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601.
以门阀士族为其统治基础的西晋王朝,在确保士族权益的同时,皇族司马氏也需要一批事功派官僚以限制士族势力的过分膨胀,从而维持其君主的专制权威.然而,晋武帝却始终没有重用事功派官僚刘毅,作者认为,其主要原因是刘毅始终忠于曹魏,一直对司马氏的统治持敌视态度.而晋武帝"容忍"刘毅的主要原因则是当时亲曹力量依然十分庞大. 相似文献
602.
Histone modifications around individual BDNF gene promoters in prefrontal cortex are associated with extinction of conditioned fear 总被引:3,自引:0,他引:3
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Bredy TW Wu H Crego C Zellhoefer J Sun YE Barad M 《Learning & memory (Cold Spring Harbor, N.Y.)》2007,14(4):268-276
Extinction of conditioned fear is an important model both of inhibitory learning and of behavior therapy for human anxiety disorders. Like other forms of learning, extinction learning is long-lasting and depends on regulated gene expression. Epigenetic mechanisms make an important contribution to persistent changes in gene expression; therefore, in these studies, we have investigated whether epigenetic regulation of gene expression contributes to fear extinction. Since brain-derived neurotrophic factor (BDNF) is crucial for synaptic plasticity and for the maintenance of long-term memory, we examined histone modifications around two BDNF gene promoters after extinction of cued fear, as potential targets of learning-induced epigenetic regulation of gene expression. Valproic acid (VPA), used for some time as an anticonvulsant and a mood stabilizer, modulates the expression of BDNF, and is a histone deacetylase (HDAC) inhibitor. Here, we report that extinction of conditioned fear is accompanied by a significant increase in histone H4 acetylation around the BDNF P4 gene promoter and increases in BDNF exon I and IV mRNA expression in prefrontal cortex, that VPA enhances long-term memory for extinction because of its HDAC inhibitor effects, and that VPA potentiates the effect of weak extinction training on histone H4 acetylation around both the BDNF P1 and P4 gene promoters and on BDNF exon IV mRNA expression. These results suggest a relationship between histone H4 modification, epigenetic regulation of BDNF gene expression, and long-term memory for extinction of conditioned fear. In addition, they suggest that HDAC inhibitors may become a useful pharmacological adjunct to psychotherapy for human anxiety disorders. 相似文献
603.
It recently has been established within the laboratory that the attentional probe methodology not only can sensitively assess the threat attentional bias associated with anxiety vulnerability, but also can be configured to yield training tasks capable of modifying emotional vulnerability by manipulating such attentional selectivity. In order to appraise and exploit the potential practical applications of such procedures, it is desirable that clinical investigators without specialist equipment should become able to deliver such tasks within field settings. The present research program involved development of a fully customizable attentional probe software package, that delivers assessment and training versions of the probe task across the Internet. Two experimental studies served to validate the assessment and training efficacy of resulting probe task variants, completed remotely by GAD sufferers and nonclinical populations using their own computers. We advise fellow researchers how to freely download this software package for use within their own investigations. 相似文献
604.
中国心理健康服务从业者的职业压力现状及影响因素 总被引:4,自引:0,他引:4
本研究目的是考察心理健康从业者的压力现状及其影响因素。769名来自全国20个省份的心理健康从业者填写了研究者自编的有93个多项选择题和填空题的问卷,其中2个从本问卷中抽取的5点量表具有可接受的心理测量学指标。主因素分析表明,心理健康从业者的职业压力可分为三类:专业能力不足、缺乏单位支持、工作负担过重。回归分析表明:影响职业压力的非专业因素有:年龄,性别,教育水平,全职或兼职,场所是否专用,以及每周咨询的小时数。在专业因素中,督导和培训能显著地缓解心理健康从业者的职业压力。治疗中的困难情况会显著地引发心理健康从业者的职业压力。 相似文献
605.
606.
运用多元概化理论及其方法,本研究分析了上海市高考历史试卷(2006年),结果发现:(1)在试卷结构,各部分试题具有较好的测量信度,但在赋分比例存在问题;(2)在主观题评分,评阅者对分数影响微弱,说明分数能较为真实地反映不同考生之间的学科知识和能力差异。此外,研究还为将来提高高考命题和评阅质量提供合理化建议。 相似文献
607.
Clinical observations suggest that re-experiencing symptoms are triggered by stimuli that are perceptually similar to those present shortly before the trauma or its worst moments. Two experiments investigated the possible role of perceptual priming in this phenomenon. Volunteers (N = 28, N = 62) watched a series of "traumatic" and neutral picture stories, and completed blurred object identification (priming) and recognition memory tasks. Neutral objects that immediately preceded the "traumatic" stories were more strongly primed, but not better recognised, than objects from neutral stories. Enhanced priming predicted subsequent re-experiencing symptoms. The results support the role of perceptual priming in re-experiencing. 相似文献
608.
Cross-society comparisons have become increasingly important to the study of the perceived quality of life. A major critique of these studies, however, is the lack of attention to intra-culture variation. This paper examines how subjective quality of life differs, at both societal and individual levels, between Taiwan and Hong Kong, two Chinese societies that share their cultural heritage but vary in their social and political systems. We draw upon data from synchronic surveys conducted in November 2000 in Taiwan (n=1222) and Hong Kong (n=1044). Ordinal regression analyses confirm that, for both societies, reported satisfaction at the societal level contributes to the variance in individuals quality of life. Moreover, the perceived fairness with regard to personal effort within the opportunity structure provided by the society also significantly affects an individuals quality of life. Different factors accounting for quality of life variation in Taiwan and in Hong Kong are discussed. This paper suggests that for the intra-cultural, cross-society comparisons on quality of life, inclusion of various societal level indicators is not only important, but the subjective perception of the fairness that society also contributes a significant effect. 相似文献
609.
Dhar and Gorlin (2013) proposed a dual-process perspective on choice. We applaud the effort to generate such a model, and we support the effort to integrate potentially disparate literatures under a general theoretical approach. In an attempt to further that goal of integration, we discuss similarities and differences between the proposed approach and the Elaboration Likelihood Model (Petty, 1977, Petty and Cacioppo, 1979, Petty and Cacioppo, 1986) — one of the earliest models of evaluative judgment to propose different mechanisms and consequences of judgments formulated at different levels of motivation and ability to process available information. In addition, because many choice settings involve familiar options that have been previously evaluated, we discuss potential implications of the literature on influences of attitudes on behavior (which can often be framed as involving a choice to act or not or to act in one way rather than another). In each case, we believe that these previous social psychological literatures provide insights that could enhance and extend the proposed model. 相似文献
610.
Map reading is unique to humans but is present in people of diverse cultures, at ages as young as 4 years old. Here, we explore the nature and sources of this ability and ask both what geometric information young children use in maps and what nonsymbolic systems are associated with their map-reading performance. Four-year-old children were given two tests of map-based navigation (placing an object within a small three-dimensional [3D] surface layout at a position indicated on a two-dimensional [2D] map), one focused on distance relations and the other on angle relations. Children also were given two nonsymbolic tasks, testing their use of geometry for navigation (a reorientation task) and for visual form analysis (a deviant-detection task). Although children successfully performed both map tasks, their performance on the two map tasks was uncorrelated, providing evidence for distinct abilities to represent distance and angle on 2D maps of 3D surface layouts. In contrast, performance on each map task was associated with performance on one of the two nonsymbolic tasks: Map-based navigation by distance correlated with sensitivity to the shape of the environment in the reorientation task, whereas map-based navigation by angle correlated with sensitivity to the shapes of 2D forms and patterns in the deviant-detection task. These findings suggest links between one uniquely human, emerging symbolic ability, geometric map use, and two core systems of geometry. 相似文献