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排序方式: 共有1193条查询结果,搜索用时 634 毫秒
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K Hisatomi N Hayashida E Tayama M Ohashi T Isomura K Kosuga K Oishi 《Canadian Metallurgical Quarterly》1993,94(8):791-795
Glucagon has been demonstrated to stimulate the uptake of bile acid in isolated rat hepatocytes (Am. J. Physiol., 249, G427 (1985)). In the present study, we determined the influence of glucagon on the hepatic transport of a bile acid, taurocholate (TCA), in isolated rat livers. A single-pass perfusion and a rapid-injection, multiple indicator dilution method were employed. The hepatic availability at steady-state was 0.04. With the presence of glucagon in the perfusate (from 10(-9) to 10(-7) M), the bile flow rate was stimulated by 30%, while hepatic availability was decreased from 0.04 to 0.02 with a stepwise increase in glucagon concentration. Thirty min after the infusion of glucagon (300 nM), [3H]TCA and [14C]inulin were injected in a bolus state into the portal vein, and the outflow was collected at 1.0 s intervals over 30 s. Glucagon decreased the instantaneous hepatic availability by 50% compared to the control level, and was thus compatible with the steady-state experiments. In the control experiment, the influx clearance (PSinf) was 20 times higher than the efflux clearance (PSeff). Glucagon (300 nM) in the perfusate enhanced PSinf by 50% of the control, whereas sequestration clearance (CLseq) and the biliary excretion rate constant remained unchanged. PSeff was stimulated to 2 times the control, but still remained much smaller than CLseq. Based on the comparison of PSinf, PSeff and CLseq, the rate-determining process of TCA hepatic elimination was the influx process in both the presence and absence of glucagon. Taken together, the enhancement of the influx process was responsible for the decrease in TCA hepatic availability caused by glucagon.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Hideaki Katayama Tsutomu Tawa Shinzaburo Ito Masahide Yamamoto Yoshio Wada 《Polymer Bulletin》1992,29(3-4):365-367
Summary The effect of side chain length on intramolecular triplet energy migration of naphthalene containing polymers was investigated by a delayed fluorescence (DF) spectroscopy for the solid solution of the polymers. The degree of triplet energy migration depends strongly on whether the chromophores are directly attached to the main chain or not. 相似文献
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Bhupesh C. Roy Motonobu Goto & Tsutomu Hirose 《International Journal of Food Science & Technology》1996,31(2):137-141
Tomato seed oil was extracted with supercritical carbon dioxide in a semibatch-flow extractor within the temperature range 313–343 K and the pressure range 10.8–24.5MPa. The extraction rates increased with pressure, but decreased with temperature increase because of the variation in solvent density and resultant differences in oil solubility. The fatty acid composition of the extracted oil was similar to that of soybean oil. 相似文献
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Oishi Shigehiro; Diener Ed; Choi Dong-Won; Kim-Prieto Chu; Choi Incheol 《Canadian Metallurgical Quarterly》2007,93(4):685
The authors examined cultural and individual differences in the relation between daily events and daily satisfaction. In a preliminary study, they established cross-cultural equivalence of 50 daily events. In the main study, participants in the United States, Korea, and Japan completed daily surveys on the 50 events and daily satisfaction for 21 days. The multilevel random coefficient model analyses showed that (a) the within-person association between positive events and daily satisfaction was significantly stronger among Asian American, Korean, and Japanese participants than among European American participants and (b) the within-person association between positive events and daily satisfaction was significantly weaker among individuals high in global life satisfaction than among those low in global life satisfaction. The findings demonstrate a weaker effect of positive events on daily well-being among individuals and cultures high in global well-being. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Tsutomu Takeichi Yuki Saito Tarek Agag Hiroyuki Muto Takehiro Kawauchi 《Polymer》2008,49(5):1173-1179
Two series of high-performance polymer alloys were prepared by mixing typical benzoxine monomers, 3-phenyl-3,4-dihydro-2H-1,3-benzoxazine (P-a) or 6,6-(1-methylethyliden)-bis-(3,4-dihydro-3-phenyl-2H-1,3-benzoxazine) (B-a), with a typical bismaleimide, 4,4-bismaleimidodiphenyl methane by various ratios followed by thermal treatment up to 240 °C. DSC and IR of the alloys were examined to follow the curing reaction. These analyses showed that the obtained polymer alloys are AB co-cross-linked polymer networks through the formation of ether linkage between the hydroxyl group of polybenoxazine and the double bond of bismaleimide. Viscoelastic analysis and softening temperature measurement revealed that the polymer alloys have much higher glass transition temperatures than those of each homopolymer. The thermal stability also increased with the increase of bismaleimide content as evidenced by TGA. 相似文献
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Makoto Ishiguro Katsufumi Ohmuro Yukito Saitoh Yuuta Takahashi Jun Watanabe Tsutomu Arai Yoji Ito Keiji Mihayashi 《Journal of the Society for Information Display》2012,20(11):598-603
We have successfully developed a quarter‐wave retardation film (QWF) for wide viewing angle 3D liquid crystal displays (3D‐LCDs) that provides high luminance, low crosstalk, low color change, and low head‐tilt‐angle dependency. It was found that the out‐of‐plane retardation (Rth) of the QWF in the LCD needs to be close to 0 nm in order to improve the 3D display properties at an off‐axis position and that the in‐plane retardation (Re) needs to be adjusted from 120 to 130 nm to achieve low color change with head tilting. We adopted a coating process for making our QWF because of its potential for retardation control. 3D‐LCDs with this QWF whose Rth was nearly zero had high performance and allowed off‐axis other than on‐axis. 相似文献
10.
Takeyuki Suzuki Tsutomu Yamazaki Hiroshi Yoshioka Kuniyuki Hikichi 《Journal of Materials Science》1988,23(1):145-149
Amorphous SnOx films were deposited by ion-beam sputtering on sintered alumina substrates. Amorphous film sensors were prepared by annealing the films at 300° C for 2 h in air. The thickness dependence of resistivity and hydrogen gas sensitivity were measured at 150° C over the thickness range 1 to 700 nm. A resistivity maximum was observed in ultrathin films. Resistivity increased by three orders of magnitude with increasing film thickness from 0.9 to 7.4 nm and then decreased by five orders of magnitude from 7.4 to 35 nm. Ultrathin film sensors showed sensitivity maxima around a thickness of 10 nm. Sensitivity and resistivity of ultrathin films were significantly influenced by the thermal expansion coefficient and the surface state of the substrate. 相似文献