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OBJECTIVE: To determine if bronchodilators are efficacious in treating bronchiolitis. DATA SOURCES: A search of bibliographic databases (MEDLINE, Excerpta Medica, and Reference Update) for bronchiolitis and albuterol or ipratropium bromide, or adrenergic agents or bronchodilator agents. Reference lists were also used. STUDY SELECTION: Randomized, placebo-controlled trials of bronchodilator treatment in bronchiolitis were selected by 2 investigators. Fifteen of 89 identified publications met the selection criteria. DATA EXTRACTION: Investigators independently abstracted data for 3 outcomes: clinical score, oxygen saturation, and hospitalization. Clinical score was measured as a dichotomous variable (score +/- improved) or continuous variable (average score). DATA SYNTHESIS: For primary analysis, data were pooled from 8 trials of children with first-time wheezing. The effect size for average score was -0.32 (95% confidence interval [CI], -0.54 to -0.11; P < .01), favoring treatment; the relative risk for score +/- improved was 0.76 (95% CI, 0.60 to 0.95; P = .02), favoring treatment. Bronchodilators had no effect on hospitalization (relative risk, 0.85; 95% CI, 0.47 to 1.53; P = .58), but co-interventions may have been administered prior to this outcome. The results for oxygen saturation were too varied to allow pooling of the results. Secondary analyses were performed on 4 outpatient trials of children with first-time wheezing, 7 trials in which only nebulized beta-agonists were used, and on all 15 trials identified. The results were similar, but the data varied more. CONCLUSION: Bronchodilators produce modest short-term improvement in clinical features of mild or moderately severe bronchiolitis. 相似文献
817.
IT Gaga?o EE Ha? KZ Korolkiewicz MT Matuszek Z Szreder 《Canadian Metallurgical Quarterly》1996,84(3):289-290
Thermoregulatory responses after treatment with nitric oxide (NO) donor, sodium nitroprusside (SNP-3 mg/kg/h), or NO synthase inhibitor, NG-nitro-L-arginine methylester (L-NAME-100 mg/kg) were investigated in febrile rabbits (lipopolysaccharide E. coli-1 meg/kg). Pretreatment with SNP attenuated pyrogen fever as well as metabolic rate. L-NAME also inhibited postpyrogen increases in metabolism; however, this effect did not lead to antipyresis. 相似文献
818.
The effects of H2O2-induced oxidative DNA damage in 80 healthy individuals with relation to age (20-25 and 55-60 years old) and smoking has been investigated with the comet assay technique. Both factors have shown a significant effect upon basal DNA damage with smoking appearing to have the most impact. A differentiation of the four groups response to induced oxidative damage was also observed. A distinctly separate behavior of the younger non-smokers group, when compared with the rest of the categories, was found. This is attributed to the lower degree of initial basal damage that occurs in their lymphocytes. 相似文献
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The maturity of full-term newborns was studied by immunological, biochemical, and ecogenetic methods. The study yielded basic immunochemical and ecogenetic evidence. It shows that chronic intrauterine hypoxia and unfavourable ecogenetic factors apparently influence concurrently and result in severe fetal immaturity. 相似文献