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   2656121篇
  免费   187778篇
  国内免费   3700篇
耳鼻咽喉   36189篇
儿科学   86198篇
妇产科学   71008篇
基础医学   397445篇
口腔科学   71492篇
临床医学   239115篇
内科学   511618篇
皮肤病学   58925篇
神经病学   206353篇
特种医学   99468篇
外国民族医学   532篇
外科学   398461篇
综合类   52906篇
现状与发展   12篇
一般理论   921篇
预防医学   206525篇
眼科学   62368篇
药学   198400篇
  11篇
中国医学   5265篇
肿瘤学   144387篇
  2019年   21634篇
  2018年   30148篇
  2017年   22562篇
  2016年   25359篇
  2015年   28536篇
  2014年   40102篇
  2013年   60240篇
  2012年   83747篇
  2011年   89342篇
  2010年   52852篇
  2009年   49723篇
  2008年   83610篇
  2007年   89375篇
  2006年   89943篇
  2005年   86960篇
  2004年   83382篇
  2003年   80462篇
  2002年   77771篇
  2001年   120278篇
  2000年   123223篇
  1999年   103441篇
  1998年   29941篇
  1997年   26193篇
  1996年   26536篇
  1995年   25036篇
  1994年   23020篇
  1993年   21734篇
  1992年   79667篇
  1991年   78433篇
  1990年   76735篇
  1989年   74000篇
  1988年   68006篇
  1987年   66952篇
  1986年   62525篇
  1985年   60191篇
  1984年   44742篇
  1983年   38039篇
  1982年   22338篇
  1979年   41336篇
  1978年   29619篇
  1977年   24423篇
  1976年   23697篇
  1975年   25948篇
  1974年   30742篇
  1973年   29323篇
  1972年   27475篇
  1971年   26085篇
  1970年   24020篇
  1969年   22960篇
  1968年   21211篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
62.
目的:探讨福赛类杆菌与人类唾液富脯蛋白相互作用的蛋白分子。方法:Western—blot方法。将人工合成唾液富脯蛋白用生物素标记,福赛类杆菌全菌蛋白凝胶电泳,半干转移至纤维膜上,观察二者的相互作用。结果:富脯蛋白能与分子量为85KD、65KD、60KD、以及49KD的福赛类杆菌蛋白发生结合。结论:福赛类杆菌存在与人类唾液富脯蛋白相互结合的粘附素。  相似文献   
63.
64.
65.
OBJECTIVES: To evaluate a novel method for localization of subdural electrodes in presurgical assessment of patients with drug-resistant focal epilepsy. METHODS: We studied eight consecutive patients with posterior epilepsy in whom subdural electrodes were implanted for presurgical evaluation. Electrodes were detected on post-implantation brain CT scans through a semiautomated procedure based on a MATLAB routine. Then, post-implantation CT scans were fused with pre-implantation MRI to localize the electrodes in relation to the underlying cortical structures. The reliability of this procedure was tested by comparing 3D-rendered MR images of the electrodes with electrode position as determined by intraoperative digital photography. RESULTS: In each patient, all electrodes could be correctly localized and visualized in a stereotactic space, thus allowing optimal surgery planning. The agreement between the procedure-generated images and the digital photographs was good according to two independent raters. The mean mismatch between the 3D images and the photographs was 2 mm. CONCLUSIONS: While our findings need confirmation on larger samples including patients with anterior epilepsy, this procedure allowed to localize subdural electrodes and to establish the spatial relationship of each electrode to the underlying brain structure, either normal or damaged, on brain convessity, basal and medial cortex. SIGNIFICANCE: Being simple, rapid, unexpensive, and reliable, this procedure holds promise to be useful to optimize epilepsy surgery planning.  相似文献   
66.
Neurons and related cell types often contain two major classes of neurosecretory vesicles, synaptic vesicles (SVs) and dense-core granules (DCGs), which store and release distinct cargo. SVs store and release classic neurotransmitters, which facilitate propagation of action potentials across the synaptic cleft, whereas DCGs transport, store, and release hormones, proteins, and neuropeptides, which facilitate neuronal survival, synaptic transmission, and learning. Over the past few years, there has been a major surge in our understanding of many of the key molecular mechanisms underlying cargo release from SVs and DCGs. This surge has been driven largely by the use of fluorescence microscopy (especially total internal reflection fluorescence microscopy) to visualize SVs or DCGs in living cells. This review highlights some of the recent insights into cargo release from neurosecretory vesicles provided by fluorescence microscopy, with emphasis on DCGs.  相似文献   
67.
Abstract Guillain-Barré syndrome (GBS) is a disease of the peripheral nervous system, which is caused by aberrant immune responses directed against some components of peripheral nerves. GBS is rarely accompanied by cardiovascular involvement. We describe a case of acute neuropathy complicated by sudden heart failure and left ventricular dysfunction which had a presumably neurogenic origin. Pathogenesis of acute heart failure is probably due to transitorial stunned myocardium and neurogenic cardiac injury. We show a rare case of transitorial and acute cardiac dysfunction by echocardiography and laboratory markers of heart failure.  相似文献   
68.
69.
A 27-year-old man was admitted with high fever and shivers eleven days after returning from vacation in Indonesia. Physical examination, laboratory values, abdominal ultrasound, and chest x-ray were not conclusive. All blood cultures yielded growth of Salmonella enterica serovar Typhi, and typhoid fever was diagnosed. Subsequently, the patient developed septic shock and pulmonary edema.In this case report epidemiological, clinical, and therapeutic aspects of typhoid fever are discussed with special emphasis on criteria for severe typhoid fever, which is treated with additional glucocorticoids.  相似文献   
70.
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