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   1073篇
  免费   47篇
  国内免费   5篇
耳鼻咽喉   16篇
儿科学   7篇
妇产科学   3篇
基础医学   111篇
口腔科学   33篇
临床医学   59篇
内科学   271篇
皮肤病学   11篇
神经病学   56篇
特种医学   50篇
外科学   184篇
综合类   2篇
预防医学   64篇
眼科学   23篇
药学   55篇
中国医学   6篇
肿瘤学   174篇
  2023年   13篇
  2022年   15篇
  2021年   51篇
  2020年   22篇
  2019年   18篇
  2018年   38篇
  2017年   29篇
  2016年   40篇
  2015年   31篇
  2014年   46篇
  2013年   50篇
  2012年   64篇
  2011年   66篇
  2010年   20篇
  2009年   36篇
  2008年   41篇
  2007年   45篇
  2006年   50篇
  2005年   53篇
  2004年   51篇
  2003年   50篇
  2002年   56篇
  2001年   22篇
  2000年   18篇
  1999年   25篇
  1998年   15篇
  1997年   12篇
  1996年   13篇
  1995年   6篇
  1994年   7篇
  1993年   3篇
  1992年   18篇
  1991年   10篇
  1990年   9篇
  1989年   10篇
  1988年   6篇
  1987年   3篇
  1986年   8篇
  1985年   3篇
  1984年   5篇
  1983年   7篇
  1980年   2篇
  1979年   13篇
  1978年   4篇
  1977年   4篇
  1976年   2篇
  1971年   3篇
  1970年   2篇
  1968年   3篇
  1966年   2篇
排序方式: 共有1125条查询结果,搜索用时 587 毫秒
61.
(Received for publication on Oct. 26, 1998; accepted on Nov. 11, 1999)  相似文献   
62.
Absolute configurations of the gastric antisecretory compound P371A1 (1) and its congener P371A2 (2) from Streptomyces sp. P371 were determined on the basis of identification of the methyl glycosides 9, 10, and 11 obtained by the acid degradation of 1 and 2, as well as application of the modified Mosher method to the P371A2 C-glycoside MTPA esters 7 and 8 and observation of the excitation chiralities in the P371A2 C-glycoside benzoate derivatives 5 and 6.  相似文献   
63.
An adult left adrenal neuroblastoma that extended into the left renal vein and inferior vena cava is reported. To the best of our knowledge, venous involvement of adrenal tumors has been reported in adrenal cortical carcinomas, but not in neuroblastomas. Differentiation of renal and adrenal tumors is also discussed.  相似文献   
64.
65.
66.
67.
We examined mechanoradical formation in the grinding process of commercial tablets using electron spin resonance (ESR). Mechanoradicals were detected in all tested samples (23 types of commercial tablets) when the ball-milling of tablets was conducted under anaerobic conditions and some were fairly stable even in air. Thus the grinding may cause changes in the physicochemical properties of ingredients included in commercial tablets. Because high quality is demanded in pharmaceuticals, these results suggest more caution should be taken in the grinding of commercial tablets in hospitals and pharmacies.  相似文献   
68.
Loss of function of p16 gene and prognosis of pulmonary adenocarcinoma   总被引:6,自引:0,他引:6  
BACKGROUND: Stepwise progression of peripheral-type lung adenocarcinoma was characterized morphologically and was related to prognosis. Expression of the tumor suppressor gene p16 in pulmonary adenocarcinoma decreased, mainly as a result of aberrant methylation of the CpG islands of the promoter region. METHODS: Aberrant methylation status of the p16 promoter region, the expression of its product, and loss of heterozygosity (LOH) on 9p21 were examined in surgically resected lung specimens from 57 patients (28 males and 29 females) with peripheral-type lung adenocarcinoma measuring 相似文献   
69.
From May 1990 to November 1997, 24 cases of severe slipped capital femoral epiphysis were treated by an osteotomy that is a modification of the Hungria-Kramer intertrochanteric osteotomy proposed by Sugioka (Hungria-Kramer-Sugioka osteotomy or HKS osteotomy). The degree of displacement as seen on the frog-leg lateral radiograph of the proximal femur was measured according to the deviation of the longitudinal axis of the epiphysis from the center line of the neck (Fish classification). All hips were considered as grade III and underwent HKS osteotomy. Sugioka's radiographic study (true AP view with the limb internally rotated until the patella is perpendicular to the x-ray beam, and lateral view with the hip in 90 degrees flexion and 45 degrees abduction) was performed before surgery to show that the real direction of the slip was posterior in relation to the neck. Clinical results were assessed according to Merle-D'Aubigné and Postel system modified by Charnley (hip score system that takes into consideration pain, gait, and joint motion). Roentgenographic results were considered good if none of the following was present: joint space decreased by more than 2 mm (chondrolysis), avascular necrosis of the femoral head, neck-shaft angle of less than 120 degrees, nonunion at the osteotomy site, and a epiphyseal plate still open. Follow-up varied from 31 to 120 months (average 65.1 months).  相似文献   
70.
We describe herein magnetic resonance (MR) features of ipsilateral mamillary body atrophy after infarction of the posterior cerebral artery (PCA) territory. During the period May 2000 through July 2004, 13 patients with infarction of the PCA territory underwent cranial MR imaging in the chronic stage. Two 1.5-T scanners were used to obtain axial T1- and T2-weighted images with conventional spin-echo and fast spin-echo pulse sequences, respectively. The slice thickness was 6 mm, with a 2-mm interslice gap. Five of the 13 patients with PCA territory infarction had ipsilateral mamillary body atrophy. However, this asymmetry of the mamillary bodies was unclear in two of the five patients because of the thickness of the axial image slices. All five patients had a temporo–parieto–occipital infarction. The remaining eight patients had a parieto–occipital or an occipital infarction. Unilateral transneuronal mamillary body degeneration after infarction of the ipsilateral PCA territory including the posteromedial temporal lobe can be detected on conventional thick axial MR images.  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