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Most studies of suicide in younger patients have demonstrated significant alterations in the serotonin system. Although a high percentage of completed suicides occur in late-life, to date very few studies of the biology of suicide have focused on this age group. This chapter describes age-related changes in the central nervous system pertinent to the biology of suicide, then reviews post-mortem biological studies of the brains of suicides and suicide attempters. As suicide attempts in the elderly are characterized by the use of violent means, biologic studies of impulsive violence are discussed. Finally we describe data on the effect of degenerative diseases on the serotonin system and the possible link to increased suicidal behavior in affected patients. This review underscores the need for further study of the biology of suicide in the geriatric age group.  相似文献   
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A child's adjustment to wartime stress is reliant not only on individual responses and qualities, but very significantly on the availability of support that they may receive from their parent or caregivers and quality of relationships. Strengthening parental support has the potential to be valuable. A pilot two-arm randomised controlled trial investigated the feasibility of delivering and evaluating the “Caring for Children Through Conflict and Displacement” intervention with caregivers in the West Bank. Feasibility to recruit and train non-specialist staff on-the-ground to screen families for eligibility, collect outcome data, deliver the intervention and to recruit and retain families in the study were examined. Research staff and intervention facilitators were successfully appointed in the field, screened participants and delivered the intervention to 120 caregivers, collecting outcome measures pre-and post-delivery. All families completed the outcome measures, with very little missing data. This indicated that the intervention can be delivered feasibly and evaluated with families in this humanitarian context. Preliminary outcome data showed promise that the intervention may have the potential to both improve family functioning and reduce children's problem behaviour. Implications of family-focused initiatives, particularly within a conflict/post-conflict context for the prevention of several negative health and social outcomes directions, are discussed.  相似文献   
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Convergent and divergent stereo mechanisms were compared in their ability to recover structure from motion. Contrary to a recent result reported by Richards and Lieberman, no difference in their performance was found; both mechanisms appeared equally capable of supporting the perception of good structure from motion. Possible reasons for the disparate results are discussed.  相似文献   
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Two studies tested the hypothesis that certain positive emotions speed recovery from the cardiovascular sequelae of negative emotions. In Study 1, 60 subjects (Ss) viewed an initial fear-eliciting film, and were randomly assigned to view a secondary film that elicited: (a) contentment; (b) amusement; (c) neutrality; or (d) sadness. Compared to Ss who viewed the neutral and sad secondary films, those who viewed the positive films exhibited more rapid returns to pre-film levels of cardiovascular activation. In Study 2, 72 Ss viewed a film known to elicit sadness. Fifty Ss spontaneously smiled at least once while viewing this film. Compared to Ss who did not smile, those who smiled exhibited more rapid returns to pre-film levels of cardiovascular activation. We discuss these findings in terms of emotion theory and possible health-promoting functions of positive emotions.  相似文献   
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