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Objectives Compare the effect of high doses of inhaled corticosteroids on bone loss in subjects with moderate to severe asthma or mild asthma, and examine the influence of dietary intake on bone metabolism. Design A survey on the effects of corticotherapy and nutrition on bone density was conducted in 74 subjects currently being treated for asthma in the asthma clinic of Hospital Laval (Sainte-Foy, Quebec, Canada). Fifty-eight subjects completed the study (attrition RATE=15%).

Main outcome measures In all subjects expiratory volumes were determined and urinary analysis was conducted for hydroxyproline, calcium, phosphorus, and cortisol levels. Osteocalcin, calcium, phosphorus, cortisol, alkaline phosphatase, and γ-glutamyltransferase levels were measured in blood samples. Bone density of the lumbar spine was determined by means of dual-energy x-ray absorptiometry. Nutrition evaluation was based on a 3-day food diary analyzed using progiciel Nutri 91. The nutritional parameters examined were calcium; phosphorus; magnesium; zinc; vitamins A, C, and D; protein; total fiber; oxalates; energy; caffeine; and alcohol in relation to bone density.

Subjects Thirty-one patients with moderate to severe asthma who had been taking more than 1,000 μg beclomethasone per day or the equivalent for more than 2 years and 27 patients with mild asthma who were taking less than 500 μg beclomethasone per day or the equivalent.

Statistical analyses performed Four factor analysis of variance with hierarchized interactions of four levels, Duncan's test, Pearson correlation coefficients.

Results Blood levels of osteocalcin and protein intake were lower in patients with moderate to severe asthma than in those with mild asthma (P<.05). Significant correlations (P<.02) were observed between bone density and calcium intake (r=.40), phosphorus intake (r=.35), protein intake (r=.30), and serum alkaline phosphatase level (r=−.30). Bone density was not significantly different between the two groups of patients with asthma.

Applications A follow-up of patients with asthma who are taking inhaled corticosteroids is needed to assess bone density, osteocalcin levels, and dietary intakes of calcium. Verify if osteocalcin level decreases over time in patients with moderate to severe asthma, monitor possible modifications in bone density, and verify if the correlation between dietary calcium and bone density is maintained. J Am Diet Assoc. 1997;97:1401–1406.  相似文献   

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Sonoelasticity imaging of prostate cancer: in vitro results   总被引:2,自引:0,他引:2  
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Summary Adrenaline, when administered in dental local anaesthetic solutions, significantly reduces the plasma potassium concentration in young healthy adults. This effect occurs within 10 min of extravascular injections into the maxillary buccal sulcus and may influence the choice of local anaesthetic solution for patients receiving kaliuretic diuretics.  相似文献   
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A lawsuit directed by parents at a day care program following an outbreak of infectious disease would most likely be based on the legal theory of negligence--the failure to exercise due care as required by circumstances. In the determination of liability for infectious diseases in child day care, the element of causation is most critical. Did the day care facility's actions or failure to act cause the harm? Another important question is whether an infectious disease can be occupational and under what circumstances. Although worker's compensation laws initially had no provisions for occupational disease, now all states recognize responsibility for them. Awareness of potential problems with legal liability and establishment of procedures to minimize risk are important for day care providers, public health officials, clinicians, and parents.  相似文献   
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