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PURPOSE: To identify relationships between the obstructive defects of pulmonary sarcoidosis and the computed tomographic (CT) patterns of disease. MATERIAL AND METHODS: CT scans obtained in 45 patients were scored semiquantitatively for extent of five CT patterns, and the functional importance of each pattern was evaluated. RESULTS: The most prevalent CT patterns were decreased attenuation (n = 40), a reticular pattern (n = 37), and a nodular pattern (n = 36). At univariate and multivariate analyses, a reticular pattern was the main determinant of functional impairment, particularly airflow obstruction. The extent of a reticular pattern was independently associated with airflow obstruction, as shown by the inverse relationships with the forced expiratory volume in 1 second (FEV1) (P < .001), FEV1-forced vital capacity ratio (P < .01), maximum expiratory flow at 25% above residual volume (P < .001), and maximum expiratory flow at 50% above residual volume (P < .001) and the positive relationship with the residual volume-total lung capacity ratio (P < .001). CONCLUSION: In sarcoidosis, CT features compatible with small airways disease are common but contribute little to airflow obstruction, particularly in more advanced disease, which is characterized by an extensive reticular pattern. A reticular pattern at CT is the major morphologic association of airflow obstruction.  相似文献   
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The reproducibility, variability, and reliability of a simple aquatic-terrtestrial model ecosystem experiment was tested with p,p'-DDT. The variation among the model replicates as well as within the units was studied by using hierarchal analysis of variance. the complete budget of the chemical was calculated and a theoretical transport model was constructed. The degradation and accumulation of DDT was followed by gas chromatographic residue analysis, which showed good reproducibility of the experimental design. The degradation of DDT in the model was similar to that found in the field, but the determination of concentration factors was questionable. The material balance tables revealed that the soil and bottom substrates were the main contributors, which regulated the fate of the chemical in the model. The usefulness of the model is presented in this report.  相似文献   
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The term "diuretics" describes a concerning pharmacological action and side effects heterogeneous class of drugs. The special advantage of using diuretics includes reducing edema and expanded plasma volume often associated with hypertension and cardiovascular disease. Diuretics are one of the 5 major classes of antihypertensive agents recommended for the initial drug therapy of hypertension. However, currently treatment of hypertension with diuretics is controversial, because of potentially adverse effects on the cardiovascular risk profile, including deterioration in glucose control especially in patients with impaired glucose tolerance. Additionally there is concern about excess mortality associated with diuretic therapy and diabetes mellitus. The metabolic side effects on glucose metabolism and lipid profile are related to the type of diuretic and its dosage. The adverse effects of thiazides on insulin action, glycemia and lipid profile are dose dependent and can be minimized by using low doses. In contrast, indapamide seems not to alter glucose metabolism and lipid profile. The choice of diuretic depends on concomitant disease. In patients with nephropathy potassium sparing agents should not be used, however furosemid can be used even in high doses. Beside focus on indication of diuretics in patients with diabetes and their metabolic side effects treatment of therapy resistant hypertension in these patients are discussed in this review.  相似文献   
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Titanium and its alloys are widely used in load-bearing bioinert implants. Bioactive glasses (BAGs) form a chemical bond with bone, but they are not suitable for load-bearing applications. Creating a BAG coating on a titanium implant could combine the best properties of both materials. The results tend to be poor when conventional firing methods are applied to coat titanium with BAG. A local application of heat to melt the glass can be achieved by a CO2 laser. A new method is introduced to create BAG coatings on titanium locally in a controlled manner, with a focused CO2 laser beam. The coatings produced by this method precipitate calcium phosphate in vitro. Processing parameters (number of coated layers, laser power, and processing atmosphere) providing a firm attachment of the glass and good in vitro bioactivity were identified. XRD analysis showed no crystallisation of the glass due to processing with the laser. EDXA indicated the formation of a calcium phosphate layer, which FTIR suggested to be a hydroxyapatite. The results show CO2 laser processing to be a promising technique for the manufacture of 30-40 microm BAG coatings on titanium.  相似文献   
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经缩尺比例后,大跨度悬索桥模型的构件一般变得很细小,尺寸大的传感器无法或不宜安装在结构模型上,尤其是需作动力试验的模型,附加大量传感器及电缆线的质量、刚度和阻尼会严重影响试验的结果.为解决此问题,该文采用细柔的裸光纤光栅测量直径仅0.5mm细钢丝吊索及其他细小构件的应变.为获得光纤所测应变的传递函数,研制了激振用的光纤...  相似文献   
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