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   1368篇
  免费   198篇
  国内免费   18篇
耳鼻咽喉   37篇
儿科学   52篇
妇产科学   19篇
基础医学   124篇
口腔科学   38篇
临床医学   207篇
内科学   293篇
皮肤病学   102篇
神经病学   76篇
特种医学   133篇
外科学   189篇
综合类   94篇
现状与发展   30篇
预防医学   60篇
眼科学   15篇
药学   32篇
中国医学   3篇
肿瘤学   80篇
  2024年   14篇
  2023年   179篇
  2022年   13篇
  2021年   18篇
  2020年   57篇
  2019年   22篇
  2018年   51篇
  2017年   48篇
  2016年   39篇
  2015年   56篇
  2014年   82篇
  2013年   60篇
  2012年   25篇
  2011年   33篇
  2010年   77篇
  2009年   88篇
  2008年   35篇
  2007年   57篇
  2006年   21篇
  2005年   22篇
  2004年   15篇
  2003年   22篇
  2002年   24篇
  2001年   19篇
  2000年   20篇
  1999年   31篇
  1998年   39篇
  1997年   50篇
  1996年   41篇
  1995年   36篇
  1994年   29篇
  1993年   34篇
  1992年   14篇
  1991年   9篇
  1990年   12篇
  1989年   22篇
  1988年   24篇
  1987年   19篇
  1986年   7篇
  1985年   11篇
  1984年   7篇
  1983年   6篇
  1982年   9篇
  1981年   11篇
  1980年   17篇
  1978年   8篇
  1976年   14篇
  1975年   11篇
  1974年   6篇
  1973年   5篇
排序方式: 共有1584条查询结果,搜索用时 15 毫秒
1.
2.
Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence.  相似文献   
3.
4.
Defecography in multiple sclerosis patients with severe constipation   总被引:3,自引:0,他引:3  
Gill  KP; Chia  YW; Henry  MM; Shorvon  PJ 《Radiology》1994,191(2):553
  相似文献   
5.
6.
7.
Detailed microelectrode maps of the hand representation were derived in cortical areas 3b and 1 from a series of normal adult owl and squirrel monkeys. While overlap relationships were maintained, and all maps were internally topographic, many map features varied significantly when examined in detail. Variable features of the hand representations among different monkeys included a) the overall shapes and sizes of hand surface representations; b) the actual and proportional areas of representations of different skin surfaces and the cortical magnifications of representations of specific skin surfaces, which commonly varied severalfold in area 3b and manyfold in area 1; c) the topographic relationships among skin surface representations, with skin surfaces that were represented adjacently in some monkeys represented in locations many hundreds of microns apart in others; d) the internal orderliness of representations; e) the completeness of representations of the dorsal hand surfaces; and f) the skin surfaces represented along the borders of the hand representation. Owl monkey maps were, in general, internally more strictly topographic than squirrel monkey maps. In both species, area 3b was more strictly topographic and less variable than was area 1. The degree of individual variability revealed in these experiments is difficult to reconcile with the hypothesis that details of cortical maps are ontogenetically specified during a period in early life. Instead, we propose that differences in the details of cortical map structure are the consequence of individual differences in lifelong use of the hands. This conclusion is consistent with earlier studies of the consequences of peripheral nerve transection and digital amputation, which revealed that cortical maps are dynamically maintained and are alterable as a function of use or nerve injury in these monkeys (Merzenich et al., '83a,b, '84a; Merzenich, '86; Jenkins et al., '84; Jenkins and Merzenich, '87).  相似文献   
8.
Solitary bronchioloalveolar carcinoma: CT criteria   总被引:14,自引:0,他引:14  
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis.  相似文献   
9.
10.

Background  

We present the design of an open randomized multi-centre study on surgical versus conservative treatment of acute Achilles tendon ruptures. The study is designed to evaluate the effectiveness of conservative treatment in reducing complications when treating acute Achilles tendon rupture.  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