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   1877篇
  免费   158篇
  国内免费   6篇
耳鼻咽喉   24篇
儿科学   75篇
妇产科学   17篇
基础医学   245篇
口腔科学   53篇
临床医学   171篇
内科学   317篇
皮肤病学   20篇
神经病学   260篇
特种医学   59篇
外科学   321篇
综合类   30篇
预防医学   221篇
眼科学   45篇
药学   119篇
中国医学   3篇
肿瘤学   61篇
  2021年   27篇
  2018年   35篇
  2017年   24篇
  2016年   30篇
  2015年   32篇
  2014年   45篇
  2013年   58篇
  2012年   72篇
  2011年   78篇
  2010年   44篇
  2009年   32篇
  2008年   75篇
  2007年   75篇
  2006年   64篇
  2005年   57篇
  2004年   63篇
  2003年   56篇
  2002年   44篇
  2001年   50篇
  2000年   64篇
  1999年   42篇
  1997年   19篇
  1995年   25篇
  1994年   21篇
  1993年   18篇
  1992年   35篇
  1991年   32篇
  1990年   31篇
  1989年   39篇
  1988年   28篇
  1987年   30篇
  1986年   38篇
  1985年   43篇
  1984年   29篇
  1983年   32篇
  1982年   20篇
  1980年   21篇
  1979年   29篇
  1978年   33篇
  1977年   20篇
  1976年   20篇
  1975年   25篇
  1974年   20篇
  1973年   28篇
  1971年   18篇
  1969年   25篇
  1968年   18篇
  1967年   20篇
  1921年   23篇
  1920年   21篇
排序方式: 共有2041条查询结果,搜索用时 15 毫秒
91.
92.
We report two new cases of Rothmund-Thomson syndrome which emphasize the less well-known non-dermatological complications, namely: hypodontia, soft tissue contractures, proportionate short stature, hypogonadism, anaemia and osteogenic sarcoma. Genetic analysis of these and previously reported pedigrees supports autosomal recessive inheritance.  相似文献   
93.
Changes in cardiac performance during coronary revascularization surgery were followed in 22 selected patients with normal or mildly impaired left ventricles; vasoactive or inotropic drugs were generally avoided. Arterial pressure, filling pressures, and cardiac output were measured; stroke volume and work were calculated before induction of anesthesia, following sternotomy, soon after discontinuation of extracorporeal circulation, and one hour postoperatively. Induction and sternotomy were associated with a depressant effect on cardiac performance. After extracorporeal circulation, however, cardiac performance recovered, cardiac output increased to 7 +/- 0.5 l/min from a preoperative control of 4.9 +/- 0.3 L/min (p less than 0.002) without an elevation of atrial pressures. This increase in cardiac output after bypass resulted from decreased afterload and increased preload secondary to hemodilution. Cardiac performance approached control values early in the postoperative period.  相似文献   
94.
95.
Early clinical experience with cloth-covered valvular prostheses.   总被引:2,自引:0,他引:2       下载免费PDF全文
R Hodam  A Starr  R Herr    W R Pierie 《Annals of surgery》1969,170(3):471-482
  相似文献   
96.
1. Sodium phenylbutazone, soya bean trypsin inhibitor, or the concomitant administration of ascorbic acid and mepyramine protected rats against anaphylactic shock at 10 days after sensitization but gave no protection against anaphylaxis at 20 days.2. During anaphylactic shock in rats at 10 days after sensitization, the plasma bradykinin and bradykininogen levels, as well as those in the intestinal lumen and peritoneal cavity, were markedly raised.3. The results support the hypothesis that there are two phases in anaphylaxis in the rat-an early phase in which bradykinin is a mediator and against which phenylbutazone or soya bean trypsin inhibitor or the mixture of ascorbic acid and mepyramine, give protection, and a late phase which does not involve bradykinin.  相似文献   
97.
98.
A technique for producing a reliable, clinically applicable, and highly reproducible canine model of nonocclusive mesenteric ischemia was developed. Following left thoracotomy in 10 dogs, a 1 mm diameter soft polyethylene tube was inserted into the pericardial space via a small puncture site. This tube was sealed in place with cyanoacrylate tissue adhesive. A solution of 10% Dextran 40 in saline was infused into the pericardial space until a 50% reduction (as monitored by electromagnetic flowmeter) in superior mesenteric artery flow (SMAQ) was obtained. Without additional intrapericardial infusion of the Dextran solution, SMAQ was reduced 51 +/- 4% to 54 +/- 3% of control values during a 60 minute post-tamponade observation period. During the same time. Cardiac output was depressed between 40 +/- 8% and 54 +/- 3%, and right atrial pressure remained elevated between 164 +/- 15% and 171 +/- 15%. Systemic arterial pressure initially dropped 28 +/- 5% but compensated to within 11 +/- 5% of pre-tamponade level at 60 minutes. The stability of this model is well suited for evaluating new experimental diagnostic and therapeutic procedures.  相似文献   
99.
Auditory brain stem potentials were mapped over the head of the rhesus monkey following monaural clicks. Latency and amplitude were dependent upon the recording site. No electrically indifferent point could be found on the head or neck. The results are interpreted as showing that waves I and V originate from single generators, whereas waves, II, III and IV originate from bilateral structures. Latency varied in a linear fashion with changes in intensity and click rate. In contrast there were variations in amplitude of the potentials independent of stimulus change. A comparison was made of auditory brain stem potentials in man, monkey, cat and rat to demonstrate the similarity of the responses across species.  相似文献   
100.
Five infants with intractable congestive heart failure due to ostium secundum atrial septal defect (ASD) are presented. All survived ASD closure and are doing well. Correction of this defect in infancy should be considered when medical therapy is unsuccessful.  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