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   10634篇
  免费   801篇
  国内免费   28篇
耳鼻咽喉   39篇
儿科学   256篇
妇产科学   196篇
基础医学   1807篇
口腔科学   59篇
临床医学   1079篇
内科学   2370篇
皮肤病学   288篇
神经病学   1070篇
特种医学   300篇
外科学   1315篇
综合类   38篇
一般理论   7篇
预防医学   842篇
眼科学   155篇
药学   835篇
中国医学   22篇
肿瘤学   785篇
  2023年   78篇
  2022年   157篇
  2021年   276篇
  2020年   171篇
  2019年   275篇
  2018年   339篇
  2017年   293篇
  2016年   263篇
  2015年   315篇
  2014年   405篇
  2013年   502篇
  2012年   828篇
  2011年   771篇
  2010年   407篇
  2009年   370篇
  2008年   676篇
  2007年   657篇
  2006年   585篇
  2005年   671篇
  2004年   725篇
  2003年   656篇
  2002年   524篇
  2001年   171篇
  2000年   131篇
  1999年   148篇
  1998年   99篇
  1997年   90篇
  1996年   63篇
  1995年   50篇
  1994年   44篇
  1993年   42篇
  1992年   56篇
  1991年   57篇
  1990年   48篇
  1989年   39篇
  1988年   43篇
  1987年   37篇
  1986年   36篇
  1985年   26篇
  1984年   20篇
  1983年   24篇
  1982年   24篇
  1981年   15篇
  1980年   18篇
  1979年   21篇
  1978年   16篇
  1974年   15篇
  1973年   17篇
  1972年   12篇
  1969年   15篇
排序方式: 共有10000条查询结果,搜索用时 78 毫秒
1.
2.
Magnetic resonance elastography aims to non-invasively and remotely characterize the mechanical properties of living tissues. To quantitatively and regionally map the shear viscoelastic moduli in vivo, the technique must achieve proper mechanical excitation throughout the targeted tissues. Although it is straightforward, ante manibus, in close organs such as the liver or the breast, which practitioners clinically palpate already, it is somewhat fortunately highly challenging to trick the natural protective barriers of remote organs such as the brain. So far, mechanical waves have been induced in the latter by shaking the surrounding cranial bones. Here, the skull was circumvented by guiding pressure waves inside the subject's buccal cavity so mechanical waves could propagate from within through the brainstem up to the brain. Repeatable, reproducible and robust displacement fields were recorded in phantoms and in vivo by magnetic resonance elastography with guided pressure waves such that quantitative mechanical outcomes were extracted in the human brain.  相似文献   
3.
4.
5.
6.
Postpartum fatigue is a normal condition that most women experience. Breastfeeding is often associated in women's minds as contributing to the feeling of overall perceived fatigue, and many women indicate that they have ceased breastfeeding because of fatigue. However, the relationship between feeding choice and perceived fatigue has never been established. Two hundred and fifty-three women participated in a study examining whether perceived fatigue differed for bottle-feeding and breastfeeding women at 3 different times during the postpartum period (2-4 days, 6 weeks, and 12 weeks postpartum). Results showed no significant differences for these 2 groups, suggesting that perceived fatigue during the postpartum period is not dependent on feeding choice. Additional analyses examining other variables with a potential effect were nonsignificant. Because perceived physical fatigue does not appear to be dependent on feeding choice, women should be prepared for the feeling of perceived fatigue during the postpartum period while at the same time be reassured that feeding choice is not correlated.  相似文献   
7.
The polymorphism at the HLA-DPB1 locus has been characterized in a large number of patients with multiple sclerosis (n = 112) and in healthy controls (n = 115). Both patients and controls lived in the southwest of France (in the Pyrénées Atlantiques) and had similar ethnic background. The typing procedure involved the selective amplification of the second exon of the DPB1 locus by polymerase chain reaction, followed by hybridization of the amplified DNA with 14 sequence-specific oligonucleotide probes. Individual alleles were identified by the pattern of hybridization of the different probes. The distribution of the DPB1 alleles was not significantly different in multiple sclerosis patients and controls (p = 0.11). This does not corroborate the reported association of multiple sclerosis with the primed lymphocyte typing (PLT)-defined DPw4 specificity and is not in favour of a role played by polymorphic residues of the DP molecule in susceptibility to multiple sclerosis.  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