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   24158篇
  免费   376篇
  国内免费   15篇
教育   17332篇
科学研究   2094篇
各国文化   247篇
体育   1950篇
综合类   13篇
文化理论   184篇
信息传播   2729篇
  2022年   185篇
  2021年   276篇
  2020年   409篇
  2019年   632篇
  2018年   849篇
  2017年   839篇
  2016年   736篇
  2015年   450篇
  2014年   685篇
  2013年   4726篇
  2012年   667篇
  2011年   684篇
  2010年   502篇
  2009年   517篇
  2008年   572篇
  2007年   505篇
  2006年   455篇
  2005年   447篇
  2004年   397篇
  2003年   377篇
  2002年   374篇
  2001年   495篇
  2000年   427篇
  1999年   374篇
  1998年   213篇
  1997年   219篇
  1996年   258篇
  1995年   247篇
  1994年   201篇
  1993年   219篇
  1992年   334篇
  1991年   321篇
  1990年   313篇
  1989年   306篇
  1988年   267篇
  1987年   309篇
  1986年   277篇
  1985年   315篇
  1984年   254篇
  1983年   225篇
  1982年   198篇
  1981年   171篇
  1980年   173篇
  1979年   271篇
  1978年   192篇
  1977年   175篇
  1976年   157篇
  1975年   144篇
  1974年   152篇
  1971年   143篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
41.
42.
43.
44.
In this article, the author explores the "algebra for all" issue to raise awareness about the many facets of this dilemma facing educators at the middle and high school levels. She discusses both sides of this controversial issue, especially regarding its impact on students' futures relative to higher education and employment. The author concludes that unless dramatic reform occurs in the delivery of algebra so that all students benefit from such instruction, students must make the decision to take algebra based on individual needs, interests, and desires.  相似文献   
45.
The study assessed the effects of achievement standards, and choice of such standards, on mathematics performance in conditions where no tangible rewards were presented for reaching such standards. Elementary, junior high, and high school students performed a multiplication task in conditions where they chose standards, had standards imposed by an experimenter, or had no standards. Results demonstrated that high school students worked more multiplication problems when they chose standards than when identical standards were imposed by an experimenter or when no standards were present. Moreover, male students who chose standards worked more problems than did male students who had no standards; this effect was not found for female students.  相似文献   
46.
This paper illustrates the use of a Scheffé-like multivariate post hoc procedure known as the Roy-Bose or simultaneous confidence interval procedure. This method is contrasted with the use of Bonferroni or planned linear combinations for the one- and two-sample cases. The Roy-Bose procedure also is compared to the more frequently employed univariate F tests for post hoc analysis.  相似文献   
47.
48.
49.
Abstract

Athletes at high risk of groin strains in sports such as hockey and soccer often choose to wear shorts with directional compression to aid in prevention of or recovery from hip adductor strains. Large, eccentric contractions are known to result in or exacerbate strain injuries, but it is unknown if these shorts have a beneficial effect on hip adductor muscle activity. In this study, surface electromyography (EMG) of the adductor longus and ground reaction force (GRF) data were obtained simultaneously on 29 healthy individuals without previous history of serious injury while performing unanticipated 45° run-to-cut manoeuvres in a laboratory setting wearing shorts with non-directional compression (control, HeatGear, Under Armour, USA) or shorts with directional compression (directional, CoreShort PRO, Under Armour, USA), in random order. Average adductor activity in the stance leg was significantly lower in the directional condition than in the control condition during all parts of stance phase (all P < 0.042). From this preliminary analysis, wearing directional compression shorts appears to be associated with reduced stance limb hip adductor activity. Athletes seeking to reduce demand on the hip adductors as they approach full return to activities may benefit from the use of directional compression shorts.  相似文献   
50.
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