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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   
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Although chronic lymphocytic leukaemia of B-cell type (B-CLL) is the most common form of leukaemia in the Western world, several questions about the biology of B-CLL remain to be clarified. To obtain a conceptual model for B-CLL, defined as a relentless accumulation of resting B-CLL cells, it is particularly relevant to ask which cell type is the normal counterpart of B-CLL; what is the site of proliferation; which signals are involved in the recruitment and induction of proliferation and which signals contribute to the survival of the B-CLL cells? The significance of the studies on B-CLL cellsin vitro for the interpretation of thein vivo situation may be questioned since they oversimplify the multiple and complex cellular interactions that occurin vivo. However, thein vitro studies have been instrumental in elucidating signals that may regulate growth, differentiation and survival of B-CLL cells. This knowledge, herein reviewed, can be used to put forward a hypothesis on B-CLL cell regulationin vivo.  相似文献   
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The importance of genetic factors in the etiology of non-Hodgkin lymphoma (NHL) is suggested by case-control and cohort studies. Most previous studies have been too small to estimate accurately risks of specific categories of lymphoproliferative malignancies in relatives of NHL cases or to quantify the contribution of NHL case characteristics to familial risk. We have overcome sample size limitations and potential recall bias by using large databases from Sweden and Denmark. Diagnoses of lymphoproliferative malignancies were compared in 70,006 first-degree relatives of 26,089 NHL cases (including 7,432 with subtype information) versus 161,352 first-degree relatives of 58,960 matched controls. Relatives of NHL cases were at significantly increased risk for NHL [relative risk (RR), 1.73; 95% confidence interval (95% CI), 1.39-2.15], Hodgkin lymphoma (RR, 1.41; 95% CI, 1.0-1.97), and nonsignificantly for chronic lymphocytic leukemia (CLL; RR, 1.31; 95% CI, 0.93-1.85). No increased risk was found for multiple myeloma among case relatives. Findings with respect to siblings compared with parents and offspring or with respect to age at diagnosis of proband were inconsistent. In both populations, relatives of cases with an aggressive NHL subtype were at substantially increased risk of NHL (combined RR, 3.56; 95% CI, 1.80-7.02). We conclude that NHL has an important familial component, which is shared with Hodgkin lymphoma and CLL. We estimate that the absolute lifetime risk for a first-degree relative of an NHL case to develop NHL is 3.6% (compared with a population risk of 2.1%) and higher if the index case had an aggressive subtype of NHL.  相似文献   
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The aim of this study was to evaluate the expression of activin: beta A and beta B subunit and follistatin in endometrium of women with implantation failure ( n = 10) and compare it with a fertile control group ( n = 7). Immunohistochemical staining intensity for follistatin in the endometrial glandular epithelium from women with implantation failure were significantly lower than that in control women ( P = 0.03). The decreased expression of follistatin in epithelial cells in the endometrium of women with implantation failure after in vitro fertilisation (IVF) may suggest that follistatin may play a role in the implantation process.  相似文献   
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Public health professionals work with a variety of information sources to carry out their everyday activities. In recent years, interactive computational tools have become deeply embedded in such activities. Unlike the early days of computational tool use, the potential of tools nowadays is not limited to simply providing access to information; rather, they can act as powerful mediators of human-information discourse, enabling rich interaction with public health information. If public health informatics tools are designed and used properly, they can facilitate, enhance, and support the performance of complex cognitive activities that are essential to public health informatics, such as problem solving, forecasting, sense-making, and planning. However, the effective design and evaluation of public health informatics tools requires an understanding of the cognitive and perceptual issues pertaining to how humans work and think with information to perform such activities. This paper draws on research that has examined some of the relevant issues, including interaction design, complex cognition, and visual representations, to offer some human-centered design and evaluation considerations for public health informatics tools.  相似文献   
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Rationale, aims and objectives Continuous positive airway pressure (CPAP) treatment of obstructive sleep apnea (OSA) has a low long‐term adherence. Educational interventions are few and sparsely described regarding content, pedagogical approach and participants' perceptions. The aim was to describe adherence to CPAP treatment, knowledge about OSA/CPAP, as well as OSA patients' perceptions of participating in a group‐based programme using problem‐based learning (PBL) for CPAP initiation. Educational programme The PBL programme incorporated elements from theories and models concerning motivation and habits. Tutorial groups consisting of four to eight patients met at six sessions during 6 months. Methods A sequential explanatory mixed method design was used on 25 strategically selected patients. Quantitative data regarding, clinical variables, OSA severity, CPAP use, and knowledge were collected at baseline, after 2 weeks and 6 months. Qualitative data regarding patients' perceptions of participation were collected after 6 months by semi‐structured interviews using a phenomenographic approach. Results 72% of the patients were adherent to CPAP treatment after 2 weeks and 6 months. All patients improved their baseline knowledge about OSA and CPAP after 2 weeks and sustained it after 6 months. Anxiety and fear, as well as difficulties and needs were motivational factors for participation. Patients described the difficulties of behavioural change, an awareness that improvements do not occur immediately, a realization of the importance of both technical and emotional support and the need for a healthier lifestyle. Conclusion and practice implications A group‐based programme using PBL seems to facilitate adaptive and developmental learning and result in acceptable CPAP adherence levels.  相似文献   
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