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81.
Important asthma outcomes such as lung function and bronchial hyperresponsiveness are probably determined in early childhood. Early and longitudinal objective assessment of lung function and bronchial hyperresponsiveness is necessary to enable early diagnosis, monitor intervention and improve prognosis in preschool children. Cold air challenge and plethysmographic measurement of specific airway resistance (sRaw) are feasible candidate methods for diagnosis, clinical monitoring and research during this critical period of lung growth and development. Methodology and practical aspects of cold air challenge and assessment of sRaw in preschool children are reviewed. Reference values are provided for sRaw and have allowed discrimination between health and respiratory disease, both in cross-sectional and longitudinal studies. Bronchial hyperresponsiveness can be determined with acceptable repeatability and provides good discrimination between asthmatics and healthy. The effects of classic anti-asthmatic therapies have also been documented with these techniques. The need for further standardisation and improvement of these methods and future perspectives are outlined.  相似文献   
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BACKGROUND: Preoperative oral carbohydrate can attenuate postoperative insulin resistance and catabolism, and may have the potential to improve postoperative recovery. There are no data from randomized studies on postoperative clinical outcome after specific surgical procedures. This study evaluated the clinical effects of a preoperative carbohydrate beverage in patients undergoing laparoscopic cholecystectomy. METHODS: Ninety-four patients undergoing laparoscopic cholecystectomy were included in a randomized clinical trial. Patients were randomized to receive 800 ml of an iso-osmolar 12.5 per cent carbohydrate-rich beverage the evening before operation (100 g carbohydrate) and another 400 ml (50 g carbohydrate) 2 h before initiation of anaesthesia, or the same volume of a placebo beverage. The primary endpoint was general well-being the day after operation. Patients were evaluated from 5 days before to 5 days after operation. Daily scores of general well-being, fatigue, appetite and pain, computerized measurements of physical activity and sleep (actigraphy), and subjective sleep quality were recorded. Nausea and vomiting were assessed twice within the first 24 h after surgery. RESULTS: Data from 86 patients were available for statistical analysis, 43 in each treatment group. No significant intergroup differences in general well-being or any other outcome variable were found. CONCLUSION: A preoperative carbohydrate beverage did not improve clinical outcome after laparoscopic cholecystectomy.  相似文献   
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Newcastle disease virus isolates from chickens in eastern Uganda in 2001 were found to be velogenic by fusion protein cleavage site sequence analysis and biological characterization; the intracerebral pathogenicity index was 1.8. Analysis of their hemagglutinin-neuraminidase protein gene sequences revealed a novel genotype unrelated to those that caused previous outbreaks.  相似文献   
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Hematological parameters, serum cobalamin and folate levels, and the concentrations of the functional markers plasma methylmalonic acid and total homocysteine were determined in 173 newborns and 46 infants at 6 weeks to see whether maternal smoking influences the hematological parameters and the vitamin status of the newborn. At birth, there was a strong inverse correlation between the number of cigarettes smoked per day during pregnancy and red blood cell count (r = -0.56, p = 0.001) and hemoglobin level (r = -0.52, p = 0.003) in the newborns. Neonates born to smoking mothers had lower red blood cell counts and lower hemoglobin and serum cobalamin levels as compared with infants born to nonsmoking mothers. At 6 weeks, maternal smoking significantly predicted the methylmalonic acid and total homocysteine levels, suggesting an influence from smoking on the cobalamin function in these infants.  相似文献   
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BACKGROUND: The 5,10-methylenetetrahydrofolate reductase gene (MTHFR) 677C-->T polymorphism modifies the risk of coronary artery disease and colon cancer and is related to plasma concentrations of total homocysteine (tHcy). Riboflavin status modifies the metabolic effect of the polymorphism, and thyroid hormones increase the synthesis of flavin cofactors. OBJECTIVE: The aim of the study was to investigate the phenotypic expression of the MTHFR 677C-->T polymorphism in terms of plasma tHcy concentrations in patients with thyroid dysfunction. DESIGN: The study population consisted of 182 patients with hyperthyroidism. We studied plasma tHcy in relation to MTHFR genotype, riboflavin, and folate before and during 6 mo of treatment with antithyroid drugs. RESULTS: Before treatment, tHcy was higher in patients with the mutant enzyme than in those with the wild-type enzyme. A genotype effect was observed only at low riboflavin or folate concentrations (P T polymorphism, possibly by modifying the availability of flavin cofactors.  相似文献   
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Rationale The active placebo hypothesis states that placebo effects are potentiated when an active drug is administered.Objective This hypothesis was tested in an experiment where information about the effect of a drug was combined with administration of an active drug or placebo.Methods Information that a drug acted as a relaxant, a stimulant, or as a placebo was crossed with oral administration of a relaxant drug (700 mg carisoprodol), a stimulant drug (400 mg caffeine) or placebo (lactose) in healthy volunteers (n=94). Dependent variables were subjective and physiological measures of arousal, as well as serum carisoprodol and caffeine levels. Data were collected from 15 to 280 min after administration of drug or placebo.Results Caffeine increased alertness, systolic and diastolic blood pressure, startle blink reflexes, and skin conductance responses. Subjects were calmer after carisoprodol, and heart rate was increased. There was a positive correlation between increased arousal and carisoprodol levels when stimulant information had been provided. However, this was only seen when carisoprodol levels were very low. There was no evidence that caffeine modulated the placebo response.Conclusions Active placebo responses were seen only transiently when carisoprodol levels were low, and only in the subjective arousal data. Caffeine did not support active placebo responses. The overall findings did not favour the active placebo hypothesis.  相似文献   
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