首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   690篇
  免费   31篇
  2023年   3篇
  2022年   6篇
  2021年   13篇
  2020年   19篇
  2019年   11篇
  2018年   23篇
  2017年   19篇
  2016年   23篇
  2015年   18篇
  2014年   21篇
  2013年   66篇
  2012年   35篇
  2011年   40篇
  2010年   22篇
  2009年   32篇
  2008年   22篇
  2007年   28篇
  2006年   30篇
  2005年   23篇
  2004年   27篇
  2003年   25篇
  2002年   14篇
  2001年   9篇
  2000年   7篇
  1999年   10篇
  1998年   7篇
  1997年   11篇
  1996年   6篇
  1995年   10篇
  1994年   4篇
  1993年   7篇
  1992年   6篇
  1991年   10篇
  1988年   7篇
  1987年   7篇
  1986年   7篇
  1985年   5篇
  1984年   4篇
  1983年   6篇
  1982年   6篇
  1981年   6篇
  1980年   8篇
  1979年   7篇
  1977年   3篇
  1976年   5篇
  1975年   5篇
  1974年   5篇
  1972年   3篇
  1969年   3篇
  1958年   3篇
排序方式: 共有721条查询结果,搜索用时 15 毫秒
191.
Research on Child and Adolescent Psychopathology - Original definitions of psychopathy suggest the existence of two variants that present with distinct clinical features among antisocial adults,...  相似文献   
192.
Several recent studies have supported the existence of a link between spatial processing and some aspects of mathematical reasoning, including mental arithmetic. Some of these studies suggested that people are more accurate when performing arithmetic operations for which the operands appeared in the lower-left and upper-right spaces than in the upper-left and lower-right spaces. However, this cross-over Horizontality × Verticality interaction effect on arithmetic accuracy was only apparent for multiplication, not for addition. In these studies, the authors used a spatio-temporal synchronous operand presentation in which all the operands appeared simultaneously in the same part of space along the horizontal and vertical dimensions. In the present paper, we report studies designed to investigate whether these results can be generalized to mental arithmetic tasks using a spatio-temporal asynchronous operand presentation. We present three studies in which participants had to solve addition (Study 1a), subtraction (Study 1b), and multiplication (Study 2) in which the operands appeared successively at different locations along the horizontal and vertical dimensions. We found that the cross-over Horizontality × Verticality interaction effect on arithmetic accuracy emerged for addition but not for subtraction and multiplication. These results are consistent with our predictions derived from the spatial polarity correspondence account and suggest interesting directions for the study of the link between spatial processing and mental arithmetic performances.  相似文献   
193.
Understanding culture across species   总被引:1,自引:0,他引:1  
Recent claims of culture in great apes have provoked fervent argument about the 'true' definition of culture, most of which has been unhelpful. Instead, a range of definitions should be used to explore different aspects of the cognitive processes that together result in human culture, many of which can be productively studied in non-humans. A richer cognitive account of the contents of culture needs to be developed and used to compare animal and human cultures, instead of sterile searching for a cognitive Rubicon between them. Exploring six views of culture, this article highlights the fundamental contrast of whether culture evolves as a by-product of cumulative change in cognitive mechanisms, or whether it is actively selected for its advantages.  相似文献   
194.
In two experiments we investigated the effects of voluntary movements on temporal haptic perception. Measures of sensitivity (JND) and temporal alignment (PSS) were obtained from temporal order judgments made on intermodal auditory-haptic (Experiment 1) or intramodal haptic (Experiment 2) stimulus pairs under three movement conditions. In the baseline, static condition, the arm of the participants remained stationary. In the passive condition, the arm was displaced by a servo-controlled motorized device. In the active condition, the participants moved voluntarily. The auditory stimulus was a short, 500Hz tone presented over headphones and the haptic stimulus was a brief suprathreshold force pulse applied to the tip of the index finger orthogonally to the finger movement. Active movement did not significantly affect discrimination sensitivity on the auditory-haptic stimulus pairs, whereas it significantly improved sensitivity in the case of the haptic stimulus pair, demonstrating a key role for motor command information in temporal sensitivity in the haptic system. Points of subjective simultaneity were by-and-large coincident with physical simultaneity, with one striking exception in the passive condition with the auditory-haptic stimulus pair. In the latter case, the haptic stimulus had to be presented 45ms before the auditory stimulus in order to obtain subjective simultaneity. A model is proposed to explain the discrimination performance.  相似文献   
195.
We evaluated the differential effects of 2 variations of a stimulusstimulus pairing procedure on the vocalizations of 2 children with autism. For both participants, presenting 1 sound per pairing trial resulted in a higher rate of vocalizations than 3 sounds per pairing trial.  相似文献   
196.
Over the prior decade, structural change efforts have become an important component of community-based HIV prevention initiatives. However, these efforts may not succeed when structural change initiatives encounter political resistance or invoke conflicting values, which may be likely when changes are intended to benefit a stigmatized population. The current study sought to examine the impact of target population stigma on the ability of 13 community coalitions to achieve structural change objectives. Results indicated that coalitions working on behalf of highly stigmatized populations had to abandon objectives more often than did coalitions working for less stigmatized populations because of external opposition to coalition objectives and resultant internal conflict over goals. Those coalitions that were most successful in meeting external challenges used opposition and conflict as transformative occasions by targeting conflicts directly and attempting to neutralize oppositional groups or turn them into strategic allies; less successful coalitions working on behalf of stigmatized groups struggled to determine an appropriate response to opposition. The role of conflict transformation as a success strategy for working on behalf of stigmatized groups is discussed.  相似文献   
197.
Research on social dilemmas has largely been concerned with whether, and under what conditions, selfish decisions by autonomous individuals jointly result in socially inefficient outcomes. By contrast, considerably less emphasis has been placed on the extent of the inefficiency in those outcomes relative to the social optimum, and how the extent of inefficiency in theory compares with what is observed in experiments or practice. In this expository article, we introduce and subsequently extend the price of anarchy (PoA), an index that originated in studies on communication in computer science, and illustrate how it can be used to characterize the extent of inefficiency in social dilemmas. A second purpose of our article is to introduce a class of social dilemmas that occur when individuals selfishly choose routes in networks, and illustrate how the concept of PoA can be helpful in studying them.  相似文献   
198.
Objective: To test the hypothesis that people with chronic fatigue syndrome (CFS) would differ significantly from a healthy control group on measures of general personality and perfectionism, specifically on measures of neuroticism and unhealthy perfectionism. Method: A total of 27 female CFS outpatients and 30 female healthy controls completed questionnaires, including the NEO Personality Inventory-Revised, the Multi-dimensional Perfectionism Scale and measures of anxiety and depression. Results: The CFS group was significantly more fatigued, anxious and depressed than healthy controls. They scored significantly higher on neuroticism and unhealthy perfectionism. Healthy and unhealthy perfectionism were positively correlated in the CFS group, but not in the control group. Conclusion: The present study confirms the link between neuroticism and fatigue and finds a link between unhealthy perfectionism and fatigue. A ‘healthy trait’, such as healthy perfectionism, when coupled with evaluative concerns is not necessarily healthy in a fatigued population. Researchers and clinicians should note the context in which apparently benign traits are expressed, and how they interact with other traits.  相似文献   
199.
Abstract

The structural analysis by convergent-beam electron diffraction is described for a weak orthorhombic superlattice observed in both mineral and synthetic samples of NiAs. The three equivalent directions for the commensurate wavevector, q = ?(a? + b?), defined a domain structure within the hexagonal subcell. Within a single domain, the symmetry around the c axis was reduced from 6mm to 2mm. The internal structure of higher-order Laue-zone reflections in diffraction patterns recorded at 100 K was used to associate a specific phonon eigenvector or condensed soft mode with the atomic displacement pattern.  相似文献   
200.
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