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   21486篇
  免费   1397篇
  国内免费   200篇
耳鼻咽喉   279篇
儿科学   707篇
妇产科学   551篇
基础医学   2901篇
口腔科学   309篇
临床医学   1751篇
内科学   4094篇
皮肤病学   391篇
神经病学   1535篇
特种医学   732篇
外国民族医学   1篇
外科学   2772篇
综合类   508篇
一般理论   24篇
预防医学   3136篇
眼科学   523篇
药学   1281篇
  2篇
中国医学   135篇
肿瘤学   1451篇
  2023年   182篇
  2022年   302篇
  2021年   649篇
  2020年   309篇
  2019年   548篇
  2018年   664篇
  2017年   479篇
  2016年   504篇
  2015年   582篇
  2014年   770篇
  2013年   1128篇
  2012年   1591篇
  2011年   1639篇
  2010年   972篇
  2009年   793篇
  2008年   1219篇
  2007年   1326篇
  2006年   1236篇
  2005年   1076篇
  2004年   1004篇
  2003年   930篇
  2002年   838篇
  2001年   460篇
  2000年   379篇
  1999年   343篇
  1998年   134篇
  1997年   116篇
  1996年   96篇
  1995年   89篇
  1994年   99篇
  1993年   72篇
  1992年   219篇
  1991年   204篇
  1990年   216篇
  1989年   236篇
  1988年   199篇
  1987年   198篇
  1986年   157篇
  1985年   148篇
  1984年   101篇
  1983年   80篇
  1981年   47篇
  1980年   37篇
  1979年   66篇
  1978年   37篇
  1977年   37篇
  1975年   46篇
  1974年   41篇
  1973年   43篇
  1972年   38篇
排序方式: 共有10000条查询结果,搜索用时 250 毫秒
1.
2.
3.
4.
5.
Facial motion is a primary source of social information about other humans. Prior fMRI studies have identified regions of the superior temporal sulcus (STS) that respond specifically to perceived face movements (termed fSTS), but little is known about the nature of motion representations in these regions. Here we use fMRI and multivoxel pattern analysis to characterize the representational content of the fSTS. Participants viewed a set of specific eye and mouth movements, as well as combined eye and mouth movements. Our results demonstrate that fSTS response patterns contain information about face movements, including subtle distinctions between types of eye and mouth movements. These representations generalize across the actor performing the movement, and across small differences in visual position. Critically, patterns of response to combined movements could be well predicted by linear combinations of responses to individual eye and mouth movements, pointing to a parts‐based representation of complex face movements. These results indicate that the fSTS plays an intermediate role in the process of inferring social content from visually perceived face movements, containing a representation that is sufficiently abstract to generalize across low‐level visual details, but still tied to the kinematics of face part movements.  相似文献   
6.
7.
This study deals with a series of operations to isolate the micro-cellulose from the palm tree spathe sheath by using a modified chemical method to take into account the low cost and the completion speed and its characterization using X-ray diffraction technique (XRD), infrared spectroscopy (FTIR) and scanning electron microscope coupled with element analyzer (SEM/EDX). The results showed that the extraction method succeeded in obtaining very pure microscopic fibers with a width of 2–10 μm with a crystallinity index equal to 79.21%, containing the two cellulose features Iβ and II, that, the conversion ratio of the first to the second was estimated at 32, 87%.  相似文献   
8.
9.

Objectives

The current study investigated the effects of two exercise interventions on cognitive function amongst breast cancer survivors.

Design

Pilot randomised-controlled trial.

Methods

Seventeen female cancer survivors (mean: 62.9 ± 7.8 years) were randomised into three groups: high-intensity interval training (HIIT, n = 6); moderate-intensity continuous training (MOD, n = 5); or wait-list control (CON, n = 6). The HIIT and MOD groups exercised on a cycle ergometer 3 days/week for 12-weeks. Primary outcomes were cognitive function assessments utilising CogState. Secondary outcomes were resting middle cerebral artery blood flow velocity, cerebrovascular reactivity and aerobic fitness (VO2peak). Data were analysed with General Linear Mixed Models and Cohen’s d effect sizes were calculated.

Results

All 17 participants who were randomised were available for follow-up analysis and adherence was similar for HIIT and MOD (78.7 ± 13.2% vs 79.4 ± 12.0%; p = 0.93). Although there were no significant differences in the cognitive and cerebrovascular outcomes, HIIT produced moderate to large positive effects in comparison to MOD and CON for outcomes including episodic memory, working memory, executive function, cerebral blood flow and cerebrovascular reactivity. HIIT significantly increased VO2peak by 19.3% (d = 1.28) and MOD had a non-significant 5.6% (d = 0.72) increase, compared to CON which had a 2.6% decrease.

Conclusions

This study provides preliminary evidence that HIIT may be an effective exercise intervention to improve cognitive performance, cerebrovascular function and aerobic fitness in breast cancer survivors. Considering the sample size is small, these results should be confirmed through larger clinical trials.  相似文献   
10.
While once considered as incurable systemic disease, treatment options for liver metastases have increased over the last 30 years and safety has improved dramatically, such that for a selected group of patients the hope of cure can now be offered with radical treatment, and low morbidity interventions can be offered which prolong survival, even in patients with more widely disseminated disease. Advances have been made in selection and surgical technique for liver resection and several adjuncts to resection now exist in the form of portal vein embolization, thermal ablation and targeted drug or radiotherapy delivery options. A natural consequence of these developments has been the delivery of services within fewer specialist units, with the result that later complications of therapy may present to local hospitals, rather than directly to the specialist centres. This article will describe the current common liver-directed therapies and outline the presentation and management of their complications.  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