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   37763篇
  免费   2215篇
  国内免费   195篇
耳鼻咽喉   531篇
儿科学   846篇
妇产科学   748篇
基础医学   5174篇
口腔科学   2120篇
临床医学   2834篇
内科学   9017篇
皮肤病学   928篇
神经病学   3047篇
特种医学   948篇
外科学   5234篇
综合类   175篇
现状与发展   1篇
一般理论   7篇
预防医学   3489篇
眼科学   630篇
药学   2263篇
中国医学   230篇
肿瘤学   1951篇
  2023年   325篇
  2022年   601篇
  2021年   1505篇
  2020年   789篇
  2019年   1261篇
  2018年   1516篇
  2017年   947篇
  2016年   1001篇
  2015年   1150篇
  2014年   1531篇
  2013年   2002篇
  2012年   3083篇
  2011年   3201篇
  2010年   1762篇
  2009年   1504篇
  2008年   2403篇
  2007年   2379篇
  2006年   2161篇
  2005年   2049篇
  2004年   1675篇
  2003年   1550篇
  2002年   1395篇
  2001年   486篇
  2000年   401篇
  1999年   427篇
  1998年   246篇
  1997年   211篇
  1996年   183篇
  1995年   156篇
  1994年   146篇
  1993年   114篇
  1992年   200篇
  1991年   177篇
  1990年   121篇
  1989年   131篇
  1988年   119篇
  1987年   90篇
  1986年   111篇
  1985年   96篇
  1984年   90篇
  1983年   61篇
  1982年   54篇
  1981年   58篇
  1980年   53篇
  1979年   76篇
  1978年   59篇
  1977年   43篇
  1976年   57篇
  1974年   41篇
  1969年   41篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
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   
6.
7.
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   
8.
9.
Obesity Surgery - Laparoscopic sleeve gastrectomy (LSG) is increasingly playing a key role in obesity management. Such operations, however, carry complications sometimes including leaks. The...  相似文献   
10.
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