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Few studies have examined the impact of socioeconomic status on the incidence of asthma and respiratory symptoms. Between 1985 and 1996/97, we conducted an 11-years community cohort study with 2819 subjects, aged 15-70 years at baseline, in Western Norway. We examined the cumulative incidence of asthma and respiratory symptoms by educational level (primary, secondary, and university), as well as estimating the odds ratios (ORs) of educational level on the incidences, after adjustment for sex, age, hay fever, smoking habits, pack years, and occupational exposure. For all respiratory symptoms, the incidences decreased with increasing educational level. The cumulative incidence of asthma was 5.3%, 4.1%, and 1.8%, respectively, for those with a primary educational level, secondary educational level, and university level. Subjects with a primary educational level had adjusted ORs (95% CI) from 1.4 (0.9, 2.3) for the incidence of chronic cough to 2.5 (1.6, 4.0) for the incidence of dyspnea grade 2, compared to those with a university level education. The adjusted OR (95% CI) for the incidence of asthma was 2.1 (1.01, 4.4) in subjects with a primary educational level, and 2.0 (1.04, 3.6) in subjects with a secondary educational level, compared to subjects with a university educational level. In conclusion, subjects with a lower educational level had a higher risk of developing asthma and respiratory symptoms, after adjustment for sex, age, hay fever, smoking, and occupational exposure.  相似文献   
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OBJECTIVE: The Pfcrt-gene encodes a transmembrane protein located in the Plasmodium falciparum digestive vacuole. Chloroquine resistant (CQR) strains of African and Southeast Asian origin carry the Pfcrt-haplotype (c72-76) CVIET, whereas most South American and Papua New Guinean CQR stains carry the SVMNT haplotype. METHOD: Eighty-eight samples from an area with reported in vivo Chloroquine and in vitro Amodiaquine-resistance were screened for the K76T mutation and their Pfcrt-haplotype (c72-76) using a new SSOP-ELISA. RESULTS: Hundred percent of the analysed samples showed the K76T mutation which is highly associated with in vivo drug failure. This very high rate of a CQR-marker is alarming in an area were CQ is still used as first line drug. The distribution of the three main Pfcrt-haplotypes was as follows: 68% CVIET, 31% SVMNT, 0% CVMNT. CONCLUSIONS: These data show, for the first time, the South American/PNG -haplotype (SVMNT) on mainland Southeast Asia. SVMNT-haplotype and others might be associated with a decreased efficacy of Amodiaquine and could therefore be potential markers for of amodiaquine resistance (AQR). If there is a correlation between AQR and the SVMNT-haplotype as suggested, 31% prevalence of a potential resistance marker is cause for concern.  相似文献   
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Ganz T  Olbina G  Girelli D  Nemeth E  Westerman M 《Blood》2008,112(10):4292-4297
We developed and validated the first serum enzyme-linked immunosorbent assay for hepcidin, the principal iron-regulatory hormone that has been very difficult to measure. In healthy volunteers, the 5% to 95% range of hepcidin concentrations was 29 to 254 ng/mL in men (n = 65) and 17 to 286 ng/mL in women (n = 49), with median concentrations 112 versus 65 (P < .001). The lower limit of detection was 5 ng/mL. Serum hepcidin concentrations in 24 healthy subjects correlated well with their urinary hepcidin (r = 0.82). Serum hepcidin appropriately correlated with serum ferritin (r = 0.63), reflecting the regulation of both proteins by iron stores. Healthy volunteers showed a diurnal increase of serum hepcidin at noon and 8 pm compared with 8 am, and a transient rise of serum hepcidin in response to iron ingestion. Expected alterations in hepcidin levels were observed in a variety of clinical conditions associated with iron disturbances. Serum hepcidin concentrations were undetectable or low in patients with iron deficiency anemia (ferritin < 10 ng/mL), iron-depleted HFE hemochromatosis, and juvenile hemochromatosis. Serum hepcidin concentrations were high in patients with inflammation (C-reactive protein > 10 mg/dL), multiple myeloma, or chronic kidney disease. The new serum hepcidin enzyme-linked immunosorbent assay yields accurate and reproducible measurements that appropriately reflect physiologic, pathologic, and genetic influences, and is informative about the etiology of iron disorders.  相似文献   
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BackgroundE-therapies for depression and anxiety rarely account for lesbian and gay users. This is despite lesbians and gay men being at heightened risk of mood disorders and likely to benefit from having access to tailored self-help resources.ObjectiveWe sought to determine how e-therapies for depression and anxiety could be improved to address the therapeutic needs of lesbians and gay men.MethodsWe conducted eight focus groups with lesbians and gay men aged 18 years and older. Focus groups were presented with key modules from the popular e-therapy “MoodGYM”. They were asked to evaluate the inclusiveness and relevance of these modules for lesbians and gay men and to think about ways that e-therapies in general could be modified. The focus groups were analyzed qualitatively using a thematic analysis approach to identify major themes.ResultsThe focus groups indicated that some but not all aspects of MoodGYM were suitable, and suggested ways of improving e-therapies for lesbian and gay users. Suggestions included avoiding language or examples that assumed or implied users were heterosexual, improving inclusiveness by representing non-heterosexual relationships, providing referrals to specialized support services and addressing stigma-related stress, such as “coming out” and experiences of discrimination and harassment. Focus group participants suggested that dedicated e-therapies for lesbians and gay men should be developed or general e-therapies be made more inclusive by using adaptive logic to deliver content appropriate for a user’s sexual identity.ConclusionsFindings from this study offer in-depth guidance for developing e-therapies that more effectively address mental health problems among lesbians and gay men.  相似文献   
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In the present work, modified embedded atom potential and large-scale molecular dynamics’ simulations were used to explore the effect of grain boundary (GB) segregated foreign interstitials on the deformation behavior of nanocrystalline (nc) iron. As a case study, carbon and nitrogen (about 2.5 at.%) were added to (nc) iron. The tensile test results showed that, at the onset of plasticity, grain boundary sliding mediated was dominated, whereas both dislocations and twinning were prevailing deformation mechanisms at high strain. Adding C/N into GBs reduces the free excess volume and consequently increases resistance to GB sliding. In agreement with experiments, the flow stress increased due to the presence of carbon or nitrogen and carbon had the stronger impact. Additionally, the simulation results revealed that GB reduction and suppressing GBs’ dislocation were the primary cause for GB strengthening. Moreover, we also found that the stress required for both intragranular dislocation and twinning nucleation were strongly dependent on the solute type.  相似文献   
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