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21.
Atherosclerotic cardiovascular disease is an important cause of mortality and morbidity in hemodialysis patients. Iron accumulation in arterial wall macrophages is increased in atherosclerotic lesions. Hepcidin is a key hepatic hormone regulating iron balance. It inhibits iron release from macrophages and iron absorption from enterocytes by binding and inactivating the cellular iron exporter ferroportin. The aim of this study is to investigate the relation of hepcidin‐25, iron parameters, and atherosclerosis measured by carotid intima media thickness (CIMT) in hemodialysis patients. Eighty‐two hemodialysis patients were enrolled in this cross‐sectional study. Predialysis blood samples were centrifuged at 1500 g and 4°C for 10 minutes and stored at ?80°C for the measurement of hepcidin‐25. DRG hepcidin enzyme‐linked immunosorbent assay kit was used for the measurement of hepcidin‐25. Ultrasonographical B‐mode imaging of bilateral carotid arteries was performed with a high‐resolution real‐time ultrasonography (Mindray DC7). Mean age of the study population was 57.90 ± 16.08 years and 43.9% were men. Total study population was grouped into two according to median value of hepcidin‐25. There was no difference between groups with respect to age, dialysis vintage, and C‐reactive protein. CIMT was found to be statistically significantly higher in low hepcidin‐25 group. In correlation analysis, CIMT was found to be correlated with age (P < 0.01, R = 0.33) and hepcidin‐25 (P < 0.01, R = 0.46). In linear regression analysis, age (β = 0.31) and hepcidin‐25 (β = 0.44) were found to be the determinants of CIMT in hemodialysis patients. Our results implicate that hepcidin may take part in pathophysiology of atherosclerosis and cardiovascular disease in hemodialysis patients.  相似文献   
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Stimuli‐responsive optical etalons are an exciting class of next‐generation sensors because they are scalable, cost‐effective and offer tunability of their optical response across the entire UV–vis–NIR wavelength range. In this study, double‐network cellulose hydrogels are used as a soft, responsive medium and are incorporated into Fabry–Pérot optical etalons. The thin cellulose hydrogel layer can be solution processed. The hygroscopic hydrogel undergoes both refractive index and thickness changes in response to changes in humidity. This leads to strong changes in reflection due to optical interference within the metal–insulator–metal (MIM) cavity. The response can be optimized by adjusting the chemical crosslinker ratio. These flexible MIM structures provide a robust platform for optically based chemical sensors.  相似文献   
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The grain structure of vapor-deposited CdS and Cd1?xZnxS films was analyzed using standard metallographic techniques and found to be columnar. Columnar grains of submicron diameter grow initially normal to the substrate surface. During further film growth they tilt towards the source and grow in size as a result of the elimination of less favorably oriented grains. An appreciable number of grain boundaries were low energy subgrain boundaries. Quantitative analysis of the grain size on the film surface showed that the average grain diameter is thermally activated and that at low temperatures the grain structure is “bimodal”. The bimodal structure was more common in Cd1?xZnxS films. It is suggested that grain boundary motion plays a role in the development of the grain structure in these films. Possible effects of the observed microstructure on the performance of Cu2S/Cd1?xZnxS solar cells are discussed.  相似文献   
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The present study focused on dyeing, fastness, cytotoxic properties, and phenolic constituents of various types of fabrics including viscose, cotton, wool, and polyester-viscose blended fabrics with different parts of Anthemis tinctoria var. tinctoria. Comparative study was carried out between ethanol and aqueous extracts of stem, flower, and root of the plant in terms of phenolic constituents, cytotoxic activity, and dyeing properties. It was found that the quantity of phenolic constituents of ethanol and aqueous extracts was quite different. All parts of the plant extract show 0% cytotoxicity except ethanol extract of the root. All the extracts exhibit better cytotoxic activity than the standard cancer drug 5-Florouracil. Ethanol and water extracts of A. tinctoria var. tinctoria plant were used to dye fabrics, but only the water extract displayed dyeing properties. Best color strength value (K/S = 9.19) was obtained with aqueous extract of the stem in the presence of alum mordant for cotton fabrics.  相似文献   
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The aim of the study is to investigate the optimum dyeing conditions for wool and cotton fabrics with the nettle (Urtica dioica L.) extract. For this purpose, the leaves of the nettle were extracted with distilled water by using Soxhlet apparatus. Wool and cotton fabrics were pretreated with artificial animal urine system (AAUS) including NH3 (3%, v/v), CaC2O4 (3%, m/v), and urea (3%, m/v) before dyeing processes in order to improve the fastness properties of the dyed samples. The best dyeing conditions were evaluated in terms of color strength. The results reveal that the nettle leaves shall probably be an important raw material especially for dyeing of wool fibers.  相似文献   
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Satti RP  Kolhe PS  Olcmen S  Agrawal AK 《Applied optics》2007,46(15):2954-2962
Recent interest in small-scale flow devices has created the need for miniature instruments capable of measuring scalar flow properties with high spatial resolution. We present a miniature rainbow schlieren deflectometry system to nonintrusively obtain quantitative species concentration and temperature data across the whole field. The optical layout of the miniature system is similar to that of a macroscale system, although the field of view is smaller by an order of magnitude. Employing achromatic lenses and a CCD array together with a camera lens and extension tubes, we achieved spatial resolution down to 4 mum. Quantitative measurements required a careful evaluation of the optical components. The capability of the system is demonstrated by obtaining concentration measurements in a helium microjet (diameter, d=650 microm) and temperature and concentration measurements in a hydrogen jet diffusion flame from a microinjector (d=50 microm). Further, the flow field of underexpanded nitrogen jets is visualized to reveal details of the shock structures existing downstream of the jet exit.  相似文献   
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