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91.
The unique inborn hypertriglyceridemia seen in FLS (fatty liver Shionogi) mice was relieved by the administration of purified apolipoprotein (apo) C-II. Lipoprotein lipase (LPL) and its cofactor, apoC-II, play a pivotal role in VLDL metabolism. Therefore, we investigated the genetic background involved in this hypertriglyceridemia. Plasma levels of TG and total cholesterol as well as LPL activity were measured in male FLS mice and C57/BL6J mice. Agarose gel electrophoresis and fast protein liquid chromatography were used to analyze the lipoprotein profile. A cross experiment was done to determine the genetic background of hypertriglyceridemia observed in FLS mice. cDNA sequences of apoC-II and apoC-III of FLS mice were determined. Preα-lipoprotein was the predominant lipoprotein class in FLS mouse plasma. LPL activity remained in the range observed in C57/BL6J mice, and purified apoC-II transiently relieved FLS mice from hypertriglyceridemia. Preα-lipoproteinemia was inherited in an autosomal recessive manner. ApoC-III appeared to be a causal factor for this unique hypertriglyceridemia. Microsatellite analysis, however, revealed that the responsible chromosome was not 7; rather, apoC-III mapped onto chromosome 9. Therefore, we suggest apoC-III as a candidate causative factor for the hypertriglyceridemia observed in FLS mice because an excessive amount of apoC-III attenuates LPL activity in vivo and in vitro.  相似文献   
92.
Phosphotetradecavanadate (PV14) was dispersed on a silica gel chemically modified with a silane coupling agent (AnPS-SiO2) by an equilibrium adsorption method. The PV14 contents approximately correlated with the V(IV) spin contents by ESR. PV14 dispersed on AnPS-SiO2 resulted in a quite high selectivity for formaldehyde such as 97% in methanol oxidation.  相似文献   
93.
Although a loss-of-function mutation has been identified in familial Parkinson’s disease PARK7, the wild-type of DJ-1 is known to act as an oxidative stress sensor in neuronal cells. Recently, we identified UCP0045037 as a compound that bound to the reduced form of DJ-1 by in silico virtual screening. In this study, we determined the neuroprotective effects of UCP0045037 against focal cerebral ischemia-induced neurodegeneration in rats. Hydrogen peroxide-induced cell death was significantly inhibited by UCP0045037 in both rat mesencephalic dopaminergic neurons and human normal SH-SY5Y cells. In contrast, DJ-1-knockdown SH-SY5Y cells lost the protective activity of UCP0045037. These results suggest that UCP0045037 interacts with endogenous DJ-1 and produces a neuroprotective response.  相似文献   
94.
The pressure sensitive adhesive (PSA) properties of two samples of poly(vinyl ethylene-co-1,4-butadiene) (V-BR) (vinyl content: 47.4 and 60 wt%) blended with hydrogenated terpene resin (CLEARON P125) were measured on blend compositions having CLEARON P125 contents (by weight) of 10%, 30% and 50%. The maximum values of 180° peel adhesion, rolling ball tack and probe tack were observed with a V-BR/CLEARON P125 70/30 blend, whereas the maximum values of holding power were obtained with a 50/50 V-BR/CLEARON P125 blend. In these blends, the miscibility between V-BR and CLEARON P125 was confirmed by means of SEM, DSC and light scattering. The influences of surface tension and dynamic mechanical properties on PSA properties were investigated. The surface tension values were essentially the same in all the V-BR/CLEARON P125 blends. Minimum values of storage modulus G′ and loss modulus G″ at room temperature in V-BR/CLEARON P125 blends were obtained with a 70/30 blend. Thus, it is believed that in V-BR/CLEARON P125 blends, 180° peel adhesion and tack are related to the dynamic mechanical properties.  相似文献   
95.
96.
For the blends of acrylate copolymer [poly(2-ethylhexyl acrylate-co-acrylic acid); P(2EHA-AA)] with ultraviolet (UV) curable oligomer [urethane acrylate oligomer; UAO], pressure-sensitive adhesive (PSA) properties, such as peel adhesion, probe tack, and holding power were examined. The values of peel adhesion and probe tack of the P(2EHA-AA)/UAO blends were dramatically reduced by UV irradiation. On the other hand, all blends had a high holding power even if these blends were cured by UV irradiation. The mechanism of reduced PSA properties was investigated via dynamic mechanical properties, DSC, and dynamic contact angle (DCA). The peel adhesion decreased monotonically with increasing storage modulus, E', and loss modulus, E', for all non-UV and UV-cured blends. Since modulus values and glass transition temperatures, Tg, of these blends after UV irradiation were higher than those of these blends before UV irradiation, we judged that the reduced peel adhesion and probe tack values were caused by the modulus increase and the Tg increase due to UV irradiation. In other words, the ability of the deformation energy of UV-cured blends to influence the adhesive tests was reduced by the curing process. The DCAs of non-UV-cured blends were the same as those of UV-cured blends. We presumed that the segment mobility of the polymer chain on the surface did not contribute to the reduced peel adhesion and probe tack values.  相似文献   
97.
The relationship between the surface composition and the rate of solvent evaporation (R) in blend films of poly(vinylidene fluoride‐co‐hexafluoroacetone) (P(VDF‐HFA)) and poly(2‐ethylhexyl acrylate‐co‐acrylic acid‐co‐vinyl acetate) (P(2EHA‐AA‐VAc)) has been investigated. P(VDF‐HFA), a low‐surface tension component, was concentrated on the surface when R was relatively high. In contrast, when R was relatively low, P(2EHA‐AA‐VAc), a low‐density component, was concentrated on the surface. Therefore, it is speculated that the factors dominating surface enrichment in polymer blends were changed from surface tension differences to density differences between the components when R was decreased. In addition, the affinity between components and substrate strongly affects the dominant factors determining the surface composition. © 2001 Society of Chemical Industry  相似文献   
98.
介绍了影像领域 HDD、 CD、 DVD及 DVC等可换型封装存储介质的现状及发展方向,指出垂直磁记录方式又成为研究的热门课题。高密度化是存储介质的共同课题,其发展目标是 100 Gb/in2,还指出了影像信息存储领域存在的问题。  相似文献   
99.
A simple method of rotating an optical fiber bundle is presented to apply the random-pattern referencing scheme to hologram multiplexing. In the theoretical study, a dependence of the diffraction efficiency on the number of spatial frequencies in the reference pattern is estimated with the Bragg diffraction theory. In the experiment, hologram multiplexing is performed in which 30 holograms are recorded in a LiNbO3 crystal and are read out by rotating a fiber bundle. The result shows that this simple approach enables us to perform the hologram multiplexing and also contributes to the building of a compact optical setup.  相似文献   
100.
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