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   2380520篇
  免费   199387篇
  国内免费   5070篇
耳鼻咽喉   34395篇
儿科学   72900篇
妇产科学   63218篇
基础医学   335977篇
口腔科学   67801篇
临床医学   216795篇
内科学   468521篇
皮肤病学   48106篇
神经病学   201296篇
特种医学   96320篇
外国民族医学   893篇
外科学   361529篇
综合类   58488篇
现状与发展   2篇
一般理论   988篇
预防医学   190566篇
眼科学   55765篇
药学   178996篇
  12篇
中国医学   5042篇
肿瘤学   127367篇
  2018年   24747篇
  2017年   19232篇
  2016年   20984篇
  2015年   23968篇
  2014年   34371篇
  2013年   51685篇
  2012年   69950篇
  2011年   73582篇
  2010年   43305篇
  2009年   41525篇
  2008年   69579篇
  2007年   73929篇
  2006年   74781篇
  2005年   72805篇
  2004年   69865篇
  2003年   67517篇
  2002年   66623篇
  2001年   112713篇
  2000年   116792篇
  1999年   98686篇
  1998年   28089篇
  1997年   25755篇
  1996年   25614篇
  1995年   24763篇
  1994年   23280篇
  1993年   21517篇
  1992年   79336篇
  1991年   76432篇
  1990年   73591篇
  1989年   70828篇
  1988年   65836篇
  1987年   64799篇
  1986年   61318篇
  1985年   58394篇
  1984年   44157篇
  1983年   37551篇
  1982年   22804篇
  1981年   20235篇
  1979年   41229篇
  1978年   28918篇
  1977年   24249篇
  1976年   22755篇
  1975年   23907篇
  1974年   29592篇
  1973年   28010篇
  1972年   26210篇
  1971年   24143篇
  1970年   22725篇
  1969年   21064篇
  1968年   19115篇
排序方式: 共有10000条查询结果,搜索用时 20 毫秒
21.
22.
Adjuvant irradiation is the standard treatment after breast conservative surgery. Normofractionated regimen with an overall treatment time of 5 to 6 weeks is often considered as a limiting factor for irradiation compliance. In order to answer this issue, moderate and more recently extreme hypofractionated protocols appeared. We report here oncological outcomes and toxicity of hypofractionated breast irradiation. After defining the frame of moderate and extreme hypofractionated breast irradiations based on overall treatment time, patient selection criteria were listed. According to their levels of proof, the results of moderate and extreme hypofractionated breast irradiation were analysed. Overall treatment time for moderate hypofractionated breast irradiation ranged from 3 to 4 weeks, while for extreme hypofractionated breast irradiation, it was less than 1 week. For moderate hypofractionated breast irradiation, whole breast irradiation was currently performed with or without lymph node irradiation. Moderate hypofractionated breast irradiation has proven to be as safe and as efficient as normofractionated breast irradiation with level IA evidence. For extreme hypofractionated breast irradiation, phase III randomized trials confirmed that accelerated partial breast irradiation was non-inferior in terms of local control compared to normofractionated whole breast irradiation (with external beam radiation therapy and multicatheter brachytherapy), with similar acute and late toxicity. While the use of intraoperative breast irradiation remains under debate, new very accelerated partial breast irradiation (overall treatment time not exceeding 2 days) protocols emerged with encouraging results. Accelerated partial breast irradiation is warranted for extreme hypofractionated breast irradiation and is indicated for low-risk breast cancers. Moderate and extreme hypofractionated breast irradiation regimens are validated and can be routinely proposed according to patient selection criteria.  相似文献   
23.
Aims. Functional connectivity is providing new insights into the network nature of epilepsy with growing clinical applications. Our objective was to validate a novel magnetoencephalography‐based method to non‐invasively measure the epileptic network. Methods. We retrospectively identified pediatric and adult patients with refractory focal epilepsy who underwent pre‐surgical magnetoencephalography with subsequent intracranial electrographic monitoring. Magnetoencephalography tracings were visually reviewed, and interictal epileptiform discharges (“spikes”) were individually marked. We then evaluated differences in whole‐brain connectivity during brief epochs preceding the spikes and during the spikes using the Network‐Based Statistic to test differences at the network level. Results. In six patients with statistically‐significant network differences, we observed substantial overlap between the spike‐associated networks and electrographically active areas identified during intracranial monitoring (the spike‐associated network was 78% and 83% sensitive for intracranial electroencephalography‐defined regions in the irritative and seizure onset zones, respectively). Conclusion. These findings support the neurobiological validity of the spike‐associated network method. Assessment of spike‐associated networks has the potential to improve surgical planning in epilepsy surgery patients by identifying components of the epileptic network prior to implantation.  相似文献   
24.
25.
26.
27.
Secondary tricuspid regurgitation (TR) caused by right ventricular enlargement in the setting of left heart disease/pulmonary hypertension has been well described. In contrast, that associated with right atrial enlargement—atrial functional TR (AF‐TR)—remains largely underappreciated. AF‐TR most often occurs in the setting of lone atrial fibrillation, although it is also seen in its absence (idiopathic AF‐TR). Several recent studies have found that the prevalence, hemodynamic significance, and prognosis of AF‐TR are not inconsequential, suggesting increased physician awareness of this novel clinical entity is warranted. This article discusses the pathogenesis, echocardiographic findings, and treatment of this underappreciated cause of secondary TR.  相似文献   
28.
29.
30.
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