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961.
11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD-1) catalyses the interconversion of active cortisol and corticosterone with inert cortisone and 11-dehydrocorticosterone, thus regulating glucocorticoid access to intracellular receptors. In rats, chronic glucocorticoid excess or stress increases 11beta-HSD-1 in the hippocampus, producing suggestions that it may attenuate the deleterious effects of chronic glucocorticoid excess. However, 11beta-HSD-1 predominantly catalyses 11beta-reduction in the intact liver and hippocampal cells, thus regenerating active glucocorticoids from inert substrate. We studied 11beta-HSD activity in the tissues of male tree shrews following 28 days of sustained psychosocial stress or exogenous administration of cortisol. In the hippocampus, chronic psychosocial stress attenuated 11-HSD-1 activity (69 +/- 9% of control), whereas cortisol alone had no effect. In the liver, both chronic stress and cortisol administration decreased 11beta-HSD-1 activity (47 +/- 11% and 49 +/- 4% fall, resp.). Attenuation of 11beta-HSD-1 within tissues may reflect a homeostatic mechanism designed to minimise the adverse effects of prolonged stress and/or glucocorticoid excess.  相似文献   
962.
Clinical pragmatism: a method of moral problem solving   总被引:3,自引:0,他引:3  
This paper presents a method of moral problem solving in clinical practice that is inspired by the philosophy of John Dewey. This method, called "clinical pragmatism," integrates clinical and ethical decision making. Clinical pragmatism focuses on the interpersonal processes of assessment and consensus formation as well as the ethical analysis of relevant moral considerations. The steps in this method are delineated and then illustrated through a detailed case study. The implications of clinical pragmatism for the use of principles in moral problem solving are discussed.  相似文献   
963.
The background, rationale, methodology and outcomes of a project on developing local lifelong guidance strategies in four areas are outlined. The main components of the strategies developed in the four areas are analysed, and a number of issues relating to the process of strategy development are addressed. Much of the lack of coherence at local level stems from lack of coherence at national policy level: implications for national policy are examined. Finally, implications for parallel work in other localities are explored.  相似文献   
964.
We report the results of a prospective study of a random sample of 1353 elderly but healthy men and women who were followed up for a period of 10 yr, when mortality and cause of death were ascertained. Overall results have been reported elsewhere for mortality from cancer, coronary heart disease and other causes; here we are concerned with the personality factors predicting breast cancer, cervical cancer, cancer of the corpus uteri specifically, as well as other types of cancer in women. Ten specific hypotheses were tested, using specially constructed questionnaires for the purpose, and for most of these statistically significant support was obtained. The results justify belief that specific types of cancer may be related to specific stress/personality factors.  相似文献   
965.
966.
Landolt  Monica A.  Dutton  Donald G. 《Sex roles》1997,37(5-6):335-359
A study was conducted to investigate the issue of gay male intimate abuse in a sample of 52 couples. The objective of the study was to explore the association between relationship power dynamics and the perpetration of psychological abuse, and to investigate the correspondence between intimate abuse and factors associated with the Abusive Personality [D. G. Dutton and A. J. Starzomski (1993) Borderline Personality in Perpetrators of Psychological and Physical Abuse, Violence and Victims, Vol. 8, pp. 327–337; D. G. Dutton (1994a) Behavioral and Affective Correlates of Borderline Personality Organization in Wife Assaulters, International Journal of Law and Psychiatry, Vol. 17, pp. 265–279.] The majority of participants were middle to upper class and their ethnic/racial breakdown is as follows: White (86%), Native American (7%), Asian (4%), and Other (3%). In terms of power, results indicated that the more frequent form of psychological abuse was significantly higher in relationships characterized by divided power (i.e., partners sharing decision-making authority by the partners each making decisions in different domains). This finding supports the supposition that abuse can occur in relatively egalitarian relationships. An association between intimate abuse and the Abusive Personality was also clearly observed and this personality profile seemed to characterize both members of abusive dyads. Conclusions are drawn regarding the generalizability of intimate abuse across lines of sexual orientation.  相似文献   
967.
The psychophysiological approach was used to evaluate the effects of feature similarity and intrinsic response mapping on the flanker compatibility effect. Symbol (e.g., < > < and < / <) and letter arrays (e.g., HCH and SCS) were used. Results showed that delays in stimulus evaluation and both peripheral and central response competition contributed to the compatibility effect, with the contribution of these processes depending on feature similarity and the intrinsic response mapping of the stimuli. For letter stimuli, the difference in the size of the compatibility effect for similar and dissimilar arrays could be accounted for in terms of stimulus evaluation. For symbol arrays, differences in size of the compatibility effect could be accounted for by response competition. Thus, symbol and letter arrays do not appear to be processed differently; what is different is the degree to which stimulus and response-related processes are affected by incompatibility.  相似文献   
968.
The relationship of locus of control to depression, anxiety, hostility, and physical health was assessed in a sample of multicultural college students (N = 162). Powerful Others Health Locus of Control was correlated with depression, anxiety, hostility, and recent physical symptoms while Chance Health Locus of Control (CHLC) was correlated with all of the above as well as chronic physical symptoms and major health problems. When controlling for a variety of health risk factors (viz., age, sex, body mass, exercise, smoking, salt, alcohol, and caffeine), only CHLC remained significant in the physical health models. Results support the cognitive model of mental health which emphasize the importance of adaptive beliefs. Specifically, they suggest that issues about control are related to negative affect and indicate that the often-cited relationship of an external locus of control to depression and anxiety also holds for hostility. The findings do not, however, support the view that anxiety and depression are associated with different types of external locus of control but rather suggest a unified set of locus of control beliefs underlying the three types of negative affect. In addition, evidence is provided for the external validity of the Multidimensional Health Locus of Control (MHLC) Scales with respect to mental health. Further, the results indicate that belief about one’s health may play a significant role in one’s physical health and that the health behavior model of the relationship between locus of control and physical health is insufficient to explain the relationship. As the Chance and Powerful Others MHLC scales were not related to health habits in this sample but were related to mental health (viz., depression, anxiety, and hostility), locus of control beliefs may be related to physical health via their relationship with mental health.  相似文献   
969.
Sexuality education for children and young adults is one of the most heavily debated issues facing policy-makers, national AIDS program planners, and educators, provoking arguments over how explicit education materials should be, how much of it there should be, how often it should be given, and at what age instruction should commence. In this context, the World Health Organization's Global Program on AIDS' Office of Intervention Development and Support commissioned a comprehensive literature review to assess the effects of HIV/AIDS and sexuality education upon young people's sexual behavior. 52 reports culled from a search of 12 literature databases were reviewed. The main purpose of the review is to inform policy-makers, program planners, and educators about the impact of HIV and/or sexuality education upon the sexual behavior of youth as described in the published literature. Of 47 studies which evaluated interventions, 25 reported that HIV/AIDS and sexuality education neither increased nor decreased sexual activity and attendant rates of pregnancy and sexually transmitted diseases (STDs). 17 reported that HIV and/or sexuality education delayed the onset of sexual activity, reduced the number of sex partners, or reduced unplanned pregnancy and STD rates Only 3 studies found increases in sexual behavior associated with sexuality education. Inadequacies in study design, analytic techniques, outcome indicators, and the reporting of statistics are discussed.  相似文献   
970.
present research examined the role of hippocampal NMDA-dependent synaptic potentiation on appetitive instrumental conditioning under a continuous reinforcement schedule. In the first experiment, low (.025 mg.kg) or moderate (.05 mg/kg) dosages of the NMDA receptor antagonist, MK801, failed to increase the number of training days required to reach acquisition criterion; number of training days required to reach criterion for extinction were also unaffected. In the second experiment, a higher dosage (.10 mg/kg) of MK801 or induction of long-term potentiation failed to alter the number of responses occurring during acquisition. These data suggest that hippocampal synaptic potentiation does not play a prominent role in instrumental learning with simple contingency conditions. It is suggested that hippocampal LTP reflects a perceptual process that contributes differentially to spatial cognition, classical and instrumental conditioning.  相似文献   
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