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   381898篇
  免费   24319篇
  国内免费   2828篇
耳鼻咽喉   5203篇
儿科学   8337篇
妇产科学   10138篇
基础医学   53371篇
口腔科学   11827篇
临床医学   30396篇
内科学   78796篇
皮肤病学   8635篇
神经病学   27440篇
特种医学   14011篇
外国民族医学   82篇
外科学   61090篇
综合类   10057篇
现状与发展   1篇
一般理论   65篇
预防医学   17679篇
眼科学   9481篇
药学   31134篇
  1篇
中国医学   2206篇
肿瘤学   29095篇
  2021年   2726篇
  2019年   2808篇
  2018年   4598篇
  2017年   3481篇
  2016年   3579篇
  2015年   4095篇
  2014年   5771篇
  2013年   7517篇
  2012年   10190篇
  2011年   10388篇
  2010年   6296篇
  2009年   5952篇
  2008年   9597篇
  2007年   10477篇
  2006年   10387篇
  2005年   9421篇
  2004年   8923篇
  2003年   8662篇
  2002年   8309篇
  2001年   28302篇
  2000年   28816篇
  1999年   23703篇
  1998年   5198篇
  1997年   4287篇
  1996年   3855篇
  1995年   3503篇
  1994年   3120篇
  1993年   2854篇
  1992年   16087篇
  1991年   14844篇
  1990年   14179篇
  1989年   13987篇
  1988年   12598篇
  1987年   12075篇
  1986年   11115篇
  1985年   10331篇
  1984年   6918篇
  1983年   5606篇
  1982年   2723篇
  1979年   5486篇
  1978年   3355篇
  1977年   2975篇
  1975年   2642篇
  1974年   3065篇
  1973年   2867篇
  1972年   2828篇
  1971年   2774篇
  1970年   2511篇
  1969年   2544篇
  1968年   2250篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
Three hours after iv administration of alloxan and 5,6-diamino-2,4-dihydroxy-pyrimidine to mice infected with chloroquine-sensitive (CS) and chloroquine-resistant (CR) strains of Plasmodium berghei, the 2 compounds showed remarkable antimalarial actions. Parasitemia in CS and CR infected mice were reduced by about 50%. Slight hemolysis was seen in mice treated with alloxan but not in mice treated with 5,6-diamino-2,4-dihydro-pyrimidine. Alloxan did not inhibit glutathione reductase activity and no alloxan-glutathione complex was produced. No relationship between the antimalarial effects of alloxan and hemolysis or GSH content were found. It is suggested that the antimalarial effects of the two agents may be due to the inhibition of dihydroorotic acid dehydrogenase.  相似文献   
994.
995.
In this paper, 34 samples, 25 from 18 cervical carcinoma patients and 9 from 8 non-cervical carcinoma patients, were assayed using (alpha-32P) dCTP HSV-2 DNA probe and nucleic acid hybridization technic. It was shown that the positive rates of HSV-2 DNA corresponding sequence were 50% (2/4), 36% (5/14) and 12% (1/8) in the in situ cancer, invasive cancer and non-cervical cancer tissues. No HSV was isolated from 7 cancer specimens which showed a positive reaction by nucleic acid hybridization.  相似文献   
996.
997.
998.
999.
The authors performed dexamethasone suppression tests (DST), TRH infusions, 72-hour urine collections, and lumbar punctures on a group of male depressed patients. Approximately 60% of the patients were DST positive and 33% had a blunted TSH response. Two biologic variables, the 8 a.m. postdexamethasone cortisol and the postprobenecid CSF 5-hydroxyindoleacetic acid (5-HIAA), accounted for over half of the variance in the behavioral measure, the Hamilton score. Plasma cortisol elevation was associated with high 3-methoxy-4-hydroxyphenyl glycol (MHPG) excretion; TSH blunting was associated with low urinary MHPG excretion. Comprehensive biologic measures showed certain significant interrelationships and correlations with the severity of depression.  相似文献   
1000.
Plasma testosterone and estradiol are determined in 72 patients with abnormal high density lipoprotein. cholesterol (HDL-C) and high density lipoprotein cholesterol/total cholesterol (H/T) ratio values, and in 72 randomly chosen males with normal HDLC and H/T values. The results showed that plasma testosterone levels in the groups with abnormal HDL-C and H/T were obviously lower than those in the controls. Statistically significant differences were found in all the abnormal groups in comparison with the controls (P0.20). Testosterone levels lowered further with increasing age in the groups with abnormal HDL-C and H/T., the most obvious drops were in the groups around 56 years of age (P<0.005). The data indicate that male hormone deficiency may reduce HDL-C and H.'T and facilitate the process of atherosclero_is. Therefore, it seems rational to treat such patients with male sex hormone preparations or to use the traditional Chinese medicines which strengthen Yang (maleness) in a new attempt to treat and prevent CHD.  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