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81.
82.
Latency associated peptide (LAP) is a protein expressed on the membrane of some regulatory T cells (Treg). LAP+ Treg have a greater immunomodulatory effect than that of their negative counterparts. In this study, we presented the data on the proportion of LAP+ Treg out of CD4+ cells in mice with viral myocarditis, which we believed was more sensitive and specific than that of the ratio of total Treg in CD4+ cells. Comparing with the previously recognized total Treg, LAP+ Treg was a better biomarker on myocardial inflammation.  相似文献   
83.
A deficiency of complement factor H may lead to excessive consumption of C3 and an increase in C3b deposition, which are important pathological characteristics of lupus nephritis. Complement factor H-related proteins (CFHRs), comprising CFHR1 to CFHR5 (CFHR1–5), are members of the wider factor H/CFHR family. Their role in lupus nephritis remains unclear. In this study, we compared circulating levels of CFHR1–5 in 152 patients diagnosed with lupus nephritis and 20 unrelated healthy individuals to explore the relationship between the expression of CFHR1–5 and development of the disease. We found that plasma levels of CFHR3 and CFHR5 were higher in patients with lupus nephritis than in healthy individuals; also, CFHR3 and CFHR5 concentrations increased with increasing systemic lupus erythematosus disease activity index (SLEDAI) values (P < 0.05). Pearson's and Spearman's correlation test results confirmed that plasma CFHR3 and CFHR5 levels in lupus nephritis patients were positively correlated with proteinuria and levels of creatinine (Cr) and anti-dsDNA (correlation coefficients = 0.491–0.717, P < 0.05), while they were negatively correlated with plasma C3 levels and eGFR [correlation coefficients = –(0.706–0.788), P < 0.05]. Receiver operating characteristic (ROC) curve analysis results confirmed that plasma CFHR3 and CFHR5 levels were predictive of SLEDAI values and disease end points (area under the curve = 0.664–0.884, P < 0.05), with patients with both high CFHR3 and high CFHR5 exhibiting the shortest progression-free survival. Thus, both CFHR3 and CFHR5 are of prognostic value in lupus nephritis status.  相似文献   
84.
The Cluster of differentiation 226(CD226)/T cell immunoglobulin and immune receptor tyrosine-based inhibitory motif domain (TIGIT) axis plays an important role in the balance of the immune response. A previous study showed that CD226 is involved in CD4+ T cell differentiation and that blocking CD226 may attenuate experimental autoimmune encephalomyelitis (EAE) development. However, the molecular mechanisms underlying this process remain incompletely understood. In this study, it was found that Cd226−/− mice were less susceptible to EAE and that there was less T helper 17(Th17) cell infiltration with higher levels of regulatory cells (Tregs) infiltration in the Cd226−/− EAE mouse central nervous system (CNS) compared with that in the WT EAE mouse CNS. Moreover, the suppressive function of Cd226−/− Tregs was upregulated compared with that of WT Tregs. Furthermore, it was observed that the expression levels of CTLA-4 and TIGIT on Cd226−/− Tregs were higher than those on WT Tregs during EAE in the spleen and CNS. Our results demonstrate a pivotal role for CD226 in attenuating Treg function in EAE that was associated with downregulating the expression levels of CTLA-4 and TIGIT.  相似文献   
85.
86.
阿尔茨海默病(AD)是伴有认知功能障碍的神经退行性疾病,其发病机制复杂且至今不明确,一直是国内外医学研究领域的巨大挑战。而结构和扩散磁共振成像技术的发展,为研究AD大脑宏观形态学-微观结构特性病变的机制研究提供重要技术手段。近年来,研究发现,这种宏观和微观结构的异常改变之间具有的内在联系,对于揭示AD等衰老相关疾病的结构病变机理有非常重要的意义。针对该问题,对近几年MRI的大脑宏-微观结构变化模式及相互关系的研究进行分析,对其重要的分析方法和研究结论进行综述,希望有助于今后对大脑宏-微观病变机理的深入开展。  相似文献   
87.
Liang  Xiongyan  Gu  Yufang  Chen  Xueyang  Li  Tuofan  Gao  Yulong  Wang  Xiaomei  Fang  Chun  Fang  Shouguo  Yang  Yuying 《Virus genes》2019,55(5):726-733
Virus Genes - Avian leukosis virus (ALV) caused tremendous economic losses to poultry industry all over the world, especially in China. One natural recombinant ALV strain, designated as HB2015032,...  相似文献   
88.
Parasitology Research - Trypanosoma lewisi (Kinetoplastea: Trypanosomatida: Trypanosomatidae) with a cosmopolitan distribution is the type species of the subgenus Herpetosoma, which includes ca. 50...  相似文献   
89.
Efficient production of high‐quality, functionalized graphene is highly desirable for large‐scale applications of graphene. Herein, a route for producing high‐quality, polystyrene (PS)‐functionalized graphene is demonstrated via graphite exfoliation in chloroform with a heterobifunctional hyperbranched polyethylene, HBPE@Py@PS, as stabilizer. The HBPE@Py@PS, possessing a pyrene‐functionalized hyperbranched polyethylene backbone and multiple PS side chains, is synthesized by combining chain walking polymerization and atom transfer radical polymerization techniques. It is confirmed that the HBPE@Py@PS can effectively promote graphite exfoliation in chloroform under sonication to render stable dispersions of high‐quality graphene, with an exfoliation efficiency high as 15% and a monolayer proportion, 61%. Meanwhile, it can irreversibly adsorb on the exfoliated graphene surface based on the π–π stacking interactions, concurrently rendering PS‐functionalized graphene that is fluorescent and highly dispersible in chloroform, with a film conductivity reaching 1100 S m?1. The as‐produced graphene may find its applications as nanofiller for various PS‐based graphene nanocomposites.  相似文献   
90.
In the last several years, multiple‐shape memory liquid crystalline networks (LCNs) have received more and more attention due to the basic theoretical research on them and their wide potential applications. In this article, a novel main‐chain/side‐chain liquid crystalline monomer and its corresponding polymer networks based on the thiol‐ene click reaction are reported. Properties of the synthesized liquid crystalline monomer are well studied with nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR) spectra, differential scanning calorimetry (DSC), and polarized optical microscopy (POM). The as‐prepared free‐standing LCN films are investigated well by FTIR, DSC, POM, and X‐ray diffraction (XRD), which show them having good liquid crystalline properties. Tensile test and dynamical mechanical analysis (DMA) results indicate the LCN films have excellent thermal mechanical properties. By adjusting the crosslinking densities, LCN films exhibit two thermal transition temperatures (Tg and TNI) that can be utilized to trigger the triple‐shape memory behaviors. The cyclic thermal mechanical analysis conducted by DMA reveals that LCN films exhibit good triple‐shape memory properties with high‐shape fixity ratio (Rf (S1→S2) is 99.2% and Rf (S2→S3) is 99.3%) and shape recovery ratio (Rr (S3→S2) is 92.4% and Rr (S2→S1) is 98.5%).  相似文献   
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