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   142513篇
  免费   6487篇
  国内免费   332篇
耳鼻咽喉   885篇
儿科学   3948篇
妇产科学   2862篇
基础医学   27796篇
口腔科学   787篇
临床医学   12632篇
内科学   11137篇
皮肤病学   490篇
神经病学   47717篇
特种医学   1803篇
外科学   5463篇
综合类   1286篇
现状与发展   1篇
一般理论   30篇
预防医学   14328篇
眼科学   3389篇
药学   12290篇
  7篇
中国医学   104篇
肿瘤学   2377篇
  2023年   2452篇
  2022年   3632篇
  2021年   4371篇
  2020年   4495篇
  2019年   3835篇
  2018年   4929篇
  2017年   5420篇
  2016年   5551篇
  2015年   5275篇
  2014年   8293篇
  2013年   9927篇
  2012年   7119篇
  2011年   6907篇
  2010年   6458篇
  2009年   6271篇
  2008年   5282篇
  2007年   5213篇
  2006年   4828篇
  2005年   4252篇
  2004年   3691篇
  2003年   3433篇
  2002年   3354篇
  2001年   3091篇
  2000年   3019篇
  1999年   2897篇
  1998年   1226篇
  1997年   1087篇
  1996年   1141篇
  1995年   1019篇
  1994年   829篇
  1993年   730篇
  1992年   1918篇
  1991年   1719篇
  1990年   1764篇
  1989年   1614篇
  1988年   1538篇
  1987年   1002篇
  1986年   570篇
  1985年   862篇
  1984年   945篇
  1983年   691篇
  1982年   811篇
  1981年   746篇
  1980年   656篇
  1979年   728篇
  1978年   619篇
  1977年   501篇
  1976年   548篇
  1975年   450篇
  1974年   452篇
排序方式: 共有10000条查询结果,搜索用时 25 毫秒
21.
Event-related potentials are a valuable tool for the study of human memory function. This selective review provides a brief introduction in models of recognition memory and then describes how ERPs can be used to investigate familiarity memory, an acontextual form of remembering that can be distinguished from the recollection of detailed information of prior events. ERP studies on the mid-frontal old/new effect, the putative electrophysiological correlate of familiarity memory are reviewed. It will be illustrated how familiarity memory is reflected in this effect, how it can electrophysiologically be dissociated from other forms of memory and which brain systems mediate this form of remembering. Recent studies will be reviewed that illustrate that familiarity is not only restricted to single items but can also support the retrieval of associative information.  相似文献   
22.
Despite numerous studies of approach- and avoidant mindsets, relatively little research has addressed the impact of such motivational orientations on performance and emotion in a real-time, multi-task setting. A laboratory simulation is reported that examines the influence of an induced approach-centered, an avoidance-centered, and a “neutral” motivational mindset upon multiple aspects of task performance, self-regulatory cognition, and affect. Undergraduate females randomly assigned to one of three mindset conditions performed a simulated automobile drive across one practice and two experimental trials. Dependent measures included divided attention, behavioral indicators of driving “cautiousness” in relatively safe straight roadway sections as well as during more risk-filled driving, multiple aspects of self-regulatory thinking (including self-monitoring, intended effort, and self-administered consequences), and positive and negative affect. Results revealed that the avoidant mindset produced poorer executive attention (i.e., fewer correctly detected divided attention events), more “cautious” driving behavior and reduced performance variability (i.e., greater control) when driving on presumably safe, straight roadway sections, lower self-reports of intended effort, and greater negative affect relative to the approach mindset. Results are intepreted within a self-regulation-centered motivational framework. Implications of the multi-task simulation for the study of normal and disordered adjustment are considered.  相似文献   
23.
24.
We assessed midsagittal corpus callosum size in sickle cell disease (SCD) and its relationship to lesion volume, lesion location, and cognitive functioning. Twenty-eight children with SCD and 16 demographic controls completed magnetic resonance imaging (MRI) and neuropsychological testing. Corpus callosum (CC) size was smaller for children with silent infarcts (n = 8) or overt stroke (n = 8) than for those without visible infarcts (n = 12) or control participants. Lesion volume was a robust predictor of IQ and other cognitive scores; total CC size did not typically add explanatory power for these measures. The size of the rostral body of the CC, however, independently predicted measures of distractibility, speeded production, and working memory. Posterior CC size was also decreased among many of the children with SCD, even in the absence of visible infarcts in this region. Brain morphology appears to provide additional information about SCD-related effects on the brain above and beyond visible infarcts.  相似文献   
25.
26.
27.
28.
Gaucher's disease is a clinically heterogeneous disorder, including neuropathic and non-neuropathic variants. Among patients with non-neuropathic (type I disease), the wide variability in age of onset and the differential pattern and severity of disease expression complicate decision-making in relation to treatment. Optimal care may necessitate both palliative and adjunctive therapies. In the more mildly affected patient without clear signs of disease progression, the main issue is the appropriate time to intervene. In moderately to severely affected patients, the challenges include selection of an optimal treatment regimen and dealing with residual disease burden. Eventually, in well-controlled patients, guidance will be required on long-term maintenance regimens that will have to take the cost of care into consideration. Guidelines reached by consensus will hopefully reduce variation in clinical practice and promote integrated care pathways.  相似文献   
29.
30.
Social phobia, fear of negative evaluation and harm avoidance.   总被引:1,自引:0,他引:1  
This naturalistic, prospective investigation examined the role of fear of negative evaluation and the personality trait of harm avoidance in the anxiety levels of treated social phobia patients. One hundred and fifty-seven patients with DSM-IV social phobia were assessed before starting treatment and were then followed for up to two years. As expected, greater fear of negative evaluation and higher scores of harm avoidance were associated with greater anxiety at the 6 month follow-up, and harm avoidance remained a significant predictor at 24 months. However, no evidence was found for an interaction between the personality and cognitive variables examined. The findings are discussed in terms of the relative independence of these factors, as well as their potential implications for the treatment of this disorder.  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