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   797635篇
  免费   46939篇
  国内免费   1236篇
耳鼻咽喉   10580篇
儿科学   25540篇
妇产科学   19911篇
基础医学   125209篇
口腔科学   21567篇
临床医学   66508篇
内科学   157429篇
皮肤病学   20218篇
神经病学   61575篇
特种医学   26624篇
外国民族医学   191篇
外科学   112373篇
综合类   9787篇
一般理论   195篇
预防医学   64647篇
眼科学   17513篇
药学   60099篇
中国医学   1920篇
肿瘤学   43924篇
  2021年   8422篇
  2019年   8890篇
  2018年   13643篇
  2017年   9376篇
  2016年   9854篇
  2015年   10975篇
  2014年   13704篇
  2013年   21205篇
  2012年   32028篇
  2011年   33522篇
  2010年   18254篇
  2009年   15959篇
  2008年   29850篇
  2007年   31977篇
  2006年   30960篇
  2005年   30387篇
  2004年   28923篇
  2003年   27157篇
  2002年   26289篇
  2001年   31253篇
  2000年   32301篇
  1999年   26995篇
  1998年   7022篇
  1997年   5952篇
  1996年   6189篇
  1995年   5660篇
  1992年   19276篇
  1991年   19596篇
  1990年   19469篇
  1989年   18537篇
  1988年   17172篇
  1987年   16860篇
  1986年   15888篇
  1985年   15061篇
  1984年   11203篇
  1983年   9549篇
  1982年   5350篇
  1979年   10743篇
  1978年   7815篇
  1977年   6649篇
  1976年   6352篇
  1975年   7322篇
  1974年   8740篇
  1973年   8251篇
  1972年   7995篇
  1971年   7713篇
  1970年   7173篇
  1969年   6893篇
  1968年   6409篇
  1967年   5783篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
992.
The first case of a common origin of both the inferior mesenteric and single main renal artery, angiographically documented in a patient with primary ipsilateral ectopic kidney, is reported. Embryologic as well as surgical aspects are mentioned.  相似文献   
993.
Bismuth subnitrate (BSN), a bismuth compound medically used for antidiarrheics, was orally administered to see whether it can reduce CDDP nephrotoxicity or not. Thirteen patients aged 19 approximately 60 with ovarian cancer entered this BSN-CDDP trial. A total of thirty three courses of BSN-CDDP treatment was undergone. BSN was administered orally at a dose of 50 mg/kg for five days before CDDP therapy. CDDP was infused for two hours. No vigorous hydration or diuresis was performed. Only 2,000 ml of saline with 20 mEq per liter of KCl was given for post-hydration. The median dose of CDDP was 100 mg/m2. The renal toxicity of BSN-CDDP treatment was minimum. 82% of the courses at the sixth day after the treatment had creatinine clearance levels which were more than 80% of those before the treatment. But twenty-four hour NAG and beta 2-microglobulin excretion were significantly increased. Bone marrow suppression and gastrointestinal disturbance were commonly observed. The results of our study indicate that BSN pretreatment reduces the renal toxicity of CDDP to some extent.  相似文献   
994.
Our previous work on a social insect model of ethanol-induced behavior focused on behavioral studies of honeybees (Apis mellifera L.). We now investigate the dependence of honeybee blood ethanol concentration on both the amount of ethanol consumed and time elapsed since ingestion. Blood ethanol level was determined using gas chromatograph using hemolymph taken from harnessed bees. Significantly increased levels of ethanol in honeybee hemolymph were detected within 15 min of feeding bees alcohol. Within 30 min, ethanol concentration increased 2.7 times. The concentration of ethanol ingested also had a significant effect on blood ethanol level. However, postfeeding times greater than 30 min did not significantly increase ethanol concentration in bee hemolymph. This study integrates with our behavioral data on the effect of ethanol on honeybees. Our laboratory and field experiments show a correlation between the time frame for behavioral changes and significant increases of blood ethanol levels shown in this study.  相似文献   
995.
Translated from Khimiko-farmatsevticheskii Zhurnal, Vol. 23, No. 11, pp. 1349–1352, November, 1989.  相似文献   
996.
997.
Serum thyroxine concentrations were measured sequentially in eight healthy male volunteers after the oral administration of one of two brand name, commercially available thyroxine tablets. In all cases, levels peaked at 2 hours and did not return to baseline values until 24 hours after dosing. From 2 through 10 hours, statistically significant elevations in serum thyroxine concentrations were observed. Such fluctuations may be important in evaluating laboratory results in patients receiving replacement doses of thyroxine.  相似文献   
998.
999.
1000.
Pneumonia: a deadly disease despite intensive care treatment   总被引:3,自引:0,他引:3  
In a retrospective study of 30 patients with pneumonia treated in the intensive care unit, it was found that cultures from sputum and bronchial secretions did poorly correspond with blood cultures or serological tests. In only 15 of the patients a reliable etiological diagnosis was ever established. Mechanical ventilation was used in 22 patients, usually with a high oxygen need. At the start of this ventilation a significant blood pressure fall and a further pulmonary deterioration was observed. In fatal cases this pulmonary dysfunction was progressive. The overall mortality was 47%. When an FI02 above 0.6 was needed in the ventilator the mortality was 13/14 (93%).  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