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1.
过度运动、适度运动与免疫   总被引:2,自引:0,他引:2  
随着免疫学的发展,运动与免疫机能的关系越来越受到人们的关注。不同的运动形式和运动强度对免疫机能的影响也不同,适宜的运动强度和运动量,能提高机体的免疫机能,而过度运动,则降低机体的免疫机能,使运动能力下降。  相似文献   

2.
SAP is required for generating long-term humoral immunity   总被引:21,自引:0,他引:21  
Crotty S  Kersh EN  Cannons J  Schwartzberg PL  Ahmed R 《Nature》2003,421(6920):282-287
Long-lived plasma cells and memory B cells are the primary cellular components of long-term humoral immunity and as such are vitally important for the protection afforded by most vaccines. The SAP gene has been identified as the genetic locus responsible for X-linked lymphoproliferative disease, a fatal immunodeficiency. Mutations in SAP have also been identified in some cases of severe common variable immunodeficiency disease. The underlying cellular basis of this genetic disorder remains unclear. We have used a SAP knockout mouse model system to explore the role of SAP in immune responses. Here we report that mice lacking expression of SAP generate strong acute IgG antibody responses after viral infection, but show a near complete absence of virus-specific long-lived plasma cells and memory B cells, despite the presence of virus-specific memory CD4+ T cells. Adoptive transfer experiments show that SAP-deficient B cells are normal and the defect is in CD4+ T cells. Thus, SAP has a crucial role in CD4+ T-cell function: it is essential for late B-cell help and the development of long-term humoral immunity but is not required for early B-cell help and class switching.  相似文献   

3.
了解保水剂和水泥对人工土壤钾素的影响有助于提高土壤钾素有效性,有利于边坡的植被恢复.本文以保水剂和水泥为基质原材料,选用L9(32)正交表进行试验,研究不同保水剂和水泥含量对土壤钾素形态的影响以及作用机制.结果表明,保水剂和水泥显著增加土壤速效钾、非交换性钾、水溶性钾、特殊吸附钾和非特殊吸附钾含量,而土壤全钾和矿物钾含量均有不同程度地减少.同时,0.30%保水剂和4%水泥能显著提高黑麦草的发芽率,但是过量的保水剂和水泥则明显降低了种子的发芽率.相关性分析表明,土壤pH与土壤有机质是影响土壤钾素有效性的重要因子.保水剂和水泥的施用可提高土壤中速效钾和非交换性钾的含量,促进土壤钾素组分之间的转化,提升土壤钾素有效性.  相似文献   

4.
为从基因转录水平了解大鼠肝再生中Toll样受体信号通路调节库普弗细胞免疫反应的途径和方式,首先建立大鼠2/3肝切除(partial hepatectomy,PH)模型,从中分离库普弗细胞进行基因微阵列分析.发现Toll样受体信号通路的23个基因及其调节免疫反应的62个基因与大鼠肝再生相关.基因协同作用(Ep(t)值)和同类提取法分析表明,大鼠肝再生进展阶段,Toll样受体信号通路通过TLR/NF-κB,TLR/MAPK,TLR/IRF等3条途径和TLR4,MAL,UNC93B1,AP1S2,IRF1等5个关键基因抑制库普弗细胞免疫反应.  相似文献   

5.
圆弧菌醇和圆弧菌素的分离纯化及结构解析   总被引:1,自引:0,他引:1  
肿瘤坏死因子α(TNF-α)是激活的巨噬细胞分泌的一种多功能因子,其过量表达可以引起类风湿性关节炎和其他自身免疫性疾病.因此,寻找开发其小分子抑制剂具有重要意义.在对一株分离自厦门海沧红树林土壤青霉属(Peni-cilliumsp.)真菌的次级代谢产物进行分离纯化以获得TNF-α抑制剂的研究中,通过中压反相硅胶柱层析(RP-18)、常压凝胶柱层析(Sephadex LH-20)、硅胶柱层析(Si-Gel)等柱层析技术对两种产量较高的化合物进行了分离纯化.通过对两个化合物的一维(1D-)、二维(2D-)核磁共振(NMR)和质谱(MS)数据的深入解析,确定两个化合物为生物碱圆弧菌醇和圆弧菌素,两者的产率分别达7.0和3.9mg/L,并通过X射线单晶衍射确定了圆弧菌醇手性碳的绝对构型.圆弧菌醇和圆弧菌素是生物合成TNF-α诱导的人类HIV病毒复制强抑制剂纯绿青霉素过程的中间产物,但是在拮抗过量TNF-α的实验中并没有表现出明显的活性.该研究为开发利用这两种生物碱及通过生物转化合成纯绿青霉素,及加速新的潜在免疫抑制剂的研究提供基础.  相似文献   

6.
白细胞介素21(IL-21)是一种新近发现的、具有免疫调节作用的细胞因子,可通过多途径影响CD4+T细胞的应答,增强CD8+T细胞介导的抗HIV/SIV作用,具有潜在的抗HIV/SIV的临床应用前景。血清IL-21水平测定有望作为确定HIV感染者AIDS病程以及HIV感染者抗病毒治疗反应的重要免疫学参数。近年来关于IL-21免疫调节HIV/SIV感染者T淋巴细胞的研究日益增多,并取得了一些成果。  相似文献   

7.
The 1918 influenza pandemic was unusually severe, resulting in about 50 million deaths worldwide. The 1918 virus is also highly pathogenic in mice, and studies have identified a multigenic origin of this virulent phenotype in mice. However, these initial characterizations of the 1918 virus did not address the question of its pathogenic potential in primates. Here we demonstrate that the 1918 virus caused a highly pathogenic respiratory infection in a cynomolgus macaque model that culminated in acute respiratory distress and a fatal outcome. Furthermore, infected animals mounted an immune response, characterized by dysregulation of the antiviral response, that was insufficient for protection, indicating that atypical host innate immune responses may contribute to lethality. The ability of influenza viruses to modulate host immune responses, such as that demonstrated for the avian H5N1 influenza viruses, may be a feature shared by the virulent influenza viruses.  相似文献   

8.
H Schorle  T Holtschke  T Hünig  A Schimpl  I Horak 《Nature》1991,352(6336):621-624
Interleukin-2 (IL-2) is a lymphocytotropic hormone which is thought to have a key role in the immune response of mammalian cells. It is produced by a subpopulation of activated T-lymphocytes and acts in vitro as the principal auto- and paracrine T-cell growth factor (for reviews see refs 1-3). IL-2 is, however, not the sole T-cell growth factor, nor does it act exclusively on T cells, also promoting growth of NK cells and differentiation of B cells. A role for IL-2 in T-cell development has been postulated but remains controversial. Here we test the requirement for IL-2 in vivo using IL-2-deficient mice generated by targeted recombination. We find that mice homozygous for the IL-2 gene mutation are normal with regard to thymocyte and peripheral T-cell subset composition, but that a dysregulation of the immune system is manifested by reduced polyclonal in vitro T-cell responses and by dramatic changes in the isotype levels of serum immunoglobulins.  相似文献   

9.
The homeostasis of the immune response requires tight regulation of the proliferation and apoptosis of activated lymphocytes. In humans, defects in immune homeostasis result in lymphoproliferation disorders including autoimmunity, haemophagocytic lymphohystiocytosis and lymphomas. The X-linked lymphoproliferative syndrome (XLP) is a rare, inherited immunodeficiency that is characterized by lymphohystiocytosis, hypogammaglobulinaemia and lymphomas, and that usually develops in response to infection with Epstein-Barr virus (EBV). Mutations in the signalling lymphocyte activation molecule (SLAM)-associated protein SAP, a signalling adaptor molecule, underlie 60% of cases of familial XLP. Here, we identify mutations in the gene that encodes the X-linked inhibitor-of-apoptosis XIAP (also termed BIRC4) in patients with XLP from three families without mutations in SAP. These mutations lead to defective expression of XIAP. We show that apoptosis of lymphocytes from XIAP-deficient patients is enhanced in response to various stimuli including the T-cell antigen receptor (TCR)-CD3 complex, the death receptor CD95 (also termed Fas or Apo-1) and the TNF-associated apoptosis-inducing ligand receptor (TRAIL-R). We also found that XIAP-deficient patients, like SAP-deficient patients, have low numbers of natural killer T-lymphocytes (NKT cells), indicating that XIAP is required for the survival and/or differentiation of NKT cells. The observation that XIAP-deficiency and SAP-deficiency are both associated with a defect in NKT cells strengthens the hypothesis that NKT cells have a key role in the immune response to EBV. Furthermore, by identifying an XLP immunodeficiency that is caused by mutations in XIAP, we show that XIAP is a potent regulator of lymphocyte homeostasis in vivo.  相似文献   

10.
 癌症严重威胁人类健康,是当前最引人关注的疾病领域。肿瘤免疫治疗在癌症治疗中具有独特优势,受到越来越多研究机构和制药企业的青睐,近年来呈现蓬勃发展的趋势。由于免疫系统的复杂性,肿瘤免疫治疗涵盖了多种作用机制和药物形式,发展情况各不相同。本文通过调研大量文献和数据库信息,对国内外处在临床试验阶段和已经上市的肿瘤免疫药物进行了梳理,对其发展阶段、作用机制、研发机构等情况进行分析,旨在阐述肿瘤免疫药物开发的总体趋势和方向,为抗肿瘤药物研发提供借鉴。  相似文献   

11.
研究了采用分步酸浸工艺处理高铁铝土矿新工艺中,低温酸浸过程主要工艺条件对矿物中铁、铝、钪等有价元素走向的影响,以及酸浸液后续萃取分离过程特点。结果表明:低温酸浸过程可实现矿物中的铁、铝分离,在浸出温度100℃、浸出时间60min、液固比20∶1、搅拌速率500rpm、粒度-0.055mm、硫酸浓度20%的低温酸浸条件下,矿物中的铁浸出率可达95%以上,钪的浸出率可达50%以上,铁、铝酸浸分离系数可达到80左右,浸出液可通过多级循环后萃取的方式提取其中的钪,在适宜的萃取条件下,钪的提取效率可达99%以上。  相似文献   

12.
Shankaran V  Ikeda H  Bruce AT  White JM  Swanson PE  Old LJ  Schreiber RD 《Nature》2001,410(6832):1107-1111
Lymphocytes were originally thought to form the basis of a 'cancer immunosurveillance' process that protects immunocompetent hosts against primary tumour development, but this idea was largely abandoned when no differences in primary tumour development were found between athymic nude mice and syngeneic wild-type mice. However, subsequent observations that nude mice do not completely lack functional T cells and that two components of the immune system-IFNgamma and perforin-help to prevent tumour formation in mice have led to renewed interest in a tumour-suppressor role for the immune response. Here we show that lymphocytes and IFNgamma collaborate to protect against development of carcinogen-induced sarcomas and spontaneous epithelial carcinomas and also to select for tumour cells with reduced immunogenicity. The immune response thus functions as an effective extrinsic tumour-suppressor system. However, this process also leads to the immunoselection of tumour cells that are more capable of surviving in an immunocompetent host, which explains the apparent paradox of tumour formation in immunologically intact individuals.  相似文献   

13.
通过BP世界能源统计(BP Statistical Review of World Energy June 2010)数据,对全球常规能源状况及常规能源发展带动的新能源发展做出分析和比较。结果表明:一是全球常规能源探明储量在增加,可增加相比消耗的增长是缓慢的;二是常规能源输运是全球重要而繁重的输运;三是全球能源处于从常规能源到新能源过渡的转型期,新能源发展迅猛,目前虽然不能和常规能源相比,但未来将超过常规能源。世界能源处于一场新的革命阶段,关注世界能源状况和发展,建构中国能源与世界能源的种种关系极为重要,国家应充分认清世界能源的客观现实,为这一场革命做好准备。  相似文献   

14.
肿瘤浸润免疫细胞通过发挥促肿瘤和抗肿瘤的作用,可以深刻地影响肿瘤的进展以及抗癌治疗的成功.因此,对于肿瘤浸润免疫细胞的量化有望揭示免疫系统在人类癌症中的多方面作用及其参与肿瘤逃逸机制和对治疗的反应.解卷积的目的就是试图在复杂组织里存在的免疫细胞中寻找新的免疫疗法,其核心思想是利用算法和免疫细胞的表达特征,从细胞混合物的表达数据中量化免疫细胞比例信息,以准确刻画肿瘤样本测序数据的免疫浸润情况.为此,提出了一个新的基于逐步回归策略的解卷积算法模型,并使用真实的肿瘤样本微阵列数据和RNA-Seq测序数据来测试该算法的准确性.与CIBERSORT和dtangle相比较,具有良好的解卷积性能.  相似文献   

15.
The immunopathogenesis of sepsis   总被引:110,自引:0,他引:110  
Cohen J 《Nature》2002,420(6917):885-891
Sepsis is a condition that results from a harmful or damaging host response to infection. Many of the components of the innate immune response that are normally concerned with host defences against infection can, under some circumstances, cause cell and tissue damage and hence multiple organ failure, the clinical hallmark of sepsis. Because of the high mortality of sepsis in the face of standard treatment, many efforts have been made to improve understanding of the dysregulation of the host response in sepsis. As a result, much has been learnt of the basic principles governing bacterial-host interactions, and new opportunities for therapeutic intervention have been revealed.  相似文献   

16.
Immunotherapy is an ascendant approach in cancer treatment. It shows more pronounced effects on killing cancer cells in a specific manner in particular against metastasis more than traditional techniques, such as chemotherapy or surgery. However, tumor immunosuppression limits the response of the immune system to cancer development. In this study, we developed a lipid-based nanocarrier doubly loaded with imiquimod (R837), a toll-like receptor 7 agonist, and caffeine, an adenosine receptor antagonist. This R837/caffeine loaded nanocarrier served as a nano-immunomodulator (RC-nIM) for combination treatment with radiotherapy (RT) against orthotopic breast cancer. RT-induced immunogenic cell death facilitated the production of tumor antigen and elicited the immune response in corporation with R837-medaited activation of antigen-presenting cells (APCs) while RC-nIMs being adopted. Additionally, caffeine, an adenosine analog, can successfully compete with adenosine in the tumor. The tumor-bearing mice that received RT together with RC-nIMs experienced the best antitumor effects and exhibited higher levels of T cells and APCs within the tumor; the growth of secondary tumors was also limited. This work serves as a proof-of-concept study for the development of a new immunotherapy strategy against cancer.  相似文献   

17.
树突状细胞(Dendritic cells,DCs)是最有效的抗原呈递细胞.DCs能够摄取外来物质,包括结核分枝杆菌(Mycobacterium tuberculosis,MTB),并将其呈递给效应性淋巴细胞,激发宿主对抗病原微生物感染的免疫反应.因此,树突状细胞与结核分枝杆菌的相互作用在感染初期机体发动免疫应答中十分重要.研究树突状细胞和结核分枝杆菌间的相互作用,有利于从根本上了解细菌-宿主作用机理,为阐明结核分枝杆菌逃避免疫的机制提供依据.  相似文献   

18.
不稳定型心绞痛患者血浆IL-10、IL-19和IL-20水平的变化   总被引:1,自引:0,他引:1  
目的:探讨血浆白细胞介素(IL)-10家族成员IL-10、IL-19和IL-20水平与不稳定型心绞痛的关系.方法:冠心病患者52例,其中36例不稳定型心绞痛患者(UAP组),16例稳定型心绞痛患者(SAP组).同期江汉大学附属医院健康体检者20例作为对照组.采用ELISA法检测上述患者血浆中IL-10、IL-19及IL...  相似文献   

19.
With the rise of various cloud services, the problem of redundant data is more prominent in the cloud storage systems. How to assign a set of documents to a distributed file system, which can not only reduce storage space, but also ensure the access efficiency as much as possible, is an urgent problem which needs to be solved.Space-efficiency mainly uses data de-duplication technologies, while access-efficiency requires gathering the files with high similarity on a server. Based on the study of other data de-duplication technologies, especially the Similarity-Aware Partitioning(SAP) algorithm, this paper proposes the Frequency and Similarity-Aware Partitioning(FSAP) algorithm for cloud storage. The FSAP algorithm is a more reasonable data partitioning algorithm than the SAP algorithm. Meanwhile, this paper proposes the Space-Time Utility Maximization Model(STUMM), which is useful in balancing the relationship between space-efficiency and access-efficiency. Finally, this paper uses 100 web files downloaded from CNN for testing, and the results show that, relative to using the algorithms associated with the SAP algorithm(including the SAP-Space-Delta algorithm and the SAP-Space-Dedup algorithm), the FSAP algorithm based on STUMM reaches higher compression ratio and a more balanced distribution of data blocks.  相似文献   

20.
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