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OBJECTIVE: To investigate whether cardiovascular mortality related to obesity could be modified by physical activity. DESIGN: Mortality follow-up. SETTING: Population study. PARTICIPANTS: Participants in a health survey: 34 868 women and 32 872 men free from known cardiovascular disease or diabetes at baseline. MAIN OUTCOME MEASURES: Total cardiovascular mortality. MAIN RESULTS: During 16 years of follow-up, 3026 women and 3526 men had died from cardiovascular causes. In middle age, obesity [body mass index (BMI) of 30 or higher] was associated with increased risk of cardiovascular death, but the association weakened with age. After 70, there was no association between BMI and cardiovascular death. At all ages, a lower level of physical activity was associated with a higher cardiovascular mortality. In women with high physical activity, indicated by at least 30 min of moderate to vigorous activity more than once a week, cardiovascular mortality was only slightly higher in the obese compared to lean women (adjusted relative risk, 1.27; 95% confidence interval, 0.80-2.00). In men with high physical activity, cardiovascular mortality was, however, significantly higher among the obese (relative risk, 1.62; 95% confidence interval, 1.09-2.40). In both genders cardiovascular mortality was substantially higher in obese people who reported no regular physical activity compared to obese people with a high level of physical activity. CONCLUSION: In obese women, being highly active may, to a large extent, compensate for the risk-increasing effect of being obese, whereas in obese men who engage in a high level of physical activity, the risk of cardiovascular death may be higher than in lean and equally active men.  相似文献   
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BACKGROUND: Feather bedding has long been considered as a potential source of allergen exposure and thus a potential risk factor for allergic diseases. However, recent cross-sectional studies have reported a higher risk of allergic diseases among users of synthetic bedding compared with feather-bedding users. OBJECTIVE: To explore associations between early life exposure to feather bedding and the risk of developing asthma allergic rhinitis in childhood. METHODS: We assessed the association between early life exposure to feather quilts and the risk of bronchial obstruction during the first 2 years of life and asthma and allergic rhinitis in a prospective 4-year cohort study of 2531 Norwegian children. RESULTS: At the age of 6 months, 24% of the children had a quilt with feathers, decreasing to 20% at the age of 2 years. The adjusted odds ratio for bronchial obstruction 0 to 2 years by exposure to a feather quilt at the age of 6 months was 0.59, 95% confidence interval 0.41 to 0.86, for asthma at the age of 4 years 0.38, 0.23 to 0.64 and for allergic rhinitis at the age of 4 years 0.73, 0.43 to 1.18. CONCLUSION: The use of a feather quilt in early life does not seem to increase the risk of asthma and allergic rhinitis later in childhood.  相似文献   
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Selnes A  Nystad W  Bolle R  Lund E 《Allergy》2005,60(7):894-899
BACKGROUND: During the last decades there has been extensive epidemiological research to explore the increasing prevalence of asthma and allergy in childhood. The worldwide variations in prevalence of these diseases necessitate regional rapports. Furthermore, time-trend analyses with comparable methods are important in order to monitor the rapidly changing prevalence of these diseases. METHODS: Three cross-sectional questionnaire-based studies of asthma and allergy in schoolchildren were conducted in the counties of Troms and Finnmark, in northern Norway in 1985, 1995 and 2000. The two former studies included children from randomly selected primary schools (n = 1794/1985, n = 1432/1995). The latter study was a part of ISAAC-II Europe study (n = 3853). Identical items of asthma and allergy were employed. The analyses comprised only children 9-11 years of age. RESULTS: The prevalence of asthma was 9.3, 13.2 and 13.8% in 1985, 1995 and 2000, respectively. However, great gender differences were detected; the prevalence of asthma increased in males from 1995 to 2000, from 14.1 to 17.0%, RR = 1.2 (95% CI 1.0-1.5), but decreased in females 1995 to 2000, from 12.3 to 10.5%, RR = 0.9 (95% CI 0.7-1.1). Furthermore, in children with asthma, a changing trend was found in the external factors that perceived symptoms, from typical allergens towards other, unspecific agents. The prevalence of self-reported atopic eczema/dermatitis syndrome (AEDS) was 13.4, 21.1 and 20.8% in 1985, 1995 and 2000, respectively. The prevalence of self-reported allergic rhinoconjunctivitis was in 16.5, 24.7 and 29.6% 1985, 1995 and 2000, respectively, RR (2000/1995) = 1.2 (95% CI 1.1-1.3). CONCLUSION: The prevalence of asthma in girls has reached a plateau and even decreased from 1995 to 2000 which is in contrast to the asthma prevalence in boys that tends to continuously increase. The prevalence of AEDS which increased substantially between 1985 and 1995 did not change from 1995 to 2000. However, the prevalence of allergic rhinoconjunctivitis increased steadily from 1985, 1995 to 2000.  相似文献   
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Extraskeletal myxoid chondrosarcoma is a rare malignant soft tissue tumour that can be difficult to diagnose correctly, especially preoperatively. We describe four cases of extraskeletal myxoid chondrosarcoma of the extremities diagnosed by a multimodal approach. The cytological examination of fine-needle aspirates showed small and round, mildly pleomorphic cells lying in sheets and cords, but also dispersed within a myxoid and metachromatic intercellular substance. Histological, electron microscopic and immunocytochemical examination also yielded findings compatible with the diagnosis of extraskeletal myxoid chondrosarcoma. Cytogenetic analysis demonstrated a t(9;22)(q22;q12) in two tumours and a t(9;17)(q22;q11) in the third and fourth. The translocation t(9;22)(q22;q12) has been described repeatedly in extraskeletal myxoid chondrosarcoma but never in other tumours; hence, the detection of this pathognomonic chromosome abnormality in short-term cultured cells from fine-needle aspirates verified the diagnosis in two of the cases. The t(9;17)(q22;q11) found in the last two cases probably represents a new cytogenetic subgroup of extraskeletal myxoid chondrosarcoma as it, too, is unknown in other contexts. The multimodal approach taken in these four cases enabled a definite diagnosis of a rare malignant tumour whose cytological and histological features alone are usually not sufficiently distinct to rule out other differential diagnostic possibilities. Received: 16 March 1999 / Accepted: 1 June 1999  相似文献   
6.
Day care attendance, recurrent respiratory tract infections and asthma   总被引:5,自引:0,他引:5  
OBJECTIVE: Our objective was to use a causal model for childhood asthma to determine whether the effect of day care attendance on asthma was mediated by recurrent respiratory tract infections. DESIGN: A cross-sectional survey among 1447 children aged 6-16 years in Oslo. Their parents completed written questionnaires. A recursive logit model was used to estimate direct effects in terms of adjusted odds ratios (aOR). RESULTS: Year of birth, number of siblings and length of maternal education were significantly associated with day care attendance. Attendance at day care increased the risk of early infections, aOR = 1.8 (1.3-2.5), and infections were associated with asthma, aOR = 4.9 (3.4-7.3). The crude association between day care and asthma was cOR = 1.5 (1.0-2.2), whereas the estimated direct effect was small and nonsignificant, aOR = 1.2 (0.8-1.9). The results may be influenced by overreporting of infections among parents of children with asthma. CONCLUSIONS: Our results suggest that children who attend day care have an increased risk of asthma with early infections as a mediator of risk.  相似文献   
7.
The role of exposure to ambient air pollution has been a topic of interest as a potential risk factor for respiratory symptoms and asthma. We expected that the prevalence rates would vary in Norway between the capital, Oslo, the mountainous area Hallingdal and the industrial area Odda. Surveys were conducted in school children, aged 6-16 years, in; Oslo (n=2577), Hallingdal (n=1177) and Odda (n=831). The parent-reported prevalence of wheeze in past year was almost similar in Oslo (13. 1 (95% CI 11. 7-14. 5)) and Upper Hallingdal (14. 2 (13. 1–15. 3)), but lower in Odda (9. 0 (7. 0–11. 0)). The findings for severe respiratory symptoms were almost equal. The age patters within each area differed. The risk of wheeze ever (p < 0.001) and wheeze in past year (p=0.04) decreased with increasing age in Odda, while there was an increase in the risk of exercise induced wheeze in Oslo (p=0.02) and Hallingdal (p < 0.001). The lifetime prevalence of asthma was lowest in Odda (5. 4 (3. 8–7. 0)) compared to Oslo (9. 4 (8. 2–10. 6)) and Hallingdal (8. 5 (6. 8–10. 2)). There was a positive association between physical activity and wheeze in past year. The results do not support the hypothesis that respiratory morbidity is more common in urban than rural areas, age and physical activity can influence the prevalence rates of respiratory symptoms in school children.  相似文献   
8.
It has been suggested that environmental exposures and living conditions can explain some of the worldwide variation in atopic disorders. Norway has large environmental contrasts within the country. We compared skin prick sensitization rates among school children living in the southern subarctic and in the northern artic part of Norway. Approximately one quarter of the children were sensitized, mostly against pollen and animal dander, while mite and mould sensitization seemed to be a minor problem. Sensitization rates and profiles were similar in the north and south despite differences in living conditions and environmental exposures.  相似文献   
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