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BACKGROUND: Allergic reaction is characterized by a complex inflammatory process. Some of the new antihistamines have antiallergic effects and can affect the inflammatory cell recruitment via adhesion molecule downregulation. We aimed to assess in a 12-month study whether continuous treatment with an antihistamine (terfenadine) can reduce respiratory symptoms and local inflammation in children with mite allergy. METHODS: The study was double-blind and placebo-controlled: it involved two parallel groups of children suffering from rhinoconjunctivitis and/or mild intermittent asthma due to mite allergy. They received either terfenadine (1 mg/kg per body weight per day) or placebo for 1 year. Nasal, conjunctival, and bronchial symptoms were recorded by diary cards; at each of the programmed control visits, a nasal scraping for inflammatory cells and ICAM-1 was performed. Some additional clinical parameters were also recorded: days of school absence, extra visits for acute respiratory symptoms, and days of hospital admission. RESULTS: Only children treated with terfenadine achieved significant control of symptoms (P<0.05 in 8 out of 12 months) and allergic inflammation, as shown by inflammatory cell infiltrate and ICAM-1 expression at nasal level (P<0.001), and had significantly fewer extra visits and school absences than the placebo group (P<0.03). No side-effects were reported in either group. CONCLUSIONS: The present study demonstrates that continuous terfenadine treatment (1 mg/kg body weight per day) could decrease respiratory symptoms and allergic inflammation, and it had an additional antiallergic effect in reducing ICAM-1 expression on nasal epithelial cells. Therefore, the present results confirm the efficacy of a long-term therapeutic strategy in controlling allergic inflammation.  相似文献   
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BACKGROUND: Studies examining the relation between bone mineral density (BMD) and fruit and vegetable consumption during adolescence are rare. OBJECTIVE: Our objective was to determine whether usual fruit and vegetable intakes reported by adolescents have any influence on BMD. DESIGN: BMD was measured by dual-energy X-ray absorptiometry at the nondominant forearm and dominant heel in a random sample of 12-y-old boys (n = 324), 12-y-old girls (n = 378), 15-y-old boys (n = 274), and 15-y-old girls (n = 369). Usual fruit and vegetable consumption was assessed by an interviewer-administered diet history method. Relations between BMD and fruit and vegetable intake were assessed by using regression modeling. RESULTS: Using multiple linear regression to adjust for the potential confounding influence of physical and lifestyle factors, we observed that 12-y-old girls consuming high amounts of fruit had significantly higher heel BMD (beta = 0.037; 95% CI: 0.017, 0.056) than did the moderate fruit consumers. No other associations were observed. CONCLUSION: High intakes of fruit may be important for bone health in girls. It is possible that fruit's alkaline-forming properties mediate the body's acid-base balance. However, intervention studies are required to confirm the findings of this observational study.  相似文献   
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OBJECTIVE: To report micronutrient intakes in Northern Ireland schoolchildren, and to establish the contribution of fortified breakfast cereal to overall nutrient intakes and achievement of current dietary recommendations. DESIGN: Analysis of dietary intakes and physical characteristics of participants in a randomly selected 2% population sample of 1015 schoolchildren aged 12 and 15 years in Northern Ireland during the 1990/1 school year. MAIN OUTCOME MEASURES: Dietary intakes, physical characteristics, and their association with consumption of fortified breakfast cereal. RESULTS: Mean micronutrient intakes were generally adequate with the exception of low intakes of folate (boys and girls) and iron (girls). Fortified breakfast cereals, consumed by a high proportion (94% boys; 83% girls) of the sample, were associated with higher daily intakes of most micronutrients and fibre and with a macronutrient profile consistent with current nutritional recommendations. Appreciable proportions of subjects who did not consume fortified breakfast cereals had daily intakes that fell below the lower reference nutrient intake for riboflavin, niacin, folate, vitamin B-12, and iron (girls). CONCLUSIONS: The results demonstrate the potential of fortification in contributing to micronutrient intakes of schoolchildren, particularly where requirements are high, or for those on marginal diets of low nutritional quality.  相似文献   
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Objective : To determine the relationship between lung function at 11 years of age and bronchopulmonary dysplasia (BPD) in very low birthweight (VLBW) children.
Methodology : This study comprised 154 consecutive surviving VLBW children, divided into three groups with respect to their neonatal respiratory morbidity: group I developed BPD; group II required assisted ventilation but did not develop BPD; and group III required no assisted ventilation. Lung function tests were measured on 120/154 (77.9%) children at 11 years of age. The relationship between various lung function variables and neonatal lung disease was analysed by multiple linear regression.
Results : Several lung function variables reflecting airflow were significantly diminished in the BPD group ( n = 15), and residual volume was significantly higher. Despite poorer lung function overall, few children in the BPD group had lung function abnormalities in the clinically significant range ( n = 2 [13.3%] with a forced expired volume in 1 s <75% predicted; n = 2 [13.3%] with a forced vital capacity <75% predicted; n = 1 [6.7%] with a residual volume/total lung capacity >35%). There were no significant differences in lung function variables between group II ( n = 41) and group III ( n = 64). Changes in lung function tests between 8 and 11 years did not vary significantly between the three groups.
Conclusions : VLBW children with BPD in the newborn period have poorer lung function at 11 years of age than other surviving VLBW children without BPD, although few have lung function abnormalities in the clinically significant range.  相似文献   
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Cysteine proteinases have been implicated in astrocytoma invasion. We recently demonstrated that cathepsin S (CatS) expression is up-regulated in astrocytomas and provided evidence for a potential role in astrocytoma invasion (Flannery et al., Am J Path 2003;163(1):175-82). We aimed to evaluate the significance of CatS in human astrocytoma progression and as a prognostic marker. Frozen tissue homogenates from 71 patients with astrocytomas and 3 normal brain specimens were subjected to ELISA analyses. Immunohistochemical analysis of CatS expression was performed on 126 paraffin-embedded tumour samples. Fifty-one astrocytoma cases were suitable for both frozen tissue and paraffin tissue analysis. ELISA revealed minimal expression of CatS in normal brain homogenates. CatS expression was increased in grade IV tumours whereas astrocytoma grades I-III exhibited lower values. Immunohistochemical analysis revealed a similar pattern of expression. Moreover, high-CatS immunohistochemical scores in glioblastomas were associated with significantly shorter survival (10 vs. 5 months, p = 0.014). With forced inclusion of patient age, radiation dose and Karnofsky score in the Cox multivariate model, CatS score was found to be an independent predictor of survival. CatS expression in astrocytomas is associated with tumour progression and poor outcome in glioblastomas. CatS may serve as a useful prognostic indicator and potential target for anti-invasive therapy.  相似文献   
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A review is given of the predetermination of sex in variousdomestic animals and in the human using sperm samples enrichedfor X- and Y-chromosome bearing spermatozoa obtained by flowcytometry and cell sorting. A comparison of other putative methodsof sperm separation is made. In separating human X and Y spermatozoa,measurements of the DNA content in each individual gamete usingthe Hoechst fluorochrome 33342 remains the only validated method.The difference in DNA content between human X and Y spermatozoais 2.8%, and cell sorters have been adapted to take accountof this and the asymmetrical nature of the sperm head. DNA analysesand PCR have been used to validate the method for animal spermatozoa.In the human, fluorescence in-situ hybridization (FISH) hasconfirmed sorting accuracy. Many correctly-diagnosed normaloffspring have been born in various animal species and any potentialmutagenic or cytotoxic effects are being closely monitored asare the cost and efficiency of the technology.  相似文献   
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