcer was sufficiently delayed, although the value at which this occurred differed across subjects. Under conditions in which the larger reinforcer initially was sufficiently delayed to result in preference for the smaller one, progressively increasing in 5-s increments the delay to both reinforcers increased percentage of trials with the larger reinforcer chosen. At sufficiently long delays, 2 of the subjects consistently chose the larger, but more delayed, reinforcer, and the 3rd subject chose that reinforcer on half of the trials. These results are consistent with the findings of prior studies in which adult humans responded to terminate noise and pigeons responded to produce food.  相似文献   
9.
A cost-benefit analysis of demand for food.   总被引:20,自引:17,他引:3       下载免费PDF全文
Laboratory studies of consumer demand theory require assumptions regarding the definition of price in the absence of a medium of exchange (money). In this study we test the proposition that the fundamental dimension of price is a cost-benefit ratio expressed as the effort expended per unit of food value consumed. Using rats as subjects, we tested the generality of this "unit price" concept by varying four dimensions of price: fixed-ratio schedule, number of food pellets per fixed-ratio completion, probability of reinforcement, and response lever weight or effort. Two levels of the last three factors were combined in a 2 x 2 x 2 design giving eight groups. Each group was studied under a series of six FR schedules. Using the nominal values of all factors to determine unit price, we found that grams of food consumed plotted as a function of unit price followed a single demand curve. Similarly, total work output (responses x effort) conformed to a single function when plotted in terms of unit price. These observations provided a template for interpreting the effects of biological factors, such as brain lesions or drugs, that might alter the cost-benefit ratio.  相似文献   
10.
There appears to be a strong relationship between mass media portrayals of violence and real-life violence itself. This article reviews the available literature on the effects of media treatment of sports violence; analyzes the theoretical explanations for this treatment; and makes proposals on how the problems of both sports violence and its media coverage may be remedied, with a particular focus on amateur hockey in Canada.  相似文献   
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