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   379178篇
  免费   24187篇
  国内免费   2809篇
耳鼻咽喉   5191篇
儿科学   8203篇
妇产科学   10136篇
基础医学   53141篇
口腔科学   11777篇
临床医学   30101篇
内科学   78287篇
皮肤病学   8552篇
神经病学   27213篇
特种医学   13928篇
外国民族医学   82篇
外科学   60577篇
综合类   9954篇
现状与发展   1篇
一般理论   64篇
预防医学   17435篇
眼科学   9439篇
药学   30987篇
  1篇
中国医学   2200篇
肿瘤学   28905篇
  2021年   2607篇
  2019年   2730篇
  2018年   4526篇
  2017年   3437篇
  2016年   3525篇
  2015年   4019篇
  2014年   5697篇
  2013年   7381篇
  2012年   10025篇
  2011年   10197篇
  2010年   6185篇
  2009年   5840篇
  2008年   9452篇
  2007年   10286篇
  2006年   10213篇
  2005年   9271篇
  2004年   8779篇
  2003年   8511篇
  2002年   8188篇
  2001年   28254篇
  2000年   28799篇
  1999年   23654篇
  1998年   5161篇
  1997年   4249篇
  1996年   3835篇
  1995年   3478篇
  1994年   3104篇
  1993年   2841篇
  1992年   16055篇
  1991年   14814篇
  1990年   14155篇
  1989年   13961篇
  1988年   12579篇
  1987年   12063篇
  1986年   11109篇
  1985年   10324篇
  1984年   6912篇
  1983年   5604篇
  1982年   2719篇
  1979年   5479篇
  1978年   3348篇
  1977年   2972篇
  1975年   2643篇
  1974年   3065篇
  1973年   2871篇
  1972年   2832篇
  1971年   2777篇
  1970年   2518篇
  1969年   2546篇
  1968年   2252篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
52.
53.
54.
With the increased use of indwelling central venous catheters, increasing numbers of cases of Rhodotorula fungemia have been observed in patients with neoplasia and neutropenia. In most patients with catheter-related Rhodotorula fungemia, the condition has been treated with broadspectrum antibiotics. We report two cases of central venous catheter-related Rhodotorula rubra fungemia that occurred in patients with acute myeloblastic leukemia. Both patients were in a state of neutropenia. One patient was treated with amphotericin B and his central venous catheter was removed, but he died of Klebsiella pneumoniae bacteremia. The other patient was treated with amphotericin B and discharged, with a central venous catheter, after recovery from neutropenia. Although the management of catheter-related Rhodotorula fungemia infections remains controversial, resolution of the underlying disease is more important than catheter removal for recovery from Rhodotorula rubra fungemia. Received: August 22, 2001 / Accepted: October 8, 2001  相似文献   
55.
56.
In rodents, chronic estrogenization has been shown to induce degeneration of dendrites and myelin figures in the hypothalamic arcuate nucleus adjacent to peroxidase-positive astrocyte processes. Because in this brain region estradiol is metabolized to 2-hydroxyestradiol (catecholestrogen), we hypothesized that the latter may be oxidized by the astrocytic peroxidase activity to cytotoxic ortho-semiquinones as occurs in peripheral tissues. Cysteamine induces nonenzymatic peroxidase activity in cultured astroglia identical to that observed in vivo. Using electron spin resonance, we demonstrate robust peroxidase-catalyzed oxidation of 2-hydroxyestradiol and dopamine by cysteamine-pretreated astrocyte cultures relative to untreated controls. These results implicate the peroxidase-positive astrocytes in the pathogenesis of estradiol-related hypothalamic damage, parkinsonism, and other free-radical-related neurologic disorders.  相似文献   
57.
A new macrolide antibiotic, clarithromycin (TE-031, A-56268), was studied for its clinical efficacy in the field of pediatrics. Patients treated were infants and children ranging from 2 months to 11 years old suffering from acute bronchitis in 5 cases, acute tonsillitis in 2 cases, Mycoplasma pneumonia in 2 cases, pertussis in 6 cases, scarlatina in 1 case and acute enteritis in 2 cases, a total of 18 cases. TE-031 was administered 19.7-43.5 mg/kg in daily doses and lengths of treatment ranged from 4 to 19 days. As regards to its clinical efficacy, good or excellent results were obtained in all cases: excellent in 11 cases and good in 7 cases. No clinical side effects nor abnormal laboratory test values obviously attributable to TE-031 were observed.  相似文献   
58.
59.
S R Roffler  M H Yu  B M Chen  E Tung  M Y Yeh 《Cancer research》1991,51(15):4001-4007
Pseudomonas exotoxin A (PE) linked to the F(ab')2 fragment of 1H10, a murine monoclonal antibody recognizing a carbohydrate epitope of a glycoconjugate expressed on the surface of human cervical carcinoma tumor cells, was evaluated for in vitro and in vivo activity. PE can kill cells by ADP-ribosylating elongation factor 2 thus inhibiting protein synthesis. Disulfide- as well as thioether-linked immunotoxins (1H10-PE) killed cervical carcinoma cells in vitro and were 20-160 times more inhibitory to target than to control cells. Cell killing was antibody mediated as demonstrated by the reduction of 1H10-PE growth inhibition to target CaSki cells by free 1H10 F(ab')2. In addition, a control antibody immunotoxin was nontoxic to CaSki cells. Thioether-linked 1H10-PE administered either i.v. or i.p. suppressed the growth of established solid s.c. cervical carcinoma tumors xenografted in nude mice for over 30 days. Treatment with antibody alone or a control immunotoxin had no significant effect on tumor growth. Administration of immunotoxin i.p. was associated with less toxicity than administration i.v., but i.v. injections were more effective at suppressing the growth of established solid tumors.  相似文献   
60.
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