大鼠回肠肌间神经丛内一种特殊类型的神经元

实验用乙酰胆碱酯酶和一氧化氮合成酶组织化学方法,对１０只大鼠回肠肌间神经丛进行研究。发现肌间神经丛的一些神经元,沿毛细血管周围分布,有的甚至与毛细血管壁相紧贴,将其称为毛细血管周神经元。这些神经元胞体呈梭形,梨形或多角形,均呈一氧化氮合成酶阳性反应,而乙酰胆碱酯酶反应阴性。这种神经元类似于中枢神经系统的接触脑脊液神经元,它们可能具有神经分泌或感受血液中某些化学成分成分变化之功能。     

医务人员工作倦怠--一个不容忽视的问题

介绍工作倦怠的基本概念,以及医务人员工作倦怠的现状,简要分析倦怠产生的原因和倦怠对医疗服务的不良影响,最后提出几点干预措施来预防和控制工作倦怠,以提高医务人员的个人健康和医疗服务质量.     

红外热成像用于慢性足底筋膜炎诊断的临床研究

目的:观察慢性足底筋膜炎患者的足跟皮肤温度变化特点并探讨红外热成像检查是否可作为评估患者疼痛与功能状态的客观指标。方法:选取32例临床最终诊断为单侧慢性足底筋膜炎患者,依据患者有无症状分为有症状侧和无症状侧,将足跟部皮肤依据象限划分为5个感兴趣区(ROI),使用红外热像仪系统对患者双侧足底及手指进行红外热图像观察,并记录每个患者的足跟部ROI平均温度、视觉模拟评分(VAS)和足踝残疾指数(FADI)。分别比较有症状侧和无症状侧的足跟部5个ROI温度的差异,分析有症状侧5个ROI温度与VAS,FADI之间的关系,评估有症状侧5个ROI温度与疼痛、功能评分的相关性。结果:有症状侧和无症状侧的5个ROI的温度差异均有统计学意义(P<0.05),有症状侧足底各ROI的平均温度与VAS之间无相关性(P>0.05),有症状侧足跟部5个ROI的平均温度均与FADI之间有相关性(r=-0.55)。结论:慢性足底筋膜炎患者足跟部皮肤温度升高,且有症状侧足跟温度与临床评分之间具有相关性,红外热成像检查可以作为评价慢性足底筋膜炎患者与疼痛相关的功能指标。     

2，4-二硝基氯苯诱导的特应性皮炎样小鼠模型的皮肤菌群特征研究

目的:探讨不同浓度2,4-二硝基氯苯（DNCB）诱导的特应性皮炎（AD）样小鼠模型特点及皮肤菌群改变。方法:将30只雄性、无特定病原级BALB/c小鼠按随机数字表法等分为3组：阴性对照组小鼠背部涂抹200 μl丙酮和橄榄油（体积比为3∶1）每周2次,连续6周;高、低浓度DNCB组小鼠于第1周的第1、3天均涂抹1% DN...     

Experiment in infecting the green monkey Cercopithecus aethiops with a leukocyte virus isolated in hepatitis A

The virus isolated in hepatitis A had been previously shown to passage in primary phytohemagglutinin-stimulated leukocyte cultures. The virus designated as leukocyte hepatitis virus (LHV) causes chromosome aberrations in the infected cultures. Some physico-chemical properties of LHV and its capacity for reproduction in other cell systems were studied. In serological surveys of patients and in studies of cellular immunity reactions of them LHV was found in cases of hepatitis. The possibility of producing a laboratory model of hepatitis in green monkeys, morphological reaction to inoculation with LHV, as well as the presence of specific antigen in the inoculated animals by immunofluorescence test using rabbit immune serum to LHV and FITC-labelled gamma globulins from hepatitis A convalescents were investigated. LHV antigen was found in the lymph nodes, spleen and liver. Active morphological reaction of lymph nodes and spleen was observed 30 days after inoculation of monkeys. The results indicate that in green monkeys LHV possesses marked reticulotropic properties without producing clinical hepatitis, therefore African grivet monkeys (Cercopithecus aethiops), apparently, cannot be used as experimental models for LHV studies in vivo.     

Anchoring dental implant in tissue-engineered bone using composite scaffold: a preliminary study in nude mouse model.

PURPOSE: The purpose of this study was to fabricate a tissue-engineered bone graft anchoring dental implant with bone marrow stromal cell (bMSC) seeded coral-implant composite scaffold. MATERIALS AND METHODS: Titanium dental implants (3 mm in diameter) were inserted into the cylinder coral scaffolds (5 mm in diameter and 1 mm in wall thickness). bMSCs were isolated from iliac bone marrow of adult New Zealand White rabbits, induced by dexamethasone and seeded into the composite scaffold at the density of 2 x 10 8 /mL in 200 muL medium. Nine cell coral-implant complexes were incubated in vitro for 5 days. One complex was processed for scanning electronic microscopy. The other 8 complexes, together with 4 coral scaffold without cell acting as control, were implanted subcutaneously into nude mice back. At 1 and 2 months after implantation, 4 specimens from the experiment group and 2 specimens from the control group were harvested respectively. New bone restoration and new bone integration with dental implant were evaluated by gross inspection, manual handling test, radiographic examination, and histologic observation. RESULTS: Specimens harvested at 2 months after implantation were red and similar to native bone. Manual handling test showed that dental implants were fixed in the newly formed bone. Radiographic examination showed that most of the coral scaffold had been absorbed. Bone density x-ray shadow could be observed around the dental implant. Histologic examination showed that large amount of new bone formed around the dental implants and integrated well with the implants in some area. In the control group no bone formation was observed both macroscopically and microscopically. CONCLUSION: The results of the study suggested that the tissue-engineered bone of bMSCs seeded natural coral-implant composite scaffold is promising for dental implant anchoring, which has positive implication for clinical jaw reconstruction.     

Familial Alzheimer disease-linked mutations specifically disrupt Ca2+ leak function of presenilin 1

Mutations in presenilins are responsible for approximately 40% of all early-onset familial Alzheimer disease (FAD) cases in which a genetic cause has been identified. In addition, a number of mutations in presenilin-1 (PS1) have been suggested to be associated with the occurrence of frontal temporal dementia (FTD). Presenilins are highly conserved transmembrane proteins that support cleavage of the amyloid precursor protein by gamma-secretase. Recently, we discovered that presenilins also function as passive ER Ca(2+) leak channels. Here we used planar lipid bilayer reconstitution assays and Ca(2+) imaging experiments with presenilin-null mouse embryonic fibroblasts to analyze ER Ca(2+) leak function of 6 FAD-linked PS1 mutants and 3 known FTD-associated PS1 mutants. We discovered that L166P, A246E, E273A, G384A, and P436Q FAD mutations in PS1 abolished ER Ca(2+) leak function of PS1. In contrast, A79V FAD mutation or FTD-associated mutations (L113P, G183V, and Rins352) did not appear to affect ER Ca(2+) leak function of PS1 in our experiments. We validated our findings in Ca(2+) imaging experiments with primary fibroblasts obtained from an FAD patient possessing mutant PS1-A246E. Our results indicate that many FAD mutations in presenilins are loss-of-function mutations affecting ER Ca(2+) leak activity. In contrast, none of the FTD-associated mutations affected ER Ca(2+) leak function of PS1, indicating that the observed effects are disease specific. Our observations are consistent with the potential role of disturbed Ca(2+) homeostasis in Alzheimer disease pathogenesis.     

饮酒对长期酗酒者MCA血流灌注影响的TCCD对照研究

目的　探讨饮酒对长期酗酒者脑血流灌注影响的规律。方法　应用经颅彩色多普勒 (TCCD) ,对 76例酗酒者 (实验组 )及 5 2例非酗酒者 (对照组 )分别在饮酒前、饮酒后 30 min、1h、 2 h测定脑血流动力学参数 :收缩期峰值流速 (Vp)、舒张末期流速 (Vd)、平均血流速度 (Vm)、搏动指数 (PI) ,并观察频谱形态。采用同一品牌和批号的市售白酒 ,饮酒量按纯酒精折算 (0 .6 5 g/kg) ,实验于晚餐前 2 h开始 ,2 0 min内饮入。结果　 (1)酗酒者饮酒前双侧大脑中动脉 (MCA)基础血流速度 (Vp、 Vd及 Vm)均较正常减低、搏动指数 (PI)增大(P分别 <0 .0 1或 <0 .0 5 ) ,以平均血流速度 (Vm )减低最明显。血流频谱形态圆钝 ,S1 、 S2 峰融合 ,S2 >S1 。酗酒者饮酒后 30 min血流动力学参数较饮酒前变化不明显 ,1h后血流速度较饮酒前增高 (P<0 .0 1或 <0 .0 5 ) ,饮酒后 2 h各血流动力学参数基本恢复到饮酒前状态 ;(2 )非酗酒者饮酒后 30 min脑血流速度明显增高 ,1h后达到高峰 ,2 h后基本恢复到饮酒前状态 ;饮酒后脑动脉血流频谱 S1 峰较饮酒前尖耸。结论　本研究显示 :是否长期酗酒脑血流灌注情况有所不同、对急性酒精干预的反应不同 ;揭示了长期酗酒者对脑血流灌注的损害 ,对慢性酒精中毒、酒精性脑病的早期诊断和防治提供一