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排序方式: 共有816条查询结果,搜索用时 15 毫秒
1.
Dietary carotenoids and risk of lung cancer in a pooled analysis of seven cohort studies. 总被引:5,自引:0,他引:5
Satu M?nnist? Stephanie A Smith-Warner Donna Spiegelman Demetrius Albanes Kristin Anderson Piet A van den Brandt James R Cerhan Graham Colditz Diane Feskanich Jo L Freudenheim Edward Giovannucci R Alexandra Goldbohm Saxon Graham Anthony B Miller Thomas E Rohan Jarmo Virtamo Walter C Willett David J Hunter 《Cancer epidemiology, biomarkers & prevention》2004,13(1):40-48
Intervention trials with supplemental beta-carotene have observed either no effect or a harmful effect on lung cancer risk. Because food composition databases for specific carotenoids have only become available recently, epidemiological evidence relating usual dietary levels of these carotenoids with lung cancer risk is limited. We analyzed the association between lung cancer risk and intakes of specific carotenoids using the primary data from seven cohort studies in North America and Europe. Carotenoid intakes were estimated from dietary questionnaires administered at baseline in each study. We calculated study-specific multivariate relative risks (RRs) and combined these using a random-effects model. The multivariate models included smoking history and other potential risk factors. During follow-up of up to 7-16 years across studies, 3,155 incident lung cancer cases were diagnosed among 399,765 participants. beta-Carotene intake was not associated with lung cancer risk (pooled multivariate RR = 0.98; 95% confidence interval, 0.87-1.11; highest versus lowest quintile). The RRs for alpha-carotene, lutein/zeaxanthin, and lycopene were also close to unity. beta-Cryptoxanthin intake was inversely associated with lung cancer risk (RR = 0.76; 95% confidence interval, 0.67-0.86; highest versus lowest quintile). These results did not change after adjustment for intakes of vitamin C (with or without supplements), folate (with or without supplements), and other carotenoids and multivitamin use. The associations generally were similar among never, past, or current smokers and by histological type. Although smoking is the strongest risk factor for lung cancer, greater intake of foods high in beta-cryptoxanthin, such as citrus fruit, may modestly lower the risk. 相似文献
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We report two cases highlighting the diversity of vagal nerve stimulation (VNS)‐related effects on voice and breathing in patients with refractory epilepsy. The patients had both implantation and stimulation‐related side effects, which lasted for several months, impacting on their quality of life. The adverse effects appear to be due to recurrent laryngeal nerve paralysis‐related vocal cord hypofunction and stimulation‐related vocal fold spasms, however, their inter‐relationship is complex. In one of the patients, we were able to utilize the novel programming capabilities of the VNS device to reduce the laryngeal side effects without compromising therapeutic efficacy. [Published with video sequences]. 相似文献
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Objectives:To provide an empirical test of the applicability of Locker''s conceptual model of oral health for malocclusion patients, and to suggest alternative models of the effect of malocclusion on well-being.Materials and Methods:Data from a survey of 323 adolescents attending for orthodontic treatment were analyzed to develop a new oral health model for malocclusion patients. Oral health–related quality of life (OHRQoL) was measured using the 14-item Oral Health Impact Profile; malocclusion was measured using the Dental Health Component (DHC) of the Index of Orthodontic Treatment Need (IOTN). Using structural equation modeling, the relationship between conceptual domains in Locker''s model was explored and three models of their interrelationship tested for goodness of fit.Results:Fit indexes for Locker''s model indicated that it did not fit the data well. Therefore, a modified model was developed to incorporate additional paths between other levels to better fit the data. The best fit was provided by a model in which the direct effects of malocclusion on pain, discomfort, and handicapping—and the direct effect of pain on disability—were removed. A direct effect of functional limitation on disability was allowed. The modified Oral Health Impact Profile model proved to be a good fit to the data (root mean square error of approximation = 0.069).Conclusion:The pathways identified in Locker''s (1988) conceptual model of oral health may not be appropriate for describing the relationships between OHRQoL constructs in individuals with malocclusion. An alternative model is proposed. 相似文献
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During pregnancy, metabolic adjustments occur in the mare to preserve iron stores in order to have adequate amounts for the growth and development of the equine fetus. The aim of this study was to analyze the evolution of hematocrit, iron, and ferritin in Spanish Purebred mares during pregnancy. A total of 31 Spanish broodmares aged 4–17 years old were studied during three similar periods of pregnancy (I, II, and III). Hematocrit (packed cell volume, PCV) was determined by microhematocrit and iron and ferritin concentrations were analyzed using spectrophotometry and turbidimetric methods, respectively. Pregnancy in the Spanish mare was characterized by a progressive increase in PCV and serum iron and ferritin concentrations. The physiological state of pregnancy significantly modifies iron status in these animals. In comparison with the first period, the increase in iron stores during the second and third periods indicates a positive iron balance, suggesting that the fetus can tolerate iron levels compatible with the mothers during the entire fetal development process. 相似文献
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Raija Poutanen Satu Lahti Mimmi Tolvanen Hannu Hausen 《Acta odontologica Scandinavica》2013,71(5):286-292
Objective. The aim of this study was to determine whether there are differences between oral health-related knowledge, attitudes, beliefs and behaviors of children and their parents, and to identify the family-related factors associated with children's poor or good oral health-related behavior. Material and Methods. The data were gathered by means of questionnaires from 11–12-year-old schoolchildren and their parents who replied without having knowledge of the answers of the others. Differences between subgroups of children were analyzed by cross-tabulation, and the factors related to children's good or poor oral health-related behavior by logistic regression analyses. Results. Parents of children who reported good oral health-related behavior had better knowledge and more favorable behaviors than those of other parents. Predictors for a child's poor oral health-related behavior were the child's poor knowledge, male gender, the parent's frequent consumption of sweets, and the parent's infrequent use of xylitol gum. When a less strict threshold for the child's poor oral health-related behavior was used, more predictors entered the model: the parent's unfavorable use of fluoride toothpaste; among girls, the parent's lack of knowledge; and among children whose mother's occupation level was high, the parent's infrequent use of xylitol gum. The parents of children whose oral health behavior was favorable were more likely to have a high level occupation and favorable oral health-related behaviors. Conclusions. Oral health-related knowledge of children and their parents seems to be associated with children's oral health-related behavior. Parents’ behaviors, but not attitudes, were associated with children's oral health behavior. 相似文献
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K. Jonas Brännström Lucas Holm Josefina Larsson Sofie Lood Margareta Notsten Satu Turunen Taheri 《International journal of audiology》2016,55(8):447-453
Objective: The present study reports on the application of a Swedish translation of the audiologist occupational stress questionnaire (AOSQ) on audiologists working in Sweden. The relations between AOSQ scores and perceived effort, perceived rewards, coping strategies at work, demographic variables such as salary, education length, practise length, and practice type were tested. Design: A cross-sectional e-mail survey using the AOSQ, effort-reward imbalance questionnaire, and demographic questions. Study sample: Four-hundred and four Swedish licensed audiologists working with clients. Results: The Swedish AOSQ translation demonstrated high inter-item correlations and high internal consistency. Several stress factors were identified: time spent at work, accountability, leadership at the workplace, paperwork and practice demands, equipment and clinical protocols, own health concerns, and job control. The outcome on the complete AOSQ questionnaire was related to perceived effort, perceived rewards, coping strategies at work, and age. Conclusions: The Swedish AOSQ translation seems to provide a valid measure of occupational stress among audiologists. 相似文献
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The purpose of the study was to assess the reliability of the specific multiple sclerosis quality of life (MSQOL-54) instrument, which contains 54 items measuring quality of life, among Finnish multiple sclerosis (MS) patients. Nursing professionals evaluated the clarity and comprehensibility of the translated instrument, after which it was pilot-tested. The data were collected through a questionnaire survey in the spring 2004. Persons diagnosed with MS in 1999-2001 filled in the questionnaire (n = 100). The response percentage was 81%. The structural validity of the MSQOL-54 instrument was evaluated with factor analysis and the generic 15D quality of life instrument. The internal consistency of the instrument was measured with Cronbach's alpha, correlations and item analysis. According to the results, the structural validity of MSQOL-54 was good, and factor analysis yielded a clear-cut factorial model. More than half of the correlations between the comparable items of the 15D and MSQOL-54 instruments were moderate or better. The internal consistency of MSQOL-54 can hence be considered quite good: Cronbach's alpha coefficients calculated for the factors and their items ranged within 0.33-0.89. The alpha coefficient calculated for the whole instrument was 0.84. The internal consistency of MSQOL-54 was further confirmed by the results of an item analysis, which showed the correlation coefficients between the items of the different dimensions to be good (0.31-0.81). On the basis of the test results, the MSQOL-54 instrument is fairly reliable and suitable for assessing the health-related quality of life of MS patients. The reliability of MSQOL-54 should be evaluated further by a longitudinal study design in the future. 相似文献
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