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51.
Summary The release of endogenous catecholamines in aorto-coronary bypass graft patients receiving either 0.5 mg/kg enoximone (n=10), 4.0 mg/kg theophylline (n=10) or saline solution (control,n=10) has been studied, as well as certain haemodynamic parameters. Adrenaline (A) and noradrenaline (NA) concentrations were not significantly changed by the administration of enoximone. Theophylline caused a small increase in NA (+ 40% in the 1st min) and a marked increase in A (approximately + 7000% in the 1st min), which still remained elevated at the end of the investigation period (+ 220% in the 30th min). The major haemodynamic effects of enoximone were a significant increase in cardiac index (CI; + 35%) and a decrease in pulmonary capillary wedge pressure (PCWP; −27%), pulmonary artery pressure (PAP; −21%), RVEDV and RVESV, while the heart rate (HR) remained almost unchanged. The dominant haemodynamic effects of theophylline were an increase in HR (+ 26%; arrhythmia in 3 patients), PAP (+ 22%), and RVEDV (+ 19%), while REVESV (+ 26%), MAP (−16%), CI (−14%), and RVEF (−15%) fell significantly. It is concluded that the haemodynamic actions of enoximone are not mediated by catecholamine release, whereas the adverse cardiovascular effects of theophylline might partly be explained by the significant increase in plasma adrenaline.  相似文献   
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A prospective survey was performed in 17 nuclear medicine departments during 1996 in an attempt to provide reliable data on the prevalence of adverse reactions to radiopharmaceuticals. All adverse events following radiopharmaceutical administration were recorded, irrespective of the severity or likelihood of causality, and subsequently analysed using an algorithm developed by Silberstein et al., designed to establish a cause-effect relationship. A prevalence of 11 events per 105 administrations was obtained (95% confidence limits 3.3–19.2). No serious of life-threatening events were reported. This rate is slightly higher than that obtained in a larger scale study in the United States (2.3 events per 105 administrations, 95% confidence limits 1.2–3.4). The difference may be due to the decision to include or exclude vasovagal events from the analysis, the way in which the algorithm was used and the comparative size and time scale of the two studies. The prevalence of adverse reactions is approximately 1000-fold than less that occurring with iodinated contrast media and drugs.  相似文献   
54.
This is a report on a comparative study of the reactivity of TRUE Test and Finn Chamber patch test techniques. 413 patients attending a contact dermatitis clinic in Singapore were simultaneously patch tested with panels 1 and 2 of the TRUE Test standard series and with corresponding allergens (Hermal, Hamburg) using Finn Chambers. The left/right application of the TRUE Test and Finn Chambers was randomized. The concordance of positive patch test reactions to the 2 test techniques was studied. The number of patient with positive reactions was 38% and 42% for TRUE Test and Finn Chamber techniques, respectively (n.s.). The overall concordance of positive patch test reactions was 64% (209/328). 13% (42/328) of positive reactions appeared on TRUE Test only and 24% (77/328) on Finn Chamber only. When only relevant positive reactions were considered, the concordance rate was 67%; 11.6% of positive reactions appeared on TRUE Test only and 21% on Finn Chamber only. Positive reactions to p-phenylenediamine (PPD) and neomycin were more frequent with the Finn Chamber technique than with TRUE Test, i.e., false negative reactions to PPD and neomycin were more likely to occur with TRUE Test. It appeared that the TRUE Test and Finn Chamber techniques were comparable when used for patch testing. However false negative and false positive patch test reactions can occur when using either technique.  相似文献   
55.
The relationship of skin reactivity and serum immunoglobulin E (IgE) levels to the prevalence of chronic respiratory symptoms and to ventilatory capacity is examined in workers exposed to different organic aerosols. The results from group of control workers similarly tested are also presented. Workers exposed to occupational allergens had positive skin tests more frequently than did controls, except for soy bean workers. Workers with positive skin tests to occupational allergens had a higher prevalence of almost all symptoms than those with negative skin tests although the differences did not always reach statistical significance. Workers with positive skin reactions in general had significantly higher serum IgE levels than did workers with negative skin reactions. There were across-shift reductions of ventilatory capacity in all groups of exposed workers, varying for forced vital capacity from 1.7% to 13.3%, for forced expiratory volume from 0.4%–21.9%, for maximum flow rates at 50% from 1.5% to 16.1% and for maximum flow rates at the last 25% of control vital capacity from 0% to 24.9%. There was, however, no correlation between acute and chronic lung function changes and skin reactivity or IgE values. Our data suggest that although exposure to organic aerosols may be associated with frequent immunologic reactions, these findings do not predict objective respiratory impairment.The research was supported in part by grant no. JBP 733 from the National Institutes of Health, Bethesda, Md., USA, and by grant no. RO1 OHO-2593-04 from the National Institutes of Occupational Safety and Health, Centers for Disease Control, Atlanta, Ga., USA  相似文献   
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57.
医疗器械不良事件监测-现状与展望   总被引:23,自引:0,他引:23  
介绍医疗器械不良事件的基本概念,论述美国、欧盟、日本和有关国际组织关于医疗器械不良事件监测的管理规定,并回顾和展望我国在该领域的相关工作.  相似文献   
58.
For solid-phase peptide synthesis, 2, 4-dimethoxy-4′ -hydroxybenzhydrol linker was prepared via lithium borohydride reduction of 2, 4-dimethoxy-4′-hydroxybenzophenone. The potassium salt of the linker was coupled to chloromethylpolystyrene. This method proved to be better than use of the cesium salt. This new synthesis gave a polymer with appropriate structure and a good degree of substitution.  相似文献   
59.
Substance P and human nasal mucociliary activity   总被引:2,自引:0,他引:2  
Summary Substance P (SP), a potent inflammatory agent, has been found in sensory nerve fibres in the nasal mucosa in several experimental animals as well as in man. It may participate in the inflammatory response as part of the mucosal defence against foreign materials. In experimental animals SP has been found to increase mucociliary in airway mucosa. The present study was performed in order to find out the relationship between topically applied SP and nasal mucociliary function in humans. Thirteen healthy volunteers were challenged with 65 µg SP or placebo in a randomized cross over fashion and mucociliary transport time was determined each time using the saccharine dye test. The dose of SP was chosen after an open dose-response study. No statistically significant change in the mucociliary transport time was found after challenge with SP as compared to placebo. The possible reasons for this are discussed.  相似文献   
60.
目的:使输液疗法中药物不良反应降到最低限度,使患者获得安全、有效的治疗,同时,也是对有限药物资源的维护。方法:对用四类抗感染药物出现不良反应91例患者行减慢输液速度、平卧、松解领扣、按合谷穴、心理护理、保暖、进饮食等处置。结果:91例药物不良反应,有89例顺利完成输液治疗,2例无效,更换药物。结论:有责任感,加强观察护理及时发现患者反应前驱症状,迅速采取有效措施,会取得满意效果。  相似文献   
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