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61.
It is postulated that a vigorous host inflammatory response in the cystic fibrosis lung contributes to lung injury. Tumour necrosis factor-alpha (TNF-alpha) may play a part in that process and in the generation of leukotrienes. Therefore, the relationships between sputum TNF-alpha, leukotriene concentration, and lung function abnormalities in 16 children with cystic fibrosis were investigated. Each subject provided sputum samples and performed spirometry. TNF-alpha was measured by enzyme linked immunosorbent assay; individual leukotrienes were separated using high performance liquid chromatography and quantified by radioimmunoassay. The geometric mean concentration of TNF-alpha was 129.7 pg/ml and 95% confidence interval 48.2 to 348.3. Mean (SEM) leukotriene B4 (LTB4) was 97.8 (22.9) pmol/g and total cysteinyl leukotrienes were 60.9 (14.8) pmol/g. Mean (SD) forced expiratory volume in one second (FEV1) of the group was 53 (15)% of predicted and forced vital capacity (FVC) was 65 (14)% of predicted. There was a significant positive correlation between TNF-alpha and both LTB4 and the total cysteinyl leukotriene sputum content. An inverse relationship existed between TNF-alpha and FEV1 and FVC. Moreover, a negative correlation was observed between sputum LTB4 and FEV1 and FVC. These results suggest that TNF-alpha and the leukotrienes may participate in the airways inflammation and airflow obstruction observed in cystic fibrosis subjects and support the hypothesis that TNF-alpha upregulates the 5-lipoxygenase pathway in vivo.  相似文献   
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The cytokines interleukin-1 and interleukin-2 participate in the inflammatory response, and may contribute to hypergammaglobulinaemia G and the development of lung injury in cystic fibrosis. Anti-inflammatory treatment with corticosteroids may attenuate this response. The effect of a 12 week course of oral prednisolone on spirometry and serum concentrations of interleukin-1 alpha (IL-1 alpha), soluble interleukin-2 receptor (sIL-2R), and IgG was investigated in 24 children with cystic fibrosis. Prednisolone was administered, in a double blind and placebo controlled manner, at an initial dose of 2 mg/kg daily for 14 days and tapered to 1 mg/kg on alternate days for 10 weeks. The treated group (n = 12) experienced an increase in forced expiratory volume in one second and forced vital capacity at 14 days, however, these changes were smaller at 12 weeks. In the treated group, change in pulmonary function was associated with decreased serum IgG and cytokine concentrations. Prednisolone suppresses serum concentrations of these cytokines, which may participate in the inflammatory response, the excessive synthesis of IgG, and airflow obstruction observed in cystic fibrosis patients.  相似文献   
63.
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   
64.
Summary A case of sensorimotor neuropathy in a male with malignant glioma is reported. The symptoms of peripheral motor and sensory disturbances preceeded those of the intracranial tumor.The history, clinical findings, electrophysiological and histopathological results are presented, as well as immunological data. A possible causal relationship between glioma and peripheral neuropathy is discussed.
Zusammenfassung Es liegen zahlreiche Veröffentlichungen von peripherer Polyneuropathie bei Patienten mit verschiedenen Malignomen vor. Es wird über einen Fall von sensorimotorischer Polyneuropathie bei einem Mann mit einem malignen Gliom des Gehirnes berichtet. Die Zeichen der peripheren motorischen und sensiblen Störungen manifestierten sich vor denjenigen des intrakraniellen Prozesses.Es wird über Anamnese, klinische Befunde, elektrophysiologische und neuropathologische Untersuchungsergebnisse berichtet sowie über die immunologischen Aspekte. Es wird eine mögliche kausale Beziehung zwischen dem Gliom und der peripheren Polyneuropathie diskutiert.
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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   
70.
Postembolic colonic infarction   总被引:12,自引:0,他引:12  
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