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101.
While many studies have attempted to produce hypertension through the use of various environmental Stressors, few have succeeded in producing chronic elevations in blood pressure beyond levels considered to be borderline hypertensive (140–160 mm Hg systolic). The problem with most studies stems from the use of genetically normotensive animals and the selection of Stressors to which animals readily adapt. A new approach is suggested, which recognizes the role of genetics in human essential hypertension. Animals with one hypertensive parent do not develop spontaneous hypertension but show a more sensitive cardiovascular response to environmental Stressors than animals with normotensive parents. Preliminary studies revealed that animals with a mixed genetic history of hypertension develop spontaneous borderline hypertension. When subjected to shock-shock conflict, these borderline hypertensive rats (BHR) developed permanent hypertension that failed to abate even after a ten-week, shock-free recovery period. The hypertension was accompanied by elevated heart weight to body weight ratios and by significant cardiac pathology. Subsequent work has demonstrated that these animals also become hypertensive when fed a high-sodium diet. Finally, in a series of exercise studies, we found that BHRs subjected to a shock stressor were protected against stress-induced hypertension if they exercised daily. The potential of this model for studies of the mechanisms by which environmental variables produce permanent hypertension is discussed. 相似文献
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E. James Kehoe Constantine X. Poulos I. Gormezano 《Integrative psychological & behavioral science》1985,20(1):29-38
Two experiments examined appetitive differential conditioning of the rabbit’s jaw movement response (JMR) in a two-phase procedure. The first phase entailed reinforced training with one conditioned stimulus (CS+), and the second phase involved intermixed presentations of CS+ and an unreinforced stimulus (CS?). In Experiment 1, CS+ was a 600-Hz tone, and CS-was either a 660-,1,000-, or 2,100-Hz tone. In Experiment 2, the magnitude of the water unconditioned stimulus (US) paired with CS+ was either 1, 3, or 9 ml. The experiments revealed that 1) the level of responding to CS-rose for several days and then declined over the remainder of training; 2) the physical similarity between CS+ and CS?directly affected the level of responding to CS?but had no discernable effect on the level of responding to CS+ ; and 3) US magnitude positively affected the level of responding to CS + and, to a lesser extent, CS?. The results are discussed in terms of their implications for Spence’s gradient interaction theory and Pavlov’s external inhibition hypothesis. 相似文献
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Bernstein DM Santelli J Alter-Reid K Androsiglio V 《Journal of personality assessment》1985,49(3):273-281
Although the concept of interpersonal pursuing and distancing has been introduced and used clinically, the lack of a reliable and valid measure has deterred its more formal investigation and relevance to personality theory. The Pursuing-Distancing (P-D) Scale, a 92-item measure of the behavioral expression of these characteristics, was developed. Evidence for internal consistency as well as internal support of construct validity is presented and discussed. An 80-item revised scale is available from the authors and is currently being evaluated in a variety of external validation settings. 相似文献
107.
This study empirically tested Bem's (1974) assumption that the BSRI Masculinity and Femininity scales measure sex-typed standards of desirable behavior for men and women in American society. The adequacy of items in the two scales was evaluated by Bem's (1974) criteria using two types of desirability and stereotype ratings. Results obtained in all the experimental conditions except one involving Bem's desirability instructions and Bem's rating scale did not support the tested assumption. Implications of these results for revising the BSRI scales were discussed. 相似文献
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