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   221篇
  免费   4篇
  国内免费   26篇
儿科学   14篇
妇产科学   1篇
基础医学   21篇
口腔科学   5篇
临床医学   43篇
内科学   55篇
皮肤病学   4篇
神经病学   3篇
特种医学   52篇
外科学   7篇
综合类   5篇
预防医学   2篇
眼科学   1篇
药学   35篇
中国医学   2篇
肿瘤学   1篇
  2022年   1篇
  2021年   2篇
  2019年   1篇
  2018年   2篇
  2017年   1篇
  2016年   1篇
  2015年   2篇
  2014年   3篇
  2013年   3篇
  2012年   2篇
  2011年   2篇
  2010年   4篇
  2009年   8篇
  2008年   7篇
  2007年   20篇
  2006年   2篇
  2005年   1篇
  2004年   4篇
  2003年   1篇
  2002年   2篇
  2001年   6篇
  1999年   5篇
  1998年   16篇
  1997年   14篇
  1996年   11篇
  1995年   9篇
  1994年   13篇
  1993年   15篇
  1992年   4篇
  1991年   8篇
  1990年   1篇
  1989年   8篇
  1988年   12篇
  1987年   5篇
  1986年   7篇
  1985年   8篇
  1984年   3篇
  1983年   2篇
  1982年   5篇
  1981年   2篇
  1980年   5篇
  1979年   1篇
  1978年   8篇
  1977年   5篇
  1976年   6篇
  1975年   3篇
排序方式: 共有251条查询结果,搜索用时 17 毫秒
41.
盐酸放线瑞香宁(actinodaphine-HCl)系从莲叶桐科青藤属植物黑吹风(Illigera khasiana C.B Clarke)中分离提取而得的有效成分,结构式如图1。药理试验证明有解热、镇痛、解痉等作用。本文报告用紫外二阶导数光谱法研究盐酸放线瑞香宁在兔体内的药代动力学结果。家兔4只,体重2.8±0.6kg。盐酸放线瑞香宁由本所植化室提供。氯仿、乙醇均为A.R。Perkin-Elmer型紫外—可见光分光光度计系美国产品。  相似文献   
42.
Wang  Minjiao  Qian  Yifeng  Zhao  Hanjiang  Zhu  Min  Yu  Hongbo  Shen  Steve GF. 《Clinical oral investigations》2022,26(12):7083-7093
Clinical Oral Investigations - To evaluate postoperative mandibular stability and condylar changes in patients with mandibular hypoplasia and preoperative condylar resorption (CR) undergoing...  相似文献   
43.
44.
Bone scintigraphy in the reflex sympathetic dystrophy syndrome   总被引:1,自引:0,他引:1  
  相似文献   
45.
46.
47.
目的:研究金属硫蛋白(MT)对氧自由基损伤线粒体的保护作用以探讨其细胞保护机制。方法:采用FeSO4/抗坏血酸自由基发生系统直接损伤线粒体,测定Ca(2+)-Mg(2+)-ATPase活性和Ca(2+)摄入的变化。结果:MT能够直接拮抗氧自由基对线粒体Ca(2+)-Mg(2+)-ATPase活性和Ca(2+)摄入的抑制作用(P<0.01)。结论:MT对氧自由基损伤线粒体有明显保护作用,MT对细胞器线粒体的保护作用可能是细胞保护机制之一。  相似文献   
48.
We have previously described a unique type of delta beta-thalassemia in a Chinese family characterized by increased expression of the G gamma and A gamma fetal globin genes in the absence of a large deletion in the beta-globlin gene cluster. Our earlier study of the beta-globin gene on this delta beta-thalassemia chromosome showed a promoter mutation in the TATA box. In this report, we describe the results of our study of the fetal globin domain of this delta beta-thalassemia chromosome. We have cloned a 13-kb DNA fragment that includes the G gamma and the A gamma genes and the 3' A gamma enhancer element of this delta beta-thalassemia chromosome. DNA sequence analysis of the G gamma and A gamma-globin genes including their promoters did not show any mutations, but analysis of the putative enhancer element downstream from the A gamma-globin gene showed a C to T substitution 2,401 nucleotides downstream from the A gamma cap site. We performed DNA linkage analysis to determine if this mutation is unique to this chromosome or represents a common polymorphism. Our linkage analysis showed that this mutation is not a common polymorphism and that it is also not an intrinsic part of the haplotype of the chromosome on which it was found. We also studied the interaction of nuclear proteins from erythroid and nonerythroid cells with the DNA sequences surrounding this mutation. We have shown by in vitro DNase I footprinting that this mutation falls within a region that is occupied by a novel DNA-binding protein that binds to this site in nuclear extracts from erythroid, but not nonerythroid cells. The binding of this nuclear protein to DNA appears to be dependent on GATA-1 binding to an adjacent GATA-1 site. We have also developed a new functional assay to compare the activity of the normal and mutant A gamma enhancer elements in erythroid cells. Analysis of the activity of the mutant enhancer shows that the mutation completely eliminates all enhancer activity in this assay. These findings suggest that this mutation of the A gamma enhancer on a chromosome that carries a partially inactivated beta-globin gene may be responsible for the increased expression of both gamma-globin genes seen in this condition.  相似文献   
49.
50.
Ethylene oxide allergy in dialysis patients   总被引:1,自引:0,他引:1  
DESIGN OF STUDY: Two groups of patients undergoing long-term dialysis were studied in order to evaluate the importance of ethylene oxide (EtO) in causing allergic reactions during dialysis. The first group of 50 subjects had never shown any hypersensitivity reactions related to dialysis, whereas the second group of 20 subjects had previously complained of reactions. All the patients underwent a prick test with a standard kit of aeroallergens in order to assess the presence of atopy (in doubtful cases a RAST test was carried out with the same aeroallergens). A blood sample for the investigation of EtO specific IgE antibodies was taken from all the patients; the immunoenzymatic method was used. RESULTS: Sensitivity to EtO is significantly higher in the group of patients with previous allergic reactions during dialysis (55 vs 6% in the control group).   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