首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 25 毫秒
1.
Kv4 channels regulate the backpropagation of action potentials (b-AP) and have been implicated in the modulation of long-term potentiation (LTP). Here we showed that blockade of Kv4 channels by the scorpion toxin AmmTX3 impaired reference memory in a radial maze task. In vivo, AmmTX3 intracerebroventricular (i.c.v.) infusion increased and stabilized the EPSP-spike (E-S) component of LTP in the dentate gyrus (DG), with no effect on basal transmission or short-term plasticity. This increase in E-S potentiation duration could result from the combination of an increase in excitability of DG granular cells with a reduction of GABAergic inhibition, leading to a strong reduction of input specificity. Radioactive in situ hybridization (ISH) was used to evaluate the amounts of Kv4.2 and Kv4.3 mRNA in brain structures at different stages of a spatial learning task in naive, pseudoconditioned, and conditioned rats. Significant differences in Kv4.2 and Kv4.3 mRNA levels were observed between conditioned and pseudoconditioned rats. Kv4.2 and Kv4.3 mRNA levels were transiently up-regulated in the striatum, nucleus accumbens, retrosplenial, and cingulate cortices during early stages of learning, suggesting an involvement in the switch from egocentric to allocentric strategies. Spatial learning performance was positively correlated with the levels of Kv4.2 and Kv4.3 mRNAs in several of these brain structures. Altogether our findings suggest that Kv4 channels could increase the signal-to-noise ratio during information acquisition, thereby allowing a better encoding of the memory trace.  相似文献   

2.
Ming Xu 《Studia Logica》2013,101(3):583-599
This paper proves the finite model property and the finite axiomatizability of a class of normal modal logics extending K4.3. The frames for these logics are those for K4.3, in each of which every point has a bounded number of irreflexive successors if it is after an infinite ascending chain of (not necessarily distinct) points.  相似文献   

3.
Disordered eating behaviors and bulimia nervosa were examined in a sample of female Mexican Americans. Results showed that 1.4% to 4.3% could be classified with bulimia. Just over 11% indicated regular binge eating; dieting and exercising were the primary techniques used for weight control. Implications for intervention are briefly discussed.  相似文献   

4.
This study evaluated substance use among a sample of 205 psychiatric inpatients (70 women and 135 men) chosen randomly. The subjects (who had schizophrenia or mood disorders) were evaluated on a confidential questionnaire by interview. Their mean age was 35 yr. (SD= 10.4, range 16 to 69). Of these participants, 76% of the 135 men and 34% of the 70 women admitted use of substances: cigarettes (74% of men, 31.4% of women), opiates (31.9% of men, 4.3% of women), alcohol (23.7% of men, 4.3% of women), hashish (8.9% of men, no women), marijuana (3.7% of men, no women), and cocaine or LSD by none. Only 27% of the women and 63% of the men reported still using substances regularly; some reported using more than one substance. Of the current users, 61.8% of the schizophrenics, 20% of unipolar depressed, and 37.5% of bipolar patients reported current use. The reasons for substance use in order of frequencies of mention were release of tension, seeking pleasure, and need (to avoid withdrawal symptoms) by men and habit, seeking pleasure, and need by women.  相似文献   

5.
Cortical electroencephalographic (EEG) changes induced by ethanol (4.3 and 1.4 g/kg, ip), pentobarbital (50 and 16 mg/kg), and nicotine (1.0 g/kg) were examined in long-sleep (LS) and short-sleep (SS) mice that were genetically selected for differential sleep times induced by a hypnotic dosage of ethanol. Ethanol (4.3 g/kg) caused EEG changes that paralleled the behavioral differences, whereas no differences between selected lines were observed following the activating dose (1.4 g/kg). Data support the notion that the known difference in ethanol sleep times is due not to greater SS sensitivity to ethanol activation but rather to greater LS sensitivity to ethanol hypnosis. No differences between selected lines were observed following 50 mg/kg pentobarbital, which again parallels previous behavioral data. The SS mice were more responsive to pentobarbital activation (16 mg/kg). Nicotine more severely reduced EEG power and heart rate in LS mice; a continuous iv infusion of nicotine elicited a distinct pattern of behavioral stereotypy for each selected line, with more profound motor and reflex depression in LS mice. The lines do not differ in rate of nicotine metabolism, hence they must differ in central nervous system sensitivity to nicotine. Thus, lines of mice selectively bred for differential sensitivity to ethanol also display marked differences in electrophysiological and behavioral responses to nicotine.  相似文献   

6.
中医药的专利权保护   总被引:1,自引:0,他引:1  
中医药为中华民族和世界人民的健康做出了重要贡献,但是由于我国对中医药知识产权保护的落后,我国中医药的珍贵知识财富正为外国大公司无偿地攫取。根据中医药自身的特性,对专利保护的适用、调整、改进及补充作了大胆设想,为我国进一步完善中医药的专利法保护提出了建议。  相似文献   

7.
Task persistence, measured by a composite score of independent teacher, tester and observer reports, was examined using behavioral genetic analysis. Participants included 92 monozygotic and 137 same-sex dizygotic twin pairs in Kindergarten or 1st grade (4.3 to 7.9 years old). Task persistence was widely distributed, higher among older children, positively associated with standardized tests of cognitive performance and achievement, and negatively associated with parents', teachers' and observers' reports of behavioral problems. Cross-sectional analysis indicated a strong developmental shift from shared environment variance among younger children to additive genetic variance in older children.  相似文献   

8.
Cognitive skills and Finnish language inflection   总被引:1,自引:0,他引:1  
Covariation of cognitive processes and mastery of inflectional forms assessed by Berko's method were studied among 2.6–4.3-year-old children. The erroneous inflections produced by the children were analysed in order to discover rules underlying their morphological test responses. The use of the different rules was guided by the children's age and cognitive skills. The effects of contextual task factors varied at different mastery levels of the morphological test. The results indicate the need for concomitant analysis of the interaction between the child's existing level of morphology, cognitive skills and contextual variables of the tasks.  相似文献   

9.
大脑两半球与整体和局部性质的选择性加工   总被引:2,自引:0,他引:2  
张昕  韩世辉 《心理学报》2004,36(5):507-514
研究大脑两半球在加工整体和局部性质中的优势以及两半球能否同时分别选择两个复合刺激的整体和局部性质。实验中把一个复合字母随机呈现在左视野或右视野,或者把两个复合字母同时分别呈现在左视野和右视野。实验一发现,在单侧呈现条件下,被试检测左右视野的整体或局部靶目标的反应时没有显著差别,但在双侧同时呈现条件下,检测右视野局部靶目标比检测左视野局部靶目标时的反应时短。实验二要求被试检测同时呈现在左右视野的整体或局部靶目标,发现当两个视野的靶目标处于同一水平时(整体或局部)反应时较短,两个视野的靶目标处于不同水平时(一侧处于整体水平而另一侧处于局部水平)反应时较长。这些结果提示,当两个复合刺激同时呈现在左右视野时,大脑左半球在选择性加工局部性质时具有优势;左右两半球更容易选择两个复合刺激同一个水平的性质,分别选择两个复合刺激不同水平的性质比较困难。  相似文献   

10.
The validity of self-reported suicide attempt information is undermined by false positives (e.g., incidences without intent to die), or by unreported suicide attempts, referred to as false negatives. In a sample of 1,385 Austrian adults, we explored the occurrence of false positives and false negatives with detailed, probing questions. Removing false positives decreased the rate of suicide attempters from 4.3% to 2.7%. Probing questions also revealed 0.8% false negatives. We recommend using probing questions with both those who report a suicide attempt and those who do not report a suicide attempt to increase the validity of self-reported suicide-related information.  相似文献   

11.
市场经济、道德权利与产权伦理   总被引:6,自引:0,他引:6  
产权伦理是现代市场经济的一个根本性的精神基础,是建立有效的产权制度及其运行机制的重要条件;同时,它是人类道德体系的核心价值理念之一,是基于权利,义务与道德的内在逻辑构建起来的。产权伦理的研究具有重要的理论价值和现实意义,可以构成一门具有特殊的学科特质,研究方法和理论内容的伦理学学科。  相似文献   

12.
本文研究当封闭性作为被试分辨的图形性质时,空间位置不确定性和视野位置对大范围优先性有何影响。实验发现:(1)无论复合刺激呈现在视野的中央或外周.分辨复合刺激的整体性质的反应时(RT)比分辨局部性质的RT短,整体性质对分辨局部性质的反应有较强的干扰作用。相反,局部性质对分辨整体性质的反应的影响较小;(2)刺激位置的不确定对大范围优先性没有显著影响;(3)与周边刺激相比,分辨视野中央的复合刺激的RT较短,但整体性质的RT优势和对局部性质的干扰作用,不受刺激在视野中的位置的影响。这些实验结果揭示了封闭性知觉在大范围优先性中的特殊性。  相似文献   

13.
An examination was instituted to determine the effectiveness of maintenance therapy involving depot neuroplegics in out-patient after-care during an average follow-up of six years. At the time of examination, 172 patients treated with Depot-Lyogen showed statistically significant lower relapse and rehospitalisation rates, a reduction of the productive schizophrenic symptoms, and improved chance of rehabilitation, compared with 55 patients without treatment. In 22% of the 270 patients on Depot-Lyogen, there were early extrapyramidal side-effects, in 4.7% late dyskinesis, and in 4.3% depressive symptoms relating to medication. 35% of the patients did not receive consistent maintenance therapy. The improvement of after-care is discussed.  相似文献   

14.
Rats were trained to ingest corn oil emulsion. Such ingestion was accompanied by intragastric injection either of dilute amino acid (e.g., 4.3 mM L-tryptophan) in one group or saline in a second. No significant difference between the two groups was observed at the end of training. However sudden omission of the amino acid led to a large increase in intake, whereas sudden introduction of the amino acid produced no significant change. It seems that signals for the amount of nutrient ingested can be arbitrarily associated with different nutrients and that the value of such satiety signals is not innately fixed in the amount of feeding inhibition exerted.  相似文献   

15.
Change in task persistence was assessed in two annual assessments using teachers', testers', and observers' ratings. Participants included 79 monozygotic and 116 same-sex dizygotic twin pairs who were in Kindergarten or 1st grade (4.3 to 7.9 years old) at the initial assessment. Task persistence was widely distributed and higher among older children and girls. Overall, there was modest growth in persistence over time, and moderate stability of individual differences. Most of the stability was accounted for by genetic influences, whereas most of the change was accounted for by nonshared environment, including an association with observed differential maternal warm supportive behavior.  相似文献   

16.
Blackburn等的ModalLogic是一部优秀的中高阶教材,但是该书中对Bull定理的证明存在着不少疏漏。本文对之进行了修正,同时给出关键步骤的简化证明。  相似文献   

17.
Evidence suggests Jonathan Edwards' adherence to a version of the penal substitution theory of atonement. Evidence also suggests that Edwards' version of the penal substitution theory requires certain metaphysical commitments about the nature of Christ's relationship to the elect, echoing those issued in his Original Sin 4.3, and elsewhere, regarding the relationship of Adam to his posterity. In what follows, I argue that such evidence points to Edwards' adherence to what has more recently been described in the literature of contemporary philosophical theology as an account of realist penal substitution.  相似文献   

18.
公立医院产权制度改革理论与模式分析   总被引:7,自引:0,他引:7  
建立与市场经济体制相适应的医疗机构管理体制,要进一步认识医院产权制度改革的必要性、目的和意义,客观地分析评价产权制度改革的各种模式,认真思考和妥善处理医院产权制度改革中面临的问题,逐步推进公立医院产权制度的改革.  相似文献   

19.
视知觉组织在整体知觉中的作用--脑损伤病人的实验研究   总被引:1,自引:0,他引:1  
本实验研究大脑损伤如何影响复合图形的整体知觉。三例病人脑损伤部位分别在大脑枕区、顶区、颞区、额区及基底节和豆状核。复合图形被呈现给病人和正常对照被试。强迫选择识别等任务表明,当空间相邻性决定局部图形的知觉组织时,病人识别整体性质的正确率高于(ZD和FL)或略底于(GK)识别局部性质的正确率;当形状相似性决定局部图形的知觉组织时,病人识别整体性质的正确率显著降低,而识别局部性质的正确率受到的影响较小。在同样的任务中正常被试识别整体和局部性质的正确率受知觉组织因素的影响很小。这些结果提示大脑损伤对整体知觉的破坏可能主要通过影响基于形状相似性的知觉组织实现。  相似文献   

20.
The present study evaluated the effect of a brief mindfulness-based preventive intervention on (a) dispositional (MAAS; Brown & Ryan, 2003) and state (SMS; Tanay & Bernstein, 2010) mindfulness; (b) putative proximal factors/processes engendered through the development of mindfulness, including increased decentering (EQ-D; Fresco et al., 2007) and reduced experiential avoidance (AAQ; Hayes et al., 2004); and (c) distal mood and anxiety vulnerability factors, including reduced depression-related dysfunctional attitudes, (DAS; de Graaf, Roelofs, & Huibers, 2009), anxiety sensitivity (ASI-3; Taylor et al., 2007), and negative affectivity (PANAS-NA; Watson, Clark, & Tellegen, 1988) among a university-community sample in Israel. Fifty-three adult participants between the ages of 20 and 52 (M(age)=25.2 years, SD(age)=4.3 years; 65.4% women) were recruited from the Haifa University community. Nineteen participants were randomly assigned to an experimental condition (M(age)=25.3 years, SD(age)=4.3 years; 66% women) and studied prospectively over the course of a four-session (21-day) mindfulness skills training intervention; and 34 participants were randomly assigned to a no-intervention (control) condition (M(age)=24.9 years, SD(age)=2.4years; 64.7% women) and studied prospectively. Findings demonstrate statistically robust and clinically significant relations between mindfulness and the theorized proximal and distal mood and anxiety vulnerability factors. Findings are discussed with respect to their theoretical implications for better understanding mindfulness-psychopathology vulnerability relations, clinical implications for larger-scale universal and selective transdiagnostic prevention efforts, and future directions for this area of research.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号