全文获取类型
收费全文 | 2249篇 |
免费 | 34篇 |
专业分类
教育 | 1653篇 |
科学研究 | 151篇 |
各国文化 | 15篇 |
体育 | 238篇 |
文化理论 | 15篇 |
信息传播 | 211篇 |
出版年
2022年 | 14篇 |
2021年 | 16篇 |
2020年 | 44篇 |
2019年 | 82篇 |
2018年 | 82篇 |
2017年 | 81篇 |
2016年 | 64篇 |
2015年 | 47篇 |
2014年 | 60篇 |
2013年 | 492篇 |
2012年 | 45篇 |
2011年 | 50篇 |
2010年 | 29篇 |
2009年 | 41篇 |
2008年 | 47篇 |
2007年 | 44篇 |
2006年 | 50篇 |
2005年 | 36篇 |
2004年 | 46篇 |
2003年 | 32篇 |
2002年 | 33篇 |
2001年 | 29篇 |
2000年 | 47篇 |
1999年 | 33篇 |
1998年 | 25篇 |
1997年 | 31篇 |
1996年 | 18篇 |
1995年 | 21篇 |
1994年 | 30篇 |
1993年 | 27篇 |
1992年 | 25篇 |
1991年 | 26篇 |
1990年 | 27篇 |
1989年 | 33篇 |
1988年 | 20篇 |
1987年 | 16篇 |
1986年 | 20篇 |
1985年 | 26篇 |
1984年 | 28篇 |
1983年 | 20篇 |
1982年 | 16篇 |
1981年 | 20篇 |
1980年 | 21篇 |
1979年 | 24篇 |
1978年 | 16篇 |
1977年 | 14篇 |
1973年 | 14篇 |
1972年 | 11篇 |
1971年 | 11篇 |
1970年 | 11篇 |
排序方式: 共有2283条查询结果,搜索用时 46 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.
Guilherme Giannini Artioli Craig Sale Rebecca Louise Jones 《European Journal of Sport Science》2019,19(1):30-39
AbstractCarnosine 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.
6.
7.
One of the highest priorities in today's hospitals is the provision of quality care to patients. The medical librarian has an increased responsibility to furnish quality information to the medical staff. Traditional methods of reference service continue to work well, but it is increasingly important for librarians to become more directly involved in hospital quality assurance (QA) activities. Occurrence screening is one system of QA where the librarian can make a difference. 相似文献
8.
Analysis of the urban/rural broadband divide in Canada: Using GIS in planning terrestrial wireless deployment 总被引:3,自引:0,他引:3
M. Sawada Daniel Cossette Barry Wellar Tolga Kurt 《Government Information Quarterly》2006,23(3-4):454
Millions of Canadians residing in Canada's northern, isolated, rural, and remote communities do not have broadband Internet access. This situation has led to a national “broadband divide.” That is, the deployment of wireline broadband is very limited in Canada's northern, isolated, rural, and remote areas because of the significant expense of installation and maintenance of the wired infrastructure needed to reach dwellings in these locations.Terrestrial broadband wireless technology, on the other hand, does not entail the same kind of physical infrastructure. As a result, there are dramatic changes in how spatial considerations affect the provision of broadband Internet services (BIS) to areas beyond the urban zone. In particular, the spatial question is now focused on assessing the capacity for different technological solutions to reach profitable population bases, and brings to the forefront organizations that are developing non-line-of-sight (NLOS) technologies that would permit wireless Internet access over much greater distances than current solutions.We begin this paper by establishing the importance of broadband connectivity to Canada's northern, isolated, rural, and remote communities. This discussion comments on the role of the Government of Canada in the provision of broadband connectivity to residents of these communities, and outlines the current regulatory issues that govern wireless services and policy formulation.The second part of the paper illustrates the use of geographic information system (GIS) approaches in the study of wireless broadband planning and deployment. Case study findings suggest that GIS applications can make a significant contribution to the analysis of wireless deployment planning, to the understanding of the relationships between wireless signal sources and consumers, and to the spatial configuration of terrestrial wireless broadband networks. We conclude the paper by discussing how the GIS approach employed could be used to inform the public policy process with regard to increasing access to broadband Internet services in all regions of the country, and thereby providing the opportunity for all Canadians, regardless of location, to fully participate in the Information Society. 相似文献
9.
Karyn Ogata Jones Bryan E. Denham Jeffrey K. Springston 《Journal of Applied Communication Research》2006,34(1):94-113
Drawing on components of agenda-setting theory and the two-step flow of information from mass media to news audiences, this study examines the effects of mass and interpersonal communication on breast cancer screening practices among college- and middle-aged women (n = 284). We theorized that screening behaviors among younger women would be influenced more by interpersonal sources of information while screening among middle-aged women would be more influenced by exposure to mass-mediated information. Findings supported anticipated patterns, revealing important and varying roles for both mass and interpersonal communication in the health behaviors of women. Implications for health practitioners and campaign planners, as well as recommendations for future research, are discussed. 相似文献
10.
Anonymous personalization in collaborative web search 总被引:2,自引:0,他引:2
We present an innovative approach to Web search, called collaborative search, that seeks to cope with the type of vague queries that are commonplace in Web search. We do this by leveraging the search
behaviour of previous searchers to personalize future result-lists according to the implied preferences of a community of
like-minded individuals. This technique is implemented in the I-SPY meta-search engine and we present the results of a live-user
trial which indicates that I-SPY can offer improved search performance when compared to a benchmark search engine, across
a variety of performance metrics. In addition, I-SPY achieves its level of personalization while preserving the anonymity
of individual users, and we argue that this offers unique privacy benefits compared to alternative approaches to personalization. 相似文献