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   837篇
  免费   22篇
  国内免费   17篇
耳鼻咽喉   1篇
儿科学   31篇
妇产科学   2篇
基础医学   387篇
口腔科学   6篇
临床医学   43篇
内科学   100篇
皮肤病学   10篇
神经病学   23篇
特种医学   8篇
外科学   57篇
综合类   104篇
预防医学   26篇
眼科学   5篇
药学   33篇
中国医学   14篇
肿瘤学   26篇
  2023年   3篇
  2022年   5篇
  2021年   4篇
  2020年   4篇
  2019年   17篇
  2018年   18篇
  2017年   14篇
  2016年   11篇
  2015年   10篇
  2014年   52篇
  2013年   31篇
  2012年   26篇
  2011年   55篇
  2010年   35篇
  2009年   33篇
  2008年   22篇
  2007年   26篇
  2006年   35篇
  2005年   26篇
  2004年   39篇
  2003年   30篇
  2002年   39篇
  2001年   31篇
  2000年   28篇
  1999年   19篇
  1998年   14篇
  1997年   6篇
  1996年   12篇
  1995年   15篇
  1994年   9篇
  1993年   19篇
  1992年   9篇
  1991年   7篇
  1990年   3篇
  1989年   8篇
  1988年   6篇
  1987年   3篇
  1986年   7篇
  1985年   40篇
  1984年   21篇
  1983年   23篇
  1982年   17篇
  1981年   18篇
  1980年   11篇
  1979年   4篇
  1978年   4篇
  1977年   4篇
  1976年   1篇
  1975年   1篇
  1970年   1篇
排序方式: 共有876条查询结果,搜索用时 0 毫秒
1.
Drosophila has been increasingly used as a model to study hemolymph clotting. Proteomics and bioinformatics identified candidate clotting-factors, several of which were tested using genetics. Mutants and lines with reduced expression of clotting-factors show subtle effects after wounding, indicating that sealing wounds may rely on redundant mechanisms. More striking effects are observed after infection, in particular when a natural infection model involving entomopathogenic nematodes is used. When translated into mammalian models these results reveal that mammalian blood clots serve a similar immune function, thus providing a new example of the usefulness of studying invertebrate models.  相似文献   
2.
本文的主要目的是采用直接免疫荧光法检测SS患者唇腺组织中免疫球蛋白(Ig)和C_3的含量和定位,并对其结果进行分析,试图为探讨SS的病发机理提供依据。  相似文献   
3.

Purpose

The objective of this study was to evaluate thevitamin D concentration in patients with recurrent respiratory infections with or without immunoglobulin G, A or M (IgG, IgA, IgM) deficiency, and to find a correlation between the vitamin D concentration and the response to hepatitis B vaccination.

Materials and method

The study involved 730 patients with recurrent respiratory infections. The concentration of 25-hydroxyvitamin D (25(OH)D), immunoglobulins G, A and M, anti-HBs was determined.

Results

The tests showed that 11% of patients presented IgG levels below the age related reference values. Children with reduced IgG concentration were also found to have significantly lower vitamin D concentrations in comparison to children with normal IgG. Vitamin D deficiency was observed in schoolchildren between 7 and 18 years of age. No correlation was found between 25(OH)D concentration and Hbs antibody levels.

Conclusions

An investigation of a large group of patients who have recurrent infection found patients with IgG deficiency to whom special proceeding have to be performed: 1. Significantly lower vitamin D concentration observed in the group of children with IgG deficiency implicated in long-lasting monitoring of vitamin D level require adding to the practice guidelines for Central Europe 2013. 2. Intervention treatment with suitable doses of vitamin D to clarified metabolism of vitamin D has to be plan for children with IgG deficiency and significant lower vitamin D concentration.  相似文献   
4.
Santosh Kumar 《Immunology》2018,154(3):383-393
Natural killer (NK) cells express an array of germ‐line encoded receptors that are capable of triggering cytotoxicity. NK cells tend to express many members of a given family of signalling molecules. The presence of many activating receptors and many members of a given family of signalling molecules can enable NK cells to detect different kinds of target cells, and to mount different kinds of responses. This contributes also to the robustness of NK cells responses; cytotoxic functions of NK cells often remain unaffected in the absence of selected signalling molecules. NK cells express many MHC‐I‐specific inhibitory receptors. Signals from MHC‐I‐specific inhibitory receptors tightly control NK cell cytotoxicity and, paradoxically, maintain NK cells in a state of proper responsiveness. This review provides a brief overview of the events that underlie NK cell activation, and how signals from inhibitory receptors intercept NK cell activation to prevent inappropriate triggering of cytotoxicity.  相似文献   
5.
Humoral immunodeficiency caused by mutations in the Wiskott-Aldrich syndrome protein (WASp) is associated with failure to respond to common pathogens and high frequency of autoimmunity. Here we addressed the question how deficiency in WASp and the homologous protein N-WASp skews the immune response towards autoreactivity. Mice devoid of WASp or both WASp and N-WASp in B cells formed germinal center to increased load of apoptotic cells as a source of autoantigens. However, the germinal centers showed abolished polarity and B cells retained longer and proliferated less in the germinal centers. While WASp-deficient mice had high titers of autoreactive IgG, B cells devoid of both WASp and N-WASp produced mainly IgM autoantibodies with broad reactivity to autoantigens. Moreover, B cells lacking both WASp and N-WASp induced somatic hypermutation at reduced frequency. Despite this, IgG1-expressing B cells devoid of WASp and N-WASp acquired a specific high affinity mutation, implying an increased BCR signaling threshold for selection in germinal centers. Our data provides evidence for that N-WASp expression alone drives WASp-deficient B cells towards autoimmunity.  相似文献   
6.
目的:探讨病毒性脑炎患儿脑脊液白蛋白比值(QAlb)、IgG和IgG指数变化与疾病严重程度的相关性。方法研究对象分病毒性脑炎组和对照组,病毒性脑炎组按临床特点分为轻症病毒性脑炎组和重症病毒性脑炎组,采用免疫散射比浊法测定血清和脑脊液的白蛋白、IgG,计算QAlb和IgG指数,判断病毒性脑炎患儿血脑屏障功能状态及免疫球蛋白鞘内合成情况与临床严重程度的关系。结果病毒性脑炎组的QAlb高于对照组;重症病毒性脑炎组的QAlb较轻症病毒性脑炎组和对照组增高,差异有统计学意义(P<0.05)。重症病毒性脑炎组脑脊液IgG、IgG指数比轻症病毒性脑炎组和对照组增高,差异有统计学意义(P<0.05)。结论重症病毒性脑炎组患儿的血脑屏障功能损害程度、鞘内IgG合成情况与临床病情严重程度相关。检测脑脊液和血清中白蛋白、IgG,计算QAlb和IgG指数能反映病毒性脑炎患儿血脑屏障功能状态及IgG鞘内合成情况,为判断病毒性脑炎临床病情的严重程度提供相关依据。  相似文献   
7.
目的探讨免疫分型、血清免疫球蛋白的定量检测在单株丙球蛋白血症诊断中的价值。方法收集118例单株丙球蛋白血症患者进行血清蛋白电泳(SPE)、免疫固定电泳(IF)、免疫球蛋白(Ig)定量及血清轻链(κ、λ)检测。针对免疫分型阳性、Ig定量阴性患者进行分析。结果免疫分型阳性、Ig定量阴性患者56例,其中游离轻链型6例(κ轻链型2例,λ轻链型4例),未分泌型1例;免疫分型阳性、Ig定量阳性的患者62例。结论 IF技术对单株丙球蛋白血症的诊断及分型具有重要意义,可以结合血清Ig及轻链的定量检测等其他实验室诊断。  相似文献   
8.
Immunosequencing is a platform technology that allows the enumeration, specification and quantification of each and every B‐ and/or T‐cell in any biologic sample of interest. Thus, it provides an assessment of the level and distribution of all the clonal lymphocytes in any sample, and allows “tracking” of a single clone or multiple clones of interest over time or from tissue to tissue within a given patient. It is based on bias‐controlled multiplex PCR and high‐throughput sequencing, and it is highly accurate, standardized, and sensitive. In this review, we provide evidence that immunosequencing is becoming an important analytic tool for the emerging field of immune‐oncology, and describe several applications of this approach, including the assessment of residual disease post therapy in lymphoid malignancies, the prediction of response to immunotherapeutics of solid tumors containing tumor infiltrating lymphocytes, the identification of clonal responses in vaccination, infectious disease, bone marrow reconstitution, and autoimmunity, and the exploration of whether there are population‐based stereotyped responses to certain exposures or interventions.  相似文献   
9.
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