Nebivolol induces endothelium-dependent relaxations of canine coronary arteries.

Nebivolol is a new beta 1-antagonist that acutely reduces arterial blood pressure without depressing cardiac function. The present study was designed to determine the effect of nebivolol on coronary arteries. Rings of canine left anterior descending coronary (LAD) artery with or without endothelium were suspended in organ chambers and the isometric tension was recorded. In some experiments, the transmembrane potential of the smooth muscle cells was recorded by electrophysiological methods. During contractions to prostaglandin F2 alpha, nebivolol induced concentration-dependent relaxations of the coronary arteries. The enantiomer, l-nebivolol, also induced comparable relaxations; however, d-nebivolol induced smaller relaxations. The relaxations induced by nebivolol and its enantiomer were significantly larger in tissues with than in those without endothelium. The differences between tissues with and without endothelium were abolished by nitro-L-arginine (3 x 10(-5) M) or methylene blue (10(-5) M). The nebivolol-induced relaxations were not affected by indomethacin (10(-5) M), phentolamine (5 x 10(-6) M), propranolol (5 x 10(-6) M), or methysergide (3 x 10(-6) M). Nebivolol at a subthreshold concentration for inducing relaxation (3 x 10(-7) M) did not significantly affect endothelium-dependent relaxations to acetylcholine but potentiated ADP-induced endothelium-dependent relaxations. The potentiation is stereoselective for l-nebivolol. Nebivolol induced a small hyperpolarization of the coronary smooth muscle with endothelium (1 mV).(ABSTRACT TRUNCATED AT 250 WORDS)     

联合雾化吸入对老年支气管哮喘急性发作的疗效观察及护理

支气管哮喘是一种由多种细胞及细胞因子参与的慢性炎症性疾病。气道慢性炎症导致气道高反应,从而产生反复发作的喘息、胸闷、呼吸困难、咳嗽等相关症状,尤其多发于夜间及凌晨。我科自2005年6月开始采用特布他林、异丙托溴胺、布地奈德联合雾化吸入治疗老年哮喘急性发作取得满意疗效。现报告如下。1一般资料1.1对象我科2005年6月—2007年5月共收治老年支气管哮喘急性发作病人78例,年龄65岁~95岁(73.0岁±6.0岁),均符合诊断标准[1]。随机分为两组,对照组38例:男30例,女8例;治疗组40例:男35例,女5例。两组年龄、性别比较,差异无统计学意义(P>0…     

中国中原地区33555名妇女妇科疾病发生情况与五种因素关系的调查报告

自１９９２年３月至１９９４年５月，对中原地区４个省２０多个县（市）近２００个单位３３５５５名２０～７５岁的已婚妇女，进行妇科疾病发生情况与年龄、职业、文化、月经、孕产等五种因素关系的调查分析。在３３５５５名妇女中，患病者２２３７０人，总患病率为６６．６７％，查出妇科疾病４２种，计７６９７４例次。结果证明：以２５～３５岁年龄组发病率最高，其中以内生殖器炎症为主；职业以经商者发病率高，特别是性病患者高于其他职业者二倍以上；文化程度以小学、初中者发病率高，尤其宫颈炎更明显；月经情况：随着经前期紧张综合征的加重，更年期综合征发病率增高；孕产次数越多，患病率越高。本次调查未发现宫颈癌，进一步证明我国对妇女保健工作的关心和重视。     

Evidence for the interaction between antacid and gastric mucosa using an "artificial stomach" model including gastric mucosa.

In light of evidence that certain aluminum-based antacids adhere to the gastric mucosa, we modified our previously described "artificial stomach" (AS) model by including a piece of hog stomach and compared the antacid activity of six aluminum-containing antacid products in the model with and without gastric mucosa. The activity of three of these, Maalox, Riopan and Supralox, was not significantly different in the two systems. In contrast, the activity of the other three, Aludrox, Phosphalugel and Simeco, was significantly greater with mucosa. Antacid activity of one product from each set (Supralox, Phosphalugel) was evaluated in two in vivo methods in human volunteers. For both antacids, results in vivo were similar to those obtained with the AS-containing mucosa. Without mucosa, in vivo and in vitro results were dissimilar for Phosphalugel, thus validating the modified AS. The difference between the two sets of antacids can be explained by 1) the fact that the Al:Mg ratio in the set affected by mucosa is greater than that of unaffected antacids, and 2) a weaker antacid load than in unaffected Supralox. We suggest that in an acid milieu, aluminum ions in antacids like Aludrox, Phosphalugel and Simeco are bound to sialic acid residues in mucus glycoproteins, thus retarding the transit of these antacids through both the AS and the real stomach and prolonging their activity in both situations. When the Al:Mg ratio is low or when the amount of antacid salts is large, aluminum ions tend to be buried in complexes, giving them less chance to interact with gastric mucus, so they transit the stomach more quickly.     

Molecular genetic characterization of XRCC4 function

XRCC4 is a generally expressed protein of 334 amino acids that is involved in the repair of DNA double-strand breaks and in V(D)J recombination, but its function is unknown. In this study, we have used a mutational approach and the yeast two-hybrid method to perform an initial characterization of this protein. We show that the XRCC4 protein is located in the nucleus. We also demonstrate that several potential phosphorylation sites are not required for XRCC4 function in a transient V(D)J recombination assay. In addition, we show that XRCC4 forms a homodimer in vivo with the homodimerization domain being located within amino acids 115-204. Finally, we define a core domain of XRCC4 that functions in V(D)J recombination and comprises amino acids 18-204. Potential functions of XRCC4 are discussed.      

扫描电镜图像处理系统及其在细胞超微结构定量计算中的应用

本文介绍一种具有较高性能价格比的生物医学电镜图像处理系统,该系统以IBM PC/XT,AT或386计算机为主机,图像接口板直接插入机内扩展槽。应用软件可对生物医学图像作图像处理和定量计算。作者通过对人膈腹膜超微结构进行定量分析,为腹水的治疗和腹膜透析(CAPD)等临床医学研究,提供了形态学定量资料。     

乙醇对人绒毛孕酮分泌的影响

本工作利用灌流技术观察了四种不同浓度的乙醇(0.5％、1％、2.5％、5％)对妊娠早期人工流产新鲜胎盘绒毛分泌孕酮的影响。结果表明,乙醇具有促进孕酮分泌的作用,并存在剂量依赖的关系。提示乙醇可能破坏胎盘激素内分泌的平衡,从而影响胎儿的正常生长与发育。     

Prevalence of neutralizing antibodies to adenoviral serotypes 5 and 35 in the adult populations of The Gambia, South Africa, and the United States

One of the major limitations of the use of adenoviruses as gene therapy vectors is the existence of preformed immunity in various populations. Recent studies have linked failure of adenoviral gene therapy trials to the presence of antiadenoviral neutralizing antibodies (NAb). Understanding the distribution and specificity of such antibodies will assist in the design of successful recombinant adenoviral gene therapies and vaccines. To assess the prevalence of NAb to adenovirus serotypes 5 and 35 (Ad5 and Ad35), we analyzed serum samples from adult immunocompetent individuals living in The Gambia, South Africa, and the United States by using a neutralization assay. Serum samples were incubated with A549 lung carcinoma cells and adenoviruses encoding enhanced green or yellow fluorescent proteins; results were analyzed by fluorescence microscopy and flow cytometry. Using this technique, we found a high prevalence of NAb against Ad5 in Gambian, South African, and U.S. subjects at both low and high titers. Conversely, all subjects displayed a low prevalence of NAb to Ad35; when present, anti-Ad35 NAb were seen at low titers. Because of the ability of adenoviruses to elicit systemic and mucosal immune responses, Ad35 with its low NAb prevalence appears to be an attractive candidate vector for gene therapy applications.