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   1121683篇
  免费   95147篇
  国内免费   16422篇
耳鼻咽喉   15409篇
儿科学   29149篇
妇产科学   26587篇
基础医学   138483篇
口腔科学   30208篇
临床医学   106972篇
内科学   186400篇
皮肤病学   20058篇
神经病学   74987篇
特种医学   44424篇
外国民族医学   171篇
外科学   159580篇
综合类   97730篇
现状与发展   72篇
一般理论   263篇
预防医学   98819篇
眼科学   23322篇
药学   97519篇
  369篇
中国医学   26894篇
肿瘤学   55836篇
  2022年   10002篇
  2021年   15030篇
  2020年   12331篇
  2019年   9945篇
  2018年   12269篇
  2017年   12857篇
  2016年   11883篇
  2015年   17339篇
  2014年   24103篇
  2013年   33352篇
  2012年   46467篇
  2011年   48919篇
  2010年   36788篇
  2009年   34059篇
  2008年   43858篇
  2007年   44926篇
  2006年   42692篇
  2005年   38834篇
  2004年   33853篇
  2003年   31034篇
  2002年   28172篇
  2001年   41615篇
  2000年   40944篇
  1999年   32446篇
  1998年   9560篇
  1997年   8823篇
  1996年   8764篇
  1992年   26785篇
  1991年   26178篇
  1990年   25709篇
  1989年   24733篇
  1988年   23270篇
  1987年   22947篇
  1986年   21800篇
  1985年   21150篇
  1984年   16422篇
  1983年   14027篇
  1982年   8892篇
  1979年   16739篇
  1978年   12115篇
  1977年   10185篇
  1976年   9331篇
  1975年   10148篇
  1974年   12641篇
  1973年   12136篇
  1972年   11541篇
  1971年   10685篇
  1970年   10218篇
  1969年   9909篇
  1968年   8900篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
53.
Bladder mucosa in urethral reconstructions   总被引:6,自引:0,他引:6  
  相似文献   
54.
Patient history and clinical examination are important for the diagnosis of degenerative joint disease. Here the typical statements of a patient suffering from early osteoarthritis are described and, as far as possible, explained. The joint in question must be systematically examined. Furthermore, the neighboring joints and soft-tissue structures, i.e., muscles, tendons etc., should be examined and evaluated with respect to their importance in hindering the functional chain. The neuroreflectory mechanisms involved herein are described.  相似文献   
55.
56.
Effects of the MAO-A-inhibitor brofaromine (BRO), 10 mg/kg po after repeated (twice daily for 14 days) administration on the spontaneous behavior (exploratory and basal locomotor activities) and the exploratory activity modified by methoxamine, clonidine and d-amphetamine in male Wistar rats were studied in both light and dark phases of a diurnal cycle (L: 0700-1900 h). After single administration BRO in the light phase had no effects. In the dark phase BRO decreased the exploration (62% of control, p less than 0.01), increased the clonidine-evoked hypoactivity and amphetamine-evoked hyperactivity. The L-D differences occurred also after repeated administration. BRO in the light phase did not influence the exploration, decreased basal locomotor activity, did not change methoxamine and clonidine action and potentiated the action of amphetamine. In the dark phase, however, it did not influence the exploration and basal locomotor activity, intensified the methoxamine effect, and did not change the clonidine and amphetamine actions. The results demonstrate that the effects of BRO on behavior in rats: 1) differ from the effects caused by other antidepressants which are not MAO inhibitors; 2) are phase-dependent after both single and repeated administration.  相似文献   
57.
A new range of stand magnifiers has been released by the COIL company in the United Kingdom. Examination of these magnifiers reveals that they fail to deliver the rated magnifications labelled prominently on the appliances, as a result of the manufacturer's conformance with the requirements of the German DIN standard and the use of back vertex power (F'v) rather than equivalent dioptric power (Fm) of the magnifier. In this study we provide information on the optometric parameters of these new stand magnifiers that will assist the more accurate specification of improvements in vision expected from their use.  相似文献   
58.
59.
An ultrasound contrast agent which survives transit through the pulmonary circulation after injection into a peripheral vein can also be used for the demonstration of flow characteristics in the peripheral organs. Such a substance (SH U 508 A, Schering AG, Berlin) was tested in the Gynecological Department of the University of Marburg for its suitability for enhancing color-coded Doppler signals in mammary diagnosis in a group of ten women with breast tumors. The observations made are compared with the histologically confirmed diagnoses. The very distinct enhancement of the color-coded Doppler signals allows reliable demonstration of the vascularization characteristics, not only of the malignant, but also of all benign solid tumors examined. Color signals were even recorded from normal mammary tissue, which means that the demonstration of perfusion can no longer be used on its own as a diagnostic criterion. Observation of the characteristics of the blood supply to a tumor might, on the other hand, be an advantage, not only in respect of tumor typing, but also as regards the prognosis of a tumor. In this connection, the registration of the arrival, retention and wash-out phases specific to a contrast agent appears to furnish particularly interesting information about the growth dynamics of a tumor.  相似文献   
60.
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