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   71599篇
  免费   9010篇
  国内免费   827篇
耳鼻咽喉   143篇
儿科学   2449篇
妇产科学   255篇
基础医学   3439篇
口腔科学   236篇
临床医学   13034篇
内科学   15146篇
皮肤病学   309篇
神经病学   8009篇
特种医学   1960篇
外国民族医学   5篇
外科学   5103篇
综合类   13603篇
一般理论   1篇
预防医学   3196篇
眼科学   869篇
药学   6501篇
  85篇
中国医学   4699篇
肿瘤学   2394篇
  2024年   36篇
  2023年   1503篇
  2022年   1866篇
  2021年   3643篇
  2020年   3678篇
  2019年   2814篇
  2018年   2686篇
  2017年   2901篇
  2016年   3095篇
  2015年   2844篇
  2014年   5115篇
  2013年   5830篇
  2012年   4381篇
  2011年   4604篇
  2010年   3650篇
  2009年   3378篇
  2008年   3362篇
  2007年   3527篇
  2006年   3197篇
  2005年   2857篇
  2004年   2563篇
  2003年   2418篇
  2002年   1665篇
  2001年   1416篇
  2000年   1241篇
  1999年   923篇
  1998年   790篇
  1997年   694篇
  1996年   597篇
  1995年   581篇
  1994年   484篇
  1993年   362篇
  1992年   342篇
  1991年   260篇
  1990年   212篇
  1989年   228篇
  1988年   218篇
  1987年   171篇
  1986年   171篇
  1985年   249篇
  1984年   172篇
  1983年   123篇
  1982年   152篇
  1981年   114篇
  1980年   78篇
  1979年   74篇
  1978年   56篇
  1977年   42篇
  1976年   30篇
  1975年   20篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Left ventricular (LV) pseudoaneurysm is a rare complication after myocardial infarction and cardiac surgery. Standard treatment remains surgical correction; however, percutaneous closure has been attempted in high risk surgical patients. We report a case of three dimensional echocardiography and cardiac CT defined LV pseudoaneurysm which was closed percutaneously using intracardiac echocardiography (ICE) and fluoroscopy guidance. Appropriate planning and guidance proved essential to the procedure with an excellent outcome. Percutaneous closure of LV pseudoaneurysms is safe and feasible in high risk surgical patients and with appropriate imaging modalities may be an alternative to surgical correction. © 2011 Wiley Periodicals, Inc.  相似文献   
2.
Background : Optical coherence tomography (OCT) and near‐infrared spectroscopy (NIRS) allow assessment of the anatomy (OCT) and composition (NIRS) of coronary lesions. We sought to examine the association between pre‐stenting lipid core plaque (LCP), as assessed by NIRS and post‐stenting thrombus formation, as assessed by OCT. Methods : We reviewed the angiograms of nine patients who underwent coronary stenting in association with NIRS and OCT imaging. A large LCP by NIRS was defined as at least three 2‐mm yellow blocks on the NIRS block chemogram with >200° angular extent. Intracoronary thrombus was defined as a mass of medium reflectivity protruding into the vessel lumen, discontinuous from the surface of the vessel wall. Results : Mean age was 67 ± 7 years, and all patients were men, presenting with stable angina (56%), unstable angina (11%), or acute myocardial infarction (33%). The mean vessel lipid core burden index (LCBI) was 120 ± 45, and the mean highest 6‐mm LCBI was 386 ± 190. Three patients had a large LCP and two of them (66%) developed intrastent thrombus after stent implantation compared to none of six patients without large LCPs (0%, P = 0.02). The thrombus resolved after intracoronary glycoprotein IIb/IIIa administration and balloon postdilation. Postprocedural myocardial infarction occurred in 33% versus 17% of patients with and without large LCP, respectively (P = 0.57). Conclusion : Stenting of large LCPs may be associated with intrastent thrombus formation, suggesting that more intensive anticoagulant and/or antiplatelet therapy may be beneficial in such lesions. © 2012 Wiley Periodicals, Inc.  相似文献   
3.
Despite drug eluting stents (DES), as compared to bare metal stents, have reduced in‐stent restenosis, complex and long lesions remains a challenge for interventional cardiologist. Their treatment is often associated with an unfavorable outcome, related to in‐stent restenosis, stent thrombosis, and target lesion revascularization. These complications may derive from the contact between metallic structures and coronary artery endothelium, and consequent overexpression of platelet activating factors, growth factors, and inflammatory cytokines. Recently, an additional mechanism has emerged as new cause of these complications: “stent fracture.” Several factors are involved in this phenomenon including material and stent platform, target vessel features, stent implantation technique, and implant duration. We reported a case of 69 years old man with rare early and complex DES fractures on right coronary that caused acute coronary syndrome 36 hr after a previous percutaneous coronary intervention.© 2012 Wiley Periodicals, Inc.  相似文献   
4.
5.
6.
7.
8.
9.
Thrombolysis is the most effective therapy for ischaemic stroke. The current guidelines and approvals have limited its use to patients available for treatment within 4.5 hours of onset and those aged 80 or less. There are also a number of other limitations derived from clinical trial protocols, i.e. minor and major strokes. The available evidence has indicated its possible efficacy in patients treated within 6 hours of onset and not fulfilling other limitations.Last year, the results of the IST-3 (Third International Stroke Trial: Thrombolysis) and a meta-analysis of all available trials including IST-3 were published. They point out the possible benefit of thrombolysis in patients not meeting the current criteria, which has been acknowledged in the Polish guidelines for management of stroke.  相似文献   
10.
Introduction: The dystrophic features in hindlimb skeletal muscles of female mdx mice are unclear. Methods: We analyzed force‐generating capacity and force decline after lengthening contraction‐induced damage (fragility). Results: Young (6‐month‐old) female mdx mice displayed reduced force‐generating capacity (?18%) and higher fragility (23% force decline) compared with female age‐matched wild‐type mice. These 2 dystrophic features were less accentuated in young female than in young male mdx mice (?32% and 42% force drop). With advancing age, force‐generating capacity decreased and fragility increased in old (20 month) female mdx mice (?21% and 57% force decline), but they were unchanged in old male mdx mice. Moreover, estradiol treatment had no effect in old female mdx mice. Conclusions: Female gender–related factors mitigate dystrophic features in young but not old mdx mice. Further studies are warranted to identify the beneficial gender‐related factor in dystrophic muscle. Muscle Nerve, 2013  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