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   526330篇
  免费   29036篇
  国内免费   817篇
耳鼻咽喉   7209篇
儿科学   17389篇
妇产科学   14884篇
基础医学   78082篇
口腔科学   13084篇
临床医学   42517篇
内科学   106506篇
皮肤病学   12367篇
神经病学   41734篇
特种医学   18472篇
外国民族医学   142篇
外科学   75293篇
综合类   8729篇
现状与发展   1篇
一般理论   224篇
预防医学   41046篇
眼科学   11532篇
药学   37172篇
中国医学   1465篇
肿瘤学   28335篇
  2021年   5670篇
  2020年   3432篇
  2019年   6098篇
  2018年   11007篇
  2017年   7567篇
  2016年   7966篇
  2015年   9061篇
  2014年   10319篇
  2013年   16474篇
  2012年   25082篇
  2011年   25408篇
  2010年   14129篇
  2009年   11473篇
  2008年   22430篇
  2007年   24159篇
  2006年   22910篇
  2005年   22297篇
  2004年   21167篇
  2003年   19598篇
  2002年   18548篇
  2001年   18980篇
  2000年   19473篇
  1999年   16546篇
  1998年   3889篇
  1997年   3513篇
  1996年   3322篇
  1995年   3174篇
  1992年   11292篇
  1991年   11150篇
  1990年   10815篇
  1989年   10414篇
  1988年   9540篇
  1987年   9148篇
  1986年   8672篇
  1985年   8278篇
  1984年   6101篇
  1983年   5255篇
  1982年   3141篇
  1979年   5590篇
  1978年   4052篇
  1977年   3496篇
  1976年   3132篇
  1975年   3601篇
  1974年   4299篇
  1973年   4339篇
  1972年   4007篇
  1971年   3826篇
  1970年   3672篇
  1969年   3450篇
  1968年   3297篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
Enterococcus faecalis (E. faecalis) is a common cause of nosocomial infection in immunocompromised patients. The presence and dissemination of high‐risk clonal complexes, such as CC2, is an ongoing problem in hospitals. The aim of this work was to characterize 24 E. faecalis isolates from ICU patients undergoing selective decontamination of the digestive tract (SDD) by phenotypical (antimicrobial susceptibility) and genotypical (presence of virulence genes, RAPD‐PCR and MLST) methods. Our results showed high prevalence of the ST6 E. faecalis clone (91.6%), especially adapted to the hospital environment, with a multidrug resistance pattern and a multitude of putative virulence genes. In addition, ST179 (4.2%) and ST191 (4.2%) were detected. By RAPD–PCR analysis, the 22 isolates identified as ST6 showed six different DNA patterns, while the two remaining isolates, ST179 and ST191, showed two additional profiles. CC2 is a known clonal complex with high adaptability to hospital environment and worldwide distribution. The high prevalence of the ST6 clone in the studied population could be related to the presence of gentamicin in the SDD mixture since most strains were gentamicin resistant. Consequently, strict surveillance should be applied for rapid detection and control of this clone to prevent future spread outside the ICU.  相似文献   
122.
123.

Objective

The teaching hospital of Nancy, France, implemented a specific multidisciplinary care pathway (French acronym AMDPL) to improve the management of patients presenting with Lyme borreliosis (LB) suspicion. We aimed to assess the first year of activity of this care pathway.

Patients and methods

We included all patients managed in the AMDPL pathway from November 1, 2016 to October 31, 2017. The first step was a dedicated Lyme disease consultation with an infectious disease specialist. Following this consultation, the LB diagnosis was either confirmed and adequate treatment was prescribed, or a differential diagnosis was established and patients received adequate management, or further investigations were required and patients were offered multidisciplinary management as part of a day hospitalization.

Results

A total of 468 patients were included. LB diagnosis was confirmed in 15% of patients (69/468), 49% of patients received a differential diagnosis, and 26% (122/468) of patients had the LB diagnosis ruled out without receiving any other diagnosis.

Conclusions

This is to our knowledge the first multidisciplinary center implemented in France for the management of patients presenting with LB suspicion related to polymorphous signs and symptoms. Several diagnoses could be confirmed or corrected, although some symptoms and complaints could not be explained. This cohort could improve our knowledge of LB and its differential diagnoses.  相似文献   
124.
125.

Aim

The purpose of this study is to find out whether telephone referral from Primary Health Care to Internal Medicine Consult manages to reduce waiting days as compared to traditional referral. This study also aims to know how acceptable is the telephone referral to general practitioners and their patients.

Design

No blind randomized controlled clinical trial.

Setting

Northern Huelva Health District.

Participants

154 patients.

Interventions

Patients referrals from intervention clinicians were sent via telephone consultation, whereas patients referrals from control clinicians were sent by traditional via.

Measurements

Number of days from referral request to Internal Medicine Consult. Number of telephone and traditional referrals. Number of doctors and patients denied. Denial reasons.

Results

A statistically significant difference was found between groups, with an average of 27 (21-34) days. Among General Practitioners, 8 of the first 58 total doctors after randomization and, subsequently, 6 of the 20 doctors of the test group refused to engage in the trial because they considered “excessive time and effort consuming”. 50% of patients referred by the 14 General Practitioners finally randomized to the intervention group were denied referral by telephone due to patient's complexity.

Conclusions

Telephone referral significantly reduces waiting days for Internal Medicine consult. This type of referral did not mean an “excessive time and effort consuming” to General Practitioners and was not all that beneficial to complex patients  相似文献   
126.
127.
128.
Abstract

This study was undertaken to compare the concentrations of pro- and anti-angiogenic growth factors, nitric oxide (NO) stable metabolites in maternal serum and embryonic left ventricular (LV) isovolumic relaxation time (IRT, ms) during the first trimester in two groups of women: with pregnancy conceived by assisted reproductive technologies (ART, n?=?39) and normally conceived (control group, n?=?68) pregnancy. The concentration of vasoconstrictor endothelin 1 was 45.5 times more in ART than in control group. On the contrary, the concentrations of NO stable metabolites in ART were 1.9 times less than in control women. The assessment of angiogenic suppressors in ART women demonstrates the decrease in s-endoglin concentration was 1.6 times and in soluble receptor to vascular endothelial growth factor concentration was 2.0 times in comparison with control group. There was a significant increase in LV IRT in ART embryos in comparison to control ones. These data suggest significant changes in pro- anti-angiogenic factors balance and increase in vascular impedance in ART-conceived embryos.  相似文献   
129.
130.
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