L-丙酰肉碱对再灌注心肌损伤的保护及体外抗自由基作用

目的:观察L－丙酰肉碱对缺血再灌注心肌的保护作用，并探讨其机理。方法：采用大鼠在体心脏冠状动脉前降支阻断5min造成缺血再灌注模型，持续心电监护，观察心律失常与心功能指标；应用电子顺磁共振观察L－丙酰肉碱对Fenton体系及二甲基亚砜（DMSO）碱性有氧体系产生自由基的作用。结果：L－丙酰肉碱静脉给药明显减少再灌注时室性心动过速、室性纤维颤动的发生（P＜0．05），促进再灌注后左室收缩压、左室压最大上升速率、左室压最大下降速率、心力环面积的恢复，与对照组相比，各参数均明显增高（P＜0．05）；静脉注射L－丙酰肉碱100mmol／L时促进Fenton体系OH的产生，而500mmol／L时产生明显抑制作用，L－丙酰肉碱明显抑制DMSO碱性有氧体系OS的产生。结论：L－丙酰肉碱明显减少再灌注心律失常的发生，促进再灌注后心功能的恢复。推测它对自由基的作用可能是再灌注损伤保护机理之一。     

Immunochemical characterization of multiple forms of cytochrome P-450 in rabbit nasal microsomes and evidence for tissue-specific expression of P-450s NMa and NMb

Two unique forms of cytochrome P-450 (P-450), designated NMa and NMb, were recently isolated in this laboratory from nasal microsomes of rabbits. In the present study, polyclonal antibodies to the purified nasal cytochromes were prepared. Immunochemical analysis with specific rabbit anti-NMa and sheep anti-NMb antibodies indicated that P-450 isozymes identical to or having a high structural homology with NMa are present in both olfactory and respiratory mucosa, as well as in liver, but NMb was detected only in the olfactory mucosa. Neither form was detected in other tissues examined, including brain, esophageal mucosa, heart, intestinal mucosa, kidney, and lung. The specific occurrence of NMb in the olfactory mucosa was further substantiated by the detection and specific inhibition by anti-NMb of the formation of unique NMb-dependent metabolites of testosterone in olfactory microsomes but not in microsomes from liver or respiratory mucosa. Similar experiments with antibodies to previously purified rabbit hepatic P-450 isozymes indicated that not all of the hepatic cytochromes are expressed in the nasal tissues. Thus, P-450 isozymes structurally homologous to hepatic forms 2, 3a, and 4, but not 3b and 6, were found in the olfactory mucosa. On the other hand, only form 2 was detected in the respiratory mucosa. Immunoquantitation experiments revealed that NMa and NMb are the major P-450 forms in olfactory microsomes, whereas NMa and P-450 form 2 (or its homolog) constitute the major portion of the respiratory nasal microsomal P-450. The level of NMa in the liver is relatively low, accounting for less than 3% of total microsomal P-450 in this tissue. In addition, evidence is provided that NMa is the major catalyst in the dealkylation of two nasal carcinogens, hexamethylphosphoramide and phenacetin, in both olfactory and respiratory nasal microsomes.     

大肠肿瘤组织中EB病毒的原位杂交检测

目的：探讨EB病毒感染与人大肠癌发生的关系。方法：用原位分子杂交法对130例人大肠癌标本中EB病毒小分子RNA片段进行检测。结果：130例标本中有6例（4.48％）癌组织呈阳性反应，其中4例为男性，4例有明显淋巴细胞浸润。结论：EB病毒感染可能与我国部分大肠腺癌的发生有关，肿瘤细胞间质中大量淋巴细胞浸润可能是EB病毒感染的重要病理学特征。     

幽门螺杆菌ureB基因表达产物的反应原性

目的：克隆幽门螺杆菌ureB基因，并进行表达，验证表物的反应原性。方法：应用PCR技术从技术临床分离株中扩增出ureB基因，克隆入载体pGEM-7zf( ）进行测序，进一步转到友大肠杆菌表达载体pBV220进行诱导表达，以Western blot实验验证重组蛋白的反应原性。结果：测序后经同源性比较，证实扩增后得到的片断确为ureB基因，并原核表达出可被抗Hp抗体识别的非融合重组蛋白。结论：获得了有反应原性的重组ureB蛋白。     

大鼠内毒素血症时外周血及肺泡内中性粒细胞死亡方式及呼吸爆发

本研究观察大鼠内毒素血症时肺组织中及外周血多形核中性粒细胞（PMN）凋亡，坏死及功能改变的差异。采用Wistar大鼠20只。腹腔注射LPS（O55B5，5mg/kg)造成内毒素血症，给予LPS后2，4，8，12小时（每组5只动物）取血及支气管肺泡灌洗，密度梯度法分离PMN，用流式细胞仪测定凋亡和坏死比例以及呼吸爆发功能的改变，同时采用5只大鼠作为正常对照。结果显示，内毒素血症时外周血和支气管肺泡灌洗液中PMN凋亡细胞比例相似。但与对照相比，外周血PMN坏死比例明显增加，呼吸爆发能力明显受抑，而支气管肺泡灌洗液PMN坏死比例显减少，呼吸爆发能力显增强。结论：在内毒素血症时，扣押于肺组织中的PMN在凋亡和坏死上表现出与比例显减少，呼吸爆发能力显增强，结论：在内毒素血症时，扣押于肺组织中的PMN在凋亡和坏死上表现出与外周血PMN不同的改变，其结果是组织中PMN存活增加，并持续处于活化状态，这与PMN造成组织损伤有关。