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21.
The purpose of this study was to examine the mediating and moderating roles of resilience on the relationship between perceived stress and depression among heroin addicts. A total of 138 heroin addicts completed the measures of perceived stress, resilience, and depression. Correlation analysis indicated that perceived stress was positively associated with depression. Resilience was negatively correlated with perceived stress and depression. Mediation analysis revealed that resilience partially mediated the relationship between perceived stress and depression. However, resilience did not moderate the influence of perceived stress on depression. These findings might provide a better understanding of the mental health among heroin addicts.  相似文献   
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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   
24.
Song  In Hye  Kim  Young-Ae  Lee  Hyeonjin  Park  Hye Seon  Park  In Ah  Sim  Chan Kyu  Lee  Myeong Sup  Gong  Gyungyub  Lee  Hee Jin 《Immunologic research》2019,67(6):469-477
Immunologic Research - The expression of major histocompatibility complex class I (MHC I) in tumor cells is regulated by interferon signaling, and it is an important factor in the efficacy of...  相似文献   
25.
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   
26.
BackgroundTo determine whether 3D-CT imaging technique is valid and reproducible compared to conventional CT measurement technique (CCT) for the detection of a femoropatellar instability.MethodsPatients who had undergone surgery for femoropatellar instability (patellar instability group) between 2010 and 2016 (n = 37 knees of 35 patients) were retrospectively enrolled. For the matched control group, patients who had acute anterior cruciate ligament injury (< 4 weeks previously; n = 30) were recruited. Preoperative CT data had been obtained in all patients. Inter-rater reliability was calculated for both measurement protocols, and inter-method reliability was calculated between the two imaging modalities. The results are reported using intraclass correlation coefficients (ICCs) and Bland–Altman 95% limits of agreement.ResultsAll patients in the patellar instability group had femoral trochlear dysplasia (Dejour types A: four, B: 19, C: seven, and D: six), but no dysplasia was noted in the control group. In the patellar instability group, the CCT technique showed a poor inter-rater agreement (ICC = 0.74), and the 3D-CT technique still showed excellent inter-rater agreement (ICCs = 0.91). In the sub-analysis of the patellar instability group according to the trochlear dysplasia grade, ICCs were markedly decreased with severe trochlear dysplasia when using CCT technique; however, the 3D-CT technique could provide excellent reliability even with severe trochlear dysplasia.ConclusionThe 3D-CT imaging technique for the measurement of the TT–TG distance can be suggested as a better measurement technique for patellar instability patients with bone abnormality.  相似文献   
27.
Wang  Rui  Li  Na  Jiang  Wen  Guo  Yaqiong  Wang  Xiaolan  Jin  Yue  Feng  Yaoyu  Xiao  Lihua 《Parasitology research》2019,118(10):3053-3060

The infection patterns and clinical significance of Enterocytozoon bieneusi and Giardia duodenalis in dairy cattle remain poorly investigated despite their common occurrence. Data on the genetic diversity are also needed to understand the transmission and human-infective potential of the two pathogens. In this study, fecal specimens from 1366 dairy cattle on a large farm were examined for the presence and genotype distribution of E. bieneusi and G. duodenalis by PCR and DNA sequencing. The overall infection rates of E. bieneusi and G. duodenalis were 13.0% and 20.6%, respectively. Pre-weaned calves had significantly higher infection rates of both pathogens than post-weaned and adult cattle (P < 0.001), with peak occurrence of the pathogens in animals of 7–12 weeks. In both pre- and post-weaned calves, animals with diarrhea were 2.1–3.0 times more likely to be infected with either pathogen than those without diarrhea (P < 0.01). The E. bieneusi identified belonged to five genotypes, including J (n = 138), I (n = 21), BEB4 (n = 10), Type IV (n = 1), and a novel genotype CHC17 (n = 1). Genotype J was the dominant one in all age groups, whereas genotype I was only identified in calves of 6–11 weeks. Genotyping of G. duodenalis at three genetic loci identified assemblage E (n = 278), assemblage A (n = 2), and concurrence of the two (n = 1). Altogether, 13, 7 and 10 subtypes of assemblage E were detected at the bg, gdh, and tpi loci, respectively, forming 65 multilocus genotypes. The formation of two major clusters of MLGs in eBURST analysis indicated that intra-assemblage genetic recombination of two dominant MLGs could have led to the high genetic heterogeneity within assemblage E on a single farm. Results of this study provide much needed data on the pathogenicity of E. bieneusi and G. duodenalis in pre- and post-weaned calves. The clinical significance of the two pathogens in dairy cattle warrants further investigations.

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28.
Cellulose is a kind of natural polymer material, which is composed of bundle-like fibrils. By peeling the fibrils layer by layer, the size of cellulose can be nanocrystallized, and nanofibers and nanocrystals with unique and potentially useful features can be prepared. As an emerging functional polymer material, nanocellulose has become a research hotspot in the field of technology. This review discusses the preparation of nanocellulose, including the commonly used hydrolysis, oxidation, physical and environmentally friendly ionic liquid methods. The advantages and disadvantages of different methods are also compared. And the review introduced the application of nanofiberized cellulose and nanocellulose crystals in the fields of thermosetting and thermoplastics, such as polylactic acid, polypropylene, epoxy resin and so on. The critical factors in the manufacturing of nanocellulose composites and mechanical properties are discussed to provide a reference for the further application and development of nanocellulose.  相似文献   
29.
目的颈动脉粥样硬化斑块的形成是脑血管病变的独立危险因素之一。对颈动脉内膜剥脱术(carotid endarterectomy,CEA)斑块进行充分的组织学判读和研究,将有助于全面把握CEA斑块的组织学表现,进而推进临床辅助诊断。方法本文我们将运用数字病理扫描仪对CEA斑块的切片经H&E染色后进行扫描,介绍数字病理扫描在CEA斑块组织学研究中的应用。结果经数字病理扫描所得的图片,有助于全面掌握和保存CEA斑块组织切片的全层面信息;在软件的帮助下有助于非常方便地测量斑块内各成分的大小;有助于精确评估斑块的狭窄程度。结论综上,数字病理成像应用于CEA斑块,结合MRI,有助于高效且准确地判读斑块组成和预测斑块稳定性,亦有助于人工智能的训练。  相似文献   
30.
Injectable self‐healing hydrogels have drawn growing attention for their extensive applications in biomedical fields. Hydrogels containing nanoparticles also exhibit promising potentials in catalysis, wastewater treatment, and organic synthesis. Inspired by the multifunction of gallol presented herein, a simple one‐pot method to produce a gallol‐tethered gelatin hydrogel via Schiff base under oxidizing conditions using various oxidants is presented. The hydrogels prepared by NaIO4‐induced cross‐linking present a high self‐healing rate (up to 84.5%), injectable ability, tunable mechanical property, flexible viscoelasticity, and macroporous structure owing to the combination of covalent cross‐linking and supramolecular interactions. HAuCl4 contributes to the 3D structure formation of the gelatin hydrogel via oxidation cross‐linking. It is reduced by the gallol groups to produce nanogold (AuNP)‐decorated hydrogel (Au‐gel). This Au‐gel is fully characterized by UV–vis, XRD, TEM, SEM, EDX, and ICP‐MS and exhibits a high‐catalytic activity for the reduction of 4‐nitrophenol. The solid Au‐gel catalyst is robust, easily recyclable, and reused at least eight times.  相似文献   
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