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   30843篇
  免费   433篇
  国内免费   30篇
教育   21719篇
科学研究   2932篇
各国文化   305篇
体育   2675篇
综合类   19篇
文化理论   258篇
信息传播   3398篇
  2022年   223篇
  2021年   319篇
  2020年   477篇
  2019年   742篇
  2018年   1021篇
  2017年   1007篇
  2016年   883篇
  2015年   553篇
  2014年   833篇
  2013年   5889篇
  2012年   786篇
  2011年   811篇
  2010年   604篇
  2009年   616篇
  2008年   682篇
  2007年   645篇
  2006年   576篇
  2005年   529篇
  2004年   485篇
  2003年   497篇
  2002年   461篇
  2001年   601篇
  2000年   514篇
  1999年   484篇
  1998年   269篇
  1997年   272篇
  1996年   336篇
  1995年   303篇
  1994年   267篇
  1993年   273篇
  1992年   442篇
  1991年   422篇
  1990年   410篇
  1989年   409篇
  1988年   352篇
  1987年   398篇
  1986年   381篇
  1985年   420篇
  1984年   337篇
  1983年   324篇
  1982年   288篇
  1981年   254篇
  1980年   237篇
  1979年   395篇
  1978年   278篇
  1977年   265篇
  1976年   248篇
  1975年   215篇
  1974年   227篇
  1971年   199篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
11.
How accurate is the reported percent of students’reaching standards at the school level? How are standard errors for these statistics computed? How do estimates vary with choice of generalizability model?  相似文献   
12.
In recent years university presses have undergone some significant changes, such as expansion of their scope to include materials that may have appeal beyond the scholarly market. This article investigates, through the use of a survey of university libraries, the acquisition of university press products by libraries. In general, recent years have been changes in the relationship between university presses and libraries that have resulted in fewer items being purchased by the libraries.  相似文献   
13.
14.
This study examined the argument patterns that result when Israeli-Jews and Palestinians confront each other during group dialogues. We tested predictions derived from two theories. The first was a theory of cultural communication which predicted that Israeli-Jews and Palestinians would argue in a manner consistent with their respective cultural communication codes known as dugri and musayra respectively. Thus, the Israeli-Jews were expected to be assertive and the Palestinians more accommodating. The second theory was rooted in majority/minority power relations and predicted the opposite. The data were generated from reconciliation-based dialogue groups of Israeli-Jews and Palestinians. Communicative acts were coded according to the Conversational Argument Coding Scheme. Analysis of covariance was used to determine which patterns of argument distinguished the groups, and to identify variance attributable to lag sequences and individuals. The results were supportive of predictions from majority/minority power relations.  相似文献   
15.
16.
Cerebral activity, as reflected by power in the alpha waveband (8-13 Hz), was examined prior to the performance of three tasks with different effort and accuracy requirements. The study aimed to further investigate changes in activity observed in an earlier study in which expert karate performers exhibited significant increases in alpha band power during preparation for a training task. In contrast to the earlier research, the high effort task produced a significant decrease in 'alpha' power prior to performance. 'Alpha' power prior to the high accuracy task showed significant differences mediated by the outcome. Successful performance was preceded by higher levels of 'alpha' power than unsuccessful attempts. The reported use of a cognitive strategy on the first task produced a significant difference in activity, lower alpha power being associated with the use of such a technique.  相似文献   
17.
18.
19.
20.
The purpose of this investigation was to describe the morphological parameters that characterize elite age group divers. Comparisons are made to normative age group data from the Coquitlam Growth Study and the constancy of important characteristics from age group to age group is examined. Data were collected on 27 male and 28 female elite divers who participated in the 1990 North American Age Group Diving Championships. Body build, body composition and skinfold corrected diameters were determined from 36 anthropometric parameters and analysed by ANOVA, t-test and Phantom z-scores procedures. All age groups except the 14- to 15-year-old males were significantly (P < or = 0.05) shorter than their norms but recorded higher androgyny index values. The estimated relative muscle mass increased significantly (P < or = 0.05) with age for males at all ages (40.8-46.3%). The 16- to 18-year-old females had a significantly (P < or = 0.05) larger relative muscle component compared to the younger age groups (40.1-38.4%). When normalized for height, active tissue development of the extremities was comparable between the sexes except in the forearm. The results indicate that at all age levels short stature is an important characteristic for divers. Analysis of regional active tissue development provides further insight into sport-specific prerequisites for success at elite levels.  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