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The purpose of this study was to determine the effects of Type A behavior and family history of hypertension on cardiovascular reactivity to mental stress in a group of employed black women. Measures of heart rate and of systolic blood pressure (SBP) and diastolic blood pressure (DBP) were taken at rest, during a mental arithmetic task, and during the Type A Structured Interview (SI). Results indicated that the Type A behavior pattern was associated with SBP and DBP hyperresponsivity during the SI but not during mental arithmetic. Additionally, certain speech components of the Type A pattern, as well as features of the potential-for-hostility component, were also related to cardiovascular responses during the SI. Family history of hypertension did not influence the cardiovascular parameters either alone or in combination with Type A behavior. The results suggest that many of the cardiovascular response characteristics of the Type A pattern that have been observed in predominantly white samples also hold true for blacks. Replication of these findings with other subgroups of blacks, such as young females and middle-aged males, will help document the generality of these findings within the black population.  相似文献   
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We examined the effects of acute psychological stress on lymphocyte proliferation and circulating levels of interleukin-1 and -2. Healthy men were exposed to two viewings of a gruesome surgery film and were asked to recall details of the film twice during a 30-min period. These subjects were compared to a nonstress control group. Lymphocyte proliferation to the mitogen concanavalin A (Con A; 5 micrograms/ml) was decreased during and after exposure to the stressor when compared to the control group. This decrease was more pronounced in subjects exhibiting greater blood pressure reactivity while viewing the film than in subjects showing smaller blood pressure responses. None of the other immunological measures was significantly affected by the stressor. Cortisol was not correlated with lymphocyte responsiveness. Possible explanations for these results and implications for further research are discussed.  相似文献   
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Wang  Jennifer 《Synthese》2018,198(8):1887-1898

Modal primitivists hold that some modal truths are primitively true. They thus seem to face a special epistemological problem: how can primitive modal truths be known? The epistemological objection has not been adequately developed in the literature. I undertake to develop the objection, and then to argue that the best formulation of the epistemological objection targets all realists about modality, rather than the primitivist alone. Furthermore, the moves available to reductionists in response to the objection are also available to primitivists. I conclude by suggesting that extant theories of the epistemology of modality are not sensitive to the question of primitivism versus reductionism.

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Ohne Zusammenfassung Mit 117 Abbildungen im Text.  相似文献   
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