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   989篇
  免费   70篇
  国内免费   7篇
耳鼻咽喉   4篇
儿科学   57篇
妇产科学   9篇
基础医学   95篇
口腔科学   29篇
临床医学   163篇
内科学   205篇
皮肤病学   53篇
神经病学   26篇
特种医学   241篇
外科学   49篇
综合类   23篇
预防医学   32篇
眼科学   7篇
药学   40篇
中国医学   5篇
肿瘤学   28篇
  2023年   8篇
  2021年   9篇
  2020年   6篇
  2019年   6篇
  2018年   22篇
  2017年   11篇
  2016年   18篇
  2015年   20篇
  2014年   25篇
  2013年   23篇
  2012年   16篇
  2011年   16篇
  2010年   35篇
  2009年   54篇
  2008年   25篇
  2007年   8篇
  2006年   13篇
  2005年   4篇
  2004年   6篇
  2003年   13篇
  2002年   10篇
  2001年   13篇
  2000年   9篇
  1999年   13篇
  1998年   49篇
  1997年   58篇
  1996年   67篇
  1995年   55篇
  1994年   47篇
  1993年   49篇
  1992年   20篇
  1991年   11篇
  1990年   16篇
  1989年   37篇
  1988年   32篇
  1987年   33篇
  1986年   34篇
  1985年   27篇
  1984年   15篇
  1983年   9篇
  1982年   23篇
  1981年   17篇
  1980年   10篇
  1979年   6篇
  1978年   7篇
  1977年   12篇
  1976年   11篇
  1975年   13篇
  1964年   4篇
  1956年   3篇
排序方式: 共有1066条查询结果,搜索用时 11 毫秒
991.
992.
Esophagitis caused by oral medication   总被引:1,自引:0,他引:1  
  相似文献   
993.
While neurostimulation—stimulation of the nervous system using electrical current—has been used to treat chronic pain, its use treating postsurgical pain has been limited. Here, we report on the clinical application of a novel investigational lead to provide analgesia following total knee arthroplasty. In 5 subjects, leads were inserted percutaneously using ultrasound guidance within 0.5 to 3.0 cm of the femoral and/or sciatic nerve(s). With the delivery of current, pain decreased an average of 63% at rest, with 4 of 5 subjects having relief of > 50%. During passive and active knee flexion, pain decreased an average of 14% and 50%, with 0/3 and 1/2 subjects attaining > 50% relief, respectively. Ultrasound‐guided percutaneous peripheral nerve stimulation may be a practical modality for the treatment of postsurgical pain.  相似文献   
994.
Objective : To examine the utility of notebook computers in the collection of data in large scale surveys.
Methodology : A notebook computer administered survey of health in adolescents was conducted in 1992 using a multi-instrument questionnaire. Students in school years 7,9 and 11 in private and government schools in Melbourne and rural Victoria participated.
Results : Parental consent was obtained with an 83% response rate. Each student answered questions directly onto the computer taking an average of 68 min to complete the highly branched confidential but not anonymous questionnaire. Students were presented with on average 33% of the 897 possible questions. Over 90% of students reported enjoying using the computer. Those who reported answering the questions honestly all the time ranged from 68 to 85%, increasing with grade level.
Conclusions : The use of computers in survey research provides many advantages in data collection including exposure only to relevant questions and the opportunity of asking sensitive questions.  相似文献   
995.
Treatment of hypoplastic anemia in mice with placental transplants   总被引:1,自引:0,他引:1  
Dancis  J; Jansen  V; Brown  GF; Gorstein  F; Balis  ME 《Blood》1977,50(4):663-670
A genetic mutation in mice (W/Wv) causes an autosomal recessive disease characterized by hypoplastic anemia which lasts throughout life. Double- dominant W/Wv anemic mice were sublethally irradiated to facilitate repopulation of marrow with transplanted cells and were injected intravenously with suspensions of 5-10 million placental cells of 15 days gestation derived from normal, isogeneic donors. Red cell counts fell promptly after irradiation and then rose progressively over a period of weeks, reaching normal levels of the nonmutant. Mean corpuscular volume and hemoglobin electrophoresis patterns of red cells in recipient W/Wv mice resembled those of normal donor animals. The therapeutic effect lasted for the duration of the observation period, in some instances over 9 mo. W/Wv mice that were administered Hanks' solution or fetal blood, instead of placental transplants, remained anemic. Late gestation placentas (18 days) were also ineffective.  相似文献   
996.
Flux cored solder commonly used in the electronics industry is a metal alloy, based on tin and lead, and a flux consisting of colophony with a small concentration of an activator. Thirty-four electronics workers with occupational asthma and seventeen with respiratory symptoms, probably from other causes, have been investigated by occupational type bronchial provocation testing. All the sensitized workers had a significant fall in FEV1 after exposure to colophony fumes for 15 min or less. The non-sensitized workers had no significant reactivity to this test. There was little correlation between the reaction to colophony fumes and the non specific reactivity to histamine, suggesting that colophony fumes were causing specific sensitization. In sensitized workers Portuguese Y colophony was found to cause slightly larger reactions than similar exposures to American WW colophony. In the six workers tested reactions followed exposure to abietic acid alone, the principal resin acid in colophony. Methyhlation of the carboxyl group of colophony was associated with decreased reactivity. Workers with non-specific bronchial hyperreactivity also sometimes reacted after exposure to fumes from the flux activators alone, but even this reaction could show specificity for the specific activator to which the worker was exposed. Finally two non-colophony substitute materials were evaluated.  相似文献   
997.
998.
To determine if magnetic resonance imaging with Gd-DTPA could be used to assess renal and hepatic perfusion and possibly function, a fast-field-echo technique was used to perform sequential imaging of the kidney and liver of five subjects. Sixteen 3-second images of the same section were obtained at 13-second intervals immediately after Gd-DTPA administration, and again at 30 or 50 minutes after injection. From these images, curves of renal and hepatic signal versus time were generated. In each case the renal signal intensity peaked within 2 minutes and decreased to 60% or less by 3.4 minutes, and 35% or less by 50 minutes. Hepatic curves peaked within 2 minutes and approached initial levels by 30 minutes. These results suggest that transit and clearance of the contrast agent can be imaged by this technique.  相似文献   
999.
1000.
A case of autoimmune hemolytic anemia (AIHA) in a young child is described. The hemolysis was resistant to steroid therapy but responded to splenectomy and intravenous immunoglobulin. The autoantibody was shown to be anti-Sc1 by both serologic and immunoblotting techniques. This seems to be the first report of an autoanti-Sc1 detected by immunoblotting and the first example of AIHA in a child caused by autoanti-Sc1.  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