Abeta-degrading endopeptidase,neprilysin, in mouse brain: synaptic and axonal localization inversely correlating with Abeta pathology

Metabolism of amyloid-beta peptide (Abeta) is closely associated with the pathology and etiology of Alzheimer's disease (AD). Since neprilysin is the only rate-limiting catabolic peptidase proven by reverse genetics to participate in Abeta metabolism in vivo, we performed detailed immunohistochemical analysis of neprilysin in mouse brain using neprilysin-deficient mice as a negative control. The aim was to assess, at both the cellular and subcellular levels, where Abeta undergoes neprilysin-dependent degradation in the brain and how neprilysin localization relates to Abeta pathology in amyloid precursor protein (APP)-transgenic mice. In hippocampus, neprilysin was present in the stratum pyramidale and stratum lacunosum-moleculare of the CA1-3 fields and the molecular layer of the dentate gyrus. Confocal double immunofluorescence analyses revealed the subcellular localization of neprilysin along axons and at synapses. This observation suggests that after synthesis in the soma, neprilysin, a type II membrane-associated protein, is axonally transported to the terminals, where Abeta degradation is likely to take place. Among various cell types, GABAergic and metabotropic glutamate 2/3 receptor-positive neurons but not catecholaminergic or cholinergic neurons, expressed neprilysin in hippocampus and neocortex, implying the presence of a cell type-specific mechanism that regulates neprilysin gene expression. As expected, Abeta deposition correlated inversely with neprilysin expression in TgCRND8 APP-transgenic mice. These observations not only support the notion that neprilysin functions as a major Abeta-degrading enzyme in the brain but also suggest that down-regulation of neprilysin activity, which may be caused by aging, is likely to elevate local concentrations of Abeta at and around neuronal synapses.     

大鼠咽肌前运动神经元的跨突触定位

支配咽肌的运动神经元位于疑核，控制凝核的前运动神经元位于孤束核。孤束核中的前运动神经元在控制吞咽运动中起着重要作用。但支配咽肌的前运动神经元位于孤束核的什么部位还不清楚。文内用假狂犬病毒研究字大鼠咽肌前运动神经元在孤束核中的定位。     

自血光量子疗法治疗病毒性肝炎72例疗效观察

1993年9月以来,用自血光量子治疗各型病毒性肝炎72例,结果所有患者症状均明显好转或消失,SB异常者恢复正常和有效分别占66.7％和90.2％,ALT异常者恢复正常和有效分别为77.4％和100％,血清白蛋白平均上升4.2g/L,球蛋白下降4.6g/L,三项凝血功能(PT、HPT、KPTT)测定结果表明量子血疗不会引起或加重肝炎患者的凝血障碍。61例乙型肝炎患者HBeAg和HBsAg的阴转率分别达59.3％和15％。     

腕关节关节囊内韧带的解剖观察及其创伤学意义

本文描绘了腕关节关节囊内韧带的解剖,其中首次描述了中腕关节的韧带连结,即大、小多角骨,头状骨至舟状骨的韧带和钩骨至三角骨的韧带.本文还论述了与这些韧带连结方式密切相关的腕骨生理运动特点及维持腕关节稳定性的因素.文章还讨论了与腕关节关节囊内韧带有关的腕部创伤学特点.     

ABO血型基因分型及应用

目的 :研究ABO血型基因分型的意义。方法 :采用聚合酶链反应 序列特异性引物 (PCR SSP)基因定型方法对ABO血型基因定型并观察其基因多态性分布特征和疑难血型检定。结果 :对已知ABO基因的DNA标本进行基因定型 ,证实文中的ABO基因定型方法可靠 ;对 10 4例健康、无血源关系的汉族个体ABO血型基因定型 ,结果与血清学所定表型完全符合 ;并用ABO基因分型技术解决临床输血前血型鉴定、产前胎儿血型鉴定、亲权试验及血清学亚型的正确性验证。结论 :ABO血型基因分型技术可以正确判定ABO血型疑难样本     

心电信号预处理与心电信号分析

本文介绍了在一种便携式心电监护仪器中是如何对心电数据进行预处理和智能分析的．为了适应便携式仪器的特征，我们在心电信号预处理中采用了FFT滤波和滑动平均滤波的方法去除各种干扰并使图像得以平滑，同时采用了差分阈值法提取特征点，考虑到监护仪器的实用性，在心电信号分析阶段，我们采用了分析特征间期异常情况的方法来替代对病症的智能诊断功能。     

Serum levels of total IgE in non-allergic children

The purpose of this study was to establish the range of total serum IgE in a healthy population lacking personal and family history of allergy, as well as the influence of genetic factors (family history of allergy), environmental factors (degree of air pollution), age, and sex on the serum IgE levels. Using a commercial enzyme immunoassay (Phadezym IgE Prist) the mean serum level of IgE was determined in 363 non-atopic children from 0 to 12 years of age. The geometric mean of serum IgE increased according to age, indicating a positive correlation between both. Higher mean values of serum IgE were found for children with a family history of allergy, than for children without (27.82 and 14.49 U/ml respectively). The percentage of variation due to age was about 94.5% in children with no family history of allergy. The mean value of serum IgE increased with the degree of air pollution in the living area (15.49 U/ml in non-polluted areas, 20.78 U/ml in very polluted areas). However, the influence of air pollution was smaller than the influence of family history on the mean values of serum IgE. The mean value of serum IgE was not modified by sex.     

胡萝卜籽挥发油的抗生育作用

胡萝卜籽挥发油对小鼠有抗着床,抗早、中和晚期妊娠作用。对大鼠也有抗着床作用。挥发油中的萜类碳氢化合物部位,对小鼠皮下注射抗早期妊娠的ED_(50)为2.9ml/kg,甲地孕酮和hCG能明显逆转其作用;对假孕小鼠蜕膜瘤有抑制作用,此作用不能被甲地孕酮拮抗,皮下注射于早孕大鼠24、48小时后血浆孕酮浓度明显下降。以上提示其抗早孕作用机制可能与抑制孕酮合成和蜕膜反应有关。此外,挥发油碳氢部分无雌激素和抗雌激素活性,低浓度时对早孕大鼠离体子宫的收缩活动没有影响,高浓度则表现抑制作用。     

山紫菀与紫菀镇咳祛痰作用的实验研究

本实验对山紫菀(蹄叶橐吾Ligularia fischeri Turcz.)作了镇咳、祛痰作用的研究,并与紫菀(Aster tataricus L.)在同等条件下进行了比较,它们的浓缩水煎剂均有明显的祛痰作用,而无明显的镇咳作用,二者之间无显著性差异。它们的挥发油乳剂及水煎剂也均未表现出明显的镇咳作用。紫菀挥发油毒性大于山紫菀。