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51.
目前,国内外肝移植学界对肝移植术后急性排斥反应(AR)的机制阐释为T细胞介导的细胞免疫应答,但为获得长期生存仍需长期乃至终身服用免疫抑制剂。即使如此,临床上AR仍时有发生,并导致相当一部分受者移植肝功能丧失,更重要的是受者术后还受到感染、肿瘤和其他一系列不良反应及沉重经济负担的影响。因此,为肝移植AR机制提出新的理论解释,更全面深入阐明肝移植免疫排斥反应的内在机制,进而依据新的机制研制出新型免疫抑制剂已势在必行。本文就B细胞介导的体液免疫应答在肝移植AR中的作用作一综述。  相似文献   
52.
目的 运用知识点模块网格化构建带教模型,观察其在肾内科实习生中的应用效果。方法 根据《内科学》(第八版)肾内科教学大纲要求,结合肾内科病房常见病、多发病的临床特点,精心挑选相关知识点,以理论为支撑点,以服务于实习带教工作为靶目标,各个知识点之间有临床的关联性,最终形成网格化的诊治分 析模型。将血尿、蛋白尿、高血压、水肿、肾小球滤过率为切入点,设定肾病综合征、系统性红斑狼疮、糖尿病肾病和急、慢性肾功能衰竭为临床知识必须掌握点,从病史、症状、体征和实验室检查几方面来培养实习生的诊疗思维,并通过知识点来关联疾病的诊治,从而帮助他们在有限的肾内科实习期间尽可能掌握肾内科临床知识。结果 本研究开展一年以来,对于来肾内科轮转的51 名实习生进行了模块网格化模型训练,实习生普遍反映该模型有很好的学习效果,让他们了解了肾内科临床重点,并能和理论学习的知识点有机融合在一起,开阔了实习生的诊疗视野,也便于对其他科知识点的学习。结论 基于知识点模块网格化,构建模型在肾内科实习生中有很好的带教作用,学生接受肾内科知识点的记忆增强,并能进一步推广到内科其他内容的实习带教中。  相似文献   
53.
Discoid lupus erythematosus (DLE) is the most common skin manifestation of lupus; however, the molecular mechanisms underlying DLE remain unknown. Therefore, we aimed to identify key differentially expressed genes (DEGs) in discoid lupus skin and investigate their potential pathways.To identify candidate genes involved in the occurrence and development of the disease, we downloaded the microarray datasets GSE52471 and GSE72535 from the Gene Expression Database (GEO). DEGs between discoid lupus skin and normal controls were selected using the GEO2R tool and Venn diagram software (http://bioinformatics.psb.ugent.be/webtools/Venn/). The Database for Annotation, Visualization, and Integrated Discovery (DAVID), Enrichr, and Cytoscape ClueGo were used to analyze the Kyoto Encyclopedia of Gene and Genome pathways and gene ontology. Protein-protein interactions (PPIs) of these DEGs were further assessed using the Search Tool for the Retrieval Interacting Genes version 10.0.Seventy three DEGs were co-expressed in both datasets. DEGs were predominantly upregulated in receptor signaling pathways of the immune response. In the PPI network, 69 upregulated genes were selected. Furthermore, 4 genes (CXCL10, ISG15, IFIH1, and IRF7) were found to be significantly upregulated in the RIG-I-like receptor signaling pathway, from analysis of Enrichr and Cytoscape ClueGo.The results of this study may provide new insights into the potential molecular mechanisms of DLE. However, further experimentation is required to confirm these findings.  相似文献   
54.
Dear Editor,Conjunctival cyst of the orbit acquired from enucleation is an infrequent but serious complication;which can occur in 3%-7%of patients,more commonly after a secondary procedure;.The most common manifestations are the inability to retain the external prosthesis.  相似文献   
55.

Aim

Leukocyte-associated immunoglobulin-like receptor-1 (LAIR-1) is an immune inhibitory receptor which is expressed within most types of hematopoietic cells and negatively regulates immune responses. Recently, we found LAIR-1 expression to be present within tumors of nonhematopoietic lineages. However, the roles of LAIR-1 in hepatocellular carcinoma (HCC) have yet to be examined. The purpose of this study was to investigate the expression of LAIR-1 in HCC tissue and assess its clinical significance at this site.

Materials and methods

Expression levels of LAIR-1 within HCC samples collected from 90 patients and compared with that of slides of normal liver tissue collected from 9 non-HCC patients were measured by immunohistochemistry using tissue microarrays. A semiquantitative score was assigned, as was based on staining intensity and percent of positive cells and a Spearman Rank correlation test was used to assess any potential significant correlations between LAIR-1 expression and clinicopathological factors. Overall survival analysis was performed using the Kaplan-Meier and Log Rank statistical test.

Results

LAIR-1 expression was detected in cancer tissue and adjacent tumor tissue, but not in normal liver tissue. The percent of LAIR-1-positive expression in cancer tissue of HCC samples was 97.78% (88/90) while that in adjacent tumor tissue was 96.67% (87/90). Significantly greater expression levels of LAIR-1 were obtained from cancer tissue (Mean?±?SD?=?5.722?±?2.145) than that in adjacent tumor tissue (4.141?±?1.486). In addition, LAIR-1 expression was found to be significantly correlated with pathological grade of HCC, T stage, and age. Expression levels of LAIR-1 were related with worse overall survival rates of HCC patients, especially in HCC patients with hepatic cirrhosis.

Conclusion

Results of this study show that LAIR-1 is expressed in HCC tissues and that high levels of LAIR-1 expression are associated with the poor cancer differentiation. In addition, overexpression of LAIR-1 was significantly associated with worse overall survival in the patients with HCC. These data suggest that LAIR-1 may be an independent predictor for clinical outcomes in patients with HCC.  相似文献   
56.
目的 运用网状Meta分析方法评价针灸联合关节松动术治疗肩周炎的疗效。方法 运用计算机检索Web of Science、PubMed、Cochrane Library、EMbase、维普(VIP)、中国知网(CNKI)、万方(Wanfang)、中国生物医学文献数据库(CBM),搜寻有关针灸联合关节松动术治疗肩周炎的随机对照试验。所有研究人员均独立纳排文献、提录资料、风险评估,对符合质量标准的RCT研究采用Stata16.0和Review Manager 5.4软件进行分析。结果 共检索出6561篇文献,最终纳入37项研究,涉及10种针灸联合关节松动术方法。总样本量2890例,其中试验组1432例,对照组1458例。网状Meta分析所得结果表明:①在总有效率方面,最好的3种治疗方法为内热针联合组、温针联合组、动筋针联合组;②在降低VAS评分方面,最好的3种治疗方法为内热针联合组、动筋针联合组、针刀联合组。结论 针灸联合关节松动术治疗肩周炎疗效总体优于单独使用,且内热针联合组具有最佳的疗效。  相似文献   
57.
58.
Stellate ganglion (SG) modification has been investigated for arrhythmia treatment. In this study, transesophageal SG imaging and intervention were explored using a homemade 30F integrated focused ultrasonic catheter in healthy mongrel canines in vivo. Anatomic details of SGs were ultrasonically imaged and evaluated. SG had a heterogeneous echoic structure and characteristic profiles sketched by hyper-echoic outlines in an ultrasonogram. Left SGs in the experimental group were successfully ablated through the esophagus under ultrasonic guidance provided by the catheter itself. Two weeks after the ablation, the QT and QTc of the experimental group decreased compared with those of the sham group and at baseline (both p values < 0.001). Histologic examination revealed that left SGs were destroyed. No major complications were observed. This approach may be further explored as a method for ganglia remodeling evaluation and as a strategy of ganglia modification for arrhythmia and for other diseases.  相似文献   
59.
Microglia, the innate immune cells of the CNS, perform critical inflammatory and noninflammatory functions that maintain normal neural function. For example, microglia clear misfolded proteins, elaborate trophic factors, and regulate and terminate toxic inflammation. In Alzheimer’s disease (AD), however, beneficial microglial functions become impaired, accelerating synaptic and neuronal loss. Better understanding of the molecular mechanisms that contribute to microglial dysfunction is an important objective for identifying potential strategies to delay progression to AD. The inflammatory cyclooxygenase/prostaglandin E2 (COX/PGE2) pathway has been implicated in preclinical AD development, both in human epidemiology studies and in transgenic rodent models of AD. Here, we evaluated murine models that recapitulate microglial responses to Aβ peptides and determined that microglia-specific deletion of the gene encoding the PGE2 receptor EP2 restores microglial chemotaxis and Aβ clearance, suppresses toxic inflammation, increases cytoprotective insulin-like growth factor 1 (IGF1) signaling, and prevents synaptic injury and memory deficits. Our findings indicate that EP2 signaling suppresses beneficial microglia functions that falter during AD development and suggest that inhibition of the COX/PGE2/EP2 immune pathway has potential as a strategy to restore healthy microglial function and prevent progression to AD.  相似文献   
60.
植物药对结肠癌具有良好的防治作用。姜黄素、多糖(苹果多糖、香菇多糖)、皂苷(重楼皂苷、人参皂苷)、白藜芦醇、槲皮素等植物药可通过不同信号通路抑制结肠癌细胞的增殖,促进细胞凋亡。此外,植物药还具有抗炎、抗氧化、抗血管生成、减轻化疗药物不良反应、逆转肿瘤细胞耐药等作用。了解植物药对结肠癌的防治作用及其可能的作用机制,能为结肠癌的临床防治提供更多的理论依据及治疗思路。  相似文献   
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