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121.
D-Glyceric acid (D-GA) calcium has been reported to accelerate ethanol oxidation in vivo in rats (Eriksson et al., Metabolism, 56, 895-898 (2007)). However, no other reports have shown that D-GA can reduce the harmful effects of ethanol. In this study, the effects of D-, L-, and DL-GA calcium on ethanol-dosed gastric cell viability were investigated using human gastric carcinoma cells (Kato III) and normal rat gastric mucosa cells (RGM1). Addition of 2% and 3 % ethanol to Kato III and RGM1 cells, respectively, decreased their cell viability by approximately 20-50 % after 24 or 72 h of cultivation. In 2 % ethanol-dosed Kato III cells cultivated for 24 h, addition of 0.002-20 μg/mL D- and L-GA calcium did not affect cell viability. Similarly, addition of less than 20 μg/mL DL-GA calcium did not affect cell viability. However, when 20 μg/mL DL-GA calcium was added, cell viability increased by 35.7 % after 72 h of incubation, compared to the viability of control cells without ethanol or GA. Addition of 20 μg/mL DL-GA calcium to 3 % ethanol-dosed RGM1 cells cultivated for 24 or 72 h also increased cell viability up to those observed in control cells. These results suggest that a racemic mixture of GA may have the strongest effect on enhancing the viability of ethanol-exposed cells.  相似文献   
122.
Previously, Le?ová et al. reported the isolation and identification of metabolite OR-1, showing antitrypsin activity, produced during fermentation by Penicillium funiculosum. The structure of OR-1 was a mixture of glyceric acid (GA), esterified with C(14)-C(18) fatty acids, and oleic acid (C18:1) as the most predominant fatty acid (Folia Microbiol. 46, 21-23, 2001). In this study, dioleoyl D-GA and dioleoyl L-GA were synthesized via diesterification with oleoyl chloride, and their antitrypsin activities were evaluated using both a disk diffusion method and spectral absorption measurements. The results show that both compounds and their equivalent mixtures possess antitrypsin activities; however, their IC(50) values (approximately 2 mM) are much higher than that of OR-1 (4.25 μM), suggesting that dioleoyl GA does not play a major role in the OR-1 antitrypsin activity.  相似文献   
123.
Because of the unclear conclusion of the repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) effects on the posterior electroencephalogram (EEG) alpha wave, this study is aimed at investigating these unclear effects. Transcranial stimulation effects are observed by analyzing a measured EEG at the occipital area between prestimulation and the poststimulation. The EEG alpha power and alpha coherence are calculated and analyzed in terms of the ratio between eyes closed and eyes open periods. The results reveal that alpha power ratio at the individual alpha frequency (IAF) significantly increases after the 1‐Hz rTMS and cathodal tDCS and slightly decreases after the anodal tDCS compared to the control and the sham conditions. The results also show that there is a significant difference between the inhibited and excited conditions. Similarities are observed in the patterns of the alpha coherence ratio and alpha power changes. The alpha coherence increases in the rTMS and cathodal tDCS conditions, and decreases in the anodal tDCS condition but these effects occur only when comparing across the hemispheres (O1–O2 and P3–P4). It can be summarized that the EEG alpha wave can be influenced by the transcranial stimulations. The rTMS and cathodal tDCS seem to facilitate the alpha activity and the anodal tDCS inhibits it. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
124.
In Japan, the lubricating oil used for the internal combustion engine of passenger cars is usually exchanged for fresh oil after running a distance in the range from 3,000 to 10,000 km. Refining of the used engine oil is very costly because friction-reducing additives containing sulfur, phosphorus, etc., are included in the oil. Therefore, wasted engine oil (used engine oil) is burned in many cases. This investigation was conducted to effectively re-use wasted engine oil without chemical refining. Performance of used engine oil as a gear-cutting oil was examined by conducting five kinds of experiments: (a) chemical analyses of the oils, (b) measurements of friction coefficients on the four-ball tester, (c) tool wear tests using a lathe, (d) tool life tests using a gear-cutting machine, and (e) accuracy and surface finish of the cut gears. In contrast to general expectations, longer tool lives were obtained when the used engine oils were used instead of a high-grade gear-cutting oil. The reason for this was discussed and it was concluded that used engine oil may be used as a high-performance gear-cutting oil if health risks for workers are removed.  相似文献   
125.
126.
Outline of the Product Composite Copper Clad Laminates are made from more than two kinds of materials using CEM-1 and CEM-3 as its main grades.  相似文献   
127.
For nonlinear thermal power plants whose dynamics vary with load demand, a load-dependent exponential ARX (Exp-ARX) model, which can effectively describe the nonlinear properties of the plants, is presented. The Exp-ARX model requires only off-line identification. Based on the model, a constrained multivariable generalized predictive control (CMGPC) strategy is designed and implemented in a simulation of 375 MW thermal power plants. This CMGPC algorithm does not resort to on-line parameter estimation and can more exactly predict the future outputs of the nonlinear plants, so it shows better reliability and control performance than the usual GPC algorithm.  相似文献   
128.
在窄缝流道内发生沸腾换热现象时,由于沸腾产生的汽泡受窄缝流道的限制,受压变形而消除了汽泡表面张力对传热的影响。因此对此现象进行基础性理论研究具有很重要的意义。本文在常压下用蒸馏水对窄缝间隙为 0.75mm的垂直环形流道,进行了流动沸腾传热实验研究。实验段的有效加热长度为 900mm,其加热方式为内外侧双面加热,实验的流量变化范围在 1.67× 10- 5~ 5.83× 10- 5m3/s。通过实验得到了在不同质量流速和热流密度下双面加热的窄缝流道中内外侧沸腾换热系数随干度变化的分布和特点。研究结果表明,由于在窄缝流道中存在着大量的运动聚合受压变形汽泡,因此使内外侧沸腾换热系数都很高 (可达 105W· m- 2· K- 1以上 )。  相似文献   
129.
1. IntroductionThe total performance of inverter power supplieshas improved drastically as a result of the development of colltrol methods, higher performance in semiconductors, and higher speed, higher integration, andlower cost in integrated circuits, making it possible touse the inverter drive method in a wide range of rotating machinery which requires smaller size and/or variable speed drives. In line with these trends, magneticloss under nonsinusoidal waveform excitation, including lower …  相似文献   
130.
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