The effects of B2O3 addition on both the sintering behavior and microwave dielectric properties of CaO-B2O3-SiO2 （CBS） glass ceramics were investigated by Fourier transform infrared spectroscopy （FTIR）, X-ray diff...The effects of B2O3 addition on both the sintering behavior and microwave dielectric properties of CaO-B2O3-SiO2 （CBS） glass ceramics were investigated by Fourier transform infrared spectroscopy （FTIR）, X-ray diffractometry （XRD） and scanning electron microscopy （SEM）. The results show that the increasing amount of B203 causes the increase of the contents of [BO3], [BO4] and [SiO4], which deduces the increase of CaB204 and a-SiO2 and the decrease of CaSiO3 correspondingly. No new phase is observed throughout the entire experiments. A bulk density of 2.54 g/cm3, a thermal expansion coefficient value of 11.95× 10-6 ℃-1 （20-500℃）, a dielectric constant er value of 6.42 and a dielectric loss tanδ value of 0.000 9 （measured at 9.7 GHz） are obtained for CBS glass ceramics containing 35%-B203 （mass fraction） sintered at 850 ℃ for 15 min.展开更多
The major clinical disturbances in Parkinson’s disease (PD) are consequence of dopamine depletion in the neostriatum, due to degeneration of dopaminergic neurons. The aim of the present study was to determine whether...The major clinical disturbances in Parkinson’s disease (PD) are consequence of dopamine depletion in the neostriatum, due to degeneration of dopaminergic neurons. The aim of the present study was to determine whether oxidative stress (OS) occurs during the clinical course of Parkinson’s disease and to evaluate the influence of therapy on the levels of some important final products of oxidation of lipids, proteins and nucleic acids in PD patients with drug therapy. For this purpose, we investigated the levels of malondialdehid (MDA), protein carbonyl content (PCC) and 8-hydroxy-2’-deoxyguanosine quantity (8-OHdG) in PD patients with and without drug therapy. The observed changes in MDA levels, PCC and 8-OHdG quantity in blood of untreated PD patients, suggested impaired antioxidant status and presence of oxidative stress in Parkinson disease. After treatment with Madopar, the elevation in by-products significantly progresses. Our results demonstrate that administration of Madopar causes in greater degree oxidative stress than that induced by Parkinson disease, by itself.展开更多
基金Project(2007AA03Z0455) supported by the National High-Technology Research and Development Program of ChinaProject(BE2009168) supported by the Natural Science Foundation of Jiangsu Province in ChinaProject supported by the Priority Academic Program Development of Jiangsu Higher Education Institution,China
文摘The effects of B2O3 addition on both the sintering behavior and microwave dielectric properties of CaO-B2O3-SiO2 （CBS） glass ceramics were investigated by Fourier transform infrared spectroscopy （FTIR）, X-ray diffractometry （XRD） and scanning electron microscopy （SEM）. The results show that the increasing amount of B203 causes the increase of the contents of [BO3], [BO4] and [SiO4], which deduces the increase of CaB204 and a-SiO2 and the decrease of CaSiO3 correspondingly. No new phase is observed throughout the entire experiments. A bulk density of 2.54 g/cm3, a thermal expansion coefficient value of 11.95× 10-6 ℃-1 （20-500℃）, a dielectric constant er value of 6.42 and a dielectric loss tanδ value of 0.000 9 （measured at 9.7 GHz） are obtained for CBS glass ceramics containing 35%-B203 （mass fraction） sintered at 850 ℃ for 15 min.
文摘The major clinical disturbances in Parkinson’s disease (PD) are consequence of dopamine depletion in the neostriatum, due to degeneration of dopaminergic neurons. The aim of the present study was to determine whether oxidative stress (OS) occurs during the clinical course of Parkinson’s disease and to evaluate the influence of therapy on the levels of some important final products of oxidation of lipids, proteins and nucleic acids in PD patients with drug therapy. For this purpose, we investigated the levels of malondialdehid (MDA), protein carbonyl content (PCC) and 8-hydroxy-2’-deoxyguanosine quantity (8-OHdG) in PD patients with and without drug therapy. The observed changes in MDA levels, PCC and 8-OHdG quantity in blood of untreated PD patients, suggested impaired antioxidant status and presence of oxidative stress in Parkinson disease. After treatment with Madopar, the elevation in by-products significantly progresses. Our results demonstrate that administration of Madopar causes in greater degree oxidative stress than that induced by Parkinson disease, by itself.
