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   316832篇
  免费   19497篇
  国内免费   1185篇
耳鼻咽喉   3611篇
儿科学   10202篇
妇产科学   7083篇
基础医学   44505篇
口腔科学   12179篇
临床医学   26915篇
内科学   70257篇
皮肤病学   7588篇
神经病学   29122篇
特种医学   9226篇
外国民族医学   30篇
外科学   34902篇
综合类   2158篇
现状与发展   2篇
一般理论   144篇
预防医学   31725篇
眼科学   5519篇
药学   20871篇
中国医学   1165篇
肿瘤学   20310篇
  2023年   2094篇
  2022年   3929篇
  2021年   8533篇
  2020年   5521篇
  2019年   7774篇
  2018年   9698篇
  2017年   7293篇
  2016年   7497篇
  2015年   8511篇
  2014年   11386篇
  2013年   14722篇
  2012年   22540篇
  2011年   23377篇
  2010年   12357篇
  2009年   10993篇
  2008年   18457篇
  2007年   19071篇
  2006年   17509篇
  2005年   17397篇
  2004年   15997篇
  2003年   14578篇
  2002年   12063篇
  2001年   6185篇
  2000年   5979篇
  1999年   5535篇
  1998年   2739篇
  1997年   2281篇
  1996年   2055篇
  1995年   1751篇
  1994年   1715篇
  1993年   1497篇
  1992年   3306篇
  1991年   3090篇
  1990年   2833篇
  1989年   2807篇
  1988年   2546篇
  1987年   2334篇
  1986年   2216篇
  1985年   2088篇
  1984年   1563篇
  1983年   1308篇
  1982年   835篇
  1981年   725篇
  1980年   707篇
  1979年   1103篇
  1978年   750篇
  1977年   607篇
  1975年   652篇
  1974年   645篇
  1973年   638篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
11.
Neorickettsia helminthoeca (NH), the agent of salmon poisoning disease or canine neorickettiosis (CN), is a bacterial endosymbiont of the nematode Nanophyetus salmincola, and infections are spreading among specific fish‐eating mammalians. This article describes the pathologic and immunohistochemical findings associated with spontaneous NH‐induced infections in dogs from Southern Brazil. The principal pathologic findings were hypertrophy of Peyer patches and lymphadenopathy with lymphocytic proliferation, chronic interstitial pneumonia, and chronic enteritis associated with positive intralesional immunoreactivity to antigens of NH within macrophages and histiocytes. Positive immunoreactivity against canine parvovirus‐2 (CPV‐2) or/and canine distemper virus was not detected in the evaluated intestinal segments or in the samples from the cerebellum and lungs, respectively, from the dogs evaluated. These findings demonstrated that NH was involved in the enteric, pulmonary, and lymphoid lesions herein described, and provide additional information to confirm the occurrence of this bacterial endosymbiont within this geographical location. It is proposed that chronic pneumonia should be considered as a pathologic manifestation of NH‐induced infections. Additionally, our results show that the occurrences of CN seem to be underdiagnosed in Southern Brazil due to the confusion with the incidence of CPV‐2.  相似文献   
12.
13.
14.
Depigmented lesions may occur as postinflammatory sequelae of subacute cutaneous lupus erythematosus (SCLE), leading to great psychosocial impact. A 53‐year‐old male patient presented with post‐SCLE depigmented facial lesions after five years of disease stability. We proposed surgical treatment with melanocyte‐keratinocyte transplantation procedure (MKTP), and after five months the patient achieved 90% repigmentation, without Koebner phenomenon (KP). In theory, KP is a possible complication of MKTP procedure since the preparation of the receptor area involves the use of dermabrasion. In an attempt to avoid it, we suggest to maintain the treatment of the underlying disease and wait for a minimum period of disease stability before the procedure.  相似文献   
15.
16.
17.
18.
19.
20.
In the current immunosuppressive therapy era, vessel thrombosis is the most common cause of early graft loss after renal transplantation. The prevalence of IgA anti–β2-glycoprotein I antibodies (IgA-aB2GPI-ab) in patients on dialysis is elevated (>30%), and these antibodies correlate with mortality and cardiovascular morbidity. To evaluate the effect of IgA-aB2GPI-ab in patients with transplants, we followed all patients transplanted from 2000 to 2002 in the Hospital 12 de Octubre prospectively for 10 years. Presence of IgA-aB2GPI-ab in pretransplant serum was examined retrospectively. Of 269 patients, 89 patients were positive for IgA-aB2GPI-ab (33%; group 1), and the remaining patients were negative (67%; group 2). Graft loss at 6 months post-transplant was significantly higher in group 1 (10 of 89 versus 3 of 180 patients in group 2; P=0.002). The most frequent cause of graft loss was thrombosis of the vessels, which was observed only in group 1 (8 of 10 versus 0 of 3 patients in group 2; P=0.04). Multivariate analysis showed that the presence of IgA-aB2GPI-ab was an independent risk factor for early graft loss (P=0.04) and delayed graft function (P=0.04). There were no significant differences regarding patient survival between the two groups. Graft survival was similar in both groups after 6 months. In conclusion, patients with pretransplant IgA-aB2GPI-ab have a high risk of early graft loss caused by thrombosis and a high risk of delayed graft function. Therefore, pretransplant IgA-aB2GPI-ab may have a detrimental effect on early clinical outcomes after renal transplantation.  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