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71.
黄芪甲苷预处理对无血清及缺氧诱导的骨髓间充质干细胞 TNF-α、TGF-β1基因表达的影响 总被引:1,自引:0,他引:1
目的:观察黄芪甲苷预处理对无血清及缺氧诱导的骨髓间充质干细胞(MSCs)凋亡相关因子的影响,并探讨其作用机制。方法采用密度梯度离心法分离培养大鼠 MSCs,通过药物细胞毒性试验检测黄芪甲苷对 MSCs 细胞活性的影响,分别以40、80、160μg / mL 的黄芪甲苷预处理 MSCs 24 h,后进行无血清及缺氧培养24 h,RT-PCR 法检测细胞中 TNF-α、TGF-β1的基因表达情况。结果密度梯度离心法可有效分离大鼠MSCs;各浓度黄芪甲苷对 MSCs 细胞活力均无影响;无血清及缺氧诱导可下调 TGF-β1的基因表达;160μg / mL黄芪甲苷组可上调 TGF-β1的基因表达。结论无血清及缺氧诱导的 MSCs 凋亡可能是由于缺氧及生长因子匮乏的刺激所引起的,黄芪甲苷抑制无血清及缺氧诱导的 MSCs 凋亡的作用可能是通过提高 MSCs 在缺血缺氧环境下合成生长因子的能力实现的。 相似文献
72.
目的 探讨重组E.coli. LLO/OVA 诱导C57BL/6小鼠机体免疫的途径,观察其免疫后小鼠机体抑制B16-OVA黑色素瘤的效果.方法 磁珠分离E.coli. LLO/OVA及E.coli. OVA免疫后小鼠脾脏CD11c、CD4 和CD8 T细胞并检测CD11c细胞诱导同源CD4 和CD8 T增殖水平和细胞因子分泌程度;流式细胞检测小鼠脾脏内肿瘤抗原OVA257-264 SIINFEKL特异的细胞毒T细胞含量.比较两种E.coli. 免疫后,恶性黑色素瘤B16-OVA在小鼠肺内形成瘤结节的数量.结果 与E.coli. OVA相比, E.coli. LLO/OVA免疫后小鼠脾脏CD11c细胞诱导同源CD4 T细胞增殖作用增强、IL-2分泌增高;同时诱导CD8 T细胞增殖和IFN-γ分泌的作用也明显增强;OVA257-264 SIINFEKL特异的CD8 T细胞含量也明显增高;小鼠肺内形成B16-OVA瘤结节平均数明显减少. 结论 E.coli. LLO/OVA有效地诱导小鼠CD11c细胞活化,增强其对CD4 T细胞增殖和IL-2分泌以及对CD8 T细胞增殖、IFN-γ分泌的作用,诱导了更多的OVA特异的CD8 T细胞,使机体产生了更强的抗肿瘤免疫. 相似文献
73.
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75.
张璨 《中国药理学与毒理学杂志》2012,(3):439
OBJECTIVE Alzheimer′s disease(AD) is mainly characterized by a progressive loss of neurons and the deposition of beta-amyloid peptides(Aβ).It was demonstrated that transplanted and endogenous neural stem cells or neural precursor cells can survive,migrate,and differentiate into neurons.Previously we found that Aβ42 could disturb the migratory ability of neural stem/precursor cells.We therefore hypothesized that Aβ42 may affect some important proteins through Rho pathway and result in the decreased migration of neural stem/precursor cells.METHODS AND RESULTS We applied siRNA technology to knock down the expression of RhoC in neural stem/precursor cells and found that the expression of RhoC was down-regulated;Trans well assay was used to measure the migratory ability of the neural stem/precursor cells and the result showed that the migratory ability was disturbed when the expression of RhoC was down-regulated;WRW4 was used for inhibiting the effects of the Aβ42 through the FPRL1.CONCLUSION The reduction of RhoC was involved in the decreased migration of neural stem cells. 相似文献
76.
M. Serbes D. Can F. Atlihan I. Günay S. Asilsoy S. Altinöz 《Allergologia et immunopathologia》2013,41(4):255-260
ObjectiveWe aimed to establish the characteristics of anaphylaxis in childhood.MethodsForty-four patients who had experienced anaphylaxis in a period of 10 years (from 1999 to 2009), were included in the study. Parameters analysed were age, gender, concomitant allergic disease, trigger, setting, clinical symptoms, treatment, prognosis and prophylaxis.ResultsThe total numbers of anaphylaxis cases were 44 in a ten-year period. The ages of patients ranged from 3 to 14 years (11.50 ± 3.87 years) and the majority were male. 33 of the patients (75%) had a concomitant allergic disease. The trigger was determined in 93.2% of the cases, being most frequent: food (27.3%), and SIT (25%), followed by bee sting, medications and others. Respiratory (95.5%), dermatological (90.9%), cardiovascular (20.5%), neuropsychiatric (25%), and gastrointestinal (11.4%) symptoms were seen most frequently. For anaphylaxis triggered by food, the duration of anaphylactic episode was significantly longer (p < 0.05). No biphasic reaction was observed during these attacks. Of our patients, only one developed respiratory failure and cardiac arrest due to SIT, and intensive care support was required.DiscussionAs a trigger for anaphylaxis, the frequency of SIT is so high that it cannot be described by the study group including patients who were followed up in an outpatient allergy clinic. 相似文献
77.
Ö. Bağ D. Can U. Karaarslan İ. Günay C.Ş. Turgut H.T. Nacaroğlu 《Allergologia et immunopathologia》2013,41(5):315-319
BackgroundProspective cohort studies have provided useful knowledge about the natural history of asthma. However, most of the studies are conducted in western countries but the course of the disease and long-term outcomes may differ between countries due to environmental and cultural factors.ObjectiveThe aim of this study is to describe the long-term outcomes of childhood asthma, with data from a follow-up study of at least 10 years, in western Anatolia, Turkey.MethodsFifty-two patients diagnosed with persistent allergic asthma participated in the study. The patient's demographics, findings on admission, age at onset of disease, time of diagnosis, history of other allergic conditions, history of parental asthma and allergic disorders, presence of pharmacotherapy and immunotherapy were obtained from patients’ records. The factors influencing remission at the end of 10 years follow-up were evaluated.ResultsA total of 20 patients (38.5%) were on remission at the end of 10 years. The type of allergen, multi-allergen sensitivity, eosinophilia and elevated serum immunoglobulin E on admission, accompanying allergic disorders and atopy in parents, and allergen immunotherapy did not affect the remission rate (p > 0.05).ConclusionChildhood persistent asthma is not a homogeneous clinical entity but high clinical remission rates are obtained in western Anatolia. There is no significant predictor of clinical remission in long term follow-up. Prospective studies should be performed in larger asthmatic populations to obtain further data about the natural course of childhood asthma. 相似文献
78.
We describe a Chinese woman who was assumed to be a Hb Q-Thailand heterozygote, but was later also shown to have β-thalassemia (β-thal) with a normal amount of Hb A2. 相似文献
79.
目的采用蛋白质组学技术探讨缺血预适应心肌内源性保护的分子机制。方法应用双向凝胶电泳技术分离假手术组和心肌缺血预适应延迟相组大鼠的心肌总蛋白质。结果在假手术组的双向凝胶电泳图谱上展示704±27个蛋白质点,而在心肌缺血预适应延迟相组展示778±35个蛋白质点。经凝胶图像分析找到的差异蛋白质23个,基质辅助激光解析—电离飞行时间质谱对差异蛋白进行鉴定,共鉴定出12个蛋白质。这些蛋白质包括应激反应蛋白、代谢相关蛋白、信号调节蛋白、结构蛋白等。结论这些差异蛋白可能通过其分子伴侣功能、清除自由基、改善能量代谢等发挥心肌缺血预适应延迟相的心肌保护作用。 相似文献
80.
医师资格考试是大多数国家普遍采用的医师资格认证形式。医学人文的考核在医师资格考试中占有重要地位。以临床类别考试为例,通过文献分析、比较研究的方法,比较分析中美两国执业医师资格考试和医师资格分阶段考试实证研究考试中的医学人文考核,包括考试内容和形式、考试分值及比例。发现两国医学人文考核内容和比例基本相当,但我国现行考试医学人文考核站数较少,考试形式和呈现方式有待进一步改善,下一步应继续探索标准化病人应用于我国医师资格考试的可行性,充分发挥医师资格考试对医学教育的导向作用。 相似文献