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   2623574篇
  免费   205105篇
  国内免费   4256篇
耳鼻咽喉   37141篇
儿科学   88421篇
妇产科学   73221篇
基础医学   373127篇
口腔科学   74650篇
临床医学   233648篇
内科学   513906篇
皮肤病学   56216篇
神经病学   212514篇
特种医学   104691篇
外国民族医学   1069篇
外科学   398395篇
综合类   60822篇
现状与发展   4篇
一般理论   925篇
预防医学   203094篇
眼科学   59829篇
药学   196221篇
  5篇
中国医学   4833篇
肿瘤学   140203篇
  2018年   26686篇
  2016年   22807篇
  2015年   26143篇
  2014年   36136篇
  2013年   54940篇
  2012年   75192篇
  2011年   79360篇
  2010年   47271篇
  2009年   44902篇
  2008年   75566篇
  2007年   80386篇
  2006年   80932篇
  2005年   78868篇
  2004年   77030篇
  2003年   73731篇
  2002年   72321篇
  2001年   120725篇
  2000年   125072篇
  1999年   106366篇
  1998年   29882篇
  1997年   26974篇
  1996年   27123篇
  1995年   26197篇
  1994年   24651篇
  1993年   23060篇
  1992年   86595篇
  1991年   84430篇
  1990年   82596篇
  1989年   79204篇
  1988年   73491篇
  1987年   72378篇
  1986年   68324篇
  1985年   65938篇
  1984年   49450篇
  1983年   42358篇
  1982年   25008篇
  1981年   22472篇
  1980年   20740篇
  1979年   46279篇
  1978年   32323篇
  1977年   27263篇
  1976年   25631篇
  1975年   27374篇
  1974年   32924篇
  1973年   31733篇
  1972年   29153篇
  1971年   27012篇
  1970年   25139篇
  1969年   23360篇
  1968年   21314篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
992.
Granuloma annulare possibly triggered by antitetanus vaccination   总被引:4,自引:0,他引:4  
We report the case of a 6-year-old girl with granuloma annulare (GA) possibly related to antitetanus vaccinations. The first episode occurred 2 months after the girl had been vaccinated but the lesions were not located at the vaccination site. After 1 year of being free of lesions, she had a second episode unrelated to vaccination. After another 6-month lesion-free period, the girl was administered another antitetanus vaccination and a solitary lesion developed at the vaccination site within 3 days. A few lesions developed on her legs in the 2 months following the appearance of the initial plaque. The literature includes two reports of cases with papular lesions limited to the hepatitis B vaccination site, both histopathologically consistent with necrobiotic granuloma, but clinically not suggestive of GA. To the best of our knowledge, GA following antitetanus vaccination and occurring at the vaccination site has not been reported before. Either the trauma alone from the injection or a vaccine-induced immunological reaction might have triggered the necrobiosis of collagen through some unexplained mechanisms.  相似文献   
993.
994.
Poncet病(病例报告及文献复习)   总被引:4,自引:0,他引:4  
目的 探讨Poncet病的诊断与治疗。方法 通过病例报告及献复习,综述了Poncet病的发病机理、临床表现。结果 提高对Poncet病的认识。结论 临床上对风湿性或类风湿性关节炎病人均应与本病鉴别。  相似文献   
995.
996.
结果 髌股关节的压力与应力随膝关节屈曲角度的增加而升高,随膝关节屈曲角度的减小而降低(图3~8).不同膝关节屈曲角度下弓步变化和跨步变化的髌股关节压力见表1.  相似文献   
997.
998.
999.
BACKGROUND: The recent amalgamation of data by users of the Perinatal Problem Identification Programme (PPIP) throughout South Africa has culminated in the publication of the Saving Babies report. OBJECTIVES: To determine the absolute rate of death from intrapartum-related birth asphyxia, and the contribution of intrapartum-related asphyxia to total perinatal mortality in South African hospitals, and to identify the primary obstetric causes and avoidable factors for these deaths. METHODS: The amalgamated PPIP data for the year 2000 were obtained from 27 state hospitals (6 metropolitan, 12 town and 9 rural) in South Africa. In PPIP-based audit, all perinatal deaths are assigned primary obstetric causes and avoidable factors, and these elements were obtained for all deaths resulting from intrapartum-related birth asphyxia. RESULTS: There were 123,508 births in the hospitals surveyed, with 4,142 perinatal deaths among infants > or = 1,000 g, giving a perinatal mortality rate of 33.5/1,000 births. The perinatal mortality rate from intrapartum-related birth asphyxia was 4.8/1,000 births. The most frequent avoidable factors were delay by mothers in seeking attention during labour (36.6%), signs of fetal distress interpreted incorrectly (24.9%), inadequate fetal monitoring (18.0%) and no response to poor progress in labour (7.0%). The perinatal mortality rates for metropolitan, town, and rural areas were 30.0, 39.4 and 30.9/1,000 births respectively. The contribution of intrapartum-related birth asphyxia to perinatal mortality in these areas was 10.8%, 16.7% and 26.4% respectively. CONCLUSION: The high rates of perinatal death from intrapartum-related birth asphyxia in South Africa are typical of those in underdeveloped countries, with the most serious deficiencies in rural areas. Most of these deaths are avoidable and the reduction of these rates presents an important challenge to providers of perinatal care in this country. Areas worthy of research and action include provision of mothers' waiting facilities in rural regions, improvements in fetal monitoring, partogram-based labour management, and the establishment of midwifery staffing norms for South African labour units.  相似文献   
1000.
Oxidative stress is an important factor in many pathological conditions such as inflammation, cancer, ageing and organ response to ischemia-reperfusion. Humans have developed a complex antioxidant system to eliminate or attenuate oxidative stress. Liver ischemia-reperfusion injury occurs in a number of clinical settings, including liver surgery, transplantation, and hemorrhagic shock with subsequent fluid resuscitation, leading to significant morbidity and mortality. It is characterized by significant oxidative stress but accompanied with depletion of endogenous antioxidants. This review has 2 aims: firstly, to highlight the clinical significance of liver ischemia-reperfusion injury, the underlying mechanisms and the main pathways by which the antioxidants function, and secondly, to describe the new developments that are ongoing in antioxidant therapy and to present the experimental and clinical evidence about the role of antioxidants in modulating hepatic ischemia-reperfusion injury.  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