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   2391篇
  免费   186篇
  国内免费   8篇
耳鼻咽喉   12篇
儿科学   74篇
妇产科学   23篇
基础医学   394篇
口腔科学   34篇
临床医学   236篇
内科学   525篇
皮肤病学   57篇
神经病学   269篇
特种医学   56篇
外科学   275篇
综合类   30篇
预防医学   143篇
眼科学   50篇
药学   207篇
中国医学   18篇
肿瘤学   182篇
  2023年   19篇
  2022年   28篇
  2021年   59篇
  2020年   41篇
  2019年   45篇
  2018年   66篇
  2017年   54篇
  2016年   58篇
  2015年   56篇
  2014年   87篇
  2013年   105篇
  2012年   149篇
  2011年   190篇
  2010年   108篇
  2009年   80篇
  2008年   143篇
  2007年   166篇
  2006年   136篇
  2005年   153篇
  2004年   136篇
  2003年   145篇
  2002年   121篇
  2001年   35篇
  2000年   32篇
  1999年   39篇
  1998年   31篇
  1997年   19篇
  1996年   13篇
  1995年   20篇
  1994年   16篇
  1993年   11篇
  1992年   25篇
  1991年   17篇
  1990年   14篇
  1989年   14篇
  1988年   25篇
  1987年   13篇
  1986年   10篇
  1985年   11篇
  1984年   7篇
  1983年   9篇
  1982年   7篇
  1981年   5篇
  1980年   4篇
  1977年   7篇
  1975年   4篇
  1973年   6篇
  1972年   6篇
  1971年   6篇
  1970年   5篇
排序方式: 共有2585条查询结果,搜索用时 31 毫秒
61.
A major problem in chronic hepatitis B virus (HBV) infection is that treatment with specific antivirals is life-long since they rarely induce a sustained response. An attractive option is therefore to combine antiviral therapy with some type of immune stimulator, such as a therapeutic vaccine. Several lines of evidence suggest that a key target for the cellular immune response is the HBV core antigen (HBcAg). However, it may also be of advantage to simultaneously improve the neutralizing antibody response to the surface (S) region of HBV. We therefore generated chimeric HBcAg particles expressing preS1 residues 1-42 at the tip of the spike region. We could show that this chimeric HBcAg-preS1 protein primed both HBcAg-specific T cells and antibodies to preS1. This strongly suggests that this may be a viable approach to develop an effective bi-functional therapeutic vaccine as an add-on for the treatment of chronic HBV infections.  相似文献   
62.
63.
64.
65.
66.
DNA methylation and BLC-2 are potential therapeutic targets in acute myeloid leukemia (AML). We investigated pharmacologic interaction between the DNA methyltransferase inhibitor 5-azacytidine (5-AZA) and the BCL-2 inhibitor ABT-737. Increased BCL-2 expression determined by reverse phase protein analysis was associated with poor survival in AML patients with unfavorable cytogenetics (n?=?195). We found that 5-AZA, which itself has modest apoptotic activity, acts synergistically with ABT-737 to induce apoptosis. The 5-AZA/ABT-737 combination enhanced mitochondrial outer membrane permeabilization, as evidenced by effective conformational activation of BAX and ?ψm loss. Although absence of p53 limited apoptotic activities of 5-AZA and ABT-737 as single agents, the combination synergistically induced apoptosis independent of p53 expression. 5-AZA down-regulated MCL-1, known to mediate resistance to ABT-737, in a p53-independent manner. The 5-AZA/ABT-737 combination synergistically induced apoptosis in AML cells in seven of eight patients. 5-AZA significantly reduced MCL-1 levels in two of three samples examined. Our data provide a molecular rationale for this combination strategy in AML therapy.  相似文献   
67.
This paper demonstrates a new and simplified configuration for capillary electrophoresis-amperometric detection (CE-AD) using a paper microfluidic chip incorporating inexpensive wax printing and screen printing based methods and then used for electrophoretic separation and simultaneous in-channel amperometric detection of three clinically relevant neurochemicals in a single run without using any decouplers. Detection of neurochemicals e.g., dopamine, epinephrine and serotonin is crucial for early prediction of neurological disorders including Parkinson''s, Alzheimer''s, dementia, as well as progressive neuro-psychiatric conditions such as depression, anxiety, as well as certain cardiovascular diseases. The plasma concentrations of such neurochemicals are as important as those present in cerebrospinal fluid (CSF) and can be useful for rapid and convenient biosensing. However, simultaneous detection of such neurochemicals in a complex mixture such as human serum requires their separation prior to detection. With the developed microchip, separation and detection of the neurochemicals were exhibited within 650 seconds without pre-treatment and the procedure was validated with spiked fetal bovine serum samples. Beside this, the developed paper microfluidic chip has potential to be integrated in point-of-care diagnosis with onsite detection ability. Moreover, the use of a straight channel capillary, a screen-printed carbon electrode without decoupler, in-channel amperometric detection and low sample volume requirements (2 μL) are shown as additional advantages.

This paper demonstrates a simplified configuration for capillary electrophoresis-amperometric detection using paper microfluidic chip for separation and simultaneous detection of three clinically relevant neurochemicals without using any decouplers.  相似文献   
68.
69.
We present a granulomatous inflammatory tumour of the hand in a fit 26-year-old man. The lesion resolved spontaneously within a month of presentation. Whilst the true nature of this inflammatory lesion remains unknown the case highlights the importance of thorough investigation of all deep-seated soft tissue tumours of the hand prior to committing a patient to surgery.  相似文献   
70.
INTRODUCTIONThis case report outlines the investigation and management of a young patient presenting with left iliac fossa pain and sepsis. A CT was performed which was initially reported as not showing a perforation, however closer analysis provided evidence of subcutaneous emphysema in the anterior abdominal wall. This evidence justified urgent operative intervention. We review the evidence with regard to this presentation.PRESENTATION OF CASEA previously fit 24-year-old male presented with left iliac fossa pain and features of sepsis. A CT provided subtle but distinctive evidence of retroperitoneal perforation secondary to diverticulitis, in the form of surgical emphysema in the anterior abdominal wall. In view of this, urgent operation was considered justified on suspicion of visceral perforation. A diverticular perforation was confirmed intra-operatively, and a sigmoid colectomy with primary anastomosis was performed, together with a covering ileostomy. The patient made a good post-operative recovery.DISCUSSIONDiverticular disease and its complications are becoming more common in a younger age group, in whom perforation may present late or may not be suspected. In this context special attention must be paid to any radiological evidence of perforation.CONCLUSIONSurgical emphysema in the abdominal wall is an indicator of retroperitoneal perforation, and its presence should be excluded before the possibility of perforation is dismissed. This may be of especial value in younger age groups amongst whom perforation may be less clinically obvious.  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