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   118679篇
  免费   11292篇
  国内免费   9139篇
耳鼻咽喉   995篇
儿科学   1149篇
妇产科学   1179篇
基础医学   13970篇
口腔科学   2013篇
临床医学   16030篇
内科学   17904篇
皮肤病学   1247篇
神经病学   6292篇
特种医学   4573篇
外国民族医学   78篇
外科学   12073篇
综合类   20743篇
现状与发展   40篇
一般理论   6篇
预防医学   8209篇
眼科学   3355篇
药学   12231篇
  95篇
中国医学   7101篇
肿瘤学   9827篇
  2024年   431篇
  2023年   2029篇
  2022年   5013篇
  2021年   6391篇
  2020年   4798篇
  2019年   4055篇
  2018年   4220篇
  2017年   3742篇
  2016年   3600篇
  2015年   5488篇
  2014年   6746篇
  2013年   5963篇
  2012年   8549篇
  2011年   9451篇
  2010年   5988篇
  2009年   4753篇
  2008年   6089篇
  2007年   6050篇
  2006年   5841篇
  2005年   5897篇
  2004年   3846篇
  2003年   3507篇
  2002年   3014篇
  2001年   2686篇
  2000年   2829篇
  1999年   3025篇
  1998年   2060篇
  1997年   2103篇
  1996年   1625篇
  1995年   1528篇
  1994年   1330篇
  1993年   843篇
  1992年   1003篇
  1991年   805篇
  1990年   695篇
  1989年   667篇
  1988年   551篇
  1987年   492篇
  1986年   432篇
  1985年   330篇
  1984年   149篇
  1983年   129篇
  1982年   92篇
  1981年   102篇
  1980年   64篇
  1979年   61篇
  1978年   5篇
  1977年   14篇
  1976年   14篇
  1975年   10篇
排序方式: 共有10000条查询结果,搜索用时 6 毫秒
1.
European Archives of Oto-Rhino-Laryngology - Several polymorphisms in a disintegrin and metalloproteinase 33 (ADAM33) have been implicated in susceptibility to allergic rhinitis (AR), but the...  相似文献   
2.
3.
Patients with mechanic ankle instability experience increased tibiotalar and subtalar joint laxity. However, in vivo joint kinematics in functional ankle instability (FAI) patients and lateral ankle sprain (LAS) copers, especially during dynamic activities, are poorly understood. Ten FAI patients, 10 LAS copers, and 10 healthy controls were included in this study. A dual fluoroscopic imaging system was used to analyze the tibiotalar and subtalar joint kinematics during stair descent. Five key poses of stair descent were analyzed. Kinematic data from six degrees of freedom were calculated utilizing a solid modeling software. The range of motion and joint positions in each degree of freedom were compared among the three groups. The tibiotalar joints of FAI patients and LAS copers were significantly more inverted than those of healthy controls during the foot strike (p = 0.016, = 0.264). The subtalar joints of FAI patients were significantly more anteriorly translated (pose 2, p = 0.003, = 0.352; pose 3, p < 0.001, = 0.454; pose 4, p = 0.004, = 0.334), inverted (pose 4, p = 0.027, = 0.234; pose 5,p = 0.034, = 0.221), and externally rotated (pose 4, p = 0.037, = 0.217; pose 5; p = 0.004, = 0.331) than those of healthy controls during the mid‐stance and the heel off. The FAI patients showed excessive tibiotalar inversion and subtalar joint hypermobility during stair descent. Meanwhile, the LAS copers maintained subtalar joint stability, and only showed excessive tibiotalar inversion in foot strike. These data provide insight into the mechanisms behind the development of FAI after initial LAS. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1860–1867, 2019  相似文献   
4.
Abstract

Background

Comorbidities are commonly seen in patients with coronavirus disease 2019 (COVID-19), but the clinical implication is not yet well-delineated. We aim to characterize the prevalence and clinical implications of comorbidities in patients with COVID-19.  相似文献   
5.
6.
大脑后动脉交通前段及其内穿支研究   总被引:2,自引:0,他引:2  
本文介绍Willis动脉环后半环大脑后动脉及其内穿支的显微解剖,大脑后动脉交通前段内穿支是脑深部的重要供血血管之一,100%的病例双侧具有该血管。  相似文献   
7.
8.
Intravenous administration of human bone marrow stromal cells (hMSCs) after middle cerebral artery occlusion (MCAo) in rats provides functional benefit. We tested the hypothesis that these functional benefits are derived in part from hMSC production of growth and trophic factors. Quantitative sandwich enzyme‐linked immunosorbent assay (ELISA) of hMSCs cultured with normal and MCAo brain extracts were performed. hMSCs cultured in supernatant derived from ischemic brain extracts increased production of brain‐derived neurotrophic factor (BDNF), nerve growth factor (NGF), vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF). These neurotrophins and angiogenic growth factors increased in a post‐ischemia time‐dependent manner. The hMSC capacity to increase expression of growth and trophic factors may be the key to the benefit provided by transplanted hMSCs in the ischemic brain.  相似文献   
9.
This study evaluated the safety and efficacy of batroxobin in treating hyperfibrinogenemia for secondary stroke prevention. Patients with ischemic stroke or transient ischemic attack (TIA) were measured for plasma fibrinogen levels. Selected participants had concomitant hyperfibrinogenemia (plasma fibrinogen > or = 3.0 g/l). Patients enrolled between 1 July 2003 and 31 December 2004 were treated with batroxobin; patients enrolled between 1 January 2002 and 30 June 2003 were treated without batroxobin. Batroxobin was administered intermittently via intravenous injection at 3-monthly intervals. Patients in both groups were followed for 1 year. Any cerebrovascular events and suspected adverse events were recorded. In total, 112 ischemic stroke/TIA patients with concomitant hyperfibrinogenemia were enrolled, 52 being treated with batroxobin and 60 without batroxobin. Six patients (11.5%) with batroxobin and 16 patients (26.7%) without batroxobin had recurrent cerebral ischemic events during follow-up. Stroke/TIA recurrence in patients without batroxobin was higher than that in patients with batroxobin (P < 0.05). Two patients with batroxobin and two patients without batroxobin developed hemorrhagic stroke during follow-up. There were five deaths (9.6%) in the batroxobin group, and seven deaths (11.7%) in the nonbatroxobin group during follow-up (P > 0.05). Intermittent intravenous injection of batroxobin can efficiently reduce the risk for stroke/TIA recurrence in patients with concomitant hyperfibrinogenemia.  相似文献   
10.
近十年高血压病中医研究概况   总被引:1,自引:0,他引:1  
为了促进中医药治疗高血压病的进一步发展,深入进行高血压病中医的病因病机、治法方药、作用机制的相关研究,本文对近十年有代表性的文献进行归纳分析。  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