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   3558篇
  免费   161篇
  国内免费   31篇
耳鼻咽喉   63篇
儿科学   56篇
妇产科学   26篇
基础医学   301篇
口腔科学   63篇
临床医学   197篇
内科学   811篇
皮肤病学   21篇
神经病学   288篇
特种医学   193篇
外科学   872篇
综合类   20篇
预防医学   127篇
眼科学   116篇
药学   123篇
中国医学   9篇
肿瘤学   464篇
  2023年   27篇
  2022年   46篇
  2021年   84篇
  2020年   54篇
  2019年   50篇
  2018年   82篇
  2017年   51篇
  2016年   81篇
  2015年   84篇
  2014年   106篇
  2013年   130篇
  2012年   173篇
  2011年   161篇
  2010年   89篇
  2009年   86篇
  2008年   151篇
  2007年   172篇
  2006年   163篇
  2005年   143篇
  2004年   134篇
  2003年   142篇
  2002年   137篇
  2001年   121篇
  2000年   104篇
  1999年   94篇
  1998年   40篇
  1997年   33篇
  1996年   40篇
  1995年   25篇
  1994年   46篇
  1993年   23篇
  1992年   85篇
  1991年   70篇
  1990年   86篇
  1989年   88篇
  1988年   72篇
  1987年   57篇
  1986年   66篇
  1985年   54篇
  1984年   28篇
  1983年   20篇
  1982年   15篇
  1979年   27篇
  1977年   19篇
  1974年   16篇
  1973年   14篇
  1971年   20篇
  1970年   12篇
  1969年   18篇
  1968年   15篇
排序方式: 共有3750条查询结果,搜索用时 15 毫秒
71.
We report an acute myocardial infarction in a patient with a single coronary artery. The right coronary artery arose from the middle portion in the left anterior descending artery through the transverse branch. This type of single coronary artery has not been previously reported. Moreover, this is the first report in which the culprit lesion in a patient with a single coronary artery was observed by intravascular ultrasound and coronary angioscopy. The patient underwent successful coronary stent deployment.  相似文献   
72.
BACKGROUND AND AIM OF THE STUDY: When replacing the regurgitant tricuspid valve in children, the decision to use either a bioprosthesis or a mechanical valve remains controversial. METHODS: The atrioventricular valve for the pulmonary circulation was replaced in 11 young patients aged between 8 months and 13 years. Complications of congenital cardiac malformation were present in seven patients, and Ebstein's anomaly in three; tricuspid valvular regurgitation was an isolated lesion in one patient. A bioprosthesis was implanted on seven occasions, and a bileaflet mechanical valve on eight, including re-replacement of the valve in four patients. RESULTS: One patient died two years after implantation due to respiratory problems. Tricuspid stenosis due to valve calcification occurred in four bioprostheses at between four and nine years after initial replacement (57%). In three of these cases the native valve leaflets had not been removed. Thrombosis occurred in one patient with a mechanical valve; rereplacement was successful. Anticoagulant-related hemorrhage occurred in another patient. Among patients receiving a mechanical valve, 83% of valves were dysfunction-free after five and ten years. CONCLUSION: When replacing an atrioventricular valve for the pulmonary circulation in children, we prefer to use a low-profile mechanical valve, especially when extensive repair of intracardiac malformation has been carried out, but ventricular function is good. In children with poor cardiac performance, a bioprosthesis is preferred, with total resection of the native valve leaflets.  相似文献   
73.
74.
Postpancreatectomy hemorrhage is a potentially life-threatening complication. We report herein our experience with a 65-year-old man with locally advanced pancreatic adenocarcinoma who underwent pancreatoduodenectomy with lymphadenectomy following neoadjuvant chemoradiotherapy. On postoperative day 45, he developed massive hematemesis. Angiography revealed active bleeding from the common hepatic artery, and transcatheter coil embolization of that vessel was successfully performed. On postoperative day 64, he again developed massive hematemesis. Angiography revealed active bleeding from the proximal superior mesenteric artery. Immediately after coil embolization of that vessel, bypass grafting between the superior mesenteric artery and the right common iliac artery was performed, using a greater saphenous vein graft. The combination of embolization and bypass grafting is an option for treatment of bleeding from the superior mesenteric artery in an emergent situation.Key words: Superior mesenteric artery, Bleeding, Bypass, Pancreatoduodenectomy, Postpancreatectomy hemorrhagePostpancreatectomy hemorrhage (PPH) is a rare but life-threatening complication, often associated with the presence of a pancreatic fistula or intraabdominal abscess.1 The mortality associated with arterial bleeding after pancreatoduodenectomy is reportedly between 14.3% and 30.7%.26 With recent advances in interventional radiology techniques, transcatheter arterial embolization (TAE) has become an alternative to surgical treatment.3,5,7,8 However, it may be difficult to treat these patients with interventional radiology techniques alone, given their often unstable condition. In addition, the inappropriate use of TAE for arterial bleeding, especially after pancreatoduodenectomy, can lead to end-organ infarction and subsequent infection. We report herein our experience with a patient who had bleeding from the superior mesenteric artery (SMA) after pancreatoduodenectomy. This patient was successfully treated using SMA coil embolization followed by creation of an SMA-iliac artery bypass using a greater saphenous vein graft.  相似文献   
75.
76.
77.
78.
79.
80.
We studied the mode of natural transmission of human T-cell leukemia virus type I (HTLV-I) in rabbits. Four virus-infected rabbits (2 males and 2 females) were individually mated with 4 noninfected rabbits. Two virus-infected females mated with noninfected males gave birth to 7 offspring, and 2 noninfected females mated with infected males delivered 5 offspring. Four of the seven offspring born to the virus- infected mothers seroconverted for HTLV-I when aged 6 to 13 weeks with antibody titers of 1:40 to 1:160. None of the five offspring born to the noninfected mothers became seropositive during the observation period of 6 months, however. Peripheral lymphocytes were cultured with T cell growth factor, and HTLV-I-carrying lymphoid cell lines were established from the four seroconverted rabbits. All four cell lines were of T cells positive for Ia antigens. In addition, none of five newborn rabbits killed immediately after birth to a virus-infected rabbit was infected with HTLV-I. These findings provide an experimental support for the milkborne transmission of HTLV-I from mother to child in humans and indicate that the virus is tropic for T cells in rabbits as well.  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