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61.
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用气相色谱研究抗氧化剂对膜脂肪酸的保护作用   总被引:3,自引:0,他引:3  
卢基贵  王伟  陈文为 《药学学报》1991,26(6):406-410
本文应用气相色谱技术直接测定三种生物膜(人红细胞膜,人血小板膜和鼠肝线粒体膜)多不饱和脂肪酸的含量变化,检测脂质过氧化程度。实验证实几种多羟酚类化合物(儿茶精,阿魏酸钠和没食子酸及其衍生物)不同程度地抑制(OH)诱导的脂质过氧化反应,并呈量效和构效关系。这类抗氧化剂对保护生物膜的结构与功能是有益的。  相似文献   
63.
PURPOSE: (1) To assess prevalence of physical dating aggression and victimization among high school students; (2) to assess prevalence of mutual and exclusive aggression; (3) to determine whether aggression differs across ethnic groups and relationship type; and (4) to ascertain the likelihood of injury and breakup in individuals who reported that they were the recipients of physical aggression. METHODS: Students (N = 2363) from seven multiethnic high schools participated. Because males in high school date females younger than they and the reverse for females, and because males and females may underreport aggression, only within gender comparisons were conducted. RESULTS: More females reported engaging in physical aggression (40%) than reported being victims of aggression (30%). Fewer males reported engaging in physical aggression (24%) than reported being victims of physical aggression (31%). If physical aggression occurred, typically both partners were aggressive. For females, exclusive engagement in physical aggression (perpetration) was reported at higher rates than exclusively being the recipient of physical aggression (victimization) and vice versa for males. Dating aggression was less prevalent among male Asian students than other ethnic groups. Engaged males and females reported the highest rates of physical aggression. Injury was reported by over 25% of males and females who reported being the recipients of physical aggression. CONCLUSIONS: Dating aggression intervention programs should address physical aggression of both males and females. Because approximately 30% of the high school males and females reported being the recipients of physical aggression by their partners, primary prevention efforts should occur before high school.  相似文献   
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本对医学院校学生就全科医生有关问题给于相应的答复,其中还包括自1997年以来由美国全科医学会举办的学生代表大会上所提出的一些问题,例如:什么是全科医生?全科医生的行业范围是什么?全科医生的工作,生活及收入情况如何等等问题。(Am.Fam.Physician1990.60:167-174)。  相似文献   
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Radioimmunoimaging of fresh canine venous thrombi with a murine monoclonal antibody specific for human and dog fibrin has been reported. Successful imaging of canine deep venous thrombi 1, 3, and 5 days old at the time of antibody injection is reported. Images were positive in all dogs, and the uptake of fibrin-specific antibody was equivalent to that of fresh thrombi.  相似文献   
68.
Many people believe that euthanasia and assisted suicide are condoned carte blanche in the Netherlands. Not true. Both are formally forbidden by criminal law and can be administered only when certain procedures and criteria have been followed. Below, a look at the policies and practices regarding euthanasia and assisted suicide in The Netherlands and the role of nurses in this area.  相似文献   
69.
To determine the cause of a positive direct antiglobulin test (DAT), blood banks routinely perform serologic tests on eluates prepared from DAT-positive red cells. Negative eluates traditionally have been suspected to be associated with drug reactions. This report confirms that the most frequent cause of a positive DAT and a nonreactive eluate is hypergammaglobulinemia. The results of 74 patient samples with positive DATs were analyzed retrospectively. Eluates prepared from the red cells of 54 patients (72.9%) reacted; eluates from 20 patients (27.1%) did not react. This latter group had identical serologic and clinical findings, suggesting that they made up a homogeneous group. In particular, the patients had a positive DAT, a negative indirect antiglobulin test, and a negative eluate; an increased serum concentration of IgG; and no evidence of hemolysis. In a subsequent study, DATs were performed prospectively on red cells from 44 consecutive patients with elevated serum IgG levels. The serum IgG concentration was highest in the three patients whose red cells had a positive DAT. The DAT also became positive in two patients treated with high-dose intravenous gammaglobulin (IV IgG). These studies indicate that a negative eluate from red cells with a positive DAT, a common serologic finding, is often caused by hypergammaglobulinemia. The authors postulate that IgG binds nonspecifically to the red cells because of the hypergammaglobulinemia.  相似文献   
70.
目的:终末期肝硬化患者肝病晚期常合并肝肺综合征,伴随低氧血症出现,在肝移植期间进行针对性的通气治疗和管理,对于降低肝移植期的肺部并发症,甚至降低死亡率具有重要的临床意义。文章综合分析低潮气量和低呼期末正压通气对肝移植期间呼吸治疗的作用及其愈后。资料来源:应用计算机检索1970-01/2007-07MEDLINE及万方数据库有关肝移植期间呼吸治疗方面的文献。中文检索词包括"肝移植,肝肺综合征,潮气量,正压呼吸";英文检索词有"liver transplantation,hepato-pulmonary zsyndrome,Tidal ventilation,end-expiratory positive pressure mechanical ventilation"。包括临床研究(不限观察对象的年龄、性别、种族)和基础研究,不限体内或体外研究。资料选择:共收集到1310篇文献,阅读全部文章的文题和大部分文章的摘要,选择肝肺综合征病理改变和通气治疗方面的文献。排除重复性研究和Meta分析类文章。资料提炼:共得到符合纳入条件的文献159篇,排除1141篇。选择其中27篇英文文献及4篇中文文献进行分析。资料综合:①肝肺综合征发病机制错综复杂,术中血流动力学变化及新肝期内毒素、炎性介质、内环境改变等均易发生顽固性低氧血症,甚至出现通透性肺水肿,导致呼吸和心功能衰竭。这些变化是多因素共同作用的结果,在众多发病机制中,肺不张、门肺分流、通气减少或灌流增加均可使通气/灌流比值降低,是导致低氧血症的重要原因。②目前关于肝肺综合征主要是药物处理文献较多,但呼吸治疗报道尚未见到。③根据临床表现术前动脉血氧分压<60mmHg(1mmHg=0.133kPa),动脉二氧化碳分压在正常范围,以及新肝期供肝炎性介质释放,类似于急性呼吸窘迫综合征,因此临床处理均采用呼吸治疗,小潮气量和呼气末正压治疗效果及预后较好。结论:肝肺综合征患者肝移值围手术期应用小潮气量和呼气末正压机械治疗,可降低术后肺部并发症和重症监护时间。  相似文献   
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