泄浊解毒方对溃疡性结肠炎大鼠IL-10、TNF-α及NF-κB表达的影响

目的:观察泄浊解毒方对溃疡性结肠炎大鼠白介素-10(IL-10)、肿瘤坏死因子-α(TNF-α)及核因子-κB(NF-κB)表达的影响并探讨其作用机制。方法:2,4,6-三硝基苯磺酸(TNBS)/乙醇溶液灌肠制备溃疡性结肠炎大鼠模型,实验设正常组、模型组、柳氮磺胺吡啶组、中药泄浊解毒方小、大剂量组;观察大鼠结肠病理形态学改变(DAI评分及CMDI评分),采用放射免疫法测定细胞因子IL-10、TNF-α,运用免疫组化染色(SP法)检测NF-κBp65表达。结果:泄浊解毒方可明显降低大鼠结肠DAI及CMDI评分,减少NF-κBp65表达,增加IL-10含量,降低TNF-α的含量。结论:泄浊解毒方对大鼠溃疡性结肠炎有良好的治疗作用,其作用机制可能与减少NF-κBp65表达,增加IL-10含量,降低TNF-α的含量有关。     

行动导向教学模式在中升本老年护理学实验教学中的应用

探讨行动导向教学模式在中升本老年护理学实验教学中的应用,结合中升本学生专业技能的优势和特点,进行课程设置优化。该模式的构建充分体现了以学生为主体,以教师为主导的教学理念,是一种适合中升本学生特点的护理实验教学模式。     

Distinct segregation of the pathogenic m.5667G>A mitochondrial tRNAAsn mutation in extraocular and skeletal muscle in chronic progressive external ophthalmoplegia

Chronic progressive external ophthalmoplegia (CPEO) is a frequent clinical manifestation of disorders caused by pathogenic mitochondrial DNA mutations. However, for diagnostic purposes skeletal muscle tissue is used, since extraocular muscle tissue is usually not available for work-up. In the present study we aimed to identify causative factors that are responsible for extraocular muscle to be primarily affected in CPEO. We performed comparative histochemical and molecular genetic analyses of extraocular muscle and skeletal muscle single fibers in a case of isolated CPEO caused by the heteroplasmic m.5667G>A mutation in the mitochondrial tRNA^Asn gene (MT-TN). Histochemical analyses revealed higher proportion of cytochrome c oxidase deficient fibers in extraocular muscle (41%) compared to skeletal muscle (10%). However, genetic analyses of single fibers revealed no significant difference either in the mutation loads between extraocular muscle and skeletal muscle cytochrome c oxidase deficient single fibers (extraocular muscle 86% ± 4.6%; skeletal muscle 87.8 %± 5.7%, p = 0.246) nor in the mutation threshold (extraocular muscle 74% ± 3%; skeletal muscle 74% ± 4%). We hypothesize that higher proportion of cytochrome c oxidase deficient fibers in extraocular muscle compared to skeletal muscle might be due to facilitated segregation of the m.5667G>A mutation into extraocular muscle, which may explain the preferential ocular manifestation and clinically isolated CPEO.     

试验设计类型之无法考察交互作用的多因素设计:嵌套设计

本文目的是介绍一种无法考察交互作用的多因素设计类型,即嵌套设计。通过介绍四个具体实例,总结出两种不同的嵌套设计:(1)试验因素之间具有自然属性上的嵌套关系;(2)试验因素对评价指标的影响存在主次关系。通过对实例的解读,揭示嵌套设计具有一个其他多因素设计所缺乏的明显特点,即因素的水平是"纵向连接"而不是"横向组合"的;并从正确合理应用的角度考量,指出了使用嵌套设计时应注意的事项。     

全能干细胞与潜能再生细胞的实验研究进展

全能干细胞(totipotent stem cell,TSC)和潜能再生细胞(potential regenerative cell,PRCs)在实现各组织器官的原位再生,修复或改善损伤组织和器官的结构及功能方面发挥着重要作用,是目前医学领域研究的热点。笔者根据自身研究经验,并通过查阅大量文献资料,综述了全能干细胞与潜能再生细胞的生理作用,旨在为再生医学的后续研究提供一定的方向与思路。     

Comparison of mouse and human retinal morphology and function in albinism: potential implications for therapeutic development

Background

Albinism is a disorder of melanin biosynthesis characterised by abnormal retinal development (foveal hypoplasia) and visual impairment, for which there are no effective treatments. Residual neural plasticity in the infant albino retina has previously been demonstrated. Therapeutic intervention during this developmental period has the potential to rescue visual function. Preclinical studies in murine albinism models are essential to develop novel therapeutics. We aimed to characterise retinal development, morphology, and function in the C57BL/6J-c2J null mouse model of oculocutaneous albinism (OCA), in preparation for future proof-of-concept treatment studies.

微种植体支抗压低上前牙的Typodont实验研究

目的在Typodont模型上,模拟临床应用微种植体支抗压低上前牙的过程,研究不同部位支抗对上前牙压低效果的影响。方法制作上前牙槽骨垂直发育过度的标准Typodont模型42个,随机分为ABC三组,每组14个。A组在中切牙间植入微种植体,B组在中切牙和侧切牙间植入微种植体,C组在侧切牙和尖牙间植入微种植体,应用镍钛螺簧施0．98N（100g）力压低上前牙。应用三维坐标测量仪测量牙齿标记点的三维位置并获得点云数据,Imageware12软件测量牙齿的压低量及唇（颊）倾斜度,并同时拟合牙弓曲线,研究牙弓及[牙合]平面的变化。结果①三组中上前牙均有不同程度的压低（0．9220mm±0．3037mm～5．2354mm±0．9620mm）,中切牙的压低量〉侧切牙〉尖牙,微种植体的位置越靠前,压低效果越明显。②所有牙齿均向前移动,上前牙有不同程度的唇倾,微种植体的位置越靠后,牙齿向前移动越少,唇倾越少。③微种植体的位置越靠后,牙弓及[牙合]平面的变化越小。结论①应用微种植体支抗可以有效地压低上前牙,上磨牙并未伸长。②微种植体的位置越靠后,上前牙的压低量越小,唇倾越少,牙弓变化及[牙合]平面角减少的趋势越小。反之亦然。     

生长抑素逆转三苯氧胺对性激素内环境影响的实验研究

目的:探讨八肽生长抑素奥曲肽(OCT)对三苯氧胺(TAM)所致实验性大鼠性激素内环境失衡的逆转作用.方法:Wistar雌鼠接受致癌剂二甲基苯蒽8周后随机分为对照组和治疗组,治疗组采用OCT,TAM或二者联合治疗14周.应用酶免疫分析法测定血清中雌二醇(E2)、孕酮(P)、泌乳素(PRL)、卵泡刺激素(FSH)和黄体生成素(LH)的水平.结果:血清E2和P含量在TAM组均明显高于对照组(P＜0.05),而OCT TAM组与对照组无明显差异(P＞0.05);PRL含量在OCT组、TAM组和OCT TAM组(1.40ng/ml)均显著低于对照组(2.85ng/ml)(P＜0.05,P＜0.01).结论:OCT在体内可以拮抗TAM对内源性雌激素的影响,从而减少因性激素内环境不平衡所致的副作用.