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Premedication and high-dose fentanyl anesthesia for myocardial revascularization: a comparison of lorazepam versus morphine-scopolamine 总被引:2,自引:0,他引:2
Using a randomized double-blind placebo-controlled experimental protocol, the authors compared two premedication regimens in 42 patients undergoing elective myocardial revascularization. Group L patients (n = 23) received lorazepam 0.06 mg/kg po 90 min preoperatively, while group M patients (n = 19) received morphine 0.1 mg/kg im, plus scopolamine 0.006 mg/kg im 60 min preoperatively. Anesthesia was induced with fentanyl 100 micrograms/kg and atracurium 0.50 mg/kg administered over 10 min. The treatment groups did not differ significantly with respect to the degree of sedation or anxiolysis achieved, or the rapidity of induction with fentanyl. Premedication significantly influenced the hemodynamic response to anesthetic induction. Hemodynamics were stable post-induction in group M, but cardiovascular depression was noted in group L. Control heart rate (HR) was lower in group L. The HR, arterial pressure, and cardiac index were significantly lower, following both induction and intubation, in group L. Following sternotomy hemodynamics were identical in both groups. Serum fentanyl concentration was significantly higher during intubation in group L, probably secondary to the pharmacokinetic consequences of a decreased CI. New electrocardiographic evidence of myocardial ischemia did not occur in either group. Based on their findings with fentanyl-at-racurium, and their review of the literature, the authors speculate that premedication exerts a significant hemodynamic effect during induction with other narcotic-relaxant combinations. 相似文献
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Metronidazole prophylaxis in colorectal surgery: The need for additional aminoglycoside? 总被引:1,自引:0,他引:1
D. T. Hansell G. J. L. Thomson C. J. Simpson C. Morran D. C. Smith W. McNaught G. Gillespie 《The Journal of hospital infection》1983,4(4):383-390
A randomized double-blind trial was conducted in two phases to compare the efficacy of prophylactic oral and intravenous administration of kanamycin and metronidazole in preventing wound infection and other complications in patients undergoing colorectal surgery, and also to assess the need for inclusion of an aminoglycoside in the prophylactic regimen. Adequate prophylaxis did not depend on the route of antimicrobial administration, but wound infection rates were increased following exclusion of kanamycin. 相似文献
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D J Philbrick J B Hopkins D C Hill J C Alexander R G Thomson 《Journal of toxicology and environmental health》1979,5(4):579-592
Male weaning rats were fed a semipurified diet containing 10% casein; this diet restricted in methionine, vitamin B12, and iodine; or the complete and restricted diets supplemented with either 1500 ppm potassium cyanide or 2240 ppm potassium thiocyanate for 11.5 mo. There were no deaths or clinical signs of toxicity. Cyanide, but not thiocyanate, caused a consistent reduction in weight gain in the complete and restricted groups. Both cyanide and thiocyanate caused decreased thyroid gland activity in young rats, particularly in the restricted groups. Plasma thyroxine concentrations were maintained in the mature cyanide-treated rats, even though secretion rates were decreased. However, the mature thiocyanate-treated animals showed decreased plasma thyroxine concentrations, despite thyroid gland enlargement. Modest primary myelin degeneration in the spinal cord white matter was found in the restricted group and in rats receiving this diet supplemented with either cyanide or thiocyanate. The lesions did not resemble those of a vitamin B12 deficiency in appearance or those of acute cyanide intoxication in distribution. Because of tissue autolysis, it could not be determined whether these changes resulted from histotoxic anoxia or an alteration of oligodendroglial myelin metabolism. 相似文献
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In vitro testing of immunoresponsiveness in patients with inflammatory bowel disease: prevalence and relationship to disease activity immunoresponsiveness in IBD. 下载免费PDF全文
Abnormalities in the numbers and function of thymus and function of thymus-derived and bone marrow-derived lymphocytes (T and B cells) and K cells were determined in sixty-nine consecutive patients with Crohn's disease or ulcerative colitis. Rosetting techniques to identify subpopulations of lymphocytes showed a significant decrease in E-rosettes (T cells) and significant increase in EA- and EAC-rosettes (B cells) in patients with inflammatory bowel disease when compared to normals. In vitro lymphocyte transformation responses to mitogens and antigens were depressed to a variable degree. Mean levels of K cell activity were not significantly different from normal controls. A considerable degree of individual variation was noted in all groups. When the results of each groups were considered, none of the laboratory variables correlated with the site, duration or activity of disease, therapy, presence of iron deficiency anemia, weight loss or hypoalbuminaemia. Thus, in vitro evidence of abnormal immune responses in patients with inflammatory bowel disease cannot be directly related to clinical or laboratory variables and probably reflects a multi-factorial aetiology. 相似文献
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