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   23366篇
  免费   416篇
  国内免费   33篇
教育   16888篇
科学研究   2018篇
各国文化   217篇
体育   1774篇
综合类   34篇
文化理论   196篇
信息传播   2688篇
  2022年   132篇
  2021年   236篇
  2020年   372篇
  2019年   514篇
  2018年   728篇
  2017年   803篇
  2016年   734篇
  2015年   458篇
  2014年   599篇
  2013年   4444篇
  2012年   587篇
  2011年   657篇
  2010年   505篇
  2009年   491篇
  2008年   542篇
  2007年   519篇
  2006年   460篇
  2005年   401篇
  2004年   378篇
  2003年   345篇
  2002年   395篇
  2001年   436篇
  2000年   406篇
  1999年   410篇
  1998年   240篇
  1997年   241篇
  1996年   266篇
  1995年   220篇
  1994年   219篇
  1993年   214篇
  1992年   315篇
  1991年   312篇
  1990年   341篇
  1989年   320篇
  1988年   306篇
  1987年   255篇
  1986年   267篇
  1985年   339篇
  1984年   275篇
  1983年   261篇
  1982年   209篇
  1981年   222篇
  1980年   184篇
  1979年   249篇
  1978年   218篇
  1977年   201篇
  1976年   165篇
  1975年   132篇
  1974年   125篇
  1973年   152篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
33.
The project of studying children in order to understand them, which lies at the heart of contemporary thinking about children and their education, is misconceived. It rests, jrst of all, upon a false belief that we can only come to know something properly by deliberately and systematically pursuing knowledge of it. Secondly, it offers a paradigm of knowing children which justifies parents and teachers in not giving themselves to children. By re-interpreting the problems that adults experience with children as technical, as arising from lack of information about them, it ignores the personal and moral dimension of adults' relations with children and thus further alienates them from one another.  相似文献   
34.
35.
This article discusses the changing relationships of authors and publishers, the current trends and challenges they face, and the direction of these relationships in the future. As the STM publishing industry finds itself in the midst of significant technological and economic changes, this article provides background to these changes and looks at the key elements, including open access business development, institutional repository trends, and emerging public financing policies in the future.  相似文献   
36.
37.
This investigation was undertaken in an effort to establish physiological characteristics of soccer players and to relate them to positional roles. A total of 135 footballers (age 24.4 +/- 4.6 years) were assessed for body mass, % body fat, haemoglobin, maximal oxygen uptake (VO2 max), leg power, anaerobic capacity and speed prior to an English league season. The sample included 13 goalkeepers, 22 full-backs, 24 centre-backs, 35 midfield players and 41 forwards. The goalkeepers were significantly heavier (86.1 +/- 5.5 kg; P < 0.01) than all groups except the centre-backs, had significantly higher estimated body fat percentages than centre-backs, forwards, midfield players (P < 0.01) or full-backs (P < 0.05), significantly lower estimated VO2 max values (56.4 +/- 3.9 ml kg-1 min-1; P < 0.01) and were slowest over 60 m (12.71 +/- 0.42 s). The midfield players had the highest predicted VO2 max values (61.4 +/- 3.4 ml kg-1 min-1), this being significantly greater (P < 0.05) than for the centre-backs. The forwards were the fastest group over 60 m (12.19 +/- 0.30 s), being significantly quicker than goalkeepers or centre-backs (P < 0.01) and full-backs (P < 0.05). Anaerobic power, as well as knee extensor torques (corrected for body mass) and extensor-flexor ratios, were similar between groups. No difference in estimated body fat percentage was observed between any of the outfield players, and haemoglobin concentrations were similar among players of all positions.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
38.
39.
40.
Ordinary markets allow parties, not the state, to value property and projects. But they do not account for subjective value in such traditional contexts as condemnation. An awareness of these nonmarket values helps overcome any categorical opposition to the use of the contingent valuation method (CVM) to value cultural and environmental resources. But accurate CVM should measure all values, positive or negative, tononowners; it should apply generally to any substitute projects; and it should seek to account for diminishing marginal value of additional resource units. CVM should be used only to aggregate nonmarket preferences, not to skew the political debate to cultural or environmental objectives.  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