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191.
蜱体内含有多种生物学功能分子物质,组胺结合蛋白(HBP)是其中之一。对自HBP发现以来,关于其生物学特性及其在蜱体内分布等方面的相关研究进展进行了总结,以期为全面深入地认识HBP提供参考。  相似文献   
192.
Toll-like receptors (TLRs) are a group of highly conserved molecules which initiate the innate immune response to pathogens by recognizing structural motifs of microbes. Understanding the changes in chicken Toll-like receptors (ChTLRs) and signal adaptors expression that occur with Eimeria tenella infection will help to elucidate the molecular basis of immune control of coccidiosis caused by Eimeria. The present study detected the dynamic changes in the expression of ChTLRs and associated signal adaptors in the spleen and cecum ofE. tenella-infected chickens during the early stage of infection. The results showed that the expression peak for ChTLRs, MyD88 and TRIF occurred at 12 h post-infection (hpi), ChTLR3, ChTLRI 5 and MyD88 mRNA expression in the spleen ofE. tenella infected chickens were significantly higher (P〈0.05) than that of negative control chickens, and there were similar tendencies of these molecules expression in the cecum and spleen of E. tenella-infected chickens. The expression of MyD88 was upregnlated at four time points in the cecum of E. tenella-infected chickens. The results of this study indicate that ChTLR3, ChTLR15 and MyD88 play a role in young chickens infected with E. tenella.  相似文献   
193.
This paper overviews some recent developments in mammalian corneal immunobiology, and discusses how these may act as pointers towards understanding the immunology underlying some common corneal diseases in the horse, including infectious ulceration and presumptively immune-mediated non-ulcerative disease. Specifically, three aspects of corneal immunobiology are examined: the role of Toll-like receptors in surface immunity and in the etiogenesis of microbial ulceration, the relationship between conjunctiva associated lymphoid tissue (CALT) and immunoprotection of the corneal surface, and the mechanisms determining corneal immune privilege (IP) and how down regulation of IP may be an important factor in the genesis of corneal immunoinflammatory disease.  相似文献   
194.
AIM:To establish the method for detecting the immunophenotype of immunosuppressive receptor programmed cell death protein 1 (PD-1) in T-cell receptor (TCR) Vβ repertoire of CD3+, CD4+ and CD8+ T-cell subsets, therefore to evaluate the distribution of PD-1 in T-cell repertoire from human peripheral blood (PB). METHODS:The PB samples from 10 cases of healthy individuals (HI) were collected. Using multi-colored fluorescence flow cytometry, the distribution frequency of PD-1 in TCR Vβ repertoire was detected with a wide panel of anti-CD45, anti-CD3, anti-CD4, anti-CD8, anti-PD-1 and 24 anti-TCR Vβ repertoire (IOTest® Beta Mark TCR Vβ Repertoire Kit, containing 8 tubes which labeled A~H, each tube is a composite antibody of FITC and PE coupling, each cocktail contains antibodies direc-ted to 3 different Vβ subfamilies) monoclonal antibodies. RESULTS:The total number of the 24 TCR Vβ repertoire detected in CD3+, CD3+CD4+ and CD3+CD8+ T cells from 10 cases of HI was consistent with the Quick Reference Card data provided by the kit. The preliminary results showed that the frequency of Vβ usage in CD3+, CD4+ and CD8+ T cells was different. High usage of Vβ2, Vβ3, Vβ8, Vβ9, Vβ5.1, Vβ13.1 and Vβ13.2 was found in CD3+ T cells, while high usage of Vβ2, Vβ3, Vβ8, Vβ5.1, Vβ9 and Vβ13.1 in CD3+CD4+ T cells, and high usage of Vβ1, Vβ2, Vβ3, Vβ9, Vβ13.1 and Vβ13.2 in CD3+CD8+ T cells were also observed. Further analysis showed that the expression of PD-1 was detected in all 24 TCR Vβ subfamilies of CD3+, CD3+CD4+ and CD3+CD8+ T cells. The higher frequency of PD-1+ T cells was CD4+Vβ5.2+ T cells, whereas the higher frequency of PD1+ T cells in CD8+Vβ11+ and CD8+Vβ13.6+ T cells was detected. CONCLUSION:The method for detection of the immunosuppressive receptor PD-1 in TCR Vβ repertoire of T-cell subsets is successfully established, which provides a new method for further analysis of immunosuppressive characteristics of TCR Vβ repertoire in the patients with leukemia.  相似文献   
195.
用免疫组化SP法检测了去势及去势后补充雄激素大鼠脊髓灰质缘核中雄激素受体(Androgen receptors,AR)蛋白的表达情况,以探讨雄激素对缘核的作用。结果表明,睾丸摘除组大鼠缘核内AR蛋白的表达和睾丸摘除并用睾酮替代组大鼠缘核内AR蛋白的表达接近。说明去睾丸大鼠阻断其内源性雄激素后,对缘核AR蛋白表达影响甚小,而补充外源性雄激素对此影响不大。  相似文献   
196.
菠萝对乙烯利诱花的敏感性差异研究   总被引:2,自引:0,他引:2  
为了解造成2种不同类型菠萝品种对乙烯敏感性差异的发生环节,进一步揭示乙烯促进菠萝成花的分子机制,本研究以乙烯敏感型‘巴厘’菠萝品种和乙烯钝感型‘台农16’菠萝品种为试材,对乙烯催花过程中成花基因及乙烯信号转导途径中乙烯受体、信号转导和核内调控等过程涉及基因的表达特征进行了分析。结果表明:AcERS1a、AcETR2a、AcETR2b、AcCTR1、AcENI2和AcERFs等基因在2种成花类型中的差异可能是导致2个品种对乙烯信号感知敏感度不同的重要原因;AcERS1a、AcERS1b、AcETR2a和AcETR2b等乙烯受体可能参与乙烯诱导菠萝成花信号的感知,然后通过AcCTR1下调和AcENI2上调将信号转导至核内调控基因(AcEIN3和AcERFs),从而启动菠萝成花关键基因AcFT和花器官形态建成重要基因AcAP1的表达,引起菠萝成花的生物学效应,这将为进一步阐明乙烯诱导菠萝成花的分子机制提供参考,也为利用基因工程手段开展菠萝新品种选育奠定了基础。  相似文献   
197.
AIM: To investigate the effects of sodium hydrosulfide (NaHS), a donor of hydrogen sulfide (H2S), on the membrane permeability, intracellular Ca2+ concentration ([Ca2+]i) and the release of IL-1β induced by adenosine triphosphate (ATP) in rat microglia, and to explore the effect of H2S on ATP-P2X purinergic signaling pathway and the molecular mechanism of its neuroprotective effect. METHODS: Rat microglia in logarithmic growth phase were used in the study. The[Ca2+]i was detected by Fura-2/AM staining. Fluorescent dye YO-PRO-1 was used to observe the membrane permeability. Interleukin-1β (IL-1β) was measured by rat IL-1β ELISA kits. RESULTS: The YO-PRO-1 fluorescence intensity was obviously elevated by ATP induction in a dose-dependent manner in the rat microglia, but this effect was counteracted by NaHS pretreatment (P<0.05).[Ca2+]i rapidly increased and then decreased slowly, forming a stable platform for a long time when rat microglia were treated with ATP. Ca2+ spike activity induced by ATP had no change, but the platform disappeared (P<0.05) after NaHS pretreatment. The ATP and LPS together facilitated the release of IL-1β, but the phenomenon was inhibited by NaHS (P<0.05). CONCLUSION: Hydrogen sulfide may decrease the membrane permeability, calcium inflow and IL-1β release in rat microglia activated by high dose of ATP. The cytoprotection of hydrogen sulfide may be mediated by purinergic signaling pathway.  相似文献   
198.
For a small library of natural products from marine sponges and ascidians, in silico docking to the Lymnaea stagnalis acetylcholine-binding protein (AChBP), a model for the ligand-binding domains of nicotinic acetylcholine receptors (nAChRs), was carried out and the possibility of complex formation was revealed. It was further experimentally confirmed via competition with radioiodinated α-bungarotoxin ([125I]-αBgt) for binding to AChBP of the majority of analyzed compounds. Alkaloids pibocin, varacin and makaluvamines С and G had relatively high affinities (Ki 0.5–1.3 μM). With the muscle-type nAChR from Torpedo californica ray and human neuronal α7 nAChR, heterologously expressed in the GH4C1 cell line, no competition with [125I]-αBgt was detected in four compounds, while the rest showed an inhibition. Makaluvamines (Ki ~ 1.5 μM) were the most active compounds, but only makaluvamine G and crambescidine 359 revealed a weak selectivity towards muscle-type nAChR. Rhizochalin, aglycone of rhizochalin, pibocin, makaluvamine G, monanchocidin, crambescidine 359 and aaptamine showed inhibitory activities in electrophysiology experiments on the mouse muscle and human α7 nAChRs, expressed in Xenopus laevis oocytes. Thus, our results confirm the utility of the modeling studies on AChBPs in a search for natural compounds with cholinergic activity and demonstrate the presence of the latter in the analyzed marine biological sources.  相似文献   
199.
为研究大菱鲆过氧化物酶体增殖物激活受体家族(PPARs)的组织分布和高温胁迫下PPARs在肾脏中的表达情况。实验采用荧光定量PCR(qPCR)技术检测PPARs基因3种亚型在大菱鲆不同组织中的表达情况以及高温胁迫下大菱鲆肾脏中PPARs的表达情况。qPCR结果显示,大菱鲆PPARs 3种亚型的组织分布存在显著差异。PPARα1和PPARα2在心脏中的表达量显著高于其他组织;PPARβ在大菱鲆的各个组织中普遍表达;PPARγ在大菱鲆的鳃中出现了显著性的高表达。大菱鲆肾脏中PPARs的mRNA水平随着温度升高呈现出不同的响应模式。PPARα随温度升高表达水平先显著降低,后有所升高;PPARβ的表达量在14、20、23和25℃时差异不显著,当温度升高至大菱鲆的致死温度28℃时,表达量出现了显著性的升高;PPARγ在14℃时表达水平很低,但随着温度的升高不断增加。研究表明,大菱鲆中存在PPARα、PPARβ和PPARγ3种亚型,而且三者可能以组织特异性的方式参与脂质代谢的调节,首次指出PPARs 3种亚型在温度胁迫中的表达变化,对PPARs的研究将推动鱼类脂代谢研究,揭示鱼类PPARs在脂质代...  相似文献   
200.
二磷酸组织胺对奶牛血浆内毒素含量的影响   总被引:7,自引:2,他引:5  
本文采用动物实验方法,给8头健康奶牛颈部皮下注射二磷酸组织胺,剂量为150μg/kg体重。于给药前、给药后2小时和12小时分别采取血样,采用试验法测定血浆内毒素含量,结果表明,给药前血浆内毒素含量平均为0.39Eu/ml,给药后2小时和12小时分别为0.71Eu/ml和0.83Eu/m;。与给药前相比,给药后12小时,血浆内毒素含量极显著升高(P〈0.005)。文章首次报道了组织胺对血浆内毒含量的  相似文献   
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