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   2067816篇
  免费   143458篇
  国内免费   4779篇
耳鼻咽喉   29977篇
儿科学   64029篇
妇产科学   60312篇
基础医学   289831篇
口腔科学   60202篇
临床医学   174041篇
内科学   408318篇
皮肤病学   45821篇
神经病学   164834篇
特种医学   82653篇
外国民族医学   749篇
外科学   323350篇
综合类   46549篇
现状与发展   6篇
一般理论   662篇
预防医学   145870篇
眼科学   48456篇
药学   152392篇
  4篇
中国医学   4408篇
肿瘤学   113589篇
  2018年   19084篇
  2015年   18921篇
  2014年   26750篇
  2013年   41106篇
  2012年   54235篇
  2011年   57486篇
  2010年   34571篇
  2009年   33407篇
  2008年   55281篇
  2007年   59768篇
  2006年   60425篇
  2005年   58949篇
  2004年   56971篇
  2003年   55319篇
  2002年   54388篇
  2001年   95465篇
  2000年   98320篇
  1999年   83481篇
  1998年   22853篇
  1997年   20789篇
  1996年   20273篇
  1995年   19017篇
  1994年   18001篇
  1993年   16760篇
  1992年   65036篇
  1991年   62768篇
  1990年   61518篇
  1989年   59860篇
  1988年   55780篇
  1987年   54740篇
  1986年   52585篇
  1985年   50023篇
  1984年   37482篇
  1983年   31909篇
  1982年   19209篇
  1981年   17277篇
  1979年   35740篇
  1978年   25298篇
  1977年   21898篇
  1976年   20055篇
  1975年   22538篇
  1974年   26797篇
  1973年   25822篇
  1972年   24756篇
  1971年   23062篇
  1970年   21982篇
  1969年   20926篇
  1968年   19764篇
  1967年   17990篇
  1966年   16681篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Priori  A.  Cogiamanian  F.  Mrakic-Sposta  S. 《Neurological sciences》2006,27(4):s307-s309
Neurological Sciences - Spasticity arises from lesions involving the corticoreticulospinal system in the brain, brainstem or spinal cord. Abnormal suprasegmental influences lead to increased spinal...  相似文献   
92.
93.
A new semi-empirical formula for the evaluation of (n,(3)He) reaction cross-sections at the energy of 14.6 and 20 MeV is presented. Formula was derived using the analytical expression for the evaluation of the (3)He spectrum within the frame of pre-equilibrium exciton model. The systematics obtained is compared with the empirical formula for the (n,(3)He) reaction cross-section.  相似文献   
94.
95.
96.
This study was performed to evaluate the surgical strategy in patients with calvarial tumours, in order to design and modify a robot-assisted trepanation system. A total of 75 patients underwent craniectomy for the treatment of calvarial tumours during the 10-year period from 1993 to 2002. The patients' complaints, the size, location and histology of the tumour, and the various cranioplasty techniques used were analysed retrospectively. In a second procedure several craniectomies at typical locations according to the study's results were performed in a laboratory setting using a hexapod robotic tool, constructed at the Helmholtz-Institute, RWTH Aachen University, and plastic model heads. The workflow was documented and the reproducibility and the accuracy of the procedure were registered. A total of 83 surgical procedures were performed on 75 patients. The majority (87 %) of lesions treated surgically were located in the frontal, temporal and anterior parts of the parietal region. Histological examination revealed benign lesions in 66 % of the patients and dural involvement in 46 %. According to these results craniectomies were performed using the robotic system. Mean positioning accuracy of the robotic system while milling was 0.24 mm, with a standard deviation of 0.04 mm, and maximum error under 1 mm. Craniectomies leaving a 1-mm layer of the tabula interna intact to ensure a healthy dura were performed in several regions successfully. The majority of calvarial tumours, requiring surgical treatment in our patients, were located in cosmetically relevant areas in which drilling can be carried out with the robotic trepanation system. Consequently, the surgical approach had to be planned carefully in order to achieve a good cosmetic outcome.  相似文献   
97.
BG Aktuell     
This paper gives an overview of the changes in the sector of accident insurance companies over recent months and a prognosis for the changes that can still be expected, especially with reference to the election results.  相似文献   
98.
99.
Consecutive patients (n = 215) who were referred to optometric (55%) or multidisciplinary (45%) low-vision services and above 50 years of age were recruited from four hospitals in the Netherlands. They completed two vision-related quality of life questionnaires, the Vision Quality of Life Core Measure (VCM1) and the Low Vision Quality of Life Questionnaire (LVQOL), before their first visit with low-vision services and 1 year later. At follow-up, patients referred to multidisciplinary low-vision services had lower scores on the mobility subscale of the LVQOL than patients referred to optometric low-vision services [5.3 points; 95% confidence interval (CI): 0.2-10.5]. Paired sample t-tests for the two groups of patients taken together show improvement for the VCM1 (3.1 points; 95% CI: 0.6-5.6) and deterioration for the basic aspects of vision (3.5 points; 95% CI: 1.1-5.9) and the mobility (6.6 points; 95% CI: 3.7-9.5) subscales of the LVQOL. In conclusion, people referred to optometric services showed less deterioration in mobility than those referred to multidisciplinary services. No differences were observed for any of the other subscales of the LVQOL and the VCM1. Future research in this field should include randomized controlled designs comparing low-vision services with no treatment or placebo.  相似文献   
100.
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