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71.
Bonnie Jeanne Baty Leslie Cohen Lorna Phelps Marcy C. Speer Pamela Stengel Lori Williamson-Kruse 《Journal of genetic counseling》1996,5(3):139-145
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
72.
Sex Roles - Rape is an underreported and underconvicted crime. Therefore, many highly sexually aggressive men are missed by research employing judicial identification for sample selection. The... 相似文献
73.
Leonard Berkowitz 《Journal of personality》1978,46(2):299-310
The present experiment attempted to integrate the research on helpfulness in which subjects work for someone else in an artificial laboratory setting (Berkowitz & Daniels, 1963; Berkowitz, 1972) with the bystander-intervention-in-emergencies studies often carried out under more realistic conditions (e.g., Latané & Darley, 1970; Schwartz & Clausen, 1970; Clark & Word, 1972). Fifty-six university women in a 2 × 2 factorial design were led to think they were working for a same-sex peer who could win a cash prize, although there was “nothing in it for them.” Half were told that the other's chance of getting the prize was greatly dependent upon their effort while the remaining participants were informed that the other did not need their-work very much. Moreover, half of the subjects thought they were the only ones working for the other whereas the remaining people believed there were two other co-workers and that the output from all three would be averaged. It was expected that the participants would feel the greatest personal responsibility to help the other and would work hardest for her when she was greatly dependent upon their productivity and they were the only worker, while the subjects would feel the lowest level of personal responsibility for their peer and would be least helpful to her when she was not particularly dependent upon them and there were two other co-workers. The findings are generally in accord with these expectations. 相似文献
74.
Leonard H. Epstein Gene G. Abel Frank Collins Lynn Parker Paul M. Cinciripini 《Behaviour research and therapy》1978,16(3):153-160
The relationship between levels of frontalis muscle activity and self-reports of pain was evaluated in two studies. In Study I frontalis muscle activity and self-reports of pain collected during biofeedback treatment of muscular contraction headache clients were correlated. In Study II frontalis EMG activity was increased and decreased using biofeedback techniques while concurrent reports of headache pain were recorded. The results of Study I indicated a significant relationship between EMG activity and reported headache pain for only two of the five subjects studied. The biofeedback procedures in Study II were associated with reliable increases and decreases in EMG activity. Concordance between EMG and pain reports occurred only during the EMG increase condition. Overall correlations were significant for one of the 2 subjects. The results suggest that EMG activity may not be sufficient to account for pain reports in all chronic headache clients, and variables other than EMG activity may be influencing reports of pain in some patients. 相似文献
75.
Leonard S. Feldt 《Psychometrika》1980,45(1):99-105
In measurement studies the researcher may wish to test the hypothesis that Cronbach's alpha reliability coefficient is the same for two measurement procedures. A statistical test exists for independent samples of subjects. In this paper three procedures are developed for the situation in which the coefficients are determined from the same sample. All three procedures are computationally simple and give tight control of Type I error when the sample size is 50 or greater.The author is indebted to Jerry S. Gilmer for development of the computer programs used in this study. 相似文献
76.
77.
Previous studies have found that a nonspecific visual event occurring at the fovea 50–150 msec after the onset of a peripheral target delayed the initiation of the saccade to that target. The present studies replicated and extended this finding by studying the effects of both visual and auditory warning signals, by examining the effects of onset and offset warning on manual response latency, and by investigating the effects of presenting the warning events in the periphery of the visual field. The results indicated that the interfering effects occur with visual but not auditory stimuli, with saccades but not motor responses, and when the visual warning event occurs either foveally or in the subject’s periphery. Implications for the processes involved are discussed. 相似文献
78.
79.
The present study examined the role of permissive and nonpermissive cues in mediating the relationship between exposure to erotica and aggression. Male subjects viewed either neutral slides with a silent female or erotic slides with a female who made permissive, nonpermissive, or no comments about the slides. The males rated the slides and subsequently rated the female confederate. Male subjects were then given an opportunity to administer their choice of several intensities of shock to the female in a competitive reaction-time task. Subjects in the permissive cues condition rated the erotic slides as more arousing, saw the female as more reasonable and accepting, and selected more intense shocks for the female than did subjects in the other conditions. One explanation of these results is that permissive cues in the presence of erotica led the male to believe that other normally inappropriate behaviors would be tolerated. 相似文献
80.
The present research was designed to test the hypothesis that perceptions of consensus about the collective experience of psychological problems, as well as the distinctive presence of a community disaster, would affect attributions of externality about such problems. Specifically, it was hypothesized that (1) higher levels of consensus would be associated with greater external attributions of causality, (2) attributions would be more external if the problem began after the disaster (high distinctiveness) than before the disaster, and (3) the occurrence of the disaster would magnify the positive relationship between high consensus and external causality attributions, because of the presence of a distinctive and salient external event. These hypotheses were tested with victims of a flash flood. Results supported the interaction prediction (Hypothesis 3) for the problem of depression, but not for anxiety. In addition, for depression and anxiety, greater consensus was indirectly associated with greater externality, regardless of distinctiveness (Hypothesis 1). However, for somatization, none of the hypotheses were supported. The results are discussed in terms of the applied implications for postdisaster intervention programs to reduce psychopathology. 相似文献