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AIMS: To evaluate the relationship between echocardiographic cardiac function and outcome in patients with stable symptomatic angina. METHODS: Baseline echo left ventricular ejection fraction and volume data measured in a central laboratory was available for 7016 patients (92% of the total) participating in the ACTION trial (A Coronary disease Trial Investigating Outcome with Nifedipine GITS). Ejection fraction was also measured by investigators. Evaluation of the different echocardiographic variables was based on adjusted hazard ratios comparing the unfavourable limit of the 90% range of the variable concerned to the favourable limit. RESULTS: The centrally measured ejection fraction was the most powerful predictor of all-cause death (adjusted hazard ratio=2.5), myocardial infarction, any stroke or transient ischaemic attack and overt heart failure (adjusted hazard ratio=4.5). The addition of either end systolic volume or end diastolic volume to ejection fraction did not materially affect the power of prediction. Compared to the central ejection fraction measurement, the investigator-measured ejection fraction was a less powerful predictor for all outcomes considered. CONCLUSION: Routine echocardiography carefully analysed by standardised methods provides useful prognostic information in patients with stable angina, including for total mortality.  相似文献   
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Study Objective . To compare the frequency, severity, and time course of venous irritation after administration of a single intravenous dose of phenytoin with an equimolar dose of fosphenytoin, a water-soluble phenytoin prodrug. Design . Randomized, double-blind, two-period, crossover study. Setting . University hospital clinical research unit. Patients . Twelve healthy volunteers within 15% of ideal body weight and with no clinically significant abnormalities on physical examination, medical history, or laboratory assessment. Interventions . Volunteers randomly received a 30-minute infusion of phenytoin sodium 250 mg (250 mg/5 ml) or an equimolar dose of fosphenytoin 375 mg (375 mg/5 ml). Subjects returned for the crossover treatment 14–21 days later. Measurements and Main Results . Subjects assessed venous irritation (pain, burning, itching), and investigators evaluated phlebitis (erythema, swelling, tenderness), induration, exudation, and cording. Phenytoin was associated with a significantly higher degree of pain at the infusion site in all subjects and a significant degree of phlebitis in eight subjects (p<0.05); cording occurred in six subjects. The time course of phenytoin-induced phlebitis was bimodal. Erythema and tenderness were prominent at the end of the infusion and again at 24 hours. Cording was first noted between 24 hours and 1 week after infusion. In contrast, fosphenytoin was associated with mild pain in two subjects, one incident of phlebitis, and no erythema or cording. Conclusions . Fosphenytoin administration resulted in significantly less venous irritation and phlebitis compared with an equimolar dose of phenytoin. The clinical use of this water-soluble phenytoin prodrug should minimize the frequency and severity of infusion-site reactions and should allow convenient, rapid, intravenous administration of drug, undiluted or admixed with intravenous solutions.  相似文献   
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全层缝合在预防阑尾炎术后切口感染中的应用   总被引:4,自引:0,他引:4  
目的:探讨全层缝合在预防阑尾炎术后切口感染的治疗效果。方法:将皮肤、皮下组织、腹外斜肌腱膜全层褥式缝合(腹膜不予缝合)。结果:56例患者无一例感染,也未发现近期并发症。结论:此方法对预防切口感染有较好疗效,且能缩短手术时间,操作简单,建议值得临床应用。  相似文献   
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267株烧伤感染细菌的调查分析   总被引:1,自引:0,他引:1  
目的:回顾性分析1995年1月至2003年12月间本院烧伤科细菌分布和菌种耐药情况,以指导临床合理用药。方法:收集烧伤病人创面分泌物、血液、痰液及静脉导管末端行普通细菌培养,统计细菌分布情况及常用药物的敏感性。结果:9年来共检出19种267株细菌.其中铜绿假单胞菌和金黄葡萄球菌占83.14%,并有逐渐增加的趋势。铜绿假单胞菌以亚胺培南、头孢哌酮/舒巴坦和多粘菌素B最敏感;氨曲南亦较敏感,且敏感性呈逐渐上升趋势。金黄色葡萄球菌以万古霉素最敏感.呋喃妥因、利福平次之,青霉素类和大部分头孢菌素则高度耐药。结论:目前烧伤感染仍以铜绿假单胞菌和金黄色葡萄球菌为主.防治该两种细菌感染是抗烧伤感染的主要任务。  相似文献   
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Proton relaxation times T1 and T2 of macromolecular solutions, bovine brain tissues, and experimental cat brain edema tissues were studied as a function of water concentration, protein concentration, and temperature. A linear relation was found between the inverse of the weight fraction of tissue water and the spin-lattice relaxation rate, R1, based on a fast proton exchange model for relaxation. This correlation was also found for the spin-spin relaxation rate, R2, of gray matter samples and macromolecular solutions at low concentrations. Concentrated solutions of protein-water samples showed an enhanced relaxation due to viscosity effects. The T2 of white matter was considerably lengthened with elevated water concentration, but showed no straightforward relation with the total tissue water content. The relaxation times of all samples increased with temperature, supporting the assumption of fast proton exchange in the model for relaxation. This was not found for white matter, in which T2 decreased with increasing temperature, which indicated that intermediate or even slow exchange was present. The relation found between relaxation times and tissue water content can be used to predict the amount of and/or increase in tissue water due to water-elevating processes such as edema.  相似文献   
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