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   12983篇
  免费   131篇
  国内免费   4篇
教育   8985篇
科学研究   1721篇
各国文化   84篇
体育   741篇
综合类   10篇
文化理论   163篇
信息传播   1414篇
  2021年   86篇
  2020年   105篇
  2019年   187篇
  2018年   908篇
  2017年   902篇
  2016年   676篇
  2015年   197篇
  2014年   206篇
  2013年   1707篇
  2012年   267篇
  2011年   488篇
  2010年   465篇
  2009年   296篇
  2008年   383篇
  2007年   460篇
  2006年   152篇
  2005年   206篇
  2004年   298篇
  2003年   204篇
  2002年   144篇
  2001年   147篇
  2000年   177篇
  1999年   156篇
  1998年   89篇
  1997年   98篇
  1996年   98篇
  1995年   75篇
  1994年   65篇
  1993年   100篇
  1992年   126篇
  1991年   144篇
  1990年   153篇
  1989年   126篇
  1988年   114篇
  1987年   122篇
  1986年   123篇
  1985年   137篇
  1984年   120篇
  1983年   122篇
  1982年   121篇
  1981年   97篇
  1980年   92篇
  1979年   123篇
  1978年   117篇
  1977年   101篇
  1976年   91篇
  1975年   66篇
  1974年   83篇
  1973年   74篇
  1971年   74篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Editorial     
B. Sury 《Resonance》2018,23(7):723-725
  相似文献   
2.
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   
3.
4.
5.
A significant number of archaeological finds of the 13th–16th century from the Tuscan sites of Germagnana and Gambassi in Valdelsa—FI, was studied by different physico-chemical investigations (SEM–EDS, ICP, Mössbauer spectroscopy, XRD, XRF, TG-DTA) in order to contribute to clarify the production methodology and the pre-industrial glass manufacture technology. The studied samples are mainly non-vitreous finds as production waste, refractory materials, crucibles and raw materials; also vitreous finds as frits, skims, glasses (glass masses, glass working waste and finished products) have been taken into consideration. The obtained petrographic and physico-chemical data strongly suggest that both Gambassi and Germagnana glass manufactures were strictly connected with the sources of vitrifiable materials, situated in Tuscan sand quarries. In particular a comparison between sands from the neighbouring quarries and appropriate finds of the two archaeological sites evidences that the employed vitrifiable materials possibly belong to La Casina La Cava resort. The archaeological classification, based on macroscopic observation and stratigraphic position, was compared and verified with the scientific classification of the examined finds of Germagnana and Gambassi sites based on their composition, morphology and physico-chemical properties.  相似文献   
6.
7.
8.
9.
The aim of this study was to investigate the effects of extensive endurance training (15-25 h per week) on the development of maximal oxygen uptake (VO2 max) in boys from puberty. Maximal oxygen uptake was measured a number of times each year from the age of puberty and for the next 6-9 years in seven young male elite cross-country skiers. Mean VO2 max was measured as 76.3 and 80.1 ml kg-1 min-1 at the ages of 14 and 15 years respectively. Despite the fast rate of growth during puberty, maximal aerobic power showed seasonal variations from the age of 14, reaching a plateau at the age of 15, whereas VO2 max (ml kg-2/3 min-1) increased continuously. It is concluded that, during puberty, boys probably attain significant increases in VO2 max when appropriate amounts of endurance training are undertaken.  相似文献   
10.
教练员与运动员关系的研究   总被引:7,自引:0,他引:7  
我国竞技体育,教练员与运动员关系好的不乏其人,他们努力训练,通力合作,为我国的竞技体育的腾飞作出了卓越的贡献,但也有些教练员与运动员关系不融洽,使运动员过早地离开运动场,失去了为国争光的机会。文章通过教练员和运动员关系的研究,旨在为提高竞技运动水平和教练员在选材、训练时提供参考。  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