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   116394篇
  免费   1851篇
  国内免费   234篇
教育   80321篇
科学研究   13205篇
各国文化   1972篇
体育   9181篇
综合类   171篇
文化理论   1051篇
信息传播   12578篇
  2021年   917篇
  2020年   1638篇
  2019年   2532篇
  2018年   2996篇
  2017年   3274篇
  2016年   3333篇
  2015年   2290篇
  2014年   3158篇
  2013年   27188篇
  2012年   2312篇
  2011年   2626篇
  2010年   2293篇
  2009年   2594篇
  2008年   2324篇
  2007年   2035篇
  2006年   2297篇
  2005年   2287篇
  2004年   2979篇
  2003年   2291篇
  2002年   2109篇
  2001年   1973篇
  2000年   1633篇
  1999年   1532篇
  1998年   1353篇
  1997年   1344篇
  1996年   1537篇
  1995年   1346篇
  1994年   1339篇
  1993年   1335篇
  1992年   1342篇
  1991年   1243篇
  1990年   1270篇
  1989年   1169篇
  1988年   1030篇
  1987年   951篇
  1986年   992篇
  1985年   1223篇
  1984年   1132篇
  1983年   1058篇
  1982年   1068篇
  1981年   996篇
  1980年   959篇
  1979年   1064篇
  1978年   1032篇
  1977年   948篇
  1976年   853篇
  1975年   691篇
  1974年   694篇
  1973年   666篇
  1972年   504篇
排序方式: 共有10000条查询结果,搜索用时 62 毫秒
11.
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   
12.
13.
14.
15.
ABSTRACT

Full three-dimensional movements and external moments in golfers’ knees and the possible involvement in injuries have not been evaluated using motion capture at high sample frequencies. This study measured joint angles and external moments around the three anatomical axes in both knees of 10 professional golfers performing golf drives whilst standing on two force plates in a motion capture laboratory. Significant differences were found in the knee joint moments between the lead and trail limbs for the peak values and throughout all stages during the swing phase. A significantly higher net abduction moment impulse was seen in the trail limb compared with the lead limb (?0.518 vs. ?0.135 Nms.kg?1), indicating greater loading over the whole swing, which could contribute to knee lateral compartment or anterior cruciate ligament injuries. A significant correlation (= ?0.85) between clubhead speed at ball contact and maximum joint moment was found, with the largest correlations being found for joint moments at the top of the backswing event and at the end of the follow-through. Therefore, although knee moments can contribute to high clubhead speeds, the large moments and impulses suggest that they may also contribute to chronic knee injuries or exacerbate existing conditions.  相似文献   
16.
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   
17.
Ronald Barnett's modern classic Realizing the University in an Age of Supercomplexity (published December 1999), has had a crucial impact internationally on the field of Higher Education research and development since the book was published now nearly 20 years ago. Bridging an academic oeuvre across almost 30 years with close to 30 published volumes, Realizing the University in an Age of Supercomplexity plays an important role in the development and transformation of Barnett's social theory of Higher Education into a social philosophy of Higher Education. In the book Barnett performs an important move from a focus on knowledge and epistemology to a focus on being and ontology in relation to Higher Education practices. Barnett shifts his fundamental perspective and view on the relation between universities and the wider society from one of caution and worry to a perspective of hope and vision that fully embraces the future of Higher Education. This way, Realizing the University in an Age of Supercomplexity has not only paved the way for Barnett's own development of a social philosophy of Higher Education, but also contributed invaluably to the rise and maturing of philosophy of Higher Education as a research field in its own right.  相似文献   
18.
Editorial     
B. Sury 《Resonance》2018,23(7):723-725
  相似文献   
19.
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   
20.
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   
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