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   240897篇
  免费   37880篇
  国内免费   2794篇
耳鼻咽喉   6133篇
儿科学   7533篇
妇产科学   3730篇
基础医学   15260篇
口腔科学   3730篇
临床医学   35433篇
内科学   66951篇
皮肤病学   8807篇
神经病学   23435篇
特种医学   10020篇
外国民族医学   1篇
外科学   55677篇
综合类   1025篇
现状与发展   72篇
一般理论   194篇
预防医学   13286篇
眼科学   5101篇
药学   6680篇
中国医学   145篇
肿瘤学   18358篇
  2024年   750篇
  2023年   5438篇
  2022年   2609篇
  2021年   6167篇
  2020年   7547篇
  2019年   4843篇
  2018年   10406篇
  2017年   9453篇
  2016年   10613篇
  2015年   10940篇
  2014年   18928篇
  2013年   20201篇
  2012年   12810篇
  2011年   12904篇
  2010年   14291篇
  2009年   17550篇
  2008年   11903篇
  2007年   9946篇
  2006年   12183篇
  2005年   9429篇
  2004年   8129篇
  2003年   6707篇
  2002年   6294篇
  2001年   4302篇
  2000年   3422篇
  1999年   3802篇
  1998年   4422篇
  1997年   4084篇
  1996年   3842篇
  1995年   3688篇
  1994年   2341篇
  1993年   1974篇
  1992年   1703篇
  1991年   1705篇
  1990年   1327篇
  1989年   1441篇
  1988年   1287篇
  1987年   1101篇
  1986年   1151篇
  1985年   986篇
  1984年   892篇
  1983年   821篇
  1982年   846篇
  1981年   727篇
  1980年   614篇
  1979年   454篇
  1978年   514篇
  1977年   568篇
  1975年   409篇
  1972年   399篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
42.
43.
44.
45.
Bowel diseases of prematurity, including necrotizing enterocolitis, are dreaded ailments of neonates. Early diagnosis is difficult, with clinical and radiographic findings often inconclusive. We present a novel use of contrast-enhanced ultrasound in detection of pediatric bowel disease. Early identification of compromised blood flow or an at-risk bowel can be quantitatively detected and monitored. This ability has implications for guidance of emerging therapies, allowing targeting of inflammation. These findings represent an advancement in detection of bowel disease in neonates.  相似文献   
46.
The association between asbestos exposure, mainly in occupational settings, and malignant mesothelioma has been well established; this has prompted several countries to establish mesothelioma epidemiologic surveillance programs often at the request of national agencies. This review compares currently existing mesothelioma registries worldwide to develop a concept model for a US real-time case capture mesothelioma registry. Five countries were identified with a mesothelioma specific registry, including Italy, France, UK, Australia, and South Korea. All, except the UK, used interviews to collect exposure data. Linkage with the national death index was available or was in future plans for all registries. The registries have limited information on treatment, quality of life, and other patient-centered outcomes such as symptoms and pain management. To thoroughly collect exposure data, “real-time” enrollment is preferable; to maximize the capture of mesothelioma cases, optimal coverage, and a simplified consent process are needed.  相似文献   
47.
48.
Polyethylene (PE) has been used extensively in knee arthroplasty since the mid 20th century. Progress in material manufacturing and processing has led to newer polyethylenes over last few decades with different material properties. It has been established that PE wear in knee arthroplasty causes particle induced osteolysis which is the main reason for late failure and requires revision surgery. Although there are various causes of wear, the properties of PE have long been a matter of investigation as a contributory factor. The advent of newer highly cross linked PE has been shown to improve wear rates in hip arthroplasty but the benefits have not been shown to be of the same degree in knee arthroplasty. The laboratory and clinical studies so far are limited and slightly conflicting in their conclusions. The risks of using highly cross linked PE in knee arthroplasty include tibial post fracture, disruption of locking mechanism, liner fracture which can lead to increased wear and osteolysis. The current evidence suggests that highly cross linked polyethylenes should be used with caution and only considered in younger active patients. The results of a recently completed randomized trial to compare the conventional with high molecular weight PE in knee arthroplasty are awaited.  相似文献   
49.
50.
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