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   1005篇
  免费   60篇
  国内免费   18篇
耳鼻咽喉   6篇
儿科学   69篇
妇产科学   11篇
基础医学   303篇
口腔科学   31篇
临床医学   96篇
内科学   168篇
皮肤病学   26篇
神经病学   100篇
特种医学   11篇
外科学   49篇
综合类   82篇
预防医学   41篇
眼科学   8篇
药学   46篇
中国医学   7篇
肿瘤学   29篇
  2023年   6篇
  2022年   7篇
  2021年   27篇
  2020年   29篇
  2019年   18篇
  2018年   17篇
  2017年   25篇
  2016年   23篇
  2015年   23篇
  2014年   24篇
  2013年   63篇
  2012年   28篇
  2011年   24篇
  2010年   26篇
  2009年   23篇
  2008年   33篇
  2007年   29篇
  2006年   45篇
  2005年   30篇
  2004年   14篇
  2003年   38篇
  2002年   21篇
  2001年   21篇
  2000年   15篇
  1999年   18篇
  1998年   19篇
  1997年   15篇
  1996年   22篇
  1995年   23篇
  1994年   15篇
  1993年   29篇
  1992年   18篇
  1991年   24篇
  1990年   20篇
  1989年   20篇
  1988年   15篇
  1987年   19篇
  1986年   17篇
  1985年   27篇
  1984年   17篇
  1983年   22篇
  1982年   30篇
  1981年   21篇
  1980年   17篇
  1979年   12篇
  1978年   11篇
  1977年   14篇
  1976年   8篇
  1974年   10篇
  1968年   3篇
排序方式: 共有1083条查询结果,搜索用时 15 毫秒
21.
Gestational diabetes mellitus (GDM) is associated with an increased risk of having a high-care newborn and has an impact on maternal wellbeing. This study aimed to assess the effect of GDM on the lactoferrin (LF), secretory immunoglobulin A (SIgA), immunoglobulin G (IgG), and immunoglobulin M (IgM) concentrations in early colostrum, colostrum, and transitional milk samples of hyperglycemic (n = 53) and normoglycemic (n = 49) mothers using enzyme-linked immunosorbent assay (ELISA). The concentrations of milk lactoferrin and SIgA, but not IgG and IgM, from hyperglycemic and normoglycemic mothers, showed a similar negative correlation with lactation from the first to the fifteenth day. Apart from early colostral IgG, there were no differences in concentrations of LF and immunoglobulins in milk from hyperglycemic and normoglycemic mothers. For hyperglycemia compensated by diet (GDM G1) or insulin treatment (GDM G2), slight differences were seen for LF and IgG, but not for SIgA and IgM, during an early stage of lactation only. Early colostral IgG and colostral LF of insulin-treated mothers were higher (10.01 ± 4.48 mg/L and 11.50 ± 0.58 g/L, respectively) than for diet-control diabetic mothers (7.65 ± 5.67 mg/L and 8.05 ± 1.38 g/L, respectively). GDM of mothers does not have a significant impact on immunological quality of early milk.  相似文献   
22.
23.
Injury or foreign invasion will instigate a cascade of events directed at eliminating the intruder and augmenting the healing process. This involves the unification of two separate processes (inflammatory and immune processes) to provide an effective host defence. Chemical mediators converge on the site of tissue damage and exert local and distant effects. The immune response is divided into innate and acquired immunity. The immediate, non-specific innate response, combined with the specifically targeted acquired response, provide our major defence mechanisms. Lymphocytes and immunoglobulins are the hallmark of acquired immunity. Regulation of these interlinked systems provide cohesion and a group of soluble proteins called cytokines have a major role. Protective immune mechanisms can sometimes cause detrimental effects to the host. We discuss and classify allergic reactions, in particular, the most severe and potentially life threatening form – anaphylaxis.  相似文献   
24.
Preformed human anti-pig antibodies isolated from perfused pig hearts were used to analyze the binding of various immunoglobulin classes to cultured pig kidney cells. All anti-pig immunoglobulins (i.e., IgG, IgA, and IgM) were localized on the cell surface by the use of an indirect immunofluorescence technique. Anti-pig immunoglobulins also competed for the pig cell surface epitopes with Griffonia simplicifolia lectin (GS-I-B4), which is specific for -galactosyl residues. This study provides further evidence that preformed human antibodies recognizing -glactosyl-containing epitopes (anti-gal antibodies) could be an important factor in hyperacute rejection of pig organs.  相似文献   
25.
对15例急性丙型肝炎和慢性丙型肝炎患者血清Ig及CH50进行测定,急性期患者血清IgG高于对照组,IgM与对照组比较无显著差异:IgA低于对照组。慢性其患者血清IgG和IgM均高于对照组,IgA与对照组比较无显著差异。总补体活性CH50在急性与慢性期均低于对照组。结果显示:丙型肝炎的发病及病情与血清Ig及CH50有关。除了细胞免疫参与丙肝的发病机制外,患者的体液免疫功能也发生改变。这种改变可辅助树  相似文献   
26.
小剂量免疫球蛋白在急性白血病化疗期间防治感染的应用   总被引:1,自引:0,他引:1  
目的探讨小剂量静脉注射免疫球蛋白在急性白血病(AL)化学治疗(化疗)期间防治感染的效果.方法 31例AL患者定期常规标准剂量化疗240次,根据是否应用小剂量静脉注射免疫球蛋白防治感染分成实验组(110次)和对照组(130次).观察2组病例感染发生情况及感染控制时间,判定小剂量静脉注射免疫球蛋白的应用效果.结果实验组感染发生率为41.82%(46/110),对照组为83.08%(108/130),两组比较,P<0.01.结论在AL化疗期间小剂量静脉注射免疫球蛋白有防治感染的作用,且安全.  相似文献   
27.
目的构建表达载体pcDNA3.0-sHLA-A2-IgGl-Fc,为进一步真核表达可溶性HLA-A2-IgG1-Fc蛋白奠定基础。方法从T2细胞中提取总RNA,借助RT-PCR技术扩增包括信号肽的可溶性HLA-A2的cDNA序列并把其插入真核表达载体pcDNA3.0,然后经酶切和测序法鉴定;用PCR的方法从含IgG1-Fc基因的PIG质粒中扩增目的基因IgG1-Fc段,然后经酶切后插入前面构建好的表达载体pcDNA3.0-sHLA-A2中,最后经酶切和测序法鉴定。结果经酶切鉴定及测序分析,证实已将目的基因HLA-A2和IgG1-Fc片段插入载体pcDNA3.0。结论本研究成功构建表达载体pcDNA3.0-sHLA-A2-IgG1-Fc。  相似文献   
28.
Therapeutic approaches for autoimmune diseases are primarily based on suppressive measures that down regulate an over productive immune system. The increasing availability of modern biological therapies has advanced the ability to target and to neutralize essential components of the immune response without experiencing the hazardous adverse effects caused by the traditional immunosuppressants. One of the noticeable examples of this approach is the increasing use of high-dose intravenous immunoglobulin (IVIg). IVIg mechanisms include modulating function of Fc receptors, interference with complement activation and cytokine network, provision of anti-idiotypic antibodies, regulation of cell growth, and effects on of T and B cells. In this review we gather existing information regarding IVIg mechanisms of action, clinical applications and its effects on various conditions.  相似文献   
29.
Abstract

An ELISA assay is described for the measurement of the smIgG. The method is based on the detection of cell-smIgG directly on the same microplate used for the culture. The cells, preincubated at 37°C for one hour, were cultured in the presence of S-ConA and serum-free medium for two days. Using this strategy, the background noise due to non specific adsorbtion of IgG to plastic wells and cytophilic antibodies was eliminated. The cells in the presence of S-ConA and serum-free medium adhered to the plastic wells, and the cell-smIgG were detected using an anti-human IgG covalently linked to alkaline phosphatase or its F(ab')2 fragment. The possibility of measuring the modulation of the expression of the cell-smIgG without any additional manipulation is stressed.  相似文献   
30.
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