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   3100篇
  免费   286篇
  国内免费   2篇
耳鼻咽喉   20篇
儿科学   122篇
妇产科学   81篇
基础医学   419篇
口腔科学   45篇
临床医学   419篇
内科学   660篇
皮肤病学   57篇
神经病学   245篇
特种医学   138篇
外科学   377篇
综合类   61篇
一般理论   2篇
预防医学   323篇
眼科学   26篇
药学   283篇
中国医学   2篇
肿瘤学   108篇
  2023年   15篇
  2021年   40篇
  2020年   30篇
  2019年   35篇
  2018年   53篇
  2017年   36篇
  2016年   44篇
  2015年   64篇
  2014年   79篇
  2013年   103篇
  2012年   145篇
  2011年   116篇
  2010年   74篇
  2009年   72篇
  2008年   122篇
  2007年   141篇
  2006年   151篇
  2005年   116篇
  2004年   119篇
  2003年   131篇
  2002年   122篇
  2001年   99篇
  2000年   110篇
  1999年   103篇
  1998年   52篇
  1997年   84篇
  1996年   51篇
  1995年   48篇
  1994年   50篇
  1993年   50篇
  1992年   87篇
  1991年   68篇
  1990年   76篇
  1989年   78篇
  1988年   63篇
  1987年   52篇
  1986年   65篇
  1985年   55篇
  1984年   42篇
  1983年   30篇
  1982年   21篇
  1981年   24篇
  1980年   26篇
  1979年   31篇
  1978年   24篇
  1977年   23篇
  1976年   21篇
  1975年   17篇
  1974年   13篇
  1966年   12篇
排序方式: 共有3388条查询结果,搜索用时 15 毫秒
151.
152.
153.
154.
Rotator cuff tear: clinical experience with sonographic detection   总被引:5,自引:0,他引:5  
Soble  MG; Kaye  AD; Guay  RC 《Radiology》1989,173(2):319-321
Between June 1986 and April 1988, 86 sonographic examinations of the shoulder were performed on patients suspected of having rotator cuff tears. Major sonographic diagnostic criteria included (a) a well-defined discontinuity usually visible as a hypoechoic focus within the cuff, (b) nonvisualization of the cuff and (c) an echogenic focus within the cuff. Seventy-five patients underwent both sonography and arthrography. Compared with arthrography alone, ultrasound examinations enabled detection of 92% of rotator cuff tears (24 of 26 tears), with a specificity of 84% and a negative predictive value of 95%. Correlation was obtained in 30 of these patients who underwent surgery for rotator cuff tear or other soft-tissue abnormality. In this group, the sensitivity of sonography for detection of a tear was 93%, with a specificity of 73%, while for arthrography sensitivity was 87% and specificity was 100%. These data indicate that sonography is a useful, noninvasive screening procedure for patients suspected of having rotator cuff injury.  相似文献   
155.
The results of this study confirm our previous report of increased androgen receptor expression in livers of female SUAH Wistar rats during development of liver tumours induced by diethylnitrosamine (DENA). In adult female rats not treated with DENA, removal of the ovary increased liver androgen receptor levels but testosterone did not further enhance the androgen receptor status of ovariectomized rats. In normal adult males the testis and/or testosterone maintained high levels of androgen receptors but oestrogen reduced them in castrated rats. Oestrogen receptor levels were not significantly changed in either males or females by gonadectomy. Treatment of female rats with DENA for 10 and 16 weeks increased liver androgen receptors but oestrogen receptors were only reduced by 16 weeks of DENA treatment, whether the rats were intact or ovariectomized. Concentrations of liver androgen receptors were increased in intact and castrated male rats by 10 and 16 weeks of DENA treatment, an increase not seen in the previous experiments. Oestrogen appeared to inhibit both the increases in liver androgen receptor expression and liver tumour development in rats treated with the weakly carcinogenic dose of 10 weeks of DENA. However, the full carcinogenic dose of 16 weeks of DENA increased liver androgen receptors and decreased oestrogen receptors in female rats regardless of sex-steroid status. Development of malignant hepatocellular carcinoma (HCC) was associated with both an increase in liver androgen receptors and a decrease in oestrogen receptors. Maintenance of relatively high levels of liver oestrogen receptors appeared to protect the liver against development of HCC.  相似文献   
156.
157.
158.
L L Phillips  J B Rodgers 《Surgery》1979,86(5):714-721
Three cases of disseminated intravascular coagulation following infusion of ascitic fluid from the peritoneal cavity to the vascular system are reported in patients with hepatic cirrhosis. One of these was treated with intermittent drainage and infusion, and in the other two a LeVeen shunt was used. Studies on the ascitic fluid indicate the presence of a procoagulant material which would appear to be an activator of factor X. Preactivated factor X (Xa) from the fluid and/or a tissue factor activator of factor VII are additional possibilities.  相似文献   
159.
160.
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