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排序方式: 共有921条查询结果,搜索用时 15 毫秒
61.
Reo Etani Takahiro Kataoka Yuichi Nishiyama Yuji Takata 《Journal of Nuclear Science and Technology》2013,50(12):1512-1518
It has been reported that radon inhalation activates antioxidative functions in liver and has an antioxidative effect against hepatopathy similar to that of the antioxidative effects of ascorbic acid (VC) or α-tocopherol (VE). In this study, we examined the combined effects of radon inhalation and antioxidant vitamin administration on acute alcohol-induced hepatopathy in mice. ICR mice were subjected to intraperitoneal (i.p.) administration of alcohol after pretreating with air only (sham) or radon at a concentration of approximately 2000 Bq/m3 for 24 hours and i.p. administration of VC (300 mg/kg body weight) or VE (300 mg/kg body weight). In mice injected with alcohol, the combined radon and antioxidant vitamins treatment significantly decreased the activities of glutamic oxaloacetic transaminase in serum compared to not only the alcohol-administered group (sham group), but also the radon inhalation with alcohol administration group or the vitamin and alcohol administration group. In addition, radon inhalation significantly increased the antioxidant level, in such as the catalase activity and the total glutathione content in liver compared to the sham group. These results suggested that the combined radon and antioxidant vitamin treatment could effectively inhibit alcohol-induced hepatopathy in mice without any antagonizing action. 相似文献
62.
Matsuda N 《Behaviormetrika》1986,13(19):41-53
"Multidimensional scaling technique was applied to the Brazilian migration matrix in order to identify the functional regions of the nation, using the 1970 census data for males. The results obtained from three types of proximity matrices confirmed the key roles of Minas Gerais and Mato Grosso as the core states in addition to Rio de Janeiro and Sao Paulo. Substantial circulation of migrants among the core states runs counter to the popular notion about the Northeastern states as the major source of labor in Rio de Janeiro and Sao Paulo. The Northeast [was] found to consist of three groups of states: Maranhao, Piaui and Ceara showed a stable clustering, but peripherally located, in all configurations; and, the other two groups failed to form persistent regions across configurations. Though limited in scope, the observed attraction of Espirito Santo and Goias violated the widely held negative effect of distance and deserves further investigation." 相似文献
63.
Single‐layered retardation films with negative wavelength dispersion birefringence made from liquid‐crystalline monomers 下载免费PDF全文
Mika Yamamoto Koichi Endo Yasuhiro Kuwana Isa Nishiyama 《Journal of the Society for Information Display》2017,25(7):405-410
Organic light‐emitting diode displays have a cathode composed of a layer of highly reflective metal. Reflection of external light from this layer can be suppressed with a broadband quarter‐wave plate. Although various types of quarter‐wave plate retardation films have been prepared by copolymerizing, mixing, or laminating multiple polymers, ideal wavelength dispersion has not been achieved with thin retardation films because of their relatively low birefringence and the complexity of the procedure required manufacturing them. In this study, we developed (i) new liquid‐crystalline monomers with negative wavelength dispersion birefringence that we used to obtain thin, single‐layered retardation films suitable for coating and (ii) retardation films with different molecular alignments. We found that the monomers showed high solubility and high regularity of molecular alignment, with less damage to the substrate and alignment films. We also investigated the wavelength dispersion and thermal stability of the films. We succeeded in developing retardation films that had a homeotropic alignment or a hybrid alignment with negative wavelength dispersion. These alignments can be used to obtain antireflection films with an improved viewing angle for organic light‐emitting diode displays or next‐generation thin displays. 相似文献
64.
Atsushi Fukuoka Yuzuru Sakamoto Takanori Higuchi Noriyuki Shimomura Masaru Ichikawa 《Journal of Porous Materials》2006,13(3-4):231-235
Platinum nanowires and nanoparticles were selectively synthesized in mesoporous silicas FSM-16 and HMM-1. The nanowires are 3 nm in diameter and several hundred nm to μm in length with high crystallinity. Pt nanowires and nanoparticles can be isolated by dissolving silica matrix with HF. The Pt wires extracted from organosilica HMM-1 have a nanonecklace structure, while the wires from siliceous FSM-16 have a nanorod structure. The extracted Pt nanoparticles (3 nm in size) on HOPG show the Coulomb staircase phenomena in STM/STS analysis. The mechanism for formation of the Pt nanowires is based on the migration of Pt ions in the mesoporous channels. 相似文献
65.
The Effectiveness of Fish Oil Supplementation in Asthmatic Rats is Limited by an Inefficient Action on ASM Function 总被引:1,自引:1,他引:0
D. T. S. Z. Miranda A. L. Zanatta B. C. L. Dias R. T. H. Fogaça J. B. B. Maurer L. Donatti P. C. Calder A. Nishiyama 《Lipids》2013,48(9):889-897
Episodes of acute exacerbation are the major clinical feature of asthma and therefore represent an important focus for developing novel therapies for this disease. There are many reports that the n-3 fatty acids found in fish oil exert anti-inflammatory effects, but there are few studies of the action of fish oil on airway smooth muscle (ASM) function. In the present investigation, we evaluated the effect of fish oil supplementation on smooth muscle force of contraction in ovalbumin-induced asthmatic Wistar rats, and its consequences on static lung compliance, mucus production, leukocyte chemotaxis and production of proinflammatory cytokines. Fish oil supplementation suppressed the infiltration of inflammatory cells into the lung in asthmatic animals (2.04 ± 0.19 × 106 cells vs. 3.33 ± 0.43 × 106 cells in the control asthmatic group; P < 0.05). Static lung compliance increased with fish oil supplementation in asthmatic rats (0.640 ± 0.053 mL/cm H2O vs. 0.399 ± 0.043 mL/cm H2O; P < 0.05). However, fish oil did not prevent asthma-associated lung eosinophilia and did not affect the concentrations of tumor necrosis factor-α and interleukin-1β in lung tissue or the proportion of the airways obliterated with mucus. Fish oil had no effect on the force of contraction in asthmatic rats in response to acetylcholine (3.026 ± 0.274 mN vs. 2.813 ± 0.364 mN in the control asthmatic group). In conclusion, although fish oil exerts some benefits in this model of asthma, its effectiveness appears to be limited by an inefficient action on airway smooth muscle function. 相似文献
66.
67.
Two-crack propagation paths in a ceramic/metal functionally graded material plate (FGP) under one-cycle temperature change of heating and cooling are considered. When the FGP is subjected to thermal shock, a single crack or multiple cracks often initiate on the ceramic surface during the cooling process and propagate in the FGP. Crack paths are influenced by the heating temperature conditions, a compositional profile of the FGP, the fracture toughness, interaction among multiple cracks, and so on. Transient thermal stresses are treated as a linear quasi-static thermoelastic problem for a plane-strain state. The crack paths are treated under fracture mechanics using the finite-element method. The effects of heating temperature conditions, a compositional profile of the FGP, the fracture toughness, and a crack space on the crack propagation pattern are discussed and are shown in figures. 相似文献
68.
Presently, it has become an urgent and important concern worldwide to reduce the volume of waste and rationally use the waste for electric power generation. Sludge is a dominant part in the family of wastes. Drying of sludge, not only for volume reduction but also for further utilization, is becoming an essential and integral process. On the other hand, as the requirement of new materials production, for example, fine particles of micron or sub-micron scale for advanced materials, some new drying technologies and techniques have emerged. The market-pull may be the direct and active impetus to drying research and development (R&D). In this paper, drying technologies for sludges, fine particles, coatings as well as advanced dewatering are discussed to reflect the “hot” points of drying and dewatering R&D in Japan. And some novel dryers are also presented. 相似文献
69.
Hosomi Ryota Otsuka Ren Arai Hirofumi Kanda Seiji Nishiyama Toshimasa Yoshida Munehiro Fukunaga Kenji 《Food science and biotechnology》2016,25(1):107-112
In an effort to clarify whether the lipid-lowering effect of hemoglobin is due to globin protein or heme, this study investigated the effects of dietary porcine hemoglobin (PH) and porcine globin (PG) on lipids contents of serum, liver, and feces in rats. Five-week-old male Wistar rats were divided into 3 dietary groups of 7 rats each, with one group receiving a control diet and the other groups receiving diets containing 1.25% (w/w) PH or 1.18% (w/w) PG for 4 weeks. The PH diet decreased triacylglycerol content in serum and cholesterol in serum and liver, whereas the PG diet reduced triacylglycerol content in serum and cholesterol in liver. Fecal lipid excretion in the PH group was significantly higher than in the PG group. Therefore, PH affected lipid excretion to feces due to globin protein as well as heme. 相似文献
70.