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Background  

Ankylosing spondylitis is a chronic inflammatory rheumatic disorder which usually begins in early adulthood. The diagnosis is often delayed by many years. MR imaging has become the preferred imaging method for detection of early inflammation of the axial skeleton in ankylosing spondylitis.  相似文献   
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The occupational health nurse can play an important role in supporting employees with CKD and ESRD by recognizing risk factors such as diabetes and hypertension associated with CKD. The occupational health nurse should encourage compliance with treatment regimens that retard or delay progression of kidney disease into the next stage, especially blood pressure and glucose control. When employees are in need of diagnostic testing, the occupational health nurse can describe the testing procedures such as laboratory values, ultrasounds, and biopsies, and explain the five stages of CKD. The occupational health nurse can assist employees in Stage 4 or 5 CKD in deciding on a treatment option modality that best suits their individual lifestyles, after they have seen a nephrologist and kidney patient educator. In addition, the occupational health nurse can guide employees with difficult lifestyle changes and provide support during the adjustment process. The occupational health nurse also can play a key role in facilitating and coordinating those changes with the renal social worker. Together they can explore available resources, such as the NKF, the American Association of Kidney Patients, and kidneydirections.com. See the Sidebar on pages 295 to 296 for other available resources. Kidney disease can be a devastating diagnosis. Support and education are key to a successful lifestyle transition. Employees who have CKD and work with an occupational health nurse who is informed about their disease and its stages of progression can benefit from educational processes that create informed choices to delay or retard the progression of their renal disease.  相似文献   
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目的:研究低氧时小鼠肺组织中低氧诱导因子-1α(HIF-k)表达的变化。方法:实验用雄性小鼠,低氧仓浓度分别为10%、7%、5%。用免疫荧光组织化学技术及共聚焦显微术,检测小鼠在低氧条件下肺组织中HIF-1α表达的变化。结果:正常组小鼠肺组织HIF-1α无表达,低氧组HIF-1α表达增加,且随低氧时间的延长及低氧强度的增加而增强。结论:低氧可诱导小鼠肺组织中HIF-1α的表达增强,(HIF-k)可能参与肺组织细胞凋亡的发生。  相似文献   
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To describe the relaxed expiration by a two-compartment model, we introduced a gas/energy transfer between the lung compartment (V1) and a second one (V2). If V2 were a real volume, the rate-constants (i.e. the flow/volume ratios) of the compartments would describe a real gas-exchange. Alternatively, if a viscoelastic behaviour of the lung or an energy-exchange between compartments was simulated, V2 would become a "pseudo-volume". We studied nine mechanically ventilated subjects. Changes in volume were transduced by respiratory inductive plethysmography. The rate-constants were assumed (together with the initial volumes of the compartments) as parameters to fit the total volume [V1(t)+V2(t)]. Once the best fitting was performed using these "physiological" parameters, the system was directly identified and the compartments were independently analysed. The time profile of the second compartment showed a maximum that depended on the value of the rate-constants. Appropriate tests confirmed the reliability of our procedure. In conclusion, our analysis demonstrated that the energy/volume of the second compartment may increase at the beginning of expiration and then decrease, showing a maximum, even though the total curve can only be a decreasing one. In other words, the slowing down of the curve representing expiratory volume is due not only to the longer emptying of the second compartment, but also to the interaction between the two compartments. As presently proposed, this interaction can be represented by either a gas exchange between two actual volumes, or a mechanical energy transfer between the lung and the tissue compartment.  相似文献   
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