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   3688篇
  免费   76篇
  国内免费   1篇
教育   2484篇
科学研究   264篇
各国文化   63篇
体育   425篇
综合类   1篇
文化理论   22篇
信息传播   506篇
  2023年   16篇
  2022年   26篇
  2021年   47篇
  2020年   87篇
  2019年   182篇
  2018年   196篇
  2017年   203篇
  2016年   143篇
  2015年   100篇
  2014年   135篇
  2013年   786篇
  2012年   102篇
  2011年   97篇
  2010年   87篇
  2009年   97篇
  2008年   104篇
  2007年   91篇
  2006年   92篇
  2005年   71篇
  2004年   72篇
  2003年   71篇
  2002年   54篇
  2001年   54篇
  2000年   58篇
  1999年   45篇
  1998年   47篇
  1997年   36篇
  1996年   22篇
  1995年   25篇
  1994年   36篇
  1993年   32篇
  1992年   28篇
  1991年   24篇
  1990年   30篇
  1989年   34篇
  1988年   18篇
  1987年   18篇
  1986年   17篇
  1985年   17篇
  1984年   25篇
  1983年   23篇
  1981年   19篇
  1980年   16篇
  1979年   18篇
  1977年   13篇
  1974年   13篇
  1972年   11篇
  1971年   10篇
  1970年   10篇
  1926年   10篇
排序方式: 共有3765条查询结果,搜索用时 15 毫秒
1.
Working memory training improves children's cognitive performance on untrained tasks; however, little is known about the underlying neural mechanisms. This was investigated in 32 typically developing children aged 10–14 years (19 girls and 13 boys) using a randomized controlled design and multi-modal magnetic resonance imaging (Devon, UK; 2015–2016). Training improved working memory performance and increased intrinsic functional connectivity between the bilateral intraparietal sulci. Furthermore, improvements in working memory were associated with greater recruitment of the left middle frontal gyrus on a complex span task. Repeated engagement of fronto-parietal regions during training may increase their activity and functional connectivity over time, affording greater working memory performance. The plausibility of generalizable cognitive benefits from a neurobiological perspective and implications for neurodevelopmental theory are discussed.  相似文献   
2.
Abstract

Carnosine was originally discovered in skeletal muscle, where it exists in larger amounts than in other tissues. The majority of research into the physiological roles of carnosine have been conducted on skeletal muscle. Given this and the potential for muscle carnosine content to be increased with supplementation, there is now a large body of research examining the ergogenic effects (or otherwise) of carnosine. More recent research, however, points towards a potential for carnosine to exert a wider range of physiological effects in other tissues, including the brain, heart, pancreas, kidney and cancer cells. Taken together, this is suggestive of a potential for carnosine to have therapeutic benefits in health and disease, although this is by no means without complication. Herein, we will provide a review of the current literature relating to the potential therapeutic effects of carnosine in health and disease.  相似文献   
3.
4.
5.
As a part of efforts to evaluate and monitor the increasing public investment in early childhood education, teachers are being asked to assess children's school readiness. In this study, preschool teachers and kindergarten teachers rated children's skills in three areas (kindergarten readiness, academic skills, and communication skills), and these ratings were compared with direct assessments of the children's skills. Ratings by both groups of teachers tended to be more highly related to basic skills, such as counting and number naming, than to abilities such as solving applied problems and using expressive and receptive vocabulary. Preschool teachers' ratings had a lower association with children's observed skills and abilities than kindergarten teachers' ratings. Ratings of children attending Head Start were systematically inflated, but this relationship was mediated to a significant extent by the teachers' levels of education. More educated teachers rated children in a manner consistent with the children's directly assessed skills. Implications of these findings for informing future efforts to assess school readiness by using teacher ratings are discussed.  相似文献   
6.
Objective: To determine whether information retrieval might be enhanced by making each component of a structured abstract a separately searchable field. Design: Parallel searches on records arranged so that each abstract could either be searched in its entirety or as a collection of structured fields. Subjects: Records about cardiovascular disease downloaded from MEDLINE and tested against clinical questions derived from a concurrent survey of CD-ROM use in three health science libraries. Intervention: The investigators identified terms used to structure abstracts on MEDLINE and imported the abstracts into an Idealist database prior to searching using keywords from clinical questions. Measurements and main results: recall and precision rates are given for each question in the ‘structured’ and the ‘unstructured’ set of records. Conclusions: Use of structured, rather than unstructured, abstracts improves precision at the ex-pense of recall and places heavier demands upon the searcher’s skill in choosing the correct fields within the abstract to search. Further investigation requires more accurate simulation of MEDLINE software that utilizes features such as MeSH terms, explode, facilities and delimiters.  相似文献   
7.
8.
9.
Higher education in the United Kingdom is centrally funded, centrally planned, and insulated from market forces. It bears many similarities to the non-market centrally planned economies (CPEs) of the former Soviet Union and Eastern Europe while they struggled to reform but to retain a system of planning and central control. Examination of UK higher education and the CPEs before the transformation to market based systems highlights some of the issues facing higher education today. It also highlights the need for reforms, as well as the difficulties involved in them. Such comparison can also bring home problems faced by reformers in the transition economies.
Despite allegedly extensive reforms in UK higher education, the sector faces problems like those facing the centrally planned economies of Eastern Europe and the former USSR in the 1970s and 80s. Parallels in a number of areas are particularly striking.  相似文献   
10.
Design-based research for LIS   总被引:2,自引:0,他引:2  
Design-based research is a methodology emerging from the field of education that may hold potential for research in library and information science (LIS). Based upon the assumption that learning is situated in a real-world context, design-based research combines research, design, and practice into one process. It results in usable products that are supported by a theoretical framework. While definitional and methodological issues do exist, the method holds some promise for research into “user-centered” information systems and services. In the field of LIS, design-based research might contribute to our understanding of how people find, choose, understand, and use information in context. The method is also of interest to professionals concerned with “evidence-based practice.” This article will first explain and describe the method as it has been used in the allied field of education. Issues related to definition and methodology will be explored, as well as some of the solutions that have been proposed. The method will then be related to LIS, using the bonded design work of Large, Nesset, Beheshti, and Bowler [Large, A., Nesset, V., Beheshti, J., & Bowler, L. (2006a). Bonded design: a methodology for designing with children. In S. Kurniawan & P. Saphiris (Eds.), Advances in Universal Web Design and Evaluation: Research, Trends and Opportunities. London: Idea Group., Large, A., Nesset, V., Beheshti, J., & Bowler, L. (2006b). “Bonded design”: a novel approach to intergenerational information technology design. Library and Information Science Research, 28, 64–82] as a case study to demonstrate the applicability of design-based research to LIS inquiry.  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