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Cardiovascular reactivity to video game and mental arithmetic stressors was compared among three groups of men: aerobically trained mild hypertensives, untrained mild hypertensives, and a comparison group of untrained normotensives. Relative to the untrained hypertensives, the trained hypertensives reacted to the video game with marginally smaller systolic blood pressure and diastolic blood pressure, but there were no significant differences between these groups in reactivity during the mental arithmetic task. Comparisons between each hypertensive group and the normotensive group showed that blood pressure (BP) reactivity of normotensives during the video game was generally similar to that of trained hypertensives but smaller than that of untrained hypertensives. These results indicate that aerobic training, which has been found to reduce resting BP in mild hypertensives, may also exert a favorable impact in reducing cardiovascular reactivity of hypertensives during some stressful situations. 相似文献
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This study examines the effects of certain communication variables (member integration, boundary communication, environmental uncertainty, and system autonomy) on organizational effectiveness. While often discussed in the literature, these variables have not been precisely defined. As a result, a multiple indicator model using maximum likelihood estimates for each variable was created. Interviews with managers from 82 different organizations from a variety of industries are used to test the model. The results suggest that member integration and environmental uncertainty, when the latter is mediated by boundary communication, provide an excellent predictor of organizational effectiveness (R= .64). The results are discussed in light of the proposed theory along with implications for future research using intertypical sampling methods and LISREL analysis. 相似文献
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Cecil A. Rogers 《Behavior research methods》1968,1(2):51-54
Typical word-association procedures result in verbal response hierarchies for a specific stimulus word. The problem of assessing corresponding stimulus hierarchies is discussed Three approaches are entertained: obtaining associations to all of the words in the dictionary, clerical cross-indexing of existing response-hierarchy data, and obtaining backward associations which are then used in forward association. A comparison of data obtainable by the last two methods is presented. 相似文献
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