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排序方式: 共有479条查询结果,搜索用时 15 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
3.
An equation of state for 1,1-difluoroethane (HFC 152a, CH3CHF2) has been developed on the basis of reliable experimental data including PVT, liquid Cp, and saturated-liquid-density data measured by our group. It is a non-dimensionalized virial equation whose functional form is the same as that originally developed for 1,1,1,2-tetrafluoroethane (HFC 134a) in our group. The effective range is for pressures up to 15 MPa, temperatures from 230 to 450 K, and densities to 1000 kg m−3. The equation represents reliable PVT measurements within ± 1% in pressure for the superheated vapour and supercritical fluid, while within ±0.5% in density for the compressed liquid. In addition, it should be noted that the equation represents the other essential thermodynamic properties including vapour pressures, saturated-liquid/ vapour densities, isobaric/isochoric specific heats and sound velocity in both the liquid and gaseous phase of HFC 152a. 相似文献
4.
Tetsuya Suemitsu Yoshino K. Fukai Hiroki Sugiyama Kazuo Watanabe Haruki Yokoyama 《Microelectronics Reliability》2002,42(1):47-52
The reliability of InP-based HEMTs is studied, focussing on how it is affected by the doped layer material and gate recess structure. Bias-and-temperature stress tests reveal that fluorine-induced donor passivation in the recess region, formed adjacent to the gate electrode, causes the source resistance (Rs) to increase at large drain bias voltages. The increase in Rs can be prevented by using InP or InAlP as the carrier supply layer material instead of InAlAs. On the other hand, the increase in the drain resistance (Rd) does not depend on the material of the carrier supply layer, which suggests that a mechanism different from that in the case of Rs should be considered. It is also found that a deep gate recess suppresses the increase in Rd after long-term stressing. 相似文献
5.
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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When West meets East: Contributions of Eastern traditions to the future of psychotherapy. 总被引:1,自引:0,他引:1
Bankart C. Peter; Koshikawa Fusako; Nedate Kaneo; Haruki Yutaka 《Canadian Metallurgical Quarterly》1992,29(1):141
Discusses 2 interrelated traditions as they are reflected in contemporary and traditional approaches to psychotherapy in Japan. One uses various meditational and self-focusing instructional sets whose common goal is to facilitate the slowing down, deepening, and clearer focusing of sensory and interpersonal awareness. The 2nd tradition focuses on physical self-regulation and autonomic self-control through exercises that foster enhanced voluntary control over physical states and processes. Eastern psychology offers a set of practices that help the individual overcome the inherent selfishness of his/her isolated experience. The goals of such work include recognition of gratitude to important people in the client's life, rediscovery of the joy of meaningful work, and the experience of a unifying cosmic consciousness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Kunio Mori Wataru Ibashi Hidetoshi Hirahara Yoshiyuki Oishi Masanari Katayama 《应用聚合物科学杂志》1995,58(13):2451-2458
2-Dibutylamino-1,3,5-triazine-4,6-dithiol (DB) and a mixture of DB and triallylisocyanurate (TAIC) were used as a lubricant during steel wire drawing due to a dry process. DB gave a polymer film with 180 nm in thickness to wire surfaces during the wire drawing. The polymer film had a disulfide structure on the backbone and contained a small amount of DB monomer and olygomer. Molecular weight and polymer weight increased with the drawing rate. The mixture of DB and TAIC gave mainly a three-dimensional polymer film with 225 nm in thickness to wire surfaces during drawing. The polymer film insoluble in THF had mono and disulfide structures and contained a small amount of linear polymer, DB, and TAIC. Such tribological polymerizations are estimated as follows: DB produces dithiyl radicals on a nascent surface formed during drawing and in the presence of oxygen and heat. The dithiyl radicals were polymerized by coupling with each other to give disulfide bonds or added to allyl groups in TAIC to give monosulfide bonds. It is concluded that this technique should be possible to use for unifying metal processing and surface treatment. © 1995 John Wiley & Sons, Inc. 相似文献
9.
In order to develop an energy-saving copper recycling process from wastes, electrochemical measurements were conducted in ammoniacal alkaline solutions containing Cu(I) ions and an ammonium salt of sulfate, chloride or nitrate. The results of each system were then compared. The polarization measurements suggested that the voltage required for the electrode process is lower in the chloride and nitrate systems than that in the sulfate system. The cathode current efficiency during the copper electrodeposition varied from 39 to 97% and increased with current density in the chloride and sulfate systems. In the nitrate system, the lowest cathode current efficiency of 30% was observed because of nitrate ion reduction. Based on these results, the power consumption required for the electrowinning stage of the copper recycling process was calculated. Among these three systems, the chloride system showed the lowest power consumption of 500 kWh t−1 at the current density of 200 A m−2, which is about 25% of the conventional copper electrowinning process from a copper sulfate-sulfuric acid solution. 相似文献
10.
Gallium activity in the B2 phase regions of both binary Co–Ga and ternary Co–Ga–Sb systems was measured by EMF method with stabilized zirconia solid electrolyte The temperature range was 1073–1273 K and Sb concentrations were 1, 2 and 3 mol fractions. Ga activity at 1173 and 1273 K increases sharply in Ga rich region and the addition of Sb to the CoGa phase increases Ga activity. Activity change corresponds to the lattice parameter change with Sb addition to the CoGa phase. 相似文献