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191.
With the expansion of genetic services to various cultural groups, genetic counselors encounter clients who hold diverse beliefs inscribed by their culture about health conditions. Thus, clients may attribute the cause of a birth defect or genetic condition to a culturally-based health belief. This present study was conducted as a pilot study in order to assess the beliefs about the causes of birth defects and genetic disorders held by women of different ethnocultural backgrounds. This study proposed that women who do not have a family history of a disorder will differ in their knowledge about the cause of a birth defect or genetic disorder compared to women who have an affected child. In addition, this study determined to what extent culturally-based health beliefs are attributed to being the cause of a birth defect or genetic disorder in the 1990s. 相似文献
192.
Abrams TW Yovell Y Onyike CU Cohen JE Jarrard HE 《Learning & memory (Cold Spring Harbor, N.Y.)》1998,4(6):496-509
An important recent insight in a number of neurobiological systems is that during learning, individual dually regulated proteins with associative properties function as critical sites of stimulus convergence. During conditioning in Aplysia, the Ca2+ /calmodulin-sensitive adenylyl cyclase (AC) in mechanosensory neurons serves as a molecular site of interaction between Ca2+ and serotonin [5-hydroxytryptamine (5-HT)]-two signals that represent the CS and US in these cells. Conditioning requires that the CS and US be paired within a narrow time window and in the appropriate sequence. AC shows an analogous sequence preference: It is more effectively activated when a pulse of Ca2+ precedes a pulse of 5-HT than when the 5-HT precedes Ca2+. One mechanism that contributes to this sequence preference is that Ca2+/calmodulin binding to AC accelerates the rate of AC activation by receptor-Gs. We have identified two additional properties of AC activation that would cause pairing with Ca2+ preceding 5-HT to be more effective than simultaneous pairing or pairing with the reciprocal sequence: (1) Activation of Aplysia AC by a Ca2+ pulse rose with a delay compared with activation by a 5-HT pulse. (2) A late pulse of Ca2+, which arrived after 5-HT, acted, via calmodulin, to accelerate the decay of AC activation by receptor-Gs. Together, these activation properties of AC may contribute to the CS-US sequence requirement of classical conditioning. 相似文献
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Lesley Cohen 《Synthese》1986,67(1):51-55
While Curley argues that we need to know the history of philosophy so as not to avoid important alternatives to contemporary proposals, I argue that philosophy is an essentially historical enterprise. Unlike science, philosophy cannot forget its history. Not to know the history of philosophy is not to understand why the questions we seek to answer are worth answering or asking. 相似文献
195.
Referent communication disturbances in acute schizophrenia 总被引:1,自引:0,他引:1
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D B Cohen 《Journal of personality and social psychology》1975,32(6):1090-1093
Male subjects scoring high (n=17) or low (n=14) on the Maudsley Neuroticism scale were randomly assigned to a positive (n=17) or negative (ego threat) (n=14) presleep condition and then slept a single night in the laboratory. The negative condition elicited significantly more rapid eye movement activity (REM density) than did the positive condition (pless than.03). There was a significant interaction for Groups X Conditions (pless than.007) indicating that low neuroticism subjects had greater REM density in the negative condition, and less REM density in the positive condition, compared to high neuroticism subjects under either condition. The low neuroticism subjects in the negative condition showed a discrepancy between greater REM density but less admission of stress on a presleep mood questionnaire compared to high neuroticism subjects. These results support the hypothesis that REM density is a correlate of stress-induced arousal that is subject to the modifying effects of individual differences. 相似文献
198.
Cohen SL 《Journal of the experimental analysis of behavior》1975,24(3):333-341
Responses on one key (the main key) of a two-key chamber produced food according to a second-order variable-interval schedule with fixed-interval schedule components. A response on a second key (the changeover key) alternated colors on the main key and provided a second independent second-order variable-interval schedule with fixed-interval components. The fixed-interval component on one variable-interval schedule was held constant at 8 sec, while the fixed interval on the other variable-interval schedule was varied from 0 to 32 sec. Under some conditions, a brief stimulus terminated each fixed interval and generated fixed-interval patterns; in other conditions, the brief stimulus was omitted. Relative response rate and relative time deviated substantially from scheduled relative reinforcement rate and, to a lesser extent, from obtained relative reinforcement rate under both brief-stimulus and no-stimulus conditions. Matching was observed with equal components on both schedules; with unequal components, increasingly greater proportions of time and responses than the matching relation would predict were spent on the variable-interval schedule containing the shorter component. Preference for the shorter fixed interval was typically more extreme under brief-stimulus than under no-stimulus schedules. The results limit the extension of the matching relation typically observed under simple concurrent variable-interval schedules to concurrent second-order variable-interval schedules. 相似文献
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