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   275374篇
  免费   16097篇
  国内免费   698篇
耳鼻咽喉   3441篇
儿科学   7895篇
妇产科学   5860篇
基础医学   37612篇
口腔科学   11826篇
临床医学   20573篇
内科学   63447篇
皮肤病学   6725篇
神经病学   23887篇
特种医学   7883篇
外国民族医学   26篇
外科学   35152篇
综合类   1882篇
现状与发展   1篇
一般理论   103篇
预防医学   26541篇
眼科学   5247篇
药学   17694篇
中国医学   1092篇
肿瘤学   15282篇
  2023年   1453篇
  2022年   2280篇
  2021年   5854篇
  2020年   3686篇
  2019年   5520篇
  2018年   8103篇
  2017年   5801篇
  2016年   5650篇
  2015年   6670篇
  2014年   8675篇
  2013年   11351篇
  2012年   19469篇
  2011年   20361篇
  2010年   10134篇
  2009年   8562篇
  2008年   16324篇
  2007年   17035篇
  2006年   16199篇
  2005年   16322篇
  2004年   15242篇
  2003年   13806篇
  2002年   11482篇
  2001年   6790篇
  2000年   7312篇
  1999年   5676篇
  1998年   2090篇
  1997年   1685篇
  1996年   1659篇
  1995年   1437篇
  1994年   1354篇
  1993年   1216篇
  1992年   2909篇
  1991年   2785篇
  1990年   2477篇
  1989年   2470篇
  1988年   2228篇
  1987年   2061篇
  1986年   1952篇
  1985年   1918篇
  1984年   1429篇
  1983年   1139篇
  1982年   708篇
  1981年   655篇
  1980年   645篇
  1979年   1003篇
  1978年   699篇
  1977年   563篇
  1975年   599篇
  1974年   607篇
  1973年   594篇
排序方式: 共有10000条查询结果,搜索用时 359 毫秒
11.
12.
13.
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   
14.
15.
Lasers in Medical Science - Studies reported the harmful effects of 2,4-D on body tissues, provoking changes in the anatomy and physiology of the kidneys, liver, and testicles. Thus, the objective...  相似文献   
16.
17.
18.
19.
The present study aimed at measuring seropositivities for infection by Ascaris suum and Toxocara canis using the excretory/secretory (E/S) antigens from Ascaris suum (AES) and Toxocara canis (TES) within an indigenous population. In addition, quantification of cytokine expressions in peripheral blood cells was determined. A total of 50 Warao indigenous were included; of which 43 were adults and seven children. In adults, 44.1% were seropositive for both parasites; whereas children had only seropositivity to one or the other helminth. For ascariosis, the percentage of AES seropositivity in adults and children was high; 23.3% and 57.1%, respectively. While that for toxocariosis, the percentage of TES seropositivity in adults and children was low; 9.3% and 14.3%, respectively. The percentage of seronegativity was comparable for AES and TES antigens in adults (27.9%) and children (28.6%). When positive sera were analyzed by Western blotting technique using AES antigens; three bands of 97.2, 193.6 and 200.2 kDas were mostly recognized. When the TES antigens were used, nine major bands were mostly identified; 47.4, 52.2, 84.9, 98.2, 119.1, 131.3, 175.6, 184.4 and 193.6 kDas. Stool examinations showed that Blastocystis hominis, Hymenolepis nana and Entamoeba coli were the most commonly observed intestinal parasites. Quantification of cytokines IFN-γ, IL-2, IL-6, TGF-β, TNF-α, IL-10 and IL-4 expressions showed that there was only a significant increased expression of IL-4 in indigenous with TES seropositivity (p < 0.002). Ascaris and Toxocara seropositivity was prevalent among Warao indigenous.  相似文献   
20.
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