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   1526篇
  免费   146篇
  国内免费   21篇
耳鼻咽喉   3篇
儿科学   93篇
妇产科学   10篇
基础医学   191篇
口腔科学   71篇
临床医学   201篇
内科学   277篇
皮肤病学   54篇
神经病学   51篇
特种医学   256篇
外科学   146篇
综合类   72篇
预防医学   120篇
眼科学   15篇
药学   51篇
  1篇
肿瘤学   81篇
  2023年   6篇
  2022年   5篇
  2021年   11篇
  2020年   13篇
  2019年   16篇
  2018年   30篇
  2017年   18篇
  2016年   27篇
  2015年   35篇
  2014年   44篇
  2013年   65篇
  2012年   44篇
  2011年   41篇
  2010年   69篇
  2009年   65篇
  2008年   35篇
  2007年   61篇
  2006年   37篇
  2005年   35篇
  2004年   37篇
  2003年   48篇
  2002年   35篇
  2001年   34篇
  2000年   27篇
  1999年   38篇
  1998年   85篇
  1997年   81篇
  1996年   63篇
  1995年   55篇
  1994年   41篇
  1993年   49篇
  1992年   16篇
  1991年   35篇
  1990年   25篇
  1989年   56篇
  1988年   53篇
  1987年   44篇
  1986年   33篇
  1985年   27篇
  1984年   18篇
  1983年   14篇
  1982年   18篇
  1981年   17篇
  1980年   16篇
  1979年   10篇
  1978年   14篇
  1977年   11篇
  1976年   11篇
  1975年   11篇
  1973年   4篇
排序方式: 共有1693条查询结果,搜索用时 15 毫秒
1.
Dimerization of human immunodeficiency virus type 1 protease (HIV-1 PR) monomers is an essential prerequisite for viral proteolytic activity and the subsequent generation of infectious virus particles. Disruption of the dimer interface inhibits this activity as does formation of heterodimers between wild-type and defective monomers. A structure-based approach was used to identify amino acid substitutions at the dimer interface of HIV-1 PR that facilitate preferential association of heterodimers and inhibit self-association of the defective monomers. Expression of the designed PR monomers inhibits activity of wild-type HIV-1 PR and viral infectivity when assayed in an ex vivo model system. These results show that it is possible to design PR monomers as macromolecular inhibitors that may provide an alternative to small molecule inhibitors for the treatment of HIV infection.  相似文献   
2.
The ravelled sleeve of care. Managing the stresses of residency training   总被引:4,自引:0,他引:4  
J M Colford  S J McPhee 《JAMA》1989,261(6):889-893
  相似文献   
3.
4.
5.
Pyomyositis: characteristics at CT and MR imaging   总被引:9,自引:0,他引:9  
Gordon  BA; Martinez  S; Collins  AJ 《Radiology》1995,197(1):279
  相似文献   
6.
SUMMARY A case is reported of pseudohyperphosphataemia in association with a monoclonal gammopathy of undetermined significance.  相似文献   
7.
8.
BACKGROUND: Diagnosis of atopic dermatitis (AD) depends on clinical features because no definitive diagnostic test exists. Criteria proposed by Hanifin and Rajka (Acta Derm Venereol (Stockh) 1980; Suppl 92: 44-47) were acceptable for hospital-based studies but were found not to be suitable for field studies. A UK working party formulated clinical diagnostic criteria that could be used in both hospital and epidemiological settings. Validation studies of the criteria showed widely variable results, probably due to different clinical settings and ethnicity. AIM AND OBJECTIVE: This study was undertaken to validate Hanifin and Rajka's criteria and to assess the comparative efficacy of their criteria and the UK working party's diagnostic criteria in the diagnosis of AD in a hospital setting in North India. SUBJECTS AND METHODS: This study serially included 101 patients with AD and 48 controls of paediatric age group. The study period was from July 2003 to December 2004. RESULTS: Hanifin and Rajka's criteria (sensitivity 96%, specificity 93.75%, positive predictive value 97% (PPV) and negative predictive value (NPV) 91.84%) had a statistical advantage over the UK working party's diagnostic criteria (sensitivity 86%, specificity 95.83%, PPV 97.75% and NPV 76.67%), with a P-value < 0.005.  相似文献   
9.
SUMMARY Impotence is a common symptom which can cause considerable distress to both the sufferer and his partner. The use of pharmacotherapy to improve erectile function will continue to increase as safe and effective drugs are developed. However, restoring erectile function should not be the only treatment objective. It is also essential to address personal and emotional factors in the sufferer, conflicts in his relationship with his partner, and sexual problems in his partner, all of which may be instrumental in causing or maintaining the presenting impotence. We advocate a combined approach with appropriate medical treatment and sex and couple therapy  相似文献   
10.
Acute appendicitis: CT and US correlation in 100 patients   总被引:19,自引:1,他引:18  
  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