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   1694350篇
  免费   133514篇
  国内免费   29693篇
耳鼻咽喉   19539篇
儿科学   48276篇
妇产科学   40356篇
基础医学   236289篇
口腔科学   41714篇
临床医学   180831篇
内科学   305644篇
皮肤病学   30233篇
神经病学   128965篇
特种医学   61523篇
外国民族医学   590篇
外科学   215346篇
综合类   97630篇
现状与发展   86篇
一般理论   488篇
预防医学   141047篇
眼科学   39249篇
药学   138090篇
  439篇
中国医学   27330篇
肿瘤学   103892篇
  2022年   18737篇
  2021年   28870篇
  2020年   21090篇
  2019年   23069篇
  2018年   28067篇
  2017年   23646篇
  2016年   23645篇
  2015年   31563篇
  2014年   41188篇
  2013年   50488篇
  2012年   71506篇
  2011年   77579篇
  2010年   47944篇
  2009年   41885篇
  2008年   63229篇
  2007年   65214篇
  2006年   64454篇
  2005年   62124篇
  2004年   53687篇
  2003年   51230篇
  2002年   47875篇
  2001年   68505篇
  2000年   70000篇
  1999年   59965篇
  1998年   19634篇
  1997年   18170篇
  1996年   16967篇
  1995年   16070篇
  1994年   14687篇
  1993年   12873篇
  1992年   43704篇
  1991年   42627篇
  1990年   41005篇
  1989年   38677篇
  1988年   35677篇
  1987年   34675篇
  1986年   32939篇
  1985年   31191篇
  1984年   23325篇
  1983年   19812篇
  1982年   11855篇
  1979年   20920篇
  1978年   14873篇
  1977年   12103篇
  1976年   11901篇
  1975年   12130篇
  1974年   14828篇
  1973年   14496篇
  1972年   13381篇
  1971年   12433篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
141.
142.
143.
144.
The relationship between stroke and physical disability was examined in a cohort of adult, Framingham, Massachusetts, residents who, between 1948 and 1951, were assembled for a longitudinal examination of cardiovascular disease. Multivariate analyses examined the amount of residual disability attributable to stroke among 2540 community-dwelling survivors, 27 years after their initial examination, after controlling for age, cardiovascular risk factors, other cardiovascular diseases, and eight general health conditions related to physical disability. Among men living in the community, a history of stroke explained 12% of the variance in physical disability. Suffering a stroke, however, was not as strongly related to physical disability among women living in the community, accounting for only 3% of the variance. Results suggest that although older men and women die from the same major causes, they may not be disabled by the same conditions.  相似文献   
145.
146.
Spinal epidural hematoma. Report of a case and review of the literature   总被引:3,自引:0,他引:3  
We report the case of a thoracic epidural hematoma at the T7-T9 level which occurred after placement of spinal epidural catheter for continuous anaesthesia in acute pancreatitis. The male patient felt a sudden back pain after six days of successful analgesia and became paraplegic 24 hours afterwards. An emergency laminectomy and removal of the hematoma were performed; however, the patient recovered only incompletely.We discuss the clinical signs and symptoms of spinal epidural hematoma as well as its diagnostics and therapy. The controversial views from the literature concernings its etiology are critically reviewed.  相似文献   
147.
Transcranial magnetic stimulation (TMS) and transcranial electrical stimulation (TES) of the human motor cortex produce a silent period (SP) following motor evoked potentials (MEPs). The early part of the SP can be explained by decreased alpha motor neuron excitability, whereas the late part is presumably due to suprasegmental mechanisms. In order to determine the level of the suprasegmental contribution to the generation of SPs, we recorded excitatory and inhibitory responses to TMS, TES, and percutaneous electrical brainstem stimulation (PBS) in the voluntarily activated first dorsal interosseous muscle of the hand. Stimulus intensities were set so that PBS and TES induced MEPs with areas equal to or larger than those of MEPs obtained with TMS. This procedure revealed that SPs were 49% and 83% shorter with TES and PBS, respectively, than with TMS. As TMS is more effective than TES or PBS in activating cortical interneurons, these findings support the idea that a significant component of the SP arises from intracortical mechanisms.  相似文献   
148.
A case is presented which demonstrates the potential utility of the extracranial-intracranial bypass procedure for the treatment of vasospasm after subarachnoid hemorrhage. Extracranial-intracranial bypass surgery offers another alternative to the treatment of patients with vasospasm who have failed aggressive medical management.  相似文献   
149.
N-3 fatty acid deficiency is described in a 7-year-old girl who had been fed solely by gastric tube from the age of 3 years. She had received the same nutrient during the last 22 months, supplying 16.2% of calories from linoleate and 0.07% from alpha-linolenate. She weighed 9.5 kg at the age of 3, and 10.3 kg at the start of the study, the weight being constant the last 15 months. She was now supplemented daily with 1.2 ml of a linseed- and cod liver-oil mixture (5:1, v/v), thereby increasing her alpha-linolenate intake to 0.71% and total N-3 fatty acids to 0.74% of total energy. Two months later, her rate of weight gain was 0.43 kg/month. After 5 months, the fatty acid supplement was changed to 7.5 ml of cod liver oil daily, thereby changing alpha-linolenate and total N-3 acid intake to 0.10% and 1.3% of total energy, respectively. Her rate of weight gain now increased to 0.64 kg/month, and her length increased from 117 to 122 cm in 5 months. The results indicate that the optimal dietary requirement for N-3 fatty acids in this child is higher than 0.74%, and extrapolation estimated the optimal requirement to be 1.1%-1.2% of total calories. The results suggest that N-3 fatty acids are required for normal growth in man.  相似文献   
150.
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