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51.
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Mast cells (MCs) are responsible for the innate immune response. Rat MCs are more suitable than mouse MCs as models of specific parasite infection processes and ovalbumin-induced asthma. Rat peritoneum-derived MCs and RBL-2H3 cells (an MC cell line) are widely used in disease studies. However, the application of rat bone marrow-derived MCs (BMMCs) are poorly documented in terms of the methodology of rat BMMC isolation. Here, we describe a relatively rapid, efficient, and simple method for the cultivation of rat BMMCs. As compared to previous protocols, rat BMMCs produced with the proposed protocol exhibited advantages in differentiation, proliferation, lifespan, and functionality, which should prove useful for studies of mucosal MC diseases in specific rat models.  相似文献   
53.
主要分析ConA与不同的糖特异性结合时其活性位点构象变化的特征。模拟分析了ConA糖结合活性中心氨基酸残基结构特征,同时对相应残基原子可及性表面进行了计算和分析。结果表明:(1)ConA在和不同的糖结合时,存在不同的结合方式;(2)不管ConA和什么糖结合,主要的作用是由活性中心的Tyr12、Asn14、Asp208和Arg228提供的;(3)无论是结合单糖还是寡糖,活性中心总是与第一个糖环起主要的结合作用。  相似文献   
54.
The aim of this study was to evaluate the impact of zeolite powders on feasibility of rapid aerobic granulation in the column-type sequencing batch reactors. After 90 days' operation, aerobic granular sludge was formed in both reactors by altering influent chemical oxygen demand/nitrogen (COD/N) ratios. R1 with zeolite powders had better removal capabilities of COD and total nitrogen than R2, which was without zeolite powders. Mixed liquor volatile suspended solid concentrations of the two reactors were 7.36 and 5.45 g/L, while sludge volume index (SVI30) values were 34.9 and 47.9 mg/L, respectively. The mean diameters of aerobic granular sludge in the above two reactors were 2.5 and 1.5 mm, respectively. Both reactors achieved the largest simultaneous nitrification and denitrification (SND) efficiency at an influent COD/N ratio of 8; however, R1 exhibited more excellent SND efficiency than R2. The obtained results could provide a novel technique for rapid aerobic granulation and N removal simultaneously, especially when treating nitrogen-rich industrial wastewater.  相似文献   
55.
对2012 年全球上市新药的基本信息,包括通用名、商品名、结构式、CAS 号、研发公司、上市国家和主要适应证进行汇总,为新药研发工作者提供参考。  相似文献   
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伪叶甲科Lagriidae是鞘翅目的一个小科,全世界已知约2450种。过去有17位外国学者零星地记述了我国该科昆虫22属和124种6变种。1991年以来作者系统地研究了该科的分类、雄性外生殖器形态结构、系统发育和地理分布。本文报道莫伪叶甲属Merklia力和粗伪叶甲属Pachystira二个新属,及两斑莫伪叶甲Merkliabimaculata和凹翅粗伪叶甲Pachystiraimpressipennis二个新种。  相似文献   
58.
Jin H  Ma Y  Yan Z  Prabhakar BS  He B 《Journal of virology》2012,86(2):1059-1068
The γ134.5 protein of herpes simplex viruses (HSV) is essential for virulence. Accordingly, an HSV mutant lacking γ134.5 is attenuated in vivo. Despite its vaccine potential, the mechanism by which the γ134.5 null mutant triggers protective immunity is unknown. In this report we show that vaccination with the γ134.5 null mutant protects against lethal challenge from wild-type virus via IκB kinase in dendritic cells (DCs), which sense virus-associated molecular patterns. Unlike mock-treated DCs, DCs primed with the γ134.5 null mutant ex vivo mediate resistance to wild-type HSV after adoptive transfer into naïve mice. Furthermore, the γ134.5 null mutant activates IκB kinase, which facilitates p65/RelA phosphorylation and nuclear translocation, resulting in DC maturation. While unable to produce infectious virus in DCs, this mutant virus expresses early and late genes. In its abortive infection, the γ134.5 null mutant induces protective immunity more effectively in CD8+ DCs than in CD8 DCs. This is mirrored by a higher level of interleukin-6 (IL-6) and IL-12 secretion by CD8+ DCs than CD8 DCs. Remarkably, inhibition of p65/RelA phosphorylation or nuclear translocation in CD8+ DCs disrupts protective immunity. These results suggest that engagement of the γ134.5 null mutant with CD8+ DCs elicits innate immunity to activate NF-κB, which translates into protective immunity.  相似文献   
59.
Mechanical loading can induce or antagonize the extracellular matrix (ECM) synthesis, proliferation, migration, and inflammatory responses of annulus fibrosus cells (AFCs), depending on the loading mode and level. Caveolin-1 (Cav1), the core protein of caveolae, plays an important role in cellular mechanotransduction and inflammatory responses. In the present study, we presented that AFCs demonstrated different behaviors when subjected to cyclic tensile strain (CTS) for 24 h at a magnitude of 0%, 2%, 5% and 12%, respectively. It was found that 5% CTS had positive effects on cell proliferation, migration and anabolism, while 12% CTS had the opposite effects. Besides, cells exposed to interleukin-1β stimulus exhibited an increase expression in inflammatory genes, and the expression of these genes decreased after exposure to moderate mechanical loading with 5% CTS. In addition, 5% CTS decreased the level of Cav1 and integrin β1 and exhibited anti-inflammatory effects. Moreover, the expression of integrin β1 and p-p65 increased in AFCs transfected with Cav1 plasmids. In vivo results revealed that moderate mechanical stimulation could recover the water content and morphology of the discs. In conclusion, moderate mechanical stimulation restrained Cav1-mediated signaling pathway and exhibited anti-inflammatory effects on AFCs. Together with in vivo results, this study expounds the underlying molecular mechanisms on the effect of moderate mechanical stimulation on intervertebral discs (IVDs) and may provide a new therapeutic strategy for the treatment of IVD degeneration.  相似文献   
60.
本文旨在探究黄芩川贝母不同比例配伍后对黄芩中主要化学成分含量影响及等比配伍后抗肺炎作用.将黄芩川贝母按3∶0、3∶1、3∶2、3∶3、2∶3、1∶3、0∶3比例配伍后,水提取,高效液相色谱法测定黄芩苷、汉黄芩苷、黄芩素、汉黄芩素含量.选择健康ICR小鼠36只,随机分为6组,分别为空白组、LPS组、阳性药组、黄芩组、川贝...  相似文献   
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