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101.
BackgroundAllergic rhinitis (AR), allergic conjunctivitis (AC), and asthma composing multiple phenotypes and improved understanding of these phenotypes and their respective risk factors are needed.ObjectivesThe objective of this study was to define the prevalence of AR, AC, and asthma and their association with allergen‐specific immunoglobulin E (sIgE) sensitization in a large cohort of blood donors and identify risk factors.MethodsFrom the nationwide population‐based Danish Blood Donor Study, 52,976 participants completed an electronic questionnaire including AR, AC, asthma, allergic predisposition, and childhood residence. Of these, 25,257 were additionally tested for sIgE to inhalation allergens (Phadiatop).ResultsThe prevalence of sIgE sensitization, AR, AC, and asthma was 30%, 19%, 15%, and 9%, respectively. The youngest birth cohorts had the highest prevalence of sIgE sensitization and symptoms of asthma, AR, and AC, and for asthma, they apparently experienced symptoms at an earlier age. The sIgE sensitization was positively associated with male sex. The sIgE seroprevalence was higher in participants with both AR and AC (ARC) than in participants with either AR or AC. Allergic predisposition and sIgE sensitization increased the risk of the diseases, while farm upbringing was associated with reduced prevalence of ARC, however, only in sIgE sensitized participants.ConclusionBirth year, childhood residence, sIgE sensitization, and allergic predisposition were associated with asthma, AR, and AC prevalence. Individuals with self‐reported ARC represent a primarily sIgE‐positive phenotype, while those with either AR or AC represent more diverse phenotypes.  相似文献   
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BackgroundIncreased age has been shown to be associated with weaker external rotators and stronger internal rotators of the shoulder in pitchers and tennis players. Whether this age-associated change is present in elite badminton players is unknown.PurposeTo compare the internal and external rotation strength of the shoulder in adolescent and adult elite badminton players.Study designCross-sectional.MethodsThirty-one adolescent (12 females aged 16.8 ± 1.6 years and 19 males aged 17.1 ± 1.6 years) and 29 adult (10 females aged 25 ± 2.9 years and 19 males aged 26.2 ± 4.6 years) national level badminton players were tested pre-seasonally for external rotation (ER) and internal rotation (IR) isometric muscle strength bilaterally, using a hand-held dynamometer. Within-group ER to IR strength ratios were calculated (ER/IR×100%).ResultsThe adolescents had stronger shoulder ER than the adults on both sides (p < 0.05). The adult males tended to have stronger IR of the dominant shoulder than the adolescent males (p = 0.071). In the dominant shoulders, the strength ratios for adult females and males were 77% and 78%, respectively, while the same ratio for adolescent females and males were 85% and 99%, respectively. In the non-dominant shoulders, the ER/IR strength ratios for adult females and males were 90% and 87%, respectively, while the ratios for adolescent females and males were 116% and 102%, respectively.ConclusionThis study is the first to demonstrate that in shoulder injury-free national team badminton players, adolescents have stronger shoulder ER than adults on both sides. Therefore, increased age appears to be associated with weaker shoulder ER muscles in elite badminton players.Level of evidence3b.  相似文献   
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The progression rate of iron overload in hereditary hemochromatosis in individuals in the general population is unknown. We therefore examined in the general population iron overload progression rate in C282Y homozygotes. Using a cohort study of the Danish general population, The Copenhagen City Heart Study, we genotyped 9174 individuals. The 23 C282Y homozygotes identified were matched to 2 subjects each of 5 other HFE genotypes with respect to sex, age, and alcohol consumption. As a function of biologic age, transferrin saturation increased from 50% to 70% from 25 to 85 years of age and from 70% to 80% from 35 to 80 years of age in female and male C282Y homozygotes, respectively. Equivalently, ferritin levels increased from 100 to 500 µg/L and decreased from 800 to 400 µg/L in female and male C282Y homozygotes. As a function of 25 years follow-up irrespective of age, transferrin saturation and ferritin levels increased slightly in male and female C282Y homozygotes. None of the C282Y homozygotes developed clinically overt hemochromatosis. In conclusion, individuals in the general population with C282Y homozygosity at most demonstrate modest increases in transferrin saturation and ferritin levels, and clinically overt hemochromatosis is rare. Therefore, C282Y homozygotes identified during population screening, and not because of clinically overt hemochromatosis, at most need to be screened for manifestations of hemochromatosis every 10 to 20 years. (Blood. 2004;103: 2914-2919)   相似文献   
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OBJECTIVE: To explore the presence of changes resembling rheumatoid arthritis erosions and synovitis in metacarpophalangeal (MCP) and wrist joints of healthy individuals on magnetic resonance imaging (MRI) and to compare the MRI findings with conventional radiographic, clinical, and biochemical findings. METHODS: Twenty-eight healthy individuals were studied. Contrast-enhanced MRI and conventional radiography of the dominant wrist and second through fifth MCP joints were performed, coupled with standard clinical assessments and biochemical analyses. MR images were evaluated according to the latest OMERACT (Outcome Measures in Rheumatology Clinical Trials) recommendations with respect to synovitis, erosions, and bone marrow edema. RESULTS: Conventional radiography revealed erosion-like changes in 1 of 224 MCP joint bones (0.4%) and in 1 of 420 wrist joint bones (0.2%). MRI depicted low-grade erosion-like changes in 5 of 224 MCP joint bones (2.2%) and in 7 of 420 wrist joint bones (1.7%), but postcontrast enhancement within the lesion was detected in only 8.3% of these. MRI depicted low-grade synovitis-like changes in 10 of 112 MCP joints (8.9%) and in 8 of 84 assessed wrist areas (9.5%), while only minimal early synovial enhancement was detected by dynamic MRI. Three subjects had elevated serum levels of C-reactive protein, and these subjects displayed 44.5% of the synovitis-like changes and 41.7% of the erosion-like changes. Bone marrow edema-like changes were not found in any joints. CONCLUSION: Changes resembling mild synovitis or small bone erosions are occasionally found in the MCP and wrist joints of healthy controls. Signs of synovitis on dynamic MRI, enhancement within bone erosion-like changes, and signs of bone marrow edema appear rarely or are absent in healthy controls. These signs may thus prove to be very specific in the distinction between arthritic and normal joints.  相似文献   
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