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   10281篇
  免费   120篇
  国内免费   122篇
教育   6579篇
科学研究   1236篇
各国文化   90篇
体育   1645篇
综合类   19篇
文化理论   69篇
信息传播   885篇
  2021年   85篇
  2020年   163篇
  2019年   215篇
  2018年   297篇
  2017年   290篇
  2016年   274篇
  2015年   196篇
  2014年   242篇
  2013年   1593篇
  2012年   218篇
  2011年   225篇
  2010年   194篇
  2009年   218篇
  2008年   193篇
  2007年   180篇
  2006年   201篇
  2005年   171篇
  2004年   381篇
  2003年   354篇
  2002年   335篇
  2001年   404篇
  2000年   241篇
  1999年   164篇
  1998年   107篇
  1997年   98篇
  1996年   96篇
  1995年   107篇
  1994年   104篇
  1993年   81篇
  1992年   152篇
  1991年   118篇
  1990年   137篇
  1989年   149篇
  1988年   110篇
  1987年   130篇
  1986年   120篇
  1985年   137篇
  1984年   119篇
  1983年   125篇
  1982年   96篇
  1981年   81篇
  1980年   91篇
  1979年   134篇
  1978年   87篇
  1977年   72篇
  1976年   89篇
  1975年   65篇
  1974年   72篇
  1973年   68篇
  1971年   66篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Classroom     
In this section of Resonance, we invite readers to pose questions likely to be raised in a classroom situation. We may suggest strategies for dealing with them, or invite responses, or both. “Classroom” is equally a forum for raising broader issues and sharing personal experiences and viewpoints on matters related to teaching and learning science. This project was done as part of the Research Education Advancement Programme held over weekends at the Bangalore Association for Science Education, Jawaharlal Nehru Planetarium, Bangalore.  相似文献   
992.
Classroom     
  相似文献   
993.
994.
This study examined the theory of change of the ACT Raising Safe Kids parenting program, including whether intervention effects on children's behavior problems were explained by improvements in mothers’ reported parenting practices, as well as whether baseline child behavior problems moderated these relations. Adult mothers of 3-to 8-year-old Brazilian children were assigned to the intervention (n = 97) or control (n = 46) groups. Results showed that the intervention improved mothers' perceptions of their parenting practices (positive discipline, emotional and behavioral regulation, and communication). Intervention-induced reductions in children’s internalizing and externalizing behavior problems were mediated by improvements in mothers’ emotional and behavioral regulation. Program effects were strongest for children with high levels of baseline behavior problems.  相似文献   
995.
Burns  James P.  Cruz  Christopher 《Prospects》2021,51(1-3):219-231
PROSPECTS - This article focuses on the possibilities through which curriculum on the other side of the Covid-19 pandemic might contribute more proactively to future social and political crises...  相似文献   
996.
997.
An adequate antioxidant reserve which is usually present in a vegetarian diet is associated with higher life expectancy. On the other hand habitual consumption of fish is associated with lower risk of cardiovascular diseases which is attributed to the polyunsaturated fatty acids (PUFA) present in it. However the PUFA are readily susceptible to oxidation leading to the formation of free radicals which is known to be involved in the causation of several diseases. The oxidant-antioxidant status of 23 vegetarians and 22 fish eaters was studied by determining the plasma lipid peroxides measured as malondialdehyde (MDA) and the antioxidants, viz. glutathione (GSH), ascorbic acid, ceruloplasmin and uric acid. Results show that the ascorbic acid values were significantly higher in vegetarians. In addition, MDA correlated negatively with ascorbic acid only in vegetarians. However, correlation of MDA with glutathione showed a significant negative correlation only in fish eaters. There was no statistically significant difference in the MDA, GSH, ceruloplasmin and uric acid levels. The mechanism behind these findings are not clear and needs to be explored.  相似文献   
998.
Until comparatively recently the only systematic means of discovering new biologically active substances was laboriously to screen very large numbers of compounds. Now, however, computer graphics is replacing this crude shotgun technique and making it possible to display in some detail the conformation of substances before they are synthesized and determine how far they match the essential features of those in which the biological activity desired has already been demonstrated.  相似文献   
999.
This contribution proposes a revised framework for understanding and analyzing the process of technology transfer in the perspective of the knowledge-based economy (KBE). The underlying hypothesis is that the context of the knowledge-based economy introduces a major shift in the way technology transfer is conceived. The traditional model of technology transfer was based on the vision of technology moving from one well-defined economic unit to another well-defined unit. We suggest that in the new perspective technology transfer is essentially considered as a specific knowledge-transfer process that depends on the ways firms and other institutions manage knowledge, in particular the co-evolution of their absorptive capabilities and their knowledge-transmission strategies. To support the theoretical analysis, we analyze the business case of Nortel Networks over the past 50 years.  相似文献   
1000.
Fluorescent dyes can be used as cell probes which bind, according to their chemical structure, to particular subcellular regions of lymphocytes. Because of their sensitivity to variations in the local molecular environment, expressed by changes in fluorescence emission, they provide a means of studying the early events of lymphocyte activation to antigens and mitogens. The technology also yields a rapid assay of lymphocyte activation and thus new diagnostic tests of cell-mediated immunity, for example to organ transplants and to cancer.  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