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   3015219篇
  免费   237999篇
  国内免费   6120篇
耳鼻咽喉   43049篇
儿科学   95874篇
妇产科学   81790篇
基础医学   427181篇
口腔科学   87087篇
临床医学   275939篇
内科学   584501篇
皮肤病学   63737篇
神经病学   250336篇
特种医学   119332篇
外国民族医学   1131篇
外科学   453683篇
综合类   72445篇
现状与发展   1篇
一般理论   1287篇
预防医学   244330篇
眼科学   71166篇
药学   223268篇
  61篇
中国医学   5731篇
肿瘤学   157409篇
  2018年   31145篇
  2016年   26776篇
  2015年   30116篇
  2014年   43061篇
  2013年   65864篇
  2012年   88105篇
  2011年   93093篇
  2010年   55207篇
  2009年   52583篇
  2008年   88077篇
  2007年   93714篇
  2006年   94739篇
  2005年   92030篇
  2004年   89023篇
  2003年   85814篇
  2002年   84103篇
  2001年   137846篇
  2000年   142645篇
  1999年   120396篇
  1998年   35043篇
  1997年   31785篇
  1996年   31412篇
  1995年   30451篇
  1994年   28594篇
  1993年   26558篇
  1992年   97328篇
  1991年   94354篇
  1990年   91429篇
  1989年   88147篇
  1988年   81439篇
  1987年   80592篇
  1986年   76168篇
  1985年   72992篇
  1984年   55348篇
  1983年   47217篇
  1982年   28810篇
  1981年   25682篇
  1980年   24057篇
  1979年   52020篇
  1978年   36759篇
  1977年   31081篇
  1976年   29307篇
  1975年   30778篇
  1974年   37922篇
  1973年   36088篇
  1972年   33673篇
  1971年   31269篇
  1970年   29222篇
  1969年   27236篇
  1968年   24885篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
31.
BACKGROUND: Radioiodine therapy (RIT) combined with glucocorticoids is an effective therapy for Graves' disease, but it is debatable whether glucocorticoids should be applied in patients without Graves' ophthalmopathy (GO). METHODS: The effect of 0.4 - 0.5 mg prednisone every second day over a period of 5 weeks after RIT was monitored over a follow-up period of at least 12 months after RIT. A questionnaire was sent to 186 consecutive patients without GO concerning eye symptoms after RIT. 148 patients (80 %) answered. If eye symptoms had occurred after RIT, additional clinical examination was carried out at our outpatient clinic. The primary endpoint was the absence or onset of GO within the first year after RIT. RESULTS: Within 12 months after RIT the examination confirmed GO in 5 out of 148 patients (3.4 %). In all cases the symptoms were transient. No adverse reaction to the use of prednisone after RIT was noted. CONCLUSIONS: The risk of new GO in the first year after RIT was low and the clinical course of GO was mild when RIT was combined with a low-dose glucocorticoid regimen. Preventive administration of glucocorticoids can therefore be recommended in patients with Graves' disease even without evident GO.  相似文献   
32.
The present study compared four different sites and conditions for the measurement of maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) in 38 spontaneous breathing tracheotomised patients. Of the patients, 28 had chronic obstructive pulmonary disease (COPD). The four different conditions were: 1) through a cuff inflated cannula (condition A); 2) through the mouth with a deflated cannula (condition B); 3) through the mouth with a phonetic uncuffed cannula (condition C); and 4) through the mouth after stoma closure (condition D). Five trials in each condition were performed using a standardised method. The measurement of both MIP and MEP differed significantly depending on the condition of measurement. MIP taken in condition A was significantly higher when compared with conditions B, C and D. MEP in condition A was significantly higher when compared with condition B and D. In condition A the highest frequency of the best measurement of MIP and MEP was observed at the fourth and fifth effort, respectively. The same results were obtained after the selection of only COPD patients. In conclusion, respiratory muscle assessment differs significantly depending on measurement condition. Measurement through inflated cannula tracheotomy yields higher values of both maximal inspiratory and maximal expiratory pressure.  相似文献   
33.
Chronic obstructive pulmonary disease (COPD) is characterised by a local pulmonary inflammatory response to respiratory pollutants and by systemic inflammation. Tumour necrosis factor (TNF)-alpha has been implicated in systemic effects of COPD and operates by binding the p55 (R1) and p75 (R2) TNF-alpha receptors. To investigate the contribution of each TNF-alpha receptor in the pathogenesis of COPD, the present study examined the effects of chronic air or cigarette smoke (CS) exposure in TNF-alpha R1 knockout (KO) mice, TNF-alpha R2 KO mice and wild type (WT) mice. CS was found to significantly increase the protein levels of soluble TNF-alpha R1 (by four-fold) and TNF-alpha R2 (by 10-fold) in the bronchoalveolar lavage of WT mice. After 3 months, CS induced a prominent pulmonary inflammatory cell influx in WT and TNF-alpha R1 KO mice. In TNF-alpha R2 KO mice, CS-induced pulmonary inflammation was clearly attenuated. After 6 months, no emphysema was observed in CS-exposed TNF-alpha R2 KO mice in contrast to WT and TNF-alpha R1 KO mice. CS-exposed WT and TNF-alpha R1 KO mice failed to gain weight, whereas the body mass of TNF-alpha R2 KO mice was not affected. These current findings suggest that both tumour necrosis factor-alpha receptors contribute to the pathogenesis of chronic obstructive pulmonary disease, but tumour necrosis factor-alpha receptor-2 is the most active receptor in the development of inflammation, emphysema and systemic weight loss in this murine model of chronic obstructive pulmonary disease.  相似文献   
34.
35.
36.
Summary: A female patient with isovaleric acidaemia had a successful outcome from pregnancy.  相似文献   
37.
38.
39.
40.
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