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   1333018篇
  免费   102074篇
  国内免费   4241篇
耳鼻咽喉   16796篇
儿科学   43654篇
妇产科学   36363篇
基础医学   197865篇
口腔科学   35905篇
临床医学   129502篇
内科学   257890篇
皮肤病学   26386篇
神经病学   111897篇
特种医学   48177篇
外国民族医学   367篇
外科学   184021篇
综合类   28763篇
现状与发展   1篇
一般理论   460篇
预防医学   114201篇
眼科学   28964篇
药学   98824篇
  6篇
中国医学   3166篇
肿瘤学   76125篇
  2021年   10888篇
  2019年   11629篇
  2018年   16310篇
  2017年   12290篇
  2016年   13250篇
  2015年   15203篇
  2014年   20809篇
  2013年   32063篇
  2012年   44258篇
  2011年   46900篇
  2010年   27091篇
  2009年   24938篇
  2008年   42736篇
  2007年   45084篇
  2006年   45196篇
  2005年   43621篇
  2004年   41590篇
  2003年   39514篇
  2002年   38332篇
  2001年   60867篇
  2000年   62537篇
  1999年   52303篇
  1998年   14600篇
  1997年   13286篇
  1996年   13121篇
  1995年   12467篇
  1994年   11636篇
  1993年   10927篇
  1992年   41584篇
  1991年   40773篇
  1990年   39457篇
  1989年   37360篇
  1988年   34596篇
  1987年   33704篇
  1986年   32157篇
  1985年   30650篇
  1984年   23039篇
  1983年   19597篇
  1982年   11756篇
  1979年   20808篇
  1978年   14819篇
  1977年   12068篇
  1976年   11878篇
  1975年   12115篇
  1974年   14802篇
  1973年   14473篇
  1972年   13358篇
  1971年   12420篇
  1970年   11487篇
  1969年   10413篇
排序方式: 共有10000条查询结果,搜索用时 672 毫秒
991.
992.
993.
The aim of this research was to assess whether common genetic variants within the C-reactive protein gene ( CRP ) are related to the degree of acute rise in plasma C-reactive protein (CRP) levels following an acute coronary syndrome (ACS). While polymorphisms within CRP are associated with basal CRP levels in healthy men and women, less is known about the relationship of such genetic variants and the degree of CRP rise during and after acute ischemia. Plasma CRP is associated with increased rates of recurrent coronary events. We evaluated seven common genetic variants within CRP and assessed their relationship to the degree of rise in CRP levels immediately following an acute coronary syndrome in 1827 European American patients. Variants in the putative promoter region, −757T > C and −286C > T > A, were associated with the highest CRP elevations after ACS. Patients with two copies of the A allele of SNP −286C > T > A had median CRP values of 76.6 mg/L, compared to 11.1 mg/L in patients with no copies of the rare variant (p-value <0.0001), post ACS. The lowest CRP values were found for patients with minor alleles of the exonic 1059G > C and the 3'untranslated region 1846G > A SNPs. For example, patients homozygous for the minor allele of 1059G > C had 71% lower median CRP values than those homozygous for the major allele [3.5 vs 12.0 mg/L, p < 0.0001]. These trends persisted in the chronic stable phase after ischemia had resolved, and after adjustment for infarct size by peak creatinine kinase levels and clinical status by Killip class. Assessment of CRP genetic variants identified patients with higher and lower CRP elevation after acute coronary syndrome.  相似文献   
994.
995.
996.
997.
998.
The inhibitory effect of polysaccharide on mumps virus multiplication   总被引:12,自引:12,他引:0  
Polysaccharides derived from type-specific Friedl?nder bacilli cause inhibition of the multiplication of mumps virus in the allantoic sac of the chick embryo. As little as 5 microg. of polysaccharide is effective as an inhibitor. Inhibition of multiplication is obtained when polysaccharide is injected as long as 4 days after inoculation of virus. Chemical studies have shown that the structural configurations of the polysaccharide responsible for specific serological activity are not identical with those which determine the inhibitory effect relative to mumps virus. The possible mechanisms of the inhibition of viral multiplication by means of polysaccharides are discussed.  相似文献   
999.
The relationship between the fever of acute infection and that following injection of bacterial pyrogen was studied by administering pyrogens to animals convalescent from acute infections. Rabbits surviving dermal pneumococcal infections or peritonitis due to Escherichia coli were given intravenous injections of typhoid or E. coli vaccine. They showed no evidence of tolerance to the fever-promoting effect of these pyrogenic materials. Tolerance did develop in infected animals given daily pyrogen injections during the course of the infection. Certain previous observations upon the ability of rabbits to develop tolerance to pyrogens, the broad nature of the tolerance, and its duration were confirmed. It is concluded that the pyrogen produced by certain bacteria plays little or no r?le in the production of the fever of infection. These findings are compatible with the hypothesis that there is a common factor, perhaps a product of cell injury, underlying the fever accompanying diseases of various types.  相似文献   
1000.
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