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   2829篇
  免费   211篇
  国内免费   60篇
耳鼻咽喉   28篇
儿科学   36篇
妇产科学   39篇
基础医学   285篇
口腔科学   114篇
临床医学   250篇
内科学   704篇
皮肤病学   35篇
神经病学   98篇
特种医学   114篇
外科学   400篇
综合类   351篇
预防医学   207篇
眼科学   14篇
药学   237篇
  2篇
中国医学   94篇
肿瘤学   92篇
  2024年   8篇
  2023年   27篇
  2022年   60篇
  2021年   92篇
  2020年   63篇
  2019年   71篇
  2018年   64篇
  2017年   71篇
  2016年   65篇
  2015年   130篇
  2014年   115篇
  2013年   153篇
  2012年   220篇
  2011年   239篇
  2010年   161篇
  2009年   159篇
  2008年   172篇
  2007年   173篇
  2006年   141篇
  2005年   161篇
  2004年   126篇
  2003年   111篇
  2002年   80篇
  2001年   60篇
  2000年   56篇
  1999年   28篇
  1998年   29篇
  1997年   23篇
  1996年   17篇
  1995年   19篇
  1994年   10篇
  1993年   19篇
  1992年   11篇
  1991年   11篇
  1990年   9篇
  1989年   14篇
  1988年   13篇
  1987年   9篇
  1986年   14篇
  1985年   5篇
  1984年   10篇
  1983年   6篇
  1982年   8篇
  1980年   7篇
  1978年   8篇
  1977年   8篇
  1976年   7篇
  1975年   5篇
  1970年   6篇
  1968年   4篇
排序方式: 共有3100条查询结果,搜索用时 15 毫秒
61.
Renal impairment is an important predictor of mortality after percutaneous coronary intervention and may increase the restenosis rate. However, the relation between restenosis and the risk of death in patients who have renal impairment remains unclear. We evaluated the incidences of repeat revascularization and mortality in patients who had renal impairment and those who did not and who received sirolimus-eluting stents or bare stents. A total of 1,080 consecutive patients treated for 1 year had available data to calculate baseline creatinine clearance. Patients received bare stents (first 6 months, n = 543) or sirolimus-eluting stents (last 6 months, n = 537) and were grouped according to the presence or absence of renal impairment (creatinine clearance <60 ml/min). Patients who had renal impairment had a higher mortality rate at 1 year (7.6% vs 2.5%, hazard ratio 3.14, 95% confidence interval 1.68 to 5.88, p <0.01), with no differences in mortality between patients who received bare stents and those who received sirolimus-eluting stents (hazard ratio 0.91, 95% confidence interval 0.49 to 1.68, p = 0.8). The incidence of target vessel revascularization decreased significantly in patients who were treated with sirolimus-eluting stents and did not have renal impairment (hazard ratio 0.59, 95% confidence interval 0.39 to 0.90, p = 0.01) and in those who had decreased renal function (hazard ratio 0.37, 95% confidence interval 0.15 to 0.90, p = 0.03). Thus, sirolimus-eluting stents compared with conventional stents decreased clinical restenosis in patients who had renal impairment. However, this benefit was not paralleled by a decrease in the risk of death in this population. It seems unlikely that restenosis could be a contributing factor that influenced the increased mortality of patients who had impaired renal function.  相似文献   
62.
Elevated plasma levels of B-type natriuretic peptide (BNP) and N-terminal pro-BNP (NT-pro-BNP) are seen in the setting of cardiac ischemia and are associated with adverse outcomes in patients with coronary artery disease. The mechanisms leading to natriuretic peptide elevation in patients with coronary artery disease, including the contribution of coronary atherosclerosis itself, have not been fully elucidated. Measurement of NT-pro-BNP, electron beam computed tomography, and cardiac magnetic resonance imaging were performed in 2,445 subjects from the Dallas Heart Study who were free of heart failure and renal insufficiency. Electron beam computed tomography-determined coronary artery calcium scores were categorized as none (<10), mild (> or =10 to <100), moderate (> or =100 to <400), and severe (> or =400). NT-pro-BNP levels increased significantly across increasing coronary artery calcium score categories (p <0.0001 for trend). In multivariate models adjusted for age, gender, race, body mass index, hypertension, history of myocardial infarction, angina, angiotensin-converting enzyme inhibitor use, beta-blocker use, left ventricular (LV) ejection fraction, and LV mass, higher coronary artery calcium scores remained independently associated with higher log NT-pro-BNP levels (p = 0.03). This association persisted in similar models excluding patients with low LV ejection fractions, LV hypertrophy, angina pectoris, and a history of myocardial infarction. In conclusion, these findings support the hypothesis that coronary atherosclerosis may directly influence the activation of the cardiac neurohormonal system.  相似文献   
63.
64.
65.
Bartonella henselae is associated with a wide spectrum of clinical manifestations, including cat scratch disease, endocarditis and meningoencephalitis, in immunocompetent and immunocompromised patients. We report the first molecularly confirmed case of B. henselae infection in an AIDS patient in state of Rio de Janeiro, Brazil. Although DNA sequence of B. henselae has been detected by polymerase chain reaction in a lymph node biopsy, acute and convalescent sera were nonreactive.  相似文献   
66.
67.
68.
69.
70.
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