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   9805篇
  免费   128篇
  国内免费   6篇
教育   6536篇
科学研究   1146篇
各国文化   341篇
体育   780篇
综合类   4篇
文化理论   68篇
信息传播   1064篇
  2021年   96篇
  2020年   144篇
  2019年   208篇
  2018年   264篇
  2017年   299篇
  2016年   263篇
  2015年   160篇
  2014年   211篇
  2013年   1770篇
  2012年   212篇
  2011年   222篇
  2010年   191篇
  2009年   197篇
  2008年   257篇
  2007年   230篇
  2006年   195篇
  2005年   178篇
  2004年   191篇
  2003年   135篇
  2002年   121篇
  2001年   157篇
  2000年   188篇
  1999年   161篇
  1998年   88篇
  1997年   91篇
  1996年   77篇
  1995年   67篇
  1994年   73篇
  1993年   84篇
  1992年   143篇
  1991年   148篇
  1990年   151篇
  1989年   156篇
  1988年   121篇
  1987年   118篇
  1986年   116篇
  1985年   156篇
  1984年   128篇
  1983年   121篇
  1982年   99篇
  1981年   74篇
  1980年   81篇
  1979年   129篇
  1978年   86篇
  1977年   81篇
  1976年   74篇
  1974年   84篇
  1973年   72篇
  1971年   69篇
  1968年   64篇
排序方式: 共有9939条查询结果,搜索用时 15 毫秒
101.
The aim of the this study was to establish age- and gender-specific physical fitness normative values and to compare percentiles and Z scores values in a large, nationwide sample of Greek children aged 6–18 years. From March 2014 to May 2014, a total of 424,328 boys and girls aged 6–18 years who attended school in Greece were enrolled. The studied sample was representative, in terms of age–sex distribution and geographical region. Physical fitness tests (i.e. 20?m shuttle run test (SRT), standing long jump, sit and reach, sit-ups, and 10?×?5?m SRT) were performed and used to calculate normative values, using the percentiles of the empirical distributions and the lambda, mu, and sigma statistical method. Normative values were presented as tabulated percentiles for five health-related fitness tests based on a large data set comprising 424,328 test performances. Boys typically scored higher than girls on cardiovascular endurance, muscular strength, muscular endurance, and speed/agility, but lower on flexibility (all p values <0.001). Older boys and girls had better performances than younger ones (p?相似文献   
102.
103.
104.
105.
We contrast the current science education reform effort with the reforms of the 1960s and suggest how the current effort could be enhanced. We identify insights from recent research that we believe can inform the reform process, in particular, to reach all science students and also impart a cohesive view of science. We propose an alternative models view of scientific explanation and show how this view would contribute to reforms of (1) course goals, (2) social aspects of science learning, (3) instructional practices, and (4) roles for technology.This paper summarizes discussions and debates that the authors have had over the last few years. The dialogue stems, in part, from our joint participation in the American Educational Research Association Special Interest Group on Education in Science and Technology (AERA SIG:EST) leadership. This paper communicates the spirit of our thinking and does not necessarily reflect the view of SIG:EST, or any other organization.We gratefully acknowledge the support of National Science Foundation Grant MDR-9253462 in work related to this paper. We appreciate helpful comments from Eileen Lewis and the Computer as Learning Partner group.This material is based upon research supported by the National Science Foundation under grant RED-9155744. Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the authors and not necessarily reflect the views of the National Science Foundation.  相似文献   
106.
107.
OBJECTIVE: The purpose of this study is to examine processing of facial emotions in a sample of maltreated children showing high rates of post-traumatic stress disorder (PTSD). Maltreatment during childhood has been associated independently with both atypical processing of emotion and the development of PTSD. However, research has provided little evidence indicating how high rates of PTSD might relate to maltreated children's processing of emotions. METHOD: Participants' reaction time and labeling of emotions were measured using a morphed facial emotion identification task. Participants included a diverse sample of maltreated children with and without PTSD and controls ranging in age from 8 to 15 years. Maltreated children had been removed from their homes and placed in state custody following experiences of maltreatment. Diagnoses of PTSD and other disorders were determined through combination of parent, child, and teacher reports. RESULTS: Maltreated children displayed faster reaction times than controls when labeling emotional facial expressions, and this result was most pronounced for fearful faces. Relative to children who were not maltreated, maltreated children both with and without PTSD showed enhanced response times when identifying fearful faces. There was no group difference in labeling of emotions when identifying different facial emotions. CONCLUSIONS: Maltreated children show heightened ability to identify fearful faces, evidenced by faster reaction times relative to controls. This association between maltreatment and atypical processing of emotion is independent of PTSD diagnosis.  相似文献   
108.
The problem of a mathematician who walks from her home to her office and changes her mind repeatedly during this walk is discussed. Stochastic generalizations of this problem can be used to model many real-life situations.  相似文献   
109.
Rats were exposed twice in a rotated sequence to a series of six mazes, consisting of hexagonal alleys, balanced for different alley length and structural complexity. Locomotor activity increased with alley length and decreased with structural complexity of the mazes. Locomotion became less stereotyped with increased experience, showing an increasing number of turns, less constant velocity, loss of the initial preference for outward leading alleys and weakening of the forward tendency at reentry from side alleys into hexagonal alleys. In contrast to these qualitative changes of locomotion, the amount of activity remained almost unchanged throughout the experiment. The results suggest that these increases in locomotion complexity depend upon complex interactions between experience and stimulus content of the mazes.  相似文献   
110.
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