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81.
Jiang Bian Ting Wang Jijun Sun Xiaozhen He Zhijiao Wu Songmei Zhang Hao Chi Tingting Fan Shaowen Wang Weiyun Shi Qingguo Ruan 《American journal of transplantation》2021,21(12):3858-3870
The relevance of Tregs in the induction of tolerance against corneal allografts has been well established. Although it is well known that the conversion of Tregs into effector-like cells contributes to the loss of corneal immune privilege, the underlying mechanism is still not fully understood. Using heterologous penetrating keratoplasty model, we found that Tregs from corneal allograft rejected mice (inflam-Tregs) exhibit impaired function and characteristics of effector T cells. Further study showed that the expression of NF-κB c-Rel, a key mediator of effector T cell function, was significantly increased in inflam-Tregs. Mechanistic study revealed that elevated NF-κB c-Rel level in inflam-Tregs impaired Treg function through the promotion of inflammatory cytokine production and glycolysis. More importantly, we demonstrated that targeting NF-κB c-Rel was able to improve the immune suppressive function of inflam-Tregs in vitro and enhance the potential of them to suppress corneal transplantation rejection. Therefore, our current study identified NF-κB c-Rel as a key mediator of the conversion of Tregs into effector-like cells when under inflammatory environment. 相似文献
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目的 建立一种快速稳定的液质联用方法同时分析佛耳草中17种化学成分的含量,为完善佛耳草质量标准提供实验依据。方法 采用超高效液相色谱-四极杆/静电场轨道阱质谱法(UPLC-Q-Exactive Orbitrap MS)对15批不同产地佛耳草中的17种成分进行定量分析,使用ACQUITY UPLC? BEH C18色谱柱(2.1 mm×100 mm,1.7 μm),以甲醇(A)-0.1%甲酸水溶液(B)为流动相梯度洗脱(0~1.0 min,8%A;1.0~4.0 min,8%~26%A;4.0~9.0 min,26%A;9.0~14.0 min,26%~34%A;14.0~14.5 min,34%~45%A;14.5~15.0 min,45%~60%A;15.0~18.0 min,60%~90%A;18.0~19.0 min,90%A;19.0~19.01 min,90%~8%A;19.01~20.0 min,8%A),流速0.3 mL·min-1,柱温40 ℃,进样量2 μL;运用电喷雾离子源,正、负离子模式全扫描,扫描范围m/z 100~1 000。结果 所建立的测定方法经方法学验证良好,能够用于17种成分的同时定量。15批佛耳草样品中奎宁酸、没食子酸、原儿茶酸、新绿原酸、绿原酸、隐绿原酸、咖啡酸、1,3-O-二咖啡酰奎宁酸、异绿原酸A、异槲皮苷、1,5-O-二咖啡酰奎宁酸、大波斯菊苷、紫云英苷、异绿原酸C、木犀草素、芹菜素、高车前素的质量范围依次为39.60~179.12、0.17~0.84、2.41~8.38、4.33~31.50、13.63~180.38、2.43~14.75、1.16~19.68、0.49~5.63、55.77~445.16、0.23~10.26、62.04~530.10、1.11~18.01、11.36~90.61、12.22~65.98、7.22~69.84、3.37~45.65、0.30~2.59 μg·g-1,其中有机酸类成分在佛耳草中含量比黄酮类成分更高,以1,5-O-二咖啡酰奎宁酸、异绿原酸A、奎宁酸、绿原酸含量较高,同时,贵州产地佛耳草样品中黄酮类成分含量高于江苏产地样品,江苏产地佛耳草样品中有机酸类成分含量则高于贵州产地样品。结论 建立的检测方法可用于佛耳草中17种成分含量的快速、准确测定,明确了佛耳草主要成分的含量范围,可为佛耳草质量控制标志物的选择提供参考。 相似文献
85.
Existing criteria for admission of newborns to the special care nursery, Sarawak General Hospital, resulted in the admission of many neonates with certain risk factors ("at risk" neonates). To test whether such babies could be safely and better cared for in postnatal wards, 392 of these babies were randomly allocated into two groups. One group of 196 was admitted to the special care nursery and the other group of 196 was cared for with their mothers in the postnatal wards. The two groups were compared for mortality, morbidity and breastfeeding. There was no significant difference in mortality and morbidity between the two groups. While in hospital a larger proportion of babies cared for in postnatal wards were breastfed, compared to babies admitted to the special care nursery. In addition, they initiated their breastfeeding earlier. Babies with these risk factors should therefore be cared for with their mothers in the postnatal wards. 相似文献
86.
半导体激光穴位照射的镇痛作用及其机制初探 总被引:2,自引:0,他引:2
目的 探讨半导体激光穴位照射镇痛效应及其镇痛的机制。方法 大鼠随机分成照射组、模拟照射组和纳洛酮预处理组。采用半导体激光照射大鼠“足三里”穴位 ,用电刺激鼠尾 -嘶叫法测定激光照射前后的痛阈。结果 照射后大鼠的痛阈明显提高 ,这种镇痛作用可被纳洛酮预处理所翻转。结论 半导体激光穴位照射产生镇痛效应机制可能与激光照射促进内源性阿片物质释放有关。 相似文献
87.
小学生学习困难综合干预前瞻性研究 总被引:6,自引:2,他引:4
目的 验证综合干预治疗小学生学习困难(LD)的效果。方法 84例LD学生分成干预组(43例)和不干预组(41例)作对照,用教育、家庭、学校干预和心理治疗及药物治疗进行综合干预。结果 二年后,干预组有效率(76.74%)、学习成绩及智商明显高于不干预组,LD和行为问题发生率明显低于后者(P〈0.05~0.01)。结论 综合干预是通过增强学生学习自信心,减少或消除心理行为问题,提高智力水平等综合发挥效 相似文献
88.
Ke Li Jin Shi Xin Liu Michael P. Ward Zengliang Wang Rui Liu Zheng Zhao Yun Yin Yuanhua Liu Jie Hong Jiaqi Huang Xi Chen Zhijie Zhang 《Journal of medical virology》2023,95(1):e28341
The Omicron variant has become the dominant COVID-19 variant worldwide due to its rapid and cryptic spread. Therefore, successful early warning is of great importance to be able to control epidemics in their early phase, before developing into large outbreaks. COVID-19-related Baidu search index, which reflects human behavior to a certain degree, was used to retrospectively detect the warning signs for Omicron variant outbreaks in China in 2022. The characteristics and effects of warning signs were analyzed in detail. We detected the presence of early warning signs (both high and low thresholds) and found that these occurred 4–7 days earlier than traditional epidemiological surveillance and >20 days earlier than the implementation of the local “lockdown” policy. Compared with the “high threshold” warning, the early warning effect of the “low threshold” is also vital because it indicates a negligence about epidemic prevention and control. However, there is obvious heterogeneity in the optimal threshold for detecting early warning signs and their distribution in different cities. Multi-source and multi-point early warning systems should be established via combining internet-based big data in the future to conduct effective and early real-time warning. This would create precious time for the early control of COVID-19 outbreaks. 相似文献
89.
Recombinant human epidermal growth factor (rhEGF), a polypeptide of 53 amino acid residues, is subject to degradation by numerous
enzymes, especially proteases, when it is applied on the skin for the treatment of open wound. Amastatin, aprotinin, bestatin,
EDTA, EGTA, gabexate, gentamicin, leupeptin, and TPCK were investigated for the possible protease inhibitors, which may use
to protect rhEGF from degradation by the enzymes in the skin. Skin homogenates containing protease inhibitors and rhEGF were
incubated at 37°C for 30 minutes. After the reaction was stopped with trifluoroacetic acid, the amount of rhEGF remaining
in the sample was determined with an HPLC method. The percentages of rhEGF degraded, at the skin/PBS ratio of 0.25, in the
mouse, rat, and human skin homogenate were 85%, 70%, and 46%, respectively. The degree of degradation of rhEGF in the cytosolic
fraction was higher than that in the membrane fraction and these enzyme reactions were completed in 30 minutes. Bestatin,
EGTA, and TPCK showed significant inhibitory effects on the degradation of rhEGF in the two fractions (p<0.05), while the
other protease inhibitors had no significant inhibitory effects or, even resulted in deleterious effects. Therefore, the formulation
containing one or several inhibitors among these effective inhibitors would be a promising topical preparation of rhEGF for
the treatment of open wound. 相似文献
90.
环枕关节脱位:附二例报告 总被引:1,自引:0,他引:1
环枕脱位十分少见。此种病例,由于环枕部结构复杂,照片显示常不够清楚。人们往往只注住只注意环枢椎的关系而对环枕脱位的警惕性不足,容易漏诊,其后果是严重的。本文报道两例环枕关节脱位病例,并对该病的病因、发病机制、局部解剖、合并症及其诊断要点进行分析,并提出“斜坡-齿突线”对本病的诊断有重要意义。 相似文献