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   13752篇
  免费   220篇
  国内免费   11篇
教育   9517篇
科学研究   1697篇
各国文化   114篇
体育   1033篇
综合类   17篇
文化理论   162篇
信息传播   1443篇
  2021年   136篇
  2020年   208篇
  2019年   288篇
  2018年   415篇
  2017年   438篇
  2016年   399篇
  2015年   259篇
  2014年   378篇
  2013年   2271篇
  2012年   347篇
  2011年   323篇
  2010年   305篇
  2009年   267篇
  2008年   293篇
  2007年   295篇
  2006年   277篇
  2005年   241篇
  2004年   260篇
  2003年   238篇
  2002年   245篇
  2001年   317篇
  2000年   340篇
  1999年   260篇
  1998年   146篇
  1997年   189篇
  1996年   175篇
  1995年   121篇
  1994年   133篇
  1993年   117篇
  1992年   198篇
  1991年   184篇
  1990年   220篇
  1989年   213篇
  1988年   182篇
  1987年   197篇
  1986年   177篇
  1985年   208篇
  1984年   151篇
  1983年   133篇
  1982年   130篇
  1981年   113篇
  1980年   113篇
  1979年   179篇
  1978年   132篇
  1977年   116篇
  1976年   91篇
  1975年   96篇
  1974年   96篇
  1973年   91篇
  1971年   91篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
Looking for laws     
S. French 《Metascience》2006,15(3):437-469
  相似文献   
22.
What legal issues may arise in setting content or performance standards? What precedents are relevant? What practices are defensible?  相似文献   
23.
Conclusion Computer-based career systems should be the focal point of popular, and effective career development initiatives which are of tremendous benefit to individuals. Such initiatives also have the potential to significantly reduce public expenditures and enhance the nation's competitive position internationally. The key lies in helping people understand that we can no longer afford to neglect the career development needs of Americans.I am most grateful for this opportunity to share my thoughts with you. I encourage you to promote the use of computer-based career systems by defining their benefits in economic terms. However, be sure you can prove your system does more than simply entertain its users, or leave them with extensive computer printouts.Phillip S. Jarvis is Manager, Careerware Research and Product Design, STM Systems Corp., Ottawa, Ontario, Canada and the author of CHOICES. This is the text of a paper presented to the Annual Conference of the Association of Computer-Based Systems for Career Information ((ACSCI) in St. Louis, Missouri on December 2, 1988.  相似文献   
24.
There is limited information on the anthropometry, strength, endurance and flexibility of female rock climbers. The aim of this study was to compare these characteristics in three groups of females: Group 1 comprised 10 elite climbers aged 31.3 +/- 5.0 years (mean +/- s) who had led to a standard of 'hard very severe'; Group 2 consisted of 10 recreational climbers aged 24.1 +/- 4.0 years who had led to a standard of 'severe'; and Group 3 comprised 10 physically active individuals aged 28.5 +/- 5.0 years who had not previously rock-climbed. The tests included finger strength (grip strength, finger strength measured on climbing-specific apparatus), flexibility, bent arm hang and pull-ups. Regression procedures (analysis of covariance) were used to examine the influence of body mass, leg length, height and age. For finger strength, the elite climbers recorded significantly higher values (P < 0.05) than the recreational climbers and non-climbers (four fingers, right hand: elite 321 +/- 18 N, recreational 251 +/- 14 N, non-climbers 256 +/- 15 N; four fingers, left hand: elite 307 +/- 14 N, recreational 248 +/- 12 N, non-climbers 243 +/- 11 N). For grip strength of the right hand, the elite climbers recorded significantly higher values than the recreational climbers only (elite 338 +/- 12 N, recreational 289 +/- 10 N, non-climbers 307 +/- 11 N). The results suggest that elite climbers have greater finger strength than recreational climbers and non-climbers.  相似文献   
25.
26.
27.
28.
29.
30.
While bookstores play the vital role in book distribution, little attention has been paid to concentration and conglomerate ownership in the retail book trade. In 1958, one-store book firms accounted for nearly 80 percent of book sales; by 1982 that figure had fallen to 26 percent even though single-store retailers continue to account for a majority of all bookstore outlets. Today the chains control at least 54 percent of bookstore sales. Buoyed by discriminatory discounts and publisher-subsidized advertising campaigns, the chains’ dramatic growth seems likely to continue despite the fact that they are less profitable than independent booksellers. The chains’ marketing orientation fits well with changes in the broader publishing industry, as publishers seek to rationalize operations in order to improve the bottom line. As books become just another commodity, sold through increasingly centralized and monopolized channels, access for alternative and minority voices is being for-closed.  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