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51.
何丹  马建华  马娟  杜磊  张艳  郝晨光 《中国全科医学》2023,26(20):2513-2517
背景 调节性B淋巴细胞(Breg)是一类具有负向免疫调节作用的细胞,在多种自身免疫性疾病中表达异常,视神经脊髓炎谱系疾病(NMOSD)系自身免疫性疾病,目前关于Breg在NMOSD患者外周血中的表达和意义的研究较少。目的 研究Breg在NMOSD患者外周血中的表达和意义。方法 选取2019年6月—2021年12月新疆医科大学第一附属医院神经内科收治的NMOSD患者55例作为NMOSD组,选取同期本院体检正常的健康志愿者50例作为对照组。运用流式细胞仪检测两组研究对象外周血中CD19+CD24hiCD38hi Breg、CD19+CD24hiCD27+Breg的表达。采用酶联免疫吸附测定(ELISA)法检测和比较两组研究对象血清中白介素10(IL-10)、白介素35(IL-35)和转化生长因子β1(TGF-β1)的水平。结果 NMOSD组患者CD19+CD24hiCD38hi Breg、CD1...  相似文献   
52.
目的 探讨酪酸梭菌活菌散对支气管哮喘患儿辅助性T细胞17(Th17细胞)、调节性T细胞(Tr细胞)及其相关细胞因子和肠道菌群的影响。方法 选择2018年3月至2020年6月新乡医学院第三附属医院收治的97例支气管哮喘患儿为研究对象,根据治疗方法将患儿分为观察组(n=49)和对照组(n=48)。对照组患儿给予吸入用布地奈德混悬液、吸入用异丙托溴铵溶液和孟鲁司特钠颗粒治疗;在对照组治疗基础上,观察者组患儿给予酪酸梭菌活菌散治疗,2组患儿均治疗2个月。应用流式细胞仪检测2组患儿治疗前后Th17细胞和Tr细胞水平,并计算Th17细胞与Tr细胞的比值(Th17/Tr);采用酶联免疫吸附试验检测2组患儿治疗前后血清中白细胞介素-17(IL-17)、白细胞介素-10(IL-10)水平。使用儿童肺功能仪检测2组患儿治疗前后第1秒用力呼气容积(FEV1)、FEV1/用力肺活量(FVC)、呼气流量峰值(PEF)日变异率;分别于治疗前后收集并培养2组患儿新鲜粪便,观察肠道菌群分布情况。治疗期间观察2组患儿不良反应发生情况,治疗后评估患儿临床疗效;所有患儿治疗后随访...  相似文献   
53.
免疫系统可识别、抵抗病原微生物及清除体内异常分裂的细胞,平衡的免疫系统对维持正常的机体反应活动至关重要。人体内的多种细胞都可参与维持免疫稳态,其中辅助性T淋巴细胞17(Th17)和调节性T淋巴细胞(Treg)发挥着重要作用,失衡的免疫系统可致多种免疫性疾病的发生。Th17/Treg细胞平衡受细胞因子、代谢、肠道微生态及翻译后修饰等多种机制调控,该文通过总结相关机制为免疫性疾病治疗提供新思路和策略。  相似文献   
54.
Chronic experiments on cats showed that analgesics, in subanalgesic doses, not only exhibit an antinociceptive effect when accompanied by subthreshold stimulation of the mesencephalon, but also potentiate the analgesic action of central stimulation. Tranquilizers only facilitate the development of an analgesic effect during subthreshold mesencephalic stimulation. The possible reasons for differences in the action of these substances are discussed.Department of Pharmacology, I. P. Pavlov First Leningrad Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR S. V. Anichkov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 1, pp. 36–41, January, 1978.  相似文献   
55.
We addressed the question of whether allo-transplantation (Tx) induces breakdown of tolerance to self-antigens or alteration of the autoreactive T cell repertoire in humans. The serial variation of T cell autoreactivity was studied in the peripheral blood of 12 renal transplant patients, by autologous limiting dilution assay and autologous mixed lymphocyte reaction. Ten of 12 patients presented a positive response in autologous peripheral blood mononuclear cells in the post-Tx period, in contrast to four of 12 patients before Tx (P = 0.038). Multi-hit kinetics was found in 57% of the assays analyzed, indicating frequent regulatory control of the autologous response. Quantitative analysis performed in eight patients showed an increase in precursor frequency at >1 year post-Tx in five patients. These data indicate that autoreactivity increases or develops following Tx, in humans. Post-Tx events such as alloreactivity, infections or immunosuppression could interfere with the balance of autoreactive and regulatory cells, leading to changes in the T cell repertoires to self-antigens and eventually breakdown of self-tolerance. Further investigation is needed to elucidate whether post-Tx autoreactivity contributes to rejection, plays a regulatory role over alloreactivity or both, at separate times.  相似文献   
56.
57.
Recent data demonstrated that CD4+CD25+ regulatory T (Treg) cells and an enzyme called indoleamine 2,3-dioxygenase (IDO) mediate maternal tolerance to the fetus. Interestingly, Treg cells express the CTLA-4 molecule on their surface, and B7 (CD80/86) ligation by CTLA-4 enhanced IDO activity of dendritic cells (DCs) and monocytes by the induction of interferon gamma (IFN-gamma) production. In this study, we studied the IDO expression on peripheral blood monocytes and decidual monocytes or DCs after treatment with CTLA-4/Fc fusion protein or IFN-gamma using flow cytometry. IDO expressions on both peripheral blood DC and decidual DC and monocytes were up-regulated during normal pregnancy. On the other hand, both IDO expression on DC and monocytes after IFN-gamma treatment or CTLA-4 treatment were decreased in spontaneous abortion cases. The expression of CD86 on peripheral blood and decidual monocytes and DC in spontaneous abortion cases was lower compared with those in normal pregnancy subjects. Also, IFN-gamma production by decidual and peripheral blood mononuclear cells after CTLA-4/Fc treatment in spontaneous abortion cases was significantly lower than those in normal pregnancy subjects. These data suggest that CTLA-4 on Treg cells up-regulates IDO expression on decidual and peripheral blood DC and monocytes by the induction of IFN-gamma production.  相似文献   
58.
The influence of family relations, maternal occupational characteristics, and childcare1The UK terms "childcare," childcare centres' and "nurseries" are used throughout this paper to define group care for children prior to starting their first year of formal schooling at age 4 years and are used synonymously with the American terms "day-care" and "preschool." This form of group care is provided in a formal setting, outside the family home and excludes "childminding" (i.e., childcare that may be group based and offered at the home of the care provider/childminder). In the UK, this form of childcare is offered from zero to 4 years old. Children are separated according to their age into small groups usually consisting of 10-15 children. In the present study, all children were in the preschool-aged group (3-4 years old). Where childcare of a different or more generic form is referred to, then this has been made clear in the context or stated in the text. utilization on preschool children's cortisol production were investigated in 56 mother-child dyads. Family characteristics and maternal employment, childcare and child temperament were reported by mothers. Morning and evening levels of children's salivary cortisol were obtained. Children in highly expressive or reserved families exhibited higher cortisol levels compared to children in moderately expressive families. Elevated levels of cortisol were detected in children of mothers reporting low levels of job role quality or high levels of emotional exhaustion. Frequent childcare use was found to protect children against the physiological effects of low maternal job role quality and emotional exhaustion. Findings underscore the pervasive role of the family as set within an external support system and highlight the potential physiological impact of these interacting contexts for children. Further research is needed to fully understand current findings and to develop appropriate psycho-physiological interventions.  相似文献   
59.
Acute emotional stress caused by immobilization and cutaneous electrical stimulation increases the relative weight of adrenals in Wistar rats and decreases it in August rats. The epinephrine and norepinephrine contents of the adrenals in control and stressed August rats are higher than in Wistar rats. Acute stress lowers the levels of these biogenic amines in the adrenals of both strains, particularly in Wistar rats. The left adrenal gland of control and stressed August rats, but not of Wistar rats, has a higher content of biogenic amines than the right, and both adrenals of stressed August rats contained higher dopamine concentrations than those of stressed Wistar rats. Presumably, epinephrine and norepinephrine are resynthesized in the adrenals of stressed August rats at higher rates than they are released from these glands, while the adrenals of Wistar rats respond to stress by rapidly releasing these catecholamines and resynthesizing them at a slow rate. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 123, No. 6, pp. 645–648, June, 1997  相似文献   
60.
Although fathers perpetrate a significant proportion of child maltreatment, the intervention needs of abusive and neglectful fathers have not been adequately addressed or researched. This paper argues that well-designed treatment has the potential to benefit men, their children, and their families. However, the treatment needs of maltreating and at-risk fathers are unique, and programs must be designed accordingly. Based on the integration of parenting, child abuse, change promotion, and batterer treatment literatures, five principles to guide intervention with maltreating fathers are advanced: (a) overly controlling behavior, a sense of entitlement, and self-centered attitudes are primary problems of abusive fathers; thus, the development of child-management skills should not be an initial focus of intervention; (b) abusive fathers are seldom initially ready to make changes in their parenting; (c) fathers' adherence to gender-role stereotypes also contributes to their maltreatment of children; (d) the relationship between abusive fathers and the mothers of their children requires special attention; and (e) because abusive fathers have eroded children's emotional security, the need to rebuild trust will affect the pace of change and potential impact of relapse on the child. These principles are contrasted with the supportive and child-management goals of conventional group parenting programs, and the implications for providing service to fathers are considered.  相似文献   
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