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   6326篇
  免费   294篇
  国内免费   37篇
耳鼻咽喉   174篇
儿科学   124篇
妇产科学   265篇
基础医学   705篇
口腔科学   52篇
临床医学   454篇
内科学   2017篇
皮肤病学   47篇
神经病学   524篇
特种医学   268篇
外科学   655篇
综合类   41篇
一般理论   1篇
预防医学   315篇
眼科学   116篇
药学   560篇
中国医学   3篇
肿瘤学   336篇
  2024年   2篇
  2023年   31篇
  2022年   181篇
  2021年   415篇
  2020年   114篇
  2019年   191篇
  2018年   226篇
  2017年   154篇
  2016年   156篇
  2015年   202篇
  2014年   246篇
  2013年   318篇
  2012年   548篇
  2011年   536篇
  2010年   292篇
  2009年   196篇
  2008年   343篇
  2007年   395篇
  2006年   447篇
  2005年   384篇
  2004年   401篇
  2003年   343篇
  2002年   287篇
  2001年   23篇
  2000年   12篇
  1999年   36篇
  1998年   25篇
  1997年   20篇
  1996年   17篇
  1995年   16篇
  1994年   10篇
  1993年   14篇
  1992年   9篇
  1991年   9篇
  1989年   5篇
  1987年   3篇
  1986年   5篇
  1985年   3篇
  1984年   3篇
  1983年   4篇
  1981年   4篇
  1980年   2篇
  1979年   2篇
  1978年   2篇
  1974年   2篇
  1973年   2篇
  1970年   5篇
  1969年   5篇
  1968年   4篇
  1965年   2篇
排序方式: 共有6657条查询结果,搜索用时 265 毫秒
81.
AIM: To investigate the indications and outcomes of liver transplantation for hepatic epithelioid hemangioendothelioma (HEHE).METHODS: Between 1989 and August 2013, in the Department of General, Transplant, and Liver Surgery, Medical University of Warsaw, 1306 orthotopic liver transplantations (OLTx) were performed, including 72 retransplantations. Unresectable HEHE was an indication for OLTx in 10 patients (0.8% of primary OLTx), the mean age of the patients was 40.5 ± 13.3 years (range 23-65 years), and the male-to-female ratio was 2:8. Kaplan-Meier survival analysis in HEHE, hepatocellular carcinoma (HCC), and other OLTx recipients groups was performed. The differences in mortality were compared using the χ2 test. A P-value < 0.05 indicated statistical significance.RESULTS: No concomitant liver disease was found in any patient. There was no neoadjuvant chemotherapy or radiotherapy. Liver function test results were normal in most of the patients. The levels of alpha-fetoprotein, carcinoembryonic antigen, and carbohydrate antigen 19-9 were normal. In immunohistochemical staining, the neoplastic cells were positive for factor VIII-related antigen, CD31, and CD34, which are endothelial cell markers, and negative for cytokeratin 19, cytokeratin 7, and HepPar-1. Nine patients were alive without tumor recurrence. One patient died 2 mo after OLTx due to septic complications. No morbidity was observed. Maximum follow-up was 11.4 years, with a minimum of 1 mo. The cumulative survival rate at the end of follow-up in HEHE patients was 87.5% compared with 54.3% in the HCC group and 76.3% in the other OLTx recipients group (χ2 test = 1.784, df = 2, P = 0.409).CONCLUSION: Unresectable HEHE, without extrahepatic metastases is an excellent indication for liver transplantation. Long-term survival is very good and much better than in HCC patients and the entire group of OLTx patients.  相似文献   
82.
83.
84.
In recent years much research in RNA nanotechnology has been directed to develop an efficient and clinically suitable delivery system for short interfering RNA (siRNA). The current study describes the in vivo siRNA delivery using PEGylated antibody-targeted SAINT-based-lipoplexes (referred to as antibody-SAINTPEGarg/PEG2%), which showed superior siRNA delivery capacity and effective down-regulation of VE-cadherin gene expression in vitro in inflammation-activated primary endothelial cells of different vascular origins. PEGylation of antibody-SAINTPEGarg resulted in more desirable pharmacokinetic behavior than that of non-PEGylated antibody-SAINTPEGarg. To create specificity for inflammation-activated endothelial cells, antibodies against vascular cell adhesion molecule-1 (VCAM-1) were employed. In TNFα-challenged mice, these intravenously administered anti-VCAM-1-SAINTPEGarg/PEG2% homed to VCAM-1 protein expressing vasculature. Confocal laser scanning microscopy revealed that anti-VCAM-1-SAINTPEGarg/PEG2% co-localized with endothelial cells in lung postcapillary venules. Furthermore, they did not exert any liver and kidney toxicity. Yet, lack of in vivo gene silencing as assessed in whole lung and in laser microdissected lung microvascular segments indicates that in vivo internalization and/or intracellular trafficking of the delivery system and its cargo in the target cells are not sufficient, and needs further attention, emphasizing the essence of evaluating siRNA delivery systems in an appropriate in vivo animal model at an early stage in their development.  相似文献   
85.
Transferrin (Tf) is a glycoprotein responsible for iron transport in the human body. Physiologically in reaction with Concanavalin A, Tf occurs in four distinct variants Tf1, Tf2, Tf3 (apo-Tf) and Tf4. It was reported recently that Tf is changing, particularly during acute phase response, taking place among others in end-stage renal disease. In this study, we wanted to find the answer to three main questions: firstly, how Tf is changing in patients treated with maintenance haemodialysis (mHD), secondly, whether there are any Tf changes in the course of mHD treatment, and thirdly, what factors can affect Tf microheterogeneity in these patients. Studies were performed on 80 haemodialysed patients and 21 healthy volunteers. The Tf concentration was determined by the rocket immunoelectrophoresis, and its microheterogeneity was assessed by the ConA crossed immunoaffinity electrophoresis. During the annual observation of the distribution of the Tf variants, we have found both changes of the percentage contents of all Tf variants in the whole Tf concentration and a significant decrease in Tf2, Tf3 and Tf4 serum concentrations. Moreover, we found that decrease in the renal function, duration of mHD, and inflammation may contribute to these above-mentioned changes, which are probably the factors that should be taken into account when explaining the mechanisms of persistence of anaemia in haemodialysed patients.  相似文献   
86.
87.
88.
89.
90.
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