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   13772篇
  免费   979篇
  国内免费   152篇
耳鼻咽喉   94篇
儿科学   482篇
妇产科学   410篇
基础医学   1842篇
口腔科学   295篇
临床医学   1232篇
内科学   2680篇
皮肤病学   226篇
神经病学   929篇
特种医学   575篇
外科学   2316篇
综合类   630篇
一般理论   4篇
预防医学   753篇
眼科学   344篇
药学   803篇
  1篇
中国医学   78篇
肿瘤学   1209篇
  2023年   135篇
  2022年   184篇
  2021年   345篇
  2020年   239篇
  2019年   309篇
  2018年   344篇
  2017年   267篇
  2016年   296篇
  2015年   359篇
  2014年   465篇
  2013年   568篇
  2012年   873篇
  2011年   926篇
  2010年   573篇
  2009年   507篇
  2008年   732篇
  2007年   712篇
  2006年   726篇
  2005年   711篇
  2004年   679篇
  2003年   601篇
  2002年   565篇
  2001年   523篇
  2000年   421篇
  1999年   372篇
  1998年   148篇
  1997年   144篇
  1996年   127篇
  1995年   109篇
  1994年   97篇
  1993年   73篇
  1992年   170篇
  1991年   154篇
  1990年   168篇
  1989年   178篇
  1988年   156篇
  1987年   151篇
  1986年   122篇
  1985年   96篇
  1984年   61篇
  1983年   51篇
  1982年   31篇
  1981年   47篇
  1980年   41篇
  1979年   54篇
  1978年   41篇
  1977年   34篇
  1976年   34篇
  1975年   32篇
  1973年   26篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.
Following an encephalopathic illness, a 13-year-old Chinese boy had a partial form of Klüver-Bucy syndrome with emotional disturbance, recent memory loss, hypersexuality, and polyphagia. Other unusual features included narcolepsy, polydipsia, and polyuria. Virologic studies failed to incriminate the etiologic agent, including herpes simplex virus. Brain biopsy of the frontal lobe demonstrated Alzheimer type II astrocytosis.  相似文献   
3.
A randomly selected sample of 662 12-year-old Hong Kong children, 529 of whom were Southern Chinese and 133 non-Chinese, was clinically examined for dental caries. The DMFT values were 2.76 and 1.66 for the Chinese and non-Chinese children, respectively. The D component for the Chinese children was 2.12, while for the non-Chinese children it was only 0.45. Approximately 24.0% of the Chinese children had attended the dentist because they were in pain. Only 3.8% of the Chinese children had sought orthodontic or preventive treatment, compared with 24.0% of the non-Chinese children. Although these findings indicate the caries experience to be well below the FDI/WHO global goal for the year 2000, there is a great need to increase the level of dental awareness among Chinese children.  相似文献   
4.
5.
6.
Background : Electrohydraulic lithotripsy (EHL) has been available for endoscopic treatment of urinary calculi since 1960, but the large probe size and concerns regarding safety had previously restricted its use to the treatment of bladder calculi. However, recent refinements have made it particularly suitable for the treatment of ureteric calculi. Methods : The authors report their initial experience using EHL in conjunction with mini-ureteroscopy in the treatment of 94 ureteric calculi in 89 patients. The size of the calculi ranged from 3 to 19 mm in diameter, with a mean of 8.2 mm. The mean operating time was 29 min, ranging from 10 to 120 min. Results : A complete fragmentation rate of 91.5% of the calculi was achieved. There were no major complications and a low incidence of minor complications: haematuria (2.2%), urinary tract infection (3.4%) and postoperative ureteric colic (2.2%). There were four cases of minor ureteric perforations (4.5%); all were successfully treated using conservative measures. Conclusions : It is concluded that EHL is a safe and effective method of treating ureteric calculi.  相似文献   
7.
8.
9.
Chronic inflammatory bowel diseases in Singapore   总被引:2,自引:0,他引:2  
  相似文献   
10.
PURPOSE: Type I IFNs (IFN-alpha/beta) have shown significant antitumor activity in preclinical models but limited efficacy and significant toxicity in clinical trials. We hypothesized that the antitumor activity of type I IFNs could be enhanced by chronic, low-dose systemic delivery and sought to test this in murine neuroblastoma models. EXPERIMENTAL DESIGN: Continuous liver-generated expression of human IFN-beta (hINF-beta) was achieved through a gene therapy-mediated approach using adeno-associated virus vectors encoding hIFN-beta (AAV hINF-beta). Orthotopic localized retroperitoneal and disseminated models of neuroblastoma were established using three different xenografts. Immunohistochemical analysis and ELISA were used to evaluate the antiangiogenic effect of therapy. RESULTS: The development of both localized orthotopic (retroperitoneal) and disseminated neuroblastoma was prevented in all mice expressing hINF-beta. Continued growth of established retroperitoneal tumors, treated with AAV hINF-beta as monotherapy, was significantly restricted, and survival for mice with established, disseminated disease was significantly prolonged following administration of AAV hINF-beta. Analysis of treated tumors revealed a significant antiangiogenic effect. Mean intratumoral vessel density was diminished and expression of the angiogenic factors vascular endothelial growth factor and basic fibroblast growth factor were both decreased. Finally, combination therapy in which AAV hIFN-beta was used together with low-dose cyclophosphamide resulted in regression of both established retroperitoneal and disseminated disease. CONCLUSIONS: AAV-mediated delivery of hIFN-beta when used as monotherapy was able to restrict neuroblastoma growth due in part to inhibition of angiogenesis. When used in combination with conventional chemotherapy, AAV hIFN-beta was able to effect complete tumor regression.  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