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   8983篇
  免费   860篇
  国内免费   26篇
耳鼻咽喉   60篇
儿科学   321篇
妇产科学   154篇
基础医学   1215篇
口腔科学   213篇
临床医学   1046篇
内科学   1806篇
皮肤病学   115篇
神经病学   614篇
特种医学   358篇
外科学   1430篇
综合类   319篇
一般理论   9篇
预防医学   917篇
眼科学   102篇
药学   584篇
中国医学   39篇
肿瘤学   567篇
  2021年   110篇
  2020年   83篇
  2019年   114篇
  2018年   158篇
  2017年   98篇
  2016年   102篇
  2015年   128篇
  2014年   188篇
  2013年   288篇
  2012年   397篇
  2011年   403篇
  2010年   241篇
  2009年   242篇
  2008年   380篇
  2007年   399篇
  2006年   427篇
  2005年   381篇
  2004年   360篇
  2003年   329篇
  2002年   347篇
  2001年   303篇
  2000年   282篇
  1999年   240篇
  1998年   146篇
  1997年   143篇
  1996年   126篇
  1995年   115篇
  1994年   95篇
  1993年   120篇
  1992年   204篇
  1991年   180篇
  1990年   213篇
  1989年   188篇
  1988年   172篇
  1987年   166篇
  1986年   154篇
  1985年   157篇
  1984年   131篇
  1983年   87篇
  1982年   71篇
  1981年   70篇
  1980年   68篇
  1979年   118篇
  1978年   82篇
  1976年   78篇
  1975年   75篇
  1974年   86篇
  1973年   82篇
  1972年   87篇
  1969年   82篇
排序方式: 共有9869条查询结果,搜索用时 15 毫秒
1.
Cancer Chemotherapy and Pharmacology - Addition of solid doxorubicin or solutions to pre-formed liposomes proved to be the optimal method for incorporating the drug into liposomes whilst...  相似文献   
2.
3.
4.
This study evaluated the effects of tobacco Purchase, Use and Possession (PUP) laws on student perceptions of adolescent tobacco use within towns and schools. Twenty‐four towns were randomly assigned into two conditions, the experimental condition (E PUP) involved efforts to increase both PUP law enforcement and reduce minors' access to commercial sources of tobacco, whereas the control condition (C) focused only on efforts to reduce minors' access to commercial sources of tobacco. A hierarchical linear modeling analytical approach was selected due to the multilevel data and nested design. The present study found that over time, youth in the experimental PUP condition observed less youth tobacco usage at school and in their town, and perceived lower rates of tobacco among their peers at school and among friends than youth in the control condition. The findings suggest that PUP law enforcement might be used to strengthen community norms against youth tobacco use.  相似文献   
5.
6.
7.
R C Hunt  D M Bryan  V S Brinkley  T W Whitley  N H Benson 《JAMA》1991,265(15):1982-1984
This study assessed the capabilities of a traditional and an amplified stethoscope used by flight nurses to assess breath sound during air medical transport in an MBB BO-105 helicopter. We developed a normal breath sound model using a prerecorded tape of breath sounds interspersed with segments without breath sounds; the recorder had been placed in the chest wall of a resuscitation training manikin. Flight nurses completed control listening sessions in a quiet environment and experimental sessions during flight using a traditional stethoscope for half of the sessions and an amplified stethoscope for the remaining half. In the quiet environment, flight nurses accurately reported the presence or absence of breath sounds in 110 (92%) of 120 trials. During helicopter flight, none of the flight nurses heard breath sounds during any of the recorded segments with either the traditional stethoscope or the amplified stethoscope. We conclude that flight nurses are unable to hear normal breath sounds using a traditional or amplified stethoscope during flight in a medically configured MBB BO-105 helicopter. Improved stethoscopes, innovative methods of listening, and reduction of aircraft noise are potential solutions to the problems of breath sound assessment during air medical transport.  相似文献   
8.
9.
10.
Suppurative corneal ulceration in Bangladesh   总被引:8,自引:0,他引:8  
Suppurative keratitis is an important preventable cause of blindness, particularly in the developing world. This study analyses 142 cases of suppurative keratitis referred to Chittagong Eye Infirmary, Bangladesh. Some 53.5% of cases were bacterial and 35.9% were fungal. The five most common pathogens were: Pseudomonas sp. 24%, Streptococcus pneumoniae 17%, Aspergillus sp. 13%, Fusarium sp. 7% and Curvularia sp. 6%. Gram stain and culture results were consistent in 62.6% of cases. Previous antibiotic treatment was a significant factor for failure of culture isolation and less so for Gram stain failure. On Gram stain, 55.9% of pseudomonal cases were missed, but only 2% of fungal cases were missed. Over all, Gram stain had a sensitivity of 62% and positive predictive value of 84% for bacterial cases, and 98% and 94% for fungal cases, respectively. Fungal ulcers were typically filamentous, but an antecedent history of trauma was not common. The most frequent injury was due to rice grains, but the inoculum appeared to be introduced during eye washing with contaminated water. Pseudomonal ulcers occurred most frequently in the monsoon season, and Fusarium cases were seen only in the hot, dry season.  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