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   930886篇
  免费   67592篇
  国内免费   1344篇
耳鼻咽喉   12957篇
儿科学   24357篇
妇产科学   23238篇
基础医学   132887篇
口腔科学   28242篇
临床医学   80536篇
内科学   183302篇
皮肤病学   19245篇
神经病学   72223篇
特种医学   36863篇
外国民族医学   79篇
外科学   152100篇
综合类   18040篇
现状与发展   1篇
一般理论   234篇
预防医学   61744篇
眼科学   21407篇
药学   72542篇
  3篇
中国医学   2163篇
肿瘤学   57659篇
  2018年   8979篇
  2017年   7036篇
  2016年   7773篇
  2015年   8873篇
  2014年   11989篇
  2013年   17515篇
  2012年   24111篇
  2011年   25062篇
  2010年   14814篇
  2009年   14281篇
  2008年   24632篇
  2007年   25716篇
  2006年   26505篇
  2005年   25464篇
  2004年   24569篇
  2003年   23625篇
  2002年   23182篇
  2001年   54731篇
  2000年   56557篇
  1999年   46960篇
  1998年   10740篇
  1997年   9468篇
  1996年   9600篇
  1995年   8927篇
  1994年   8285篇
  1993年   7597篇
  1992年   35495篇
  1991年   33916篇
  1990年   32738篇
  1989年   31877篇
  1988年   28992篇
  1987年   28255篇
  1986年   26291篇
  1985年   25146篇
  1984年   17837篇
  1983年   15146篇
  1982年   7801篇
  1981年   6777篇
  1979年   15781篇
  1978年   10606篇
  1977年   9054篇
  1976年   7872篇
  1975年   8628篇
  1974年   10467篇
  1973年   9862篇
  1972年   9361篇
  1971年   8854篇
  1970年   8427篇
  1969年   7927篇
  1968年   7205篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
141.
Schizophrenia is a chronic and severe psychiatric disorder that has profound impact on an individual’s life and on society. Thus, developing more effective therapeutic interventions is essential. Over the past quarter‐century, an abundance of evidence from pharmacologic challenges, post‐mortem studies, brain imaging, and genetic studies supports the role of glutamatergic dysregulation in the pathophysiology of schizophrenia, and the results of recent randomized clinical trials based on this evidence have yielded promising results. In this article, we review the evidence that alterations in glutamatergic neurotransmission, especially focusing on the N‐methyl‐d ‐aspartate receptor (NMDAR) function, may be a critical causative feature of schizophrenia, how this contributes to pathologic circuit function in the brain, and how these insights are revealing whole new avenues for treatment development that could reduce treatment‐resistant symptoms, which account for persistent disability.  相似文献   
142.
This paper reviews the published literature on a group of developmental disorders of the retina and retinal pigment epithelium which result in focal abnormalities in one or both eyes. They are often asymptomatic, found on routine examination and are generally non-progressive. Some are associated with other systemic abnormalities.Subject terms: Retinal diseases, Eye abnormalities  相似文献   
143.
BackgroundTIAregistry.org is an international cohort of patients with transient ischemic attack (TIA) or minor stroke within 7 days before enrollment in the registry. Main analyses of 1-year follow-up data have been reported.5 We conducted subanalysis on the baseline and 1-year follow-up data of Japanese patients.MethodsThe patients were classified into 2 groups based on Japanese ethnicity, Japanese (345) and non-Japanese (3238), and their baseline data and 1-year event rates were compared. We also determined risk factors and predictors of 1-year stroke.ResultsCurrent smoking, regular alcohol drinking, intracranial arterial stenosis, and small vessel occlusion; and hypertension, dyslipidemia, coronary artery disease, and extracranial arterial stenosis were more and less common among Japanese patients, respectively. Stroke risk was higher and TIA risk was lower at 1-year follow-up among Japanese patients. The baseline risk factors for recurrent stroke were diabetes, alcohol drinking, and large artery atherosclerosis. Independent predictors of 1-year stroke risk were prior congestive heart failure and alcohol consumption.ConclusionsThe two populations of patients featured differences in risk factors, stroke subtypes, and outcome events. Predictors of recurrent stroke among Japanese patients included congestive heart failure and regular alcohol drinking. Strategies to attenuate residual risk of stroke aside from adherence to current guidelines should take our Japanese-patient specific findings into account.  相似文献   
144.
Congenital heart disease is a rare but important finding in adults who experience sudden death. Examination of the congenitally malformed heart has historically been considered esoteric and best left to those with expertise. The Cardiac Risk in the Young cardiovascular pathology laboratory based at St George's University of London has now received over 6,000 cases. Of these, 21 congenitally malformed hearts were retained for research and educational purposes. Hearts were assessed using sequential segmental analysis, and causes of death were adjudicated based on thorough macroscopic examination and histology. Congenital malformations that were encountered included atrial septal defects, ventricular septal defects, tetralogy of Fallot, and transposition of the great arteries in both its regular and congenitally corrected variants. Findings also included hearts with mirror-imaged and isomeric atrial appendages. Direct causes of death included myocardial fibrosis, pulmonary hypertension, and hemorrhage. A small but notable proportion did not reveal a substrate for arrhythmia, raising the question of whether the terminal event was due to the congenital heart disease itself, or an underlying channelopathy. Here, we demonstrate the value of simple sequential segmental analysis in describing and categorizing the cases, with the concept of the “morphological method” serving to identify the distinguishing features of the cardiac components. Clin. Anat. 33:394–404, 2020. © 2019 Wiley Periodicals, Inc.  相似文献   
145.
146.
147.
We present the case of a 54‐year‐old patient with renal transplant who developed unusual vascular changes on the forearm distal to a functioning arteriovenous fistula, as well as a painful ulcerated lesion on her anterior abdominal wall. We believe that the diffuse dermal angioendotheliomatosis variant of reactive angioendotheliomatosis had a role in the pathogenesis of this patient's lesions.  相似文献   
148.
149.
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