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71.
A meta-analysis of published studies with adult human participants was conducted to evaluate whether physical fitness attenuates cardiovascular reactivity and improves recovery from acute psychological stressors. Thirty-three studies met selection criteria; 18 were included in recovery analyses. Effect sizes and moderator influences were calculated by using meta-analysis software. A fixed effects model was fit initially; however, between-studies heterogeneity could not be explained even after inclusion of moderators. Therefore, to account for residual heterogeneity, a random effects model was estimated. Under this model, fit individuals showed significantly attenuated heart rate and systolic blood pressure reactivity and a trend toward attenuated diastolic blood pressure reactivity. Fit individuals also showed faster heart rate recovery, but there were no significant differences in systolic blood pressure or diastolic blood pressure recovery. No significant moderators emerged. Results have important implications for elucidating mechanisms underlying effects of fitness on cardiovascular disease and suggest that fitness may be an important confound in studies of stress reactivity.  相似文献   
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Book reviews     
TOATES, F. Animal Behaviour: A Systems Approach. Chichester: John Wiley and Sons. 1980. Pp. 299. Hardback £17. Paper back £6.40 ISBN 0 471 27724.

DICKINSON, A. Contemporary Animal Learning Theory. Cambridge: University Press. 1980. Pp. 177. Hardback £12.50. Paperback £3.95. ISBN 0 521 23469 7.  相似文献   
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Although a great deal of research has been conducted on the relationship between social support and physical health, the contribution of personality characteristics to this relationship has rarely been assessed. Structural equation modeling was employed to derive and test a model of the direct and indirect relationships between personality characteristics, social network size, the perceived availability of support, socially supportive behaviors, and perceived physical health with a sample of Pennsylvania adults. Significant paths indicate that individuals who perceive themselves as affiliative and as help seekers and help givers report larger social networks, receive more socially supportive behaviors, and perceive that more support is available to them. The perception that support is available shared a direct relationship with perceived physical health. The utility of including multiple measures of social support and personality characteristics related to receiving support in investigations of the relationship between social support and physical health is discussed.  相似文献   
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Suicides among older adults in the United States and Canada in the last decade have accounted for an increasing share of all suicides. In both countries the use of firearms among older adults has steadily increased. Despite these trends, little is known about the extent to which crisis centers are prepared to prevent elder suicide. A survey of AAS-listed crisis prevention centers examined the training, knowledge, and current practices relevant to elder suicide among personnel in 321 crisis prevention centers in both countries. Results revealed insufficient training, a lack of familiarity with recent suicide trends, and limited outreach to older adults.  相似文献   
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Cancellation tests are commonly used in the clinical assessment of visuospatial function, but there has been little study of task characteristics influencing performance. This study was designed to assess factors which affect cancellation performance. Sixteen healthy subjects sequentially performed four random-array letter cancellation tasks. The forms contained 50 and 100 stimuli and target:distractor (T/D) ratios of 1:4 and 1:9 with target letter “A” and randomly selected letter distractors. The primary performance measure was calculated as the number of correctly cancelled targets divided by the time to complete the task, corrected for accuracy. This measure revealed a strong effect of T/D ratio (p< .0001), with performance adversely affected by higher proportion of distractors. There was no effect of stimulus number. This suggests that T/D ratio should be considered in cancellation test design and interpretation.  相似文献   
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