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   729篇
  免费   0篇
化学工业   2篇
冶金工业   726篇
自动化技术   1篇
  2004年   1篇
  2003年   1篇
  2000年   1篇
  1999年   16篇
  1998年   228篇
  1997年   104篇
  1996年   75篇
  1995年   45篇
  1994年   43篇
  1993年   40篇
  1992年   2篇
  1991年   12篇
  1990年   12篇
  1989年   11篇
  1988年   11篇
  1987年   10篇
  1986年   8篇
  1985年   8篇
  1983年   1篇
  1982年   3篇
  1981年   3篇
  1980年   7篇
  1979年   1篇
  1978年   5篇
  1977年   16篇
  1976年   62篇
  1975年   1篇
  1965年   1篇
  1955年   1篇
排序方式: 共有729条查询结果,搜索用时 46 毫秒
721.
Glomeruli in Cryostat sections of foetal and adult renal tissues adsorbed sheep erythrocytes sensitized with IgM antibody and human or mouse complement (EAC). Activated complement was essential for the reaction to occur. The receptor had specificity for the C3b fragment of C3 and is probably of protein or glycoprotein nature. Complement receptors in glomeruli may explain the deposition of complement components or complement-containing complexes in immune-complex glomerulonephritis.  相似文献   
722.
723.
The predominant fatty acids (C10-C18) of dermatophytes were investigated by the Landsteiner-Draize test to establish their allergenicity. It was demonstrated that fatty acids can give rise to sensitization of delayed type in guinea pigs. The middle-chain fatty acids (C10-C12) showed a high allergenicity compared to the (C13-C18) acids with moderate to weak contact sensitizing properties. The fatty acids may act as contact sensitizers and, at least sometimes, be responsible for the skin lesions in dermatophytosis.  相似文献   
724.
Persistent, profuse ileostomy diarrhea developed gradually in a patient over a 12-hour period after proctocolectomy for ulcerative colitis. There was no evidence of ileostomy stenosis or dilation of the ileum proximal to the stoma. He was successfully treated with a reverse ileal segment of 10 cm, and gained 14 to 18 kg. ileostomy output became semisolid and decreased from 1,000 to 2,000 ml/day to 600 ml/day. The transit time changed from 12 minutes to 2 1/2 hours. Antiperistaltic segments of intestine prolong transit time and allow for greater absorption. While most patients with ileostomies are not troubled by severe diarrhea, the small proportion who are may be candidates for a reversed ileal segment.  相似文献   
725.
726.
Mouse thymocyte fractions were isolated on the basis of buoyant density in a step-gradient of human serum albumin. These fractions were characterized by cell size, radiosensitivity and hydrocortisone sensitivity, and by labelled precursor incorporation into DNA, RNA and proteins. The relative sedimentation of nucleoids in sucrose gradient was also determined. Large and more radioresistant thymocytes were characterized by an increased rate of DNA repair compared with the fraction of radiosensitive small lymphocytes. Nucleoids prepared from the small thymocyte fraction had greater relative sedimentation rates than those derived from large cells. The response of relative sedimentation of nucleoids from large and small thymocyte fractions to ethidium bromide concentration does not permit a conclusion on different superhelix density for DNA in cells of these fractions. At the same time the estimate of the supercoiled domain size for nucleoids of large and small thymocyte fractions showed that in the more radiosensitive small cells domains of greater size were predominant.  相似文献   
727.
728.
729.
Regardless of the event that stimulates the aggregation of platelets, the receptor alpha(IIb)beta3--one of a family of adhesion receptors known as integrins--has a key role in the process. The past decade has seen the publication of 10 phase III (randomised) clinical trials of four members of a new class of antiplatelet drugs, the GPIIb-IIIa blockers, targeted at this important receptor. Three (abciximab, eptifibatide, and tirofiban) are licensed for human use. 10 other GbIIb-IIIa blockers are in phase II or III human studies. In all 10 placebo-controlled trials, done in the clinical settings of percutaneous coronary intervention or acute coronary syndrome in patients on aspirin, the endpoints favoured the active drug, with a risk reduction for death or non-fatal myocardial infarction of about 21% overall. With attention to heparin dose the risk of bleeding is not a major concern with these agents. The GPIIb-IIIa blockers are taking the clinician and patient out of the era of aspirin monotherapy when platelet inhibition is required.  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