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   8622篇
  免费   825篇
  国内免费   29篇
耳鼻咽喉   59篇
儿科学   268篇
妇产科学   153篇
基础医学   1176篇
口腔科学   213篇
临床医学   1116篇
内科学   1773篇
皮肤病学   90篇
神经病学   602篇
特种医学   383篇
外科学   1353篇
综合类   209篇
一般理论   9篇
预防医学   882篇
眼科学   98篇
药学   554篇
肿瘤学   538篇
  2021年   97篇
  2019年   104篇
  2018年   144篇
  2017年   90篇
  2016年   92篇
  2015年   106篇
  2014年   162篇
  2013年   275篇
  2012年   363篇
  2011年   375篇
  2010年   193篇
  2009年   226篇
  2008年   371篇
  2007年   387篇
  2006年   396篇
  2005年   367篇
  2004年   348篇
  2003年   317篇
  2002年   347篇
  2001年   302篇
  2000年   287篇
  1999年   232篇
  1998年   141篇
  1997年   122篇
  1996年   112篇
  1995年   112篇
  1994年   85篇
  1993年   114篇
  1992年   202篇
  1991年   179篇
  1990年   211篇
  1989年   190篇
  1988年   177篇
  1987年   164篇
  1986年   147篇
  1985年   163篇
  1984年   131篇
  1983年   93篇
  1982年   81篇
  1981年   74篇
  1980年   74篇
  1979年   116篇
  1978年   89篇
  1977年   71篇
  1976年   79篇
  1975年   75篇
  1974年   86篇
  1973年   82篇
  1972年   87篇
  1969年   81篇
排序方式: 共有9476条查询结果,搜索用时 218 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.
Coronary artery bypass grafts: visualization with MR imaging   总被引:1,自引:0,他引:1  
Gomes  AS; Lois  JF; Drinkwater  DC  Jr; Corday  SR 《Radiology》1987,162(1):175
  相似文献   
7.
Hysterosalpingography was performed in 31 patients by means of a low-dose scanning-beam digital radiographic system. The technique permits adequate evaluation of gynecologic abnormalities while allowing significant reduction in radiation: 2.4-mR (6.1 X 10(-7) C/kg) exposure to the skin and 0.7-mrad (7 X 10(-6) Gy) mean dose to the ovaries per image obtained. Sixteen patients demonstrated readily recognizable and documented abnormalities, corroborated by laparoscopy, laparotomy, or other supportive evidence.  相似文献   
8.
9.
10.
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   
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