全文获取类型
收费全文 | 5676篇 |
免费 | 86篇 |
国内免费 | 10篇 |
专业分类
教育 | 4187篇 |
科学研究 | 334篇 |
各国文化 | 64篇 |
体育 | 536篇 |
综合类 | 3篇 |
文化理论 | 71篇 |
信息传播 | 577篇 |
出版年
2022年 | 28篇 |
2021年 | 70篇 |
2020年 | 99篇 |
2019年 | 164篇 |
2018年 | 207篇 |
2017年 | 216篇 |
2016年 | 207篇 |
2015年 | 134篇 |
2014年 | 159篇 |
2013年 | 1172篇 |
2012年 | 165篇 |
2011年 | 169篇 |
2010年 | 174篇 |
2009年 | 163篇 |
2008年 | 173篇 |
2007年 | 167篇 |
2006年 | 132篇 |
2005年 | 112篇 |
2004年 | 111篇 |
2003年 | 102篇 |
2002年 | 118篇 |
2001年 | 73篇 |
2000年 | 122篇 |
1999年 | 85篇 |
1998年 | 81篇 |
1997年 | 80篇 |
1996年 | 84篇 |
1995年 | 71篇 |
1994年 | 78篇 |
1993年 | 70篇 |
1992年 | 67篇 |
1991年 | 79篇 |
1990年 | 56篇 |
1989年 | 53篇 |
1988年 | 46篇 |
1987年 | 55篇 |
1986年 | 50篇 |
1985年 | 49篇 |
1984年 | 61篇 |
1983年 | 51篇 |
1982年 | 41篇 |
1981年 | 42篇 |
1980年 | 38篇 |
1979年 | 34篇 |
1978年 | 39篇 |
1977年 | 44篇 |
1976年 | 28篇 |
1975年 | 22篇 |
1974年 | 25篇 |
1971年 | 12篇 |
排序方式: 共有5772条查询结果,搜索用时 15 毫秒
1.
Jonathan S. Jones Anna-Lynne R. Adlam Abdelmalek Benattayallah Fraser N. Milton 《Child development》2022,93(3):815-830
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.
Jonathan J. Mallett 《Learned Publishing》2021,34(1):49-56
- Scientific publication has been a key part of the scientific method since the inception of Philosophical Transactions in 1665.
- The scientific publications industry has grown exponentially along with science, incorporating technological innovations along the way, and adapting journal processes and practices to changing needs of science as it matured.
- Of all the technological innovations over more than 300 years, the move to online journals may be the most significant, making open access to content practical for the first time.
- The open‐access movement is disrupting the economics of journal publishing, which is hoped will make the industry more competitive: the ability of the publications industry to adapt to open access will be a measure of its resilience.
- The demand for articles published in reputable journals continues to grow as readers trust the credibility of peer reviewed journal articles, and good authors value the prestige of publishing in the best journals.
- It is difficult to predict what new functionalities may be included in articles of the future or what additional services publishers and editors will provide, but there is every reason to believe that scientific journal articles are here to stay.
3.
Daniel C. Kopala-Sibley Marilyn Cyr Megan C. Finsaas Jonathan Orawe Anna Huang Nim Tottenham Daniel N. Klein 《Child development》2020,91(1):110-128
Seventy-nine 3-year olds and their mothers participated in a laboratory-based task to assess maternal hostility. Mothers also reported their behavioral regulation of their child. Seven years later, functional magnetic resonance imaging data were acquired while viewing emotional faces and completing a reward processing task. Maternal hostility predicted more negative amygdala connectivity during exposure to sad relative to neutral faces with frontal and parietal regions as well as more negative left ventral striatal connectivity during monetary gain relative to loss feedback with the right posterior orbital frontal cortex and right inferior frontal gyrus. In contrast, maternal regulation predicted enhanced cingulo-frontal connectivity during monetary gain relative to loss feedback. Results suggest parenting is associated with alterations in emotion and reward processing circuitry 7–8 years later. 相似文献
4.
5.
Measuring Search Engine Quality 总被引:12,自引:3,他引:9
The effectiveness of twenty public search engines is evaluated using TREC-inspired methods and a set of 54 queries taken from real Web search logs. The World Wide Web is taken as the test collection and a combination of crawler and text retrieval system is evaluated. The engines are compared on a range of measures derivable from binary relevance judgments of the first seven live results returned. Statistical testing reveals a significant difference between engines and high intercorrelations between measures. Surprisingly, given the dynamic nature of the Web and the time elapsed, there is also a high correlation between results of this study and a previous study by Gordon and Pathak. For nearly all engines, there is a gradual decline in precision at increasing cutoff after some initial fluctuation. Performance of the engines as a group is found to be inferior to the group of participants in the TREC-8 Large Web task, although the best engines approach the median of those systems. Shortcomings of current Web search evaluation methodology are identified and recommendations are made for future improvements. In particular, the present study and its predecessors deal with queries which are assumed to derive from a need to find a selection of documents relevant to a topic. By contrast, real Web search reflects a range of other information need types which require different judging and different measures. 相似文献
6.
7.
8.
9.
Peter Davison 《Learned Publishing》2003,16(4):243-247
The Copyright Licensing and Administration Society of Singapore was established in 1999. It is now profitable and commercially significant, perhaps uniquely so in Asia. Critical factors in its growth have included a statutory (non‐voluntary) photocopying licence provision for educational institutions in the Copyright Act; and widespread support from the local and international communities of rightsholders. Tentative consensus has been established with educators over a fair level of remuneration for copying. Further work needs to be done to extend or amend the current model for electronic copying, for the private sector and for other countries in the region. 相似文献
10.