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排序方式: 共有898条查询结果,搜索用时 31 毫秒
21.
大多数人在其一生中都会经历创伤事件,但只有少数人会发展成为创伤后应激障碍(PTSD)。焦虑障碍的易感性和保护因素成为一个重要议题。基于恐惧记忆习得与消退模型的研究发现女性个体表现出“易习得、难消退”的特点。在恐惧相关脑区的脑生理结构、功能/结构连接性、以及大脑可塑性的性别差异可能是该特征的根本原因。性激素作为一种焦虑障碍的保护因素,可以调节这种性别差异,这种调节效应可能是通过影响大脑结构形态(如神经细胞的形态和数量)、调控与记忆相关基因的表达(如HDAC4)而实现的。雌性激素水平的不稳定性可能是女性易感焦虑障碍的重要原因。未来对性别差异的深入研究将有助于推进个性化医疗。 相似文献
22.
采用元分析方法探讨人口统计学特征与公共服务动机之间的关系。经筛选, 共纳入138篇492个独立样本(N = 1078442)。结果发现, 性别、年龄、教育程度、组织任期、工作任期、职位等级和收入与公共服务动机之间均呈显著的正相关关系, 且与公共服务动机不同维度之间的关系均存在差异, 婚姻状况与公共服务动机间不存在显著的相关关系。此外, 公共服务动机测量工具、测量时间点和文化背景对部分人口统计学特征与公共服务动机之间的关系有调节作用。研究结果为人口统计学特征如何影响公共服务动机提供了较为精确的估计, 对于发展公共服务动机理论, 激励员工工作积极性, 提高公共部门服务水平都有重要意义。 相似文献
23.
24.
本研究使用单次匿名最后通牒博弈任务,采用2(性别: 男性, 女性)×3(社会距离: 自我决策, 替朋友决策, 替他人决策)×5(提议类型: 1/9, 2/8, 3/7, 4/6, 5/5)的混合实验设计,通过操作反应者的不同社会距离,考察资产分配情境下自我-他人决策的性别差异。研究结果发现:(1)相比于自我决策和替朋友决策,女性被试替他人决策时更愿意接受提议1/9,2/8和3/7,而提议4/6和5/5的接受率不受社会距离的影响;男性被试中社会距离和提议类型的交互作用不显著;(2)不平等提议的反应时随社会距离增加而逐渐降低,而平等提议的反应时不受社会距离的调节;(3)替他人决策时女性的接受阈限显著低于男性,而自我决策及替朋友决策时接受阈限不存在性别差异。 相似文献
25.
LaFleur WR 《Zygon》2002,37(3):623-642
This essay argues that Japan's resistance to the practice of transplanting organs from persons deemed "brain dead" may not be the result, as some claim, of that society's religions being not yet sufficiently expressive of love and altruism. The violence to the body necessary for the excision of transplantable organs seems to have been made acceptable to American Christians at a unique historical "window of opportunity" for acceptance of that new form of medical technology. Traditional reserve about corpse mutilation had weakened and, especially as presented by the theologian Joseph Fletcher, organ donation was touted as both expressive of agape and a way of "updating" Christianity via the ethics of Utilitarianism. Many Japanese, largely Buddhist and Confucian in their orientation, view these changed valorizations as neither necessary nor patently more ethical than those of their own traditions. 相似文献
26.
Chapman E 《Journal of genetic counseling》2002,11(5):351-367
This paper examines some of the ethical dilemmas that arise when testing for the late onset, untreatable condition of Huntington disease (HD) specifically now that technology allows us to test younger generations of the family for the mutant gene. Drawing on interview data from families with Huntington disease, the reactions to testing and perceived impact on other family members are considered. These are discussed in the light of the possible lowering of the age of test applicants. This potentially raises problems for a younger generation as they are confronted with reproductive decisions that the older generation did not have to face. It also means that individuals have the prospect of living with knowledge of a future illness for much longer. 相似文献
27.
An age-related decline in memory has been reported in male rats; however, there are few studies that have addressed these changes in aged female rats. In young female rats, hormonal cycles influence behavior. By the age of 22 months most female rats have not had regular hormonal cycles for at least 9 months. In the current study we examined how the hormonal status (persistent estrus and pseudo-pregnant) of the aged (22-24 months) female rat (Long Evans) influenced performance on a spatial version of the Morris water maze and compared this to aged male rats. Aged females in persistent estrus showed better performance on the water maze than both aged females that were pseudopregnant and aged males. Thus, postestropausal hormonal status may influence the course of aging in females. 相似文献
28.
Simultaneous visual discrimination in Asian elephants 总被引:3,自引:0,他引:3
Nissani M Hoefler-Nissani D Lay UT Htun UW 《Journal of the experimental analysis of behavior》2005,83(1):15-29
Two experiments explored the behavior of 20 Asian elephants (Elephas aximus) in simultaneous visual discrimination tasks. In Experiment 1, 7 Burmese logging elephants acquired a white+/black- discrimination, reaching criterion in a mean of 2.6 sessions and 117 discrete trials, whereas 4 elephants acquired a black+/white- discrimination in 5.3 sessions and 293 trials. One elephant failed to reach criterion in the white+/black- task in 9 sessions and 549 trials, and 2 elephants failed to reach criterion in the black+/white- task in 9 sessions and 452 trials. In Experiment 2, 3 elephants learned a large/small transposition problem, reaching criterion within a mean of 1.7 sessions and 58 trials. Four elephants failed to reach criterion in 4.8 sessions and 193 trials. Data from both the black/white and large/small discriminations showed a surprising age effect, suggesting that elephants beyond the age of 20 to 30 years either may be unable to acquire these visual discriminations or may require an inordinate number of trials to do so. Overall, our results cannot be readily reconciled with the widespread view that elephants possess exceptional intelligence. 相似文献
29.
Selective age-related differences in source memory relative to item memory, and individual differences in memory performance in relation to anxiety were explored with high- and low-anxious subjects screened from normal young and elderly adults. They were read false facts about the locations of well-known and unknown sights in a male or female voice. Intentional and incidental learning instructions were administered for source memory. Selective age-related deficits in source memory were observed under both encoding conditions. Higher level of anxiety was related to lower memory performance only in the old group; this relation was stronger in source recall. The findings suggest that the presence of such selectivity is unrelated to the tradeoff between item encoding and source encoding. Anxiety affects the variability, and mediates the selectivity of age effects on episodic memory. 相似文献
30.
Domestic chicks are capable of perceiving as a whole objects partly concealed by occluders (amodal completion). In previous studies chicks were imprinted on a certain configuration and at test they were required to choose between two alternative versions of it. Using the same paradigm we now investigated the presence of hemispheric differences in amodal completion by testing newborn chicks with one eye temporarily patched. Separate groups of newly hatched chicks were imprinted binocularly: (1) on a square partly occluded by a superimposed bar, (2) on a whole or (3) on an amputated version of the square. At test, in monocular conditions, each chick was presented with a free choice between a complete and an amputated square. In the crucial condition 1, chicks tested with only their left eye in use chose the complete square (like binocular chicks would do); right-eyed chicks, in contrast, tended to choose the amputated square. Similar results were obtained in another group of chicks imprinted binocularly onto a cross (either occluded or amputated in its central part) and required to choose between a complete or an amputated cross. Left-eyed and binocular chicks chose the complete cross, whereas right-eyed chicks did not choose the amputated cross significantly more often. These findings suggest that neural structures fed by the left eye (mainly located in the right hemisphere) are, in the chick, more inclined to a global analysis of visual scenes, whereas those fed by the right eye seem to be more inclined to a featural analysis of visual scenes. 相似文献