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   496篇
  免费   23篇
  国内免费   3篇
耳鼻咽喉   10篇
儿科学   40篇
妇产科学   10篇
基础医学   38篇
口腔科学   3篇
临床医学   45篇
内科学   93篇
皮肤病学   5篇
神经病学   32篇
特种医学   19篇
外科学   71篇
综合类   7篇
一般理论   1篇
预防医学   28篇
眼科学   58篇
药学   23篇
中国医学   1篇
肿瘤学   38篇
  2024年   1篇
  2023年   5篇
  2022年   12篇
  2021年   24篇
  2020年   11篇
  2019年   23篇
  2018年   14篇
  2017年   14篇
  2016年   19篇
  2015年   10篇
  2014年   24篇
  2013年   27篇
  2012年   44篇
  2011年   38篇
  2010年   18篇
  2009年   16篇
  2008年   16篇
  2007年   28篇
  2006年   22篇
  2005年   20篇
  2004年   14篇
  2003年   18篇
  2002年   31篇
  2001年   11篇
  2000年   3篇
  1999年   11篇
  1998年   2篇
  1997年   2篇
  1995年   3篇
  1994年   2篇
  1993年   4篇
  1992年   3篇
  1991年   2篇
  1989年   2篇
  1988年   8篇
  1987年   4篇
  1985年   1篇
  1983年   2篇
  1982年   1篇
  1981年   2篇
  1980年   1篇
  1978年   2篇
  1975年   1篇
  1971年   4篇
  1970年   1篇
  1956年   1篇
排序方式: 共有522条查询结果,搜索用时 15 毫秒
1.
2.
3.
Purpose:COVID-19-associated mucormycosis (CAM) was a serious public health problem during the second wave of COVID-19 in India. We planned to analyze public perceptions by sentiment analysis of Twitter data regarding CAM.Methods:In this observational study, the application programming interface (API) provided by the Twitter platform was used for extracting real-time conversations by using keywords related to mucormycosis (colloquially known as “black fungus”), from May 3 to August 29, 2021. Lexicon-based sentiment analysis of the tweets was done using the Vader sentiment analysis tool. To identify the overall sentiment of a user on any given topic, an algorithm to label a user “k” based on their sentiments was used.Results:A total of 4,01,037 tweets were collected between May 3 and August 29, 2021, and the peak frequency of 1,60,000 tweets was observed from May 17 to May 23, 2021. Positive sentiment tweets constituted a larger share as compared to negative sentiment tweets, with weekly variations. A temporal analysis of the demand for utilities showed that the demand was high in the initial period but decreased with time, which was associated with the availability of resources.Conclusion:Sentiment analysis using Twitter data revealed that social media platforms are gaining popularity to express one’s emotions during the ongoing COVID-19 pandemic. In our study, time-based assessment of tweets showed a reduction over time in the frequency of negative sentiment tweets. The polarization in the retweet network of users, based on sentiment polarity, showed that the users were well connected, highlighting the fact that such issues bond our society rather than segregating it.  相似文献   
4.
5.
6.
The mitral valve aneurysm is a rare complication of infective endocarditis involving mitral or aortic valve. The perforation of the mitral valve aneurysm can lead to significant mitral regurgitation (MR) or thromboembolism, which can cause sudden hemodynamic deterioration. We describe here a case of healed infective endocarditis of the aortic valve with ruptured mitral valve aneurysm that led to severe MR. The aneurysm of the anterior mitral leaflet was diagnosed by two‐dimensional transthoracic echocardiography. In this case, three‐dimensional transthoracic echocardiography demonstrated the detailed morphology of mitral valve aneurysm which resulted in successful surgical repair of the aneurysm.  相似文献   
7.
8.

Background:

There is paucity of information on the relationship of quality of life (QOL) in obsessive compulsive disorder (OCD) and dysthymic disorder (DD) with disability grade in India.

Aim:

To assess the relation of QOL with disability level in OCD and DD.

Materials and Methods:

This hospital based study was conducted in a medical institution in Davanagere, Karnataka, India. Data was collected by using Diagnostic and Statistical Manual IV Text Revision (DSM IV TR) criteria, WHO QOL BREF and IDEAS. Relationship between disability grade and QOL was assessed by independent sample t test.

Results:

Mild disabled OCD patients had a significantly better QOL in the Q1 domain i.e. perception on quality of life as compared to moderately disabled patients (P < 0.05), while in other domains of QOL, there was no statistically significant difference (P > 0.05). But, QOL score in physical domain showed significant difference across disability grades (56.00, SD = 6.89; 48.50, SD = 12.28) in DD, but not in other domains.

Conclusion:

Perception of QOL is better in those with mild disability in OCD, but in DD, physical domain of QOL score is more in mild disability compared to moderate disability.  相似文献   
9.
10.
Protein phosphorylation and dephosphorylation events play a key role in memory formation and various protein kinases and phosphatases have been firmly associated with memory performance. Here, we determined expression changes of protein kinases and phosphatases following retrieval of spatial memory in CD1 mice in a Morris Water Maze task, using antibody microarrays and confirmatory Western blot. Comparing changes following single and consecutive retrieval, we identified stably and differentially expressed kinases, some of which have never been implicated before in memory functions. On the basis of these findings we define a small signaling network associated with spatial memory retrieval. Moreover, we describe differential regulation and correlation of expression levels with behavioral performance of polo‐like kinase 1. Together with its recently observed genetic association to autism‐spectrum disorders our data suggest a role of this kinase in balancing preservation and flexibility of learned behavior. © 2013 Wiley Periodicals, Inc.  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