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   746篇
  免费   28篇
  国内免费   2篇
耳鼻咽喉   3篇
儿科学   36篇
妇产科学   23篇
基础医学   61篇
口腔科学   7篇
临床医学   53篇
内科学   186篇
皮肤病学   13篇
神经病学   37篇
特种医学   9篇
外科学   112篇
综合类   53篇
一般理论   9篇
预防医学   61篇
眼科学   21篇
药学   71篇
肿瘤学   21篇
  2013年   5篇
  2011年   5篇
  2010年   6篇
  2009年   8篇
  2006年   5篇
  2002年   5篇
  2000年   5篇
  1999年   13篇
  1998年   11篇
  1997年   22篇
  1996年   22篇
  1995年   18篇
  1994年   15篇
  1993年   18篇
  1992年   17篇
  1991年   13篇
  1990年   14篇
  1989年   14篇
  1988年   24篇
  1987年   20篇
  1986年   20篇
  1985年   14篇
  1984年   20篇
  1983年   17篇
  1982年   16篇
  1981年   15篇
  1980年   10篇
  1979年   7篇
  1978年   8篇
  1977年   7篇
  1976年   5篇
  1975年   6篇
  1970年   4篇
  1968年   6篇
  1966年   4篇
  1965年   10篇
  1964年   16篇
  1963年   14篇
  1961年   6篇
  1960年   3篇
  1959年   25篇
  1958年   42篇
  1957年   47篇
  1956年   32篇
  1955年   30篇
  1954年   45篇
  1949年   26篇
  1948年   26篇
  1947年   2篇
  1946年   3篇
排序方式: 共有776条查询结果,搜索用时 0 毫秒
1.
2.
3.
4.
5.
Intestinal ischaemia-reperfusion (IR) injury has largely been attributed to cellular necrosis. Apoptosis, a distinct form of cell death has been observed following IR to the brain, heart, adrenals and the kidneys. In order to characterize the role of apoptosis in intestinal IR, small bowel grafts were stored in saline ( n  = 6) or modified University of Wisconsin solution ( n  = 6) at 4 °C for 12 h and reperfused for 6 h in syngeneic rats. Samples of normal, stored and reperfused intestines at 1, 3 and 6 h were analysed by light and electron microscopy. Following reperfusion, there was crypt and villous epithelial apoptosis, loss of crypt and villous structures, and an increase in mucosal inflammatory cell infiltration. Ongoing apoptosis was maximum at 1 h, its degree decreasing with increasing reperfusion intervals. Large numbers of apoptotic bodies dominated the picture from 3 h of reperfusion. This study has demonstrated the induction of apoptosis by intestinal IR injury, which begins within an hour of reperfusion and is probably responsible for the observed crypt and villous loss. This has potential therapeutic implications as, opposed to necrosis, apoptosis is an active process with genetic regulators and biochemical effectors, which can be specifically targeted to prevent or alleviate IR injury.  相似文献   
6.
ABSTRACT. A case of Prader Willi Syndrome who suffered from hypothyroidism is described. This patient on cytogenetic examination was found to have Mosaic 46,XX/46,XX,det(15Kq11.1q11.2) karyotype.  相似文献   
7.
Eighteen men (mean age 27, range 18-30 years) treated for Hodgkin's disease with 6-8 courses of MVPP (Mustine, Vinblastine, Procarbazine and Prednisolone) have had Leydig cell function assessed by their steroidogenic responses to stimulation by a single bolus dose of HCG (1000 units intramuscularly). Normal age-matched men (n = 16) acted as controls. Baseline immunoreactive FSH was markedly raised in the patients (mean 18.1 +/- SD 6.9 vs 2.0 +/- 1.5 IU/l, P less than 0.0001) reflecting damage to the germinal epithelium. Immunoreactive LH was also greater in patients (10.3 +/- 3.9 IU/l) than in controls (3.9 +/- 1.9 IU/l, P less than 0.0001). There were no differences between the baseline testosterone, androstenedione, oestradiol, oestrone and sex hormone binding globulin (SHBG) concentrations. The testosterone/SHBG ratios were similar in the two groups and there was no correlation between baseline LH and testosterone concentrations or testosterone/SHBG ratios. Testosterone, androstenedione, oestradiol and oestrone secretion in response to HCG stimulation were similar at 24 h and 96 h in both groups. In order to explain the paradox of elevated immunoreactive LH in the face of normal testicular steroidogenesis in such patients, LH biological activity (B) as well as LH immunoreactivity (I) and FSH and testosterone were estimated in a second similar group of patients (n = 17, mean age 27, range 17-43 years) and in a further age-matched control group (n = 17). Bioactive and immunoreactive LH levels were significantly increased (P less than 0.005 and P less than 0.001, respectively) in the patient group.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
8.
9.
10.
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