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   36129篇
  免费   549篇
  国内免费   37篇
教育   26161篇
科学研究   3355篇
各国文化   280篇
体育   2643篇
综合类   41篇
文化理论   341篇
信息传播   3894篇
  2021年   319篇
  2020年   489篇
  2019年   706篇
  2018年   1502篇
  2017年   1600篇
  2016年   1328篇
  2015年   626篇
  2014年   819篇
  2013年   6503篇
  2012年   859篇
  2011年   1178篇
  2010年   914篇
  2009年   761篇
  2008年   957篇
  2007年   937篇
  2006年   714篇
  2005年   608篇
  2004年   640篇
  2003年   539篇
  2002年   591篇
  2001年   686篇
  2000年   644篇
  1999年   613篇
  1998年   324篇
  1997年   357篇
  1996年   377篇
  1995年   343篇
  1994年   314篇
  1993年   315篇
  1992年   473篇
  1991年   444篇
  1990年   485篇
  1989年   480篇
  1988年   452篇
  1987年   380篇
  1986年   392篇
  1985年   460篇
  1984年   388篇
  1983年   398篇
  1982年   296篇
  1981年   292篇
  1980年   267篇
  1979年   406篇
  1978年   314篇
  1977年   300篇
  1976年   257篇
  1975年   226篇
  1974年   207篇
  1973年   238篇
  1971年   169篇
排序方式: 共有10000条查询结果,搜索用时 234 毫秒
1.
Purpose: Overuse injuries are common in sport, but complete understanding of injury risk factors remains incomplete. Although biomechanical studies frequently examine musculoskeletal injury mechanisms, human movement variability studies aim to better understand neuromotor functioning, with proposed connections between overuse injury mechanisms and changes in motor variability. Method: In a narrative review, we discuss the variability-overuse injury hypothesis, which suggests repeated load application leads to mechanical tissue breakdown and subsequent injury when exceeding the rate of physiological adaptation. Due to the multidisciplinary nature of this hypothesis, we incorporate concepts from motor control, neurophysiology, biomechanics, as well as research design and data analysis. We therefore summarize multiple perspectives while proposing theoretical relationships between movement variability and lower extremity overuse injuries. Results: Experimental data are presented and summarized from published experiments examining interactions between experimental task demands and movement variability in the context of drop landing movements, along with comparisons to previous movement variability studies. Conclusion: We provide a conceptual framework for sports medicine researchers interested in predicting and preventing sports injuries. Under performance conditions with greater task demands, we predict reduced trial-to-trial movement variability that could increase the likelihood of overuse injuries.  相似文献   
2.
Research in Higher Education - State financial aid grant programs are commonly categorized as either need-based, merit-based, or both, but their initial eligibility requirements include many more...  相似文献   
3.
Editorial     
B. Sury 《Resonance》2018,23(7):723-725
  相似文献   
4.
Genetic variation in the angiotensin II type 1 receptor (AT1R) has an important effect on the outcome of acute coronary syndrome (ACS) initiated treatment with captopril. This study aims to investigate the impact of genetic polymorphism of AT1R (rs5186 and rs275651) on the ACS outcome in Iraqi patients treated with captopril. A total of 250 Iraqi individuals with ACS were included in this case—control study and they were divided into two study groups; Study group 1 included 125 participants who were prescribed captopril, 25 mg twice daily and study group 2 included 125 participants who received no captopril as part of their ACS treatment (control study). The AT1R gene (rs5186) CC genotype was found to be associated with ST-elevation myocardial infarction (STEMI) (Odd’s ratio (O.R) = 1.2, P = 0.7), while AC was associated with Non-ST-elevation myocardial infarction (NSTEMI) and unstable angina (UA) (O.R = 1.2, P = 0.8). AC genotype is more prone to have Percutaneous coronary intervention (PCI) after ACS attack (O.R = 1.2, P = 0.6). CC genotype had a risk to get less improvement (O.R = 1.6, P = 0.5), so might require higher doses of captopril during acute coronary insult. The AT1R gene (rs275651) AA genotype was associated with UA (O.R = 1.3, P = 0.9). AA and AT genotypes were more prone to have PCI after ACS attack (O.R = 3.9 P = 0.2, O.R = 3.5, P = 0.3 respectively) and thus requiring higher doses of captopril. We conclude that the AT1R rs5186, rs275651 genetic polymorphisms might partially affect the clinical outcome of ACS patients treated with captopril and might have captopril resistance which requires higher doses.  相似文献   
5.
ABSTRACT

For many forcefully displaced people worldwide, notions around one’s sense of “home” and “place” in the world are perpetually unsettled. This article explores how digital technologies interact with embodied, material experiences within the geographical location refugees are residing in. Empirical examples from ethnographic research conducted among Iraqi urban refugees, living in prolonged uncertainty in Jordan, shows how situated experiences of legal, material, and social uncertainty reinforce particular mediated socialities. Pivotal studies have shown how digital connections engender virtual home-making practices and a wide variety of connected presences. This study points to the other side of the same coin: the cultivation of “absent presence.” “Absent presence” refers to feelings—the ambivalence that experiences of prolonged displacement bring about—but also to active disengagement and affective tactics in response. These engender a further separation from the physical world where forced migrants are not deemed welcome.  相似文献   
6.
7.
8.
The emerging creative practices of digital collections are increasing in prominence thanks to the access to, and appeal of, data visualizations. Interactive data visualizations, such as a map, timeline, chart, graph, or artist’s rendering of data, enable users to pursue their own research interests within a collection and participate in new areas of research. Use of these data visualizations enhances the scope of the collection and enables a modern and diverse thematic collection to emerge. This article considers the question: Does the addition of data visualizations affect how users participate with a research collection? Impacts on collection development, application of user-centered design, and analysis of users’ exploratory strategies are discussed. Examples of data visualizations used in digital humanities projects and digital collections are presented as case studies.  相似文献   
9.
Children are sensitive to a number of considerations influencing distributions of resources, including equality, equity, and reciprocity. We tested whether children use a specific type of reciprocity norm—market norms—in which resources are distributed differentially based strictly on amount offered in return. In two studies, 195 children 5–10 years and 60 adults distributed stickers to friends offering same or different amounts of money. Overall, participants distributed more equally when offers were the same and more unequally when offers were different. Although sensitive to why friends offered different amounts of money, children increasingly incorporated market norms into their distributions with age, as the oldest children and adults distributed more to those offering more, irrespective of the reasons provided.  相似文献   
10.
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