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61.
Studies of psychosocial influences on coronary artery atherogenesis in cynomolgus monkeys 总被引:1,自引:0,他引:1
The cynomolgus macaque provides a suitable primate model for studying how psychosocial factors contribute to coronary artery atherogenesis. Important interactions with diet, sex, and behaviorally elicited cardiovascular reactivity are described. 相似文献
62.
S R Hursh T G Raslear D Shurtleff R Bauman L Simmons 《Journal of the experimental analysis of behavior》1988,50(3):419-440
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
63.
Two experiments investigated the effects of successive reinforcement contexts on choice. In the first, concurrent variable-interval schedules of primary reinforcement operated during the initial links of concurrent chains. The rate of this reinforcement arranged by the concurrent schedules was decreased across conditions: When it was higher than the terminal-link rate, preference for the higher frequency initial-link schedule increased relative to baseline. (During baseline, a standard concurrent-schedule procedure was in effect). When the initial-link reinforcement rate was lower than the terminal-link rate, preference converged toward indifference. In the second experiment, a chain schedule was available on a third key while a concurrent schedule was in effect on the side keys. When the terminal link of the chain schedule was produced, the side keys became inoperative. Availability of the chain schedule did not affect choice between the concurrent schedules. These results show that only when successive reinforcement contexts are produced by choice responding do those successive contexts affect choice in concurrent schedules. 相似文献
64.
Jeffrey S. Levin Ph.D. M.P.H. C. David Jenkins Ph.D. Robert M. Rose M. D. 《Journal of religion and health》1988,27(4):267-278
In a study of air traffic controllers, religious differences are found in the way Type A behavior is associated with several health status indicators. Associations between the Jenkins Activity Survey (JAS) and physical illness incidence, health-promotive behavior, diastolic and systolic blood pressure, subjective distress and impulse control problems, and alcohol consumption are examined by religious attendance, religious affiliation, and change in affiliation. Findings confirm that Type A does not vary significantly by religion. However, there are several significant findings between Type A and various health indicators. Type A is associated with illness incidence, overall and more strongly in several religion, subgroups. Type A and alcohol consumption are related positively in Protestants and converts, and negatively in churchgoing Catholics. Type A is related to impulse control problems in churchgoing Protestants and to subjective distress in churchgoing Catholics. Finally, in individuals with weak or no religious ties, Type A is associated with lower blood pressure. This last finding suggests that in some people (for example, the irreligious or unchurched), the coronary-prone behavior pattern may have cardiovascular effects which are salutary in at least one respect.The authors wish to thank Dr. Kyriakos S. Markides and Laura A. Ray for their assistance with this study. Address requests for reprints to Dr. Levin at the Institute of Gerontology, 300 North Ingalls, Ann Arbor, MI 48109. 相似文献
65.
66.
B A Maher T C Manschreck C C Weisstein M L Schneyer R Okunieff 《Perceptual and motor skills》1988,67(3):911-918
This report examines two methodologic concerns pertaining to use of the cloze procedure in studying the predictability of schizophrenic speech, scoring criteria and raters' education (at or below college level). We find that two strategies for scoring the predictions of raters, one requiring the exact word, the other permitting a reasonable synonym, do not appear to differ in distinguishing groups of patients. The accuracy of raters' guessing is, however, correlated with raters' education: the more educated the rater, the more accurate the guessing. Thought-disordered schizophrenic speech is significantly less predictable than that of nonthought-disordered schizophrenics and normal controls when scored by less educated raters. These differences diminish when more highly educated raters are used. We conclude that raters' education can influence the sensitivity of cloze analysis. 相似文献
67.
Individuals with stronger sex-role identities may be expected to show greater conformity to sex-typed behaviors. Proceeding from this assumption, the sex-role status and sex of students using different styles of carrying books were compared. This study also examined whether over-all hand preference or age were related to carrying styles or sex-role status. Subjects completed a questionnaire comprised of the 24-item Personal Attributes Questionnaire of Spence and Helmreich, a 6-item scale of hand preference and a self-rating of sex-role identity. Afterwards, each subject's carrying style was covertly observed and recorded. Most subjects carried their materials in a sex-typical way or in book bags (for which no sex-typed carrying styles were discovered). As in previous studies, men in this study scored higher than women on masculinity and androgyny and lower on femininity. Hand preference was not related to sex-role status. Carrying style was not significantly correlated with any of the predictor variables for men, perhaps because almost no variance in carrying style was observed among them. Women who used masculine carrying styles tended to be older, have greater instrumentality, and a more masculine identity. 相似文献
68.
Jeffrey C. King 《Philosophical Studies》1988,53(3):417-440
I have benefited greatly from discussing the issues addressed in this paper with Michael Liston, John Vickers and Mark Wilson. 相似文献
69.
E Schier T Yecunnoamlack T Tegegne 《Psychiatrie, Neurologie, und medizinische Psychologie》1988,40(8):490-499
Of 1240 first-time consultations in the neuropsychiatric clinic of the Gondar College of Medical Sciences in an eleven-month period during 1985 and 1986, 152 patients came seeking relief from seizures. This paper deals with the origins and background of diagnostic, differential diagnostic, and therapeutic problems, and with problems of social rehabilitation. While in such a tradition-bound society certain hypotheses continue to have an unfavorable effect, there are unmistakable signs of positive change against a background of rapid social change. Conclusions are drawn for the better management of epileptic patients in developing countries. 相似文献
70.