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排序方式: 共有2311条查询结果,搜索用时 31 毫秒
1.
Valentina Tedeschi Giorgia Paldino Fabiana Paladini Benedetta Mattorre Loretta Tuosto Rosa Sorrentino Maria Teresa Fiorillo 《International journal of molecular sciences》2020,21(24)
The strong association with the Major Histocompatibility Complex (MHC) class I genes represents a shared trait for a group of autoimmune/autoinflammatory disorders having in common immunopathogenetic basis as well as clinical features. Accordingly, the main risk factors for Ankylosing Spondylitis (AS), prototype of the Spondyloarthropathies (SpA), the Behçet’s disease (BD), the Psoriasis (Ps) and the Birdshot Chorioretinopathy (BSCR) are HLA-B*27, HLA-B*51, HLA-C*06:02 and HLA-A*29:02, respectively. Despite the strength of the association, the HLA pathogenetic role in these diseases is far from being thoroughly understood. Furthermore, Genome-Wide Association Studies (GWAS) have highlighted other important susceptibility factors such as Endoplasmic Reticulum Aminopeptidase (ERAP) 1 and, less frequently, ERAP2 that refine the peptidome presented by HLA class I molecules to CD8+ T cells. Mass spectrometry analysis provided considerable knowledge of HLA-B*27, HLA-B*51, HLA-C*06:02 and HLA-A*29:02 immunopeptidome. However, the combined effect of several ERAP1 and ERAP2 allelic variants could generate an altered pool of peptides accounting for the “mis-immunopeptidome” that ranges from suboptimal to pathogenetic/harmful peptides able to induce non-canonical or autoreactive CD8+ T responses, activation of NK cells and/or garbling the classical functions of the HLA class I molecules. This review will focus on this class of epitopes as possible elicitors of atypical/harmful immune responses which can contribute to the pathogenesis of chronic inflammatory diseases. 相似文献
2.
The colour of the background on which products are presented may affect their perceived attractiveness. In order to find out on which type of background various fresh food products look most attractive, we presented five different vegetables (tomato, carrot, yellow bell pepper, eggplant, mushroom) on five different backgrounds with neutral grey colours varying in degree of blackness: 5, 30, 50, 65, and 90%. Forty-six participants provided colour matches for the vegetables and evaluated them on 10 attributes.Overall, the blackness of the backgrounds had little or no effect on the perceived colour of the vegetable. Only for carrots we found a small but significant difference, mainly between the 5% and 90% blackness backgrounds. On the darkest background, the carrot would be perceived as a bit lighter, more saturated, and more yellow rather than red, compared to the lightest background.Differences in perceived attractiveness on the grey backgrounds varied between 0.3 and 1.0 units on a 9-point scale. Attractiveness and expensiveness ratings for most vegetables were highest on the 90% blackness background. In comparison to our previous study where we presented vegetables on hued backgrounds, differences between mean attractiveness ratings were smaller. Because mean attractiveness ratings in the current study were higher, we expect that grey backgrounds are more likely to present vegetable assortments with a variety of hues in an attractive way than hued backgrounds. 相似文献
3.
Duplicated code detection has been an active research field for several decades. Although many algorithms have been proposed, only a few researches have focussed on the comprehensive presentation of the detected clones. During the evaluation of clone detectors developed by the authors, it was observed that the results of the clone detectors were hard to comprehend. Therefore, in this paper a broadly suitable grouping method with which clone pairs can be easily grouped together to provide a more compact result is presented. The grouping algorithm is examined and a more precise revised algorithm is proposed to present all of the candidates to the user. 相似文献
4.
以东安513型汽油发动机整机为例,基于ANSYS有限元分析软件对其进行流体场、瞬态温度场以及瞬态结构场的多物理场双向耦合研究,实现了对发动机实际工况下的有限元分析。研究了发动机整机在实际工况下的受力以及密封情况,并对现有发动机组合结构存在的密封缺陷进行优化调整。文中详细阐述了在分析过程中涉及到的关键技术和要点,并最终获得了发动机整机实际工作状态下的多个结果云图。根据分析结果云图可以发现,发动机在热载荷、螺栓预紧力以及爆破压力的共同影响下,会使整机发生一定的形变,这种变形会影响其工作状况下的密封性能。通过对分析结果的研究,最终选择调整螺栓预紧力的大小和分布来提高发动机密封性能。 相似文献
5.
磁珠分选原理与分选试验研究 总被引:2,自引:0,他引:2
在对磁珠的磁选原理和磁选动力学分析的基础上,得出了磁珠在磁场中所受磁力和从磁选机中分离出磁珠所需磁力的计算公式,给出了不同分选次数和分选工艺的分选效果,得出了采用弱磁场磁选机能够有效回收粉煤灰中磁珠的重要结论。 相似文献
6.
根据永平铜矿实际爆破情况,运用爆轰理论,对露天矿垂直与倾斜两种中深孔的爆破特征进行了分析.分析从底盘抵抗线、孔网参数、大块与粮底、钻孔效率与作业成本和爆破地震效应五个方面入手,阐述了两种不同类型钻孔的不同爆破作用机制及其爆玻效果,肯定了倾斜孔在露天台阶爆破中所具有的独特优越性. 相似文献
7.
针对井筒不同段高的水文地质条件及井壁质量情况 ,采取不同的注浆工艺 ,对井筒孔裂隙水进行综合治理 ,取得了较好效果 相似文献
8.
影响中国大气降水稳定同位素组成的主要因素分析 总被引:11,自引:0,他引:11
本文根据中国大气降水同位素监测网近几年来(1985~1993年)20多个台站的监测结果,以相关分析的形式,探讨了各种气象要素、地理环境因素,对形成我国大气降水稳定同位素组成的影响机理和结果。给出了中国大气降水稳定同位素月雨量加权平均值区域分布图。 相似文献
9.
介绍了LLL1200×650B型煤泥离心机的工作原理,技术参数及主要技术特点,对其使用情况进行了分析,指出该离心机具有产品水分低,设备性能稳定,工作可靠等特点。 相似文献
10.
为了满足市场对商品煤煤质的要求,正阳煤矿选煤厂为提高商品煤的发热量、降低灰分,经多次外出考察、论证,选用了复合式干法选煤机。安装投产后,商品煤灰分降低8%~14%,发热量平均升高669.89 KJ/t。效果显著,不到半年即可收回全部投资。 相似文献