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   24409篇
  免费   1976篇
  国内免费   61篇
耳鼻咽喉   247篇
儿科学   859篇
妇产科学   623篇
基础医学   3285篇
口腔科学   407篇
临床医学   3325篇
内科学   4589篇
皮肤病学   325篇
神经病学   2638篇
特种医学   581篇
外国民族医学   2篇
外科学   2308篇
综合类   303篇
一般理论   38篇
预防医学   3207篇
眼科学   478篇
药学   1354篇
中国医学   20篇
肿瘤学   1857篇
  2023年   165篇
  2022年   247篇
  2021年   570篇
  2020年   312篇
  2019年   599篇
  2018年   687篇
  2017年   507篇
  2016年   517篇
  2015年   622篇
  2014年   799篇
  2013年   1205篇
  2012年   1568篇
  2011年   1641篇
  2010年   942篇
  2009年   783篇
  2008年   1425篇
  2007年   1526篇
  2006年   1549篇
  2005年   1451篇
  2004年   1267篇
  2003年   1215篇
  2002年   1246篇
  2001年   316篇
  2000年   319篇
  1999年   317篇
  1998年   276篇
  1997年   227篇
  1996年   191篇
  1995年   172篇
  1994年   178篇
  1993年   167篇
  1992年   227篇
  1991年   222篇
  1990年   203篇
  1989年   204篇
  1988年   186篇
  1987年   157篇
  1986年   185篇
  1985年   148篇
  1984年   149篇
  1983年   123篇
  1982年   120篇
  1981年   98篇
  1980年   113篇
  1979年   95篇
  1978年   86篇
  1977年   85篇
  1976年   75篇
  1975年   73篇
  1973年   88篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
Maternal and Child Health Journal - Early life exposures can have an impact on a child’s developmental trajectory and children born late preterm (34–36 weeks gestational age)...  相似文献   
2.
3.
Ana Lopez Alonso 《Platelets》2015,26(4):317-323
Abstract

While the interactions between Gram-positive bacteria and platelets have been well characterized, there is a paucity of data on the interaction between other pathogens and platelets. However, thrombocytopenia is a common feature with many infections especially viral hemorrhagic fever. The little available data on these interactions indicate a similarity with bacteria-platelet interactions with receptors such as FcγRIIa and Toll-Like Receptors (TLR) playing key roles with many pathogens. This review summarizes the known interactions between platelets and pathogens such as viruses, fungi and parasites.  相似文献   
4.
5.
6.
In the United States, renal cell carcinoma (RCC) incidence and the prevalence of obesity, an established risk factor for RCC, have been increasing for several decades. RCC is more common among older individuals. We sought to quantify the contribution of excess adiposity to the rising incidence of RCC among individuals 60 years or older. National Institutes of Health-American Association of Retired Persons Diet and Health Study data (n = 453 859 participants, enrolled in 1995-1996, age at enrollment 50-71 years) were used to estimate multivariable-adjusted hazard ratios (HRs) for RCC across body mass index categories and HRs associated with smoking. Population attributable fractions (PAFs) were calculated using estimated HRs and annual overweight/obesity prevalence from the National Health Interview Survey (1985-2008). PAF estimates were combined with RCC incidence from Surveillance, Epidemiology and End Results-13 to calculate annual percent changes in RCC incidence attributable (and unrelated) to overweight/obesity. We found that between 1995 and 2018, among individuals aged 60 years and older, PAF for overweight/obesity increased from 18% to 29% for all RCCs. In comparison, the PAF for smoking declined from 12% to 9%. RCC incidence increased 1.8% per year (95% confidence interval [CI] 1.5%-2.1%) overall, while RCC incidence attributable to overweight/obesity increased 3.8% per year (95%CI 3.5%-4.2%) and RCC incidence unrelated to overweight/obesity increased 1.2% per year (95% CI 0.9%-1.4%). In conclusion, overweight/obesity appears to have contributed importantly to the rising incidence of RCC in the United States since the mid-1990s. Public health interventions focused on reducing overweight and obesity could help substantially in curbing this trend.  相似文献   
7.
In the work described here, our aim was to determine, in an elderly population, changes in muscle thickness (MT), cross-sectional area (CSA) and echo intensity (EI) of the quadriceps muscles at four time points (0, 5, 10 and 15 min; i.e., T0, T5, T10 and T15, respectively) after changing from a standing to supine position. Twenty-one elderly participants (14 men: 68.1 ± 4.6 y; 8 women: 66.8 ± 4.1 y) were evaluated at four time points. Rectus femoris CSA (RFCSA), MT and EI of the quadriceps femoris (QF) muscles were assessed. EI significantly increased from T0 to T5, T10 and T15 (p < 0.001), whereas no differences were observed between T5 and T15 in the rectus femoris (RFEI), vastus intermedius (VIEI) and quadriceps femoris (QFEI). No differences were observed between any time points in the RFCSA and MT of QF muscles. In summary, these results suggest that periods >5 min are not necessary to obtain consistent MT and EI measurements of quadriceps femoris muscles in the elderly population.  相似文献   
8.
9.
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