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91.
Background: Trends in the care of patients with cancer are monitored annually by the Commission on Cancer of the American College of Surgeons. In 1991 a patient care evaluation study of breast cancer was conducted, which among other questions examined the correlation of health insurance with type or quality of care delivered for breast cancer on a national basis. Methods: The tumor registry system of the American College of Surgeons was used to obtain data on patients with breast cancer diagnosed in 1983 and 1990. Trends in diagnosis and treatment were correlated with the type of insurance or lack of insurance. Results: Data were obtained from hospitals in 50 states on a total of 41,651 patients. The largest number of patients were covered by Medicare. Fewer than 5% were considered medically indigent. Medically indigent patients presented with higher stage disease and did not participate in a trend toward downstaging, which occurred between the two study years. The treatment of medically indigent patients appeared to be appropriate and comparable with better insured patients. Insurance type (health maintenance organization vs. private) did not affect stage, treatment, or outcome. Decisions to use controversial therapies, such as chemotherapy for stage I disease, did not appear to be financially driven. Conclusion: A nationwide pattern of care study for breast cancer indicates that medically indigent patients present with more advanced disease compared with better insured patients, but once the diagnosis is made, treatment and outcome have little to do with insurance type.  相似文献   
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Summary— Mivazerol is a new compound that could potentially reduce perioperative cardiovascular morbidity and mortality in patients with or at risk of coronary disease and submitted to surgery. This action of mivazerol depends on a well documented centrally mediated reduction in sympathetic nerve activity, but a direct peripheral decrease in sympathetic neurotransmitter release induced by activation of prejunctional α2-adrenoceptors located on sympathetic nerve endings could also contribute. To investigate this issue, the effects of mivazerol on the pressor, systemic and regional hemodynamic (pulsed Doppler technique) as well as on the cardiac responses to electrical stimulation of the spinal cord (SCS) were measured in pithed rats in the absence and in the presence of mivazerol. Mivazerol exerted strong sympathoinhibitory effects: SCS-induced increases in blood pressure, total peripheral resistance and heart rate were dose-dependently reduced by mivazerol, but among the regional vascular beds investigated, only the hindlimb vasoconstrictor responses were significantly drug-affected. All these sympathoinhibitory effects of mivazerol were abolished by prior yohimbine administration. Simultaneously, mivazerol did not induce any postjunctional adrenoceptor blockade as it did not affect noradrenaline cardiac and hemodynamic effects. On the contrary, through postjunctional α2-adrenoceptor stimulation, mivazerol, in this pithed preparation, dose-dependently increased blood pressure, total peripheral and hindlimb vascular resistances, but heart rate was not affected. We conclude that, in the pithed rat, mivazerol exerts strong peripheral sympathoinhibitory effects. The mechanism involved is prejunctional α2-adrenoceptor activation as i) mivazerol does not display any postsynaptic α-adrenoceptor blocking effect — it even behaves as a postsynaptic α2-adrenoceptor agonist — and ii) yohimbine abolishes mivazerol's sympathoinhibitory effects. Thus, direct peripheral together with central mechanisms contribute to mivazerol's sympathoinhibitory effects and ultimately to its cardioprotective action.  相似文献   
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The authors describe a simple technique for diagnosis of tricuspid regurgitation. Red blood cells were labeled in vivo with 99mTc and 22 patients were studied with ECG-gated blood-pool imaging of the liver. A single region of interest was manually drawn around the liver and a time-activity curve obtained. The per cent change in liver counts during the cardiac cycle was found to be significantly higher in the 12 patients with tricuspid regurgitation (Group I) (mean, 4.04 +/- 1.6%; range, 1.3-21.4%) compared with the 10 controls (Group II) (mean, 0.35 +/- 0.16%; range, 0.013-1.3%) (p less than 0.05). Using a 1% change in liver counts as the criterion of a positive study, all 12 cases in Group I were diagnosed correctly, but there was one false positive in Group II; thus the sensitivity was 100% and the specificity 90%.  相似文献   
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Charcoal haemoperfusion is used in the treatment of severe drug overdosage, and is potentially useful in fulminant hepatic failure and chronic uraemia. Haemo-compatibility of early devices has improved, but platelet loss and occasional associated haemorrhage still occur. During a double blind cross-over study, in 8 healthy male volunteers, aspirin 600 mg/day, sulphinpyrazone 800 mg/day, or a combination of both or placebo were administered for 2 days at 14 day or longer intervals. The effects of these agents were measured with reference to 1) forearm bleeding times using a spring loaded device, 2) platelet adsorption during 2 hrs haemoperfusion of heparinized blood through 2% acrylic hydrogel coated or uncoated activated charcoal in vitro, and 3) platelet retention from citrated blood on PT150 and PT250 cuprophan dialysis membranes in vitro. Aspirin and aspirin in combination with sulphinpyrazone prolonged bleeding time, but sulphinpyrazone alone had no significant effect on bleeding time. Aspirin alone, sulphinpyrazone alone, and their combination reduced platelet adsorption on coated activated charcoal, and platelet retention on cuprophan membranes. Aspirin, and aspirin in combination with sulphinpyrazone, reduce platelet adsorption on uncoated charcoal, while sulphinpyrazone alone had no significant effect. The results indicate that 2 days treatment with sulphinpyrazone or aspirin produce significant antiplatelet action and that the effects of sulphinpyrazone on platelet function should be explored in relation to clinical haemoperfusion and haemodialysis.  相似文献   
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Postembolic colonic infarction   总被引:12,自引:0,他引:12  
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