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71.
Effects of dietary lipids on daunomycin-induced nephropathy in mice: comparison between cod liver oil and soybean oil 总被引:3,自引:0,他引:3
Although it is well known that dietary lipids affect the course of glomerulonephritis in rats and humans, the precise mechanisms
involved have not been fully elucidated. The aim of this study was to investigate the effects of different types of dietary
lipids (fish oil and vegetable oil) on daunomycin (DM)-induced nephropathy in mice fed on soybean oil (SO) or cod liver oil
(CLO). Urinary protein excretion, serum albumin, creatinine, total cholesterol, and TG were measured, and glomerular histological
changes were evaluated. Antioxidant enzymes were also measured, along with the levels of lipid peroxide, GSH, thromboxane
(Tx) B2′ and 6-keto prostaglandin F1α in renal cortical tissue. Dietary CLO significantly reduced urinary albumin excretion and ameliorated the histological changes
induced by DM. The increase of tissue lipid peroxide levels seen in SO-fed mice was suppressed in CLO-fed mice, whereas CLO-fed
mice showed higher GSH levels than SO-fed mice throughout the experiment. In addition, renal tissue GSH peroxidase activity
was significantly higher at 72 h after DM injection in CLO-DM mice than in SO-DM mice. Both renal cortical TxB2 and 6-keto PGF1α levels were significantly lower in CLO-DM mice than in SO-DM mice. These results suggest that inhibition of oxidative damage
by dietary CLO played an important role in the prevention of DM nephropathy in this mouse model. The effect of CLO was closely
associated with the inhibition of Tx synthesis. 相似文献
72.
73.
Minoru Tsuda Setsuko Oikawa Akira Yokota Mitsuo Yabuta Wataru Kanai Ken-Ichi Kashiwagi Isamu Hijikata Hisashi Nakane 《Polymer Engineering and Science》1983,23(18):993-999
A dry developable negative working resist composition comprised of poly(methyl isopropenyl ketone) (PMIPK) and 4-methyl-2,6-di(4′-azido-benzylidene) cyclohexanone-1 was examined. The main photochemical product formed in the resist pattern was found to be a secondary amine which crosslinks PMIPK. Post-annealing forms a hydrogen-bonded product which shows a powerful electronic excitation energy quenching effect. The quencher is more powerful than the aromatic compound arising from the azide by post-annealing only. The residual resist thickness of the negative pattern is about 80 percent of the initial thickness of the coating in spite of all the azide compound remaining in the resist coating. The obtained dry developed resist pattern has a high dry etch resistance. Etchings of Si and SiO2 were performed by plasma and reactive ion etching, respectively. 相似文献
74.
The oxygen content of silicon nitride with 1 mol% Y2 O3 —Nd2 O3 additive was measured after firing to determine the compositional change during gas-pressure sintering. Oxygen content decreases from 2.5 to 0.94 wt% during firing for 4 h at 1900°C and 10-MPa pressure in N2 . This decrease in oxygen results from the release of SiO gas generated by a thermaldecomposition reaction between Si3 N4 and SiO2 . The resultant sintered silicon nitride material contains less than 1 wt% oxygen. 相似文献
75.
固态直线变压器驱动源(LTD)是新型的脉冲功率电路方法之一.其工作原理基于大量功率半导体器件的同步控制,因此它在电路结构和工作特性方面与传统的脉冲功率电源有很大不同.在此通过实验,首先验证了LTD的基本工作原理,进而试制了一台采用650个功率MOSFET的LTD系统.实验结果分别给出了超过20 kV的最高输出电压和超过3.2 kA的最高输出电流,上升时间(10%~90%)小于20 ns.在此基础上还采用少量的模块验证了双极性LTD的可行性.实验结果同时也显示了开关的导通电阻对LTD输出参数的影响和由此带来的技术问题. 相似文献
76.
77.
Naoji Shiroma Ryo Miyauchi Akira Nagafusa Youhei Haga Fumitoshi Matsuno 《Advanced Robotics》2015,29(3):149-163
In robot teleoperation, a robot works as a physical agent at a remote site for a robot operator. There are mainly two tasks in robot teleoperation using camera images: environment recognition using visual information and robot control according to the recognition. In this paper, we propose a gaze direction based vehicle teleoperation method with an omnidirectional image stabilization and an automatic body rotation control. In the proposed method, we manage above two tasks in the same manner that are usually treated separately. This method is an intuitive vehicle teleoperation method where an operator do not need to have concern about vehicle body orientations and can absorb differences of vehicle driving mechanisms. That is, this method frees an operator from being bothered from controlling a vehicle and the operator can concentrate on where he/she intends to go. This method mainly consists of two technologies: an omnidirectional image stabilization technology and automatic body rotation control. The conducted experiments show effectiveness of the proposed method. 相似文献
78.
In this paper null controllability with vanishing energy for discrete-time systems is considered. As in the case of continuous time systems necessary and sufficient conditions in terms of an algebraic Riccati equation are given. Then necessary and sufficient conditions involving the eigenvalues of the state matrix are given. Reachability and controllability with vanishing energy are also considered and necessary and sufficient conditions for them are given. Finally applications to sampled-data systems, systems with impulse control and periodic systems are discussed. 相似文献
79.
Hiroki Kikuchi Shigeki Hashimoto Shinichiro Tajiri Tsuneo Hayashi Yutaka Sugawara Michio Oka Yoshiyuki Akiyama Akira Nakamura Naoya Eguchi 《Journal of the Society for Information Display》2009,17(3):263-269
Abstract— A high‐pixel‐rate, high‐contrast (30,000:1) wide‐color‐gamut grating‐light‐valve laser projector is reported. A new optical engine enabling high‐frame‐rate (240 Hz) scan projection is employed. Panoramic wide‐angle‐scan projection with a 64:9 aspect ratio was also developed. Speckle noise is eliminated using a simple but highly efficient technique. The optical throughput efficiency of the grating‐light‐valve laser projector is reviewed. 相似文献
80.
Kiyoshi Itatani Takayasu Kubozono F. Scott Howell Akira Kishioka Makio Kinoshita 《Journal of Materials Science》1995,30(5):1196-1202
The sinterability of mullite (3Al2O3·2SiO2) powder prepared by chemical vapour deposition was examined to improve the conditions for fabricating dense mullite ceramics. The starting powder contained not only mullite, but also a small amount of -Al2O3 (Al-Si spinel) and amorphous material. Although the compressed powder was fired at a temperature between 1550 and 1700 °C for 1, 3 and 5 h, the relative densities of the sintered compacts were limited to 90%: (i) due to the creation of pores/microcracks during the solid state reaction (1100–1350 °C), and (ii) due to restriction on the rearrangement of grains because the amount of liquid phase (1550–1700 °C) was insufficient. Calcination of the starting powder was effective for preparation of easily sinterable powder with homogeneous composition. When the compact formed by compressing the calcined powder at 1400 °C for 1 h was fired at 1650 °C for 3 h, the relative density was raised up to 97.2%; moreover, mullite was the only phase detected from the sintered compact. The sintered compact was composed of polyhedral grains with sizes of 1–2 m and elongated grains with long axes of 6 m. 相似文献