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991.
992.
Gamma-hydroxybutyric acid (GHB) is a drug with abuse potential, popularly known as "liquid ecstasy". It is an endogenous compound of the mammalian brain which satisfies many of the criteria for consideration as a neurotransmitter or neuromodulator. In this study, the effects of acute administration of GHB (40, 80 and 120 mg/kg, ip) on anxiety, tested in the light/dark box, were examined in male mice of the OF.1 strain. Likewise, we compared the behavioural profile of GHB with that induced by mCPP (1 mg/kg, ip), a compound with known anxiogenic actions. GHB-treated mice spent notably less time in the lit area (40 and 80 mg/kg) and more time in the dark area (all doses), whereas the total number of 'rearings', transitions and latency were significantly reduced. A very similar behavioural profile was observed in mCPP-treated animals. Overall, these findings indicate that GHB exhibits anxiogenic-like properties in male mice. It is suggested that the anxiogenic effects of GHB could be related to its ability to modulate GABA and/or dopaminergic receptors.  相似文献   
993.
Cognitive dysfunction has been widely studied in multiple sclerosis (MS), however decision-making has been less investigated. The current study examined the decision-making processes of patients with multiple sclerosis (MS) using a computerized version of the Iowa Gambling Task (IGT). This task was applied to 18 patients with clinically diagnosed MS and 18 healthy control subjects matched for age, sex, and years of education. The results showed that IGT scores differ significantly between patients with MS and the healthy control subjects: the patients with MS made significantly less advantageous decisions than the controls in the IGT. Possible causes of impaired decision-making in multiple sclerosis are discussed.  相似文献   
994.
It has been proposed that causal power (defined as the probability with which a candidate cause would produce an effect in the absence of any other background causes) can be intuitively computed from cause-effect covariation information. Estimation of power is assumed to require a special type of counterfactual probe question, worded to remove potential sources of ambiguity. The present study analyzes the adequacy of such questions to evoke normative causal power estimation. The authors report that judgments to counterfactual probes do not conform to causal power and that they strongly depend on both the probe question wording and the way that covariation information is presented. The data are parsimoniously accounted for by an alternative model of causal judgment, the Evidence Integration rule.  相似文献   
995.
According to the Perceptual Symbols Theory of cognition ( Barsalou, 1999 ), modality-specific simulations underlie the representation of concepts. A strong prediction of this view is that perceptual processing affects conceptual processing. In this study, participants performed a perceptual detection task and a conceptual property-verification task in alternation. Responses on the property-verification task were slower for those trials that were preceded by a perceptual trial in a different modality than for those that were preceded by a perceptual trial in the same modality. This finding of a modality-switch effect across perceptual processing and conceptual processing supports the hypothesis that perceptual and conceptual representations are partially based on the same systems.  相似文献   
996.
Since the 1950s, people with mental illness and their families have been organizing a wide range of self-directed, mutual support oriented initiatives, including self-help groups, nonprofit organizations, and businesses. These initiatives have become increasingly widespread over the years and today mental health self-help initiatives outnumber traditional mental health organizations in the United States (Goldstrom et al., Admin Policy Mental Health Mental Health Serv Res 33:92-103, 2006). Mental health self-help embodies much of what community psychologists promote, including the self-directed organization of people to create social change and facilitate personal transformation. This special issue provides new insight into several prominent areas of inquiry surrounding these low-cost interventions including: (1) their evidence base; (2) the processes by which people benefit; (3) how they interface with the mental health system; and (4) the value dilemmas they face.  相似文献   
997.
马克思主义中国化的出场路径——重读《实践论》   总被引:3,自引:0,他引:3  
重大历史时刻的高度重合往往映现着某种深刻的辩证结果.今年,<实践论>发表已逾70年,改革开放已历30周年.70年沧桑、30年辉煌,其中贯穿着一条主线:经过革命、建设、改革与发展历史的反复验证,马克思主义中国化的出场路径反复凸现:一切从实际出发是马克思主义中国化的现实出发点;从自主的实践出发科学地理解马克思主义文本的意义,促进两者的思想结合是后发展国家探索真理的基本道路;展开积极的思想对话、营造民主氛围是造就马克思主义理论创新、与时俱进的基本条件.  相似文献   
998.
2008年3月11日上午,中国无神论学会邀请部分在京专家和出版社编辑就组织翻译出版世界无神论著作的问题进行了座谈。 会议首先介绍了翻译世界无神论著作的学术背景和主要动因。认为:当前社会种种迹象表明,西方宗教渗透开始进入我国社会、经济、文化、教育等等领域,对我国的文化安全和意识形态构成威胁。尤其是大学里传教问题比较严重,  相似文献   
999.
The purpose of this article is to add to the discussion regarding identification of students with emotional and behavioral disorders (EBD). In addition, the article discusses services that students with EBD receive and their outcomes. The article reviews data from several national longitudinal studies to present a comprehensive picture of issues pertinent to this group of students. Unfortunately, outcomes for these students continue to be dismal. The article concludes with a discussion of areas for further consideration and attention.  相似文献   
1000.
A defining characteristic of age-related cognitive decline is a deficit in general cognitive performance. Here we use a testing and analysis regimen that allows us to characterize the general learning abilities of young (3-5 mo old) and aged (19-21 mo old) male and female Balb/C mice. Animals' performance was assessed on a battery of seven diverse learning tasks. Aged animals exhibited deficits in five of the seven tasks and ranked significantly lower than their young counterparts in general learning abilities (aggregate performance across the battery of tasks). Aging added variability to common core performance (i.e., general learning ability), which translated into increased variability on the individual cognitive tasks. Relatedly, general learning abilities did not differ between the two ages among the best quartile of learners (i.e., cognitive abilities were spared in a subsample of the aged animals). Additionally, working memory capacity (resistance to interference) and duration (resistance to decay) accounted for significantly more of the variability in general learning abilities in aged relative to young animals. Tests of 15 noncognitive performance variables indicated that an increase in body weight (and an associated decrease in general activity) was characteristic of those aged animals which exhibited deficient general learning abilities. These results suggest the possibility that general cognitive deficits in aged animals reflect a failure of specific components of the working memory system, and may be related to variations in body weight and an associated decrease in activity.  相似文献   
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