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1.
Hideki Taguchi Yuzuru Takahashi Hiroki Miyamoto 《Journal of the American Ceramic Society》1985,68(10):264-C
Specimens of partially stabilized zirconia were slip cast from aqueous suspensions and sintered at 1500°C for 3 h. The relative density of the cast specimens and the firing shrinkage of the sintered specimens depend on the milling time for the suspension. Vickers hardness and KIC values of 11.46±s0.07 GN/m2 and 6.10 ±0.04 MN.m3/2 , respectively, were obtained for all sintered specimens. The dispersion of the suspension is important in increasing the relative density of the cast specimens. 相似文献
2.
S Matsuoka K Mori O Nakano Y Yuasa Y Taguchi Y Hayabuchi Y Kuroda 《Canadian Metallurgical Quarterly》1997,156(9):704-708
Twenty-two children with chronic hepatitis serologically positive for hepatitis C virus (HCV) were treated with interferon-alpha (IFN-alpha). Liver biopsy showed chronic active hepatitis in 13 and chronic persistent hepatitis in 9 patients. A sustained clearance of HCV was observed in 8/22 children 12 months after the administration of IFN-alpha for 26 weeks, associated with normalization of HCV core antibody. Of these eight patients six had HCV genotype III and two HCV genotype II or IV. Hepatitis relapsed in seven other patients after completion of IFN-alpha with an increase in HCV core antibody titre, five with HCV genotype II, and two with HCV genotype III or IV. A second course of IFN-alpha suppressed the reactivation of HCV in all seven patients. Three of seven responders who relapsed after the first course remained negative for HCV RNA 12 months after their second course of IFN-alpha. However, the remaining four patients with HCV genotype II again relapsed after completing their second course of IFN-alpha. Seven children with the HCV genotype II resistant to IFN, including 8 weeks of IFN-beta administration, and showed no significant reduction in HCV core antibody titre. CONCLUSION: The genotype of HCV (III) and a reduction in the core antibody titre appear to be useful parameters for predicting the response to IFN-alpha therapy. 相似文献
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5.
T Hanaoka A Sawaumi K Ohtsuka K Nakata K Taguchi O Shimojima 《Canadian Metallurgical Quarterly》1996,9(3):257-264
The nature of the events whereby the reactive intermediates resulting from the bioactivation of bromobenzene and furosemide induce hepatotoxicity is unknown. To examine a role for disturbances in intracellular calcium homeostasis, secondary to a depletion in cellular reduced glutathione (GSH) and reduced protein thiols (PSHs), isolated mouse hepatocytes were exposed to cytotoxic concentrations of bromobenzene or furosemide. Cytosolic calcium concentration, as well as thiol status, was determined. The incubation of hepatocytes with 3.0 mM bromobenzene, and subsequent additions (1.2 mM) of the agent every hour, resulted in significant GSH depletion. The loss of plasma membrane integrity at 1.5 h preceded both a rise in the cytosolic Ca2+ concentration and depletion of total PSH content. Furosemide (1.0 mM) produced a 70% depletion in cellular GSH content in isolated hepatocytes. The initiation of cell damage occurred concurrently with both a rise in the cytosolic Ca2+ concentration and a depletion of total PSH content 4 h following furosemide addition. Since the increase in cytosolic Ca2+ did not precede cytotoxicity, these results do not support an initiating role for Ca2+ deregulation in bromobenzene and furosemide hepatotoxicities. In addition, depletion of PSH content did not correlate with bromobenzene- or furosemide-induced cytotoxicity. 相似文献
6.
Kyoko Kawagishi Hiroshi Harada Akihiro Sato Atsushi Sato Toshiharu Kobayashi 《JOM Journal of the Minerals, Metals and Materials Society》2006,58(1):43-46
The fourth-generation nickel-based single-crystal superalloys, which contain large amounts of refractory metals for strengthening
and platinum group metals for topologically close-packed phase prevention, show excellent high-temperature strength. However,
these alloying elements seem to decrease high-temperature oxidation resistance. In this study, nickel-based superalloys with
various amounts of tantalum, rhenium, and ruthenium were examined in isothermal and cyclic exposures at 1,100°C to investigate
the effect on the oxide growth rate and resistance to scale spallation. Ruthenium and rhenium were found to degrade the oxidation
resistance by the vaporization of their oxide. Tantalum-rich oxide in the spinel layer acts to stabilize ruthenium and rhenium
oxide in the scale. The addition of hafnium and yttrium is effective in improving the oxidation resistance of ruthenium-containing
nickel-based superalloys. 相似文献
7.
The electrochemical reduction of nitrate ion was studied by cyclic voltammetry on Pt(1 1 1) and [n(1 1 1) × (1 1 1)] stepped Pt surfaces, where n (=14, 10, 7, 6, 5, 4, 3, 2) is the number of terrace atoms, in 0.1 M HClO4 + 10 mM KNO3. The electrocatalytic nitrate reduction was found to hardly proceed on Pt(1 1 1) in the hydrogen adsorption region, while the electrocatalytic activity was improved with the increase in the step density. Inactivation was observed in the presence of adsorbed hydrogen or nitrate-derived reduced adsorbate, i.e. adsorbed NO, on (1 1 1) step sites. It was, therefore, concluded that the electrocatalytically active NO3− species does not adsorb on the (1 1 1) terraces but on the (1 1 1) monoatomic steps. The nitrate reduction current increased with the step density in a non-linear relationship. The overall current density at 0.21 V (RHE) corresponding to the peak potential of the main electrocatalytic nitrate reduction wave which was maximum at n = 2, abruptly increased with short terraces, i.e. n < 5, where the current wave of adsorbed hydrogen on the Pt stepped surface with comparatively narrow (1 1 1) terraces, denoted as Hnt, also appeared unmodified for n < 5 on voltammograms recorded in 0.1 M HClO4 in the absence of nitrate. 相似文献
8.
Michiko Kusunoki Kyoko Yonemitsu Yukichi Sasaki Yukio Kubo 《Journal of the American Ceramic Society》1993,76(3):763-765
Zirconia (ZrO2 ) particles (average diameter, 30 nm) were observed in an in situ heating experiment up to 1200°C using a 400-kV high-resolution electron microscope. Thermal vibration of atoms on a (001) surface plane was observed at 1100°C. At 1200°C, grain growth and sintering phenomena were recorded on a videotape, showing (100) lattice planes migrating on a surface of a particle. Direct observation of the sintering process on a lattice level was accomplished for the first time. 相似文献
9.
The compositions of ester- and amide-linked fatty acids from ceramides of human vernix caseosa were described with emphasis
on the distribution of the branched-chain fatty acid (BCFA). Two novel ceramides were isolated from vernix caseosa in the
course of this study: the acylated type of esterified α-OH-hydroxyacid/sphingosine ceramide (Cer[EAS]) and nonacylated type
of non-OH fatty acid/hydroxysphingosine ceramide (Cer[NH]). Their chemical structures were identified by nuclear magnetic
resonance and chemical procedure. The Cer[EAS] was an acylceramide and consisted of the highest concentrations of ester- and
amide-linked BCFA (62 and 67%, respectively). The iso- or anteiso-branching structures of the aliphatic chains were confirmed
by the mass spectra of their picolinyl or pyrrolidide derivatives. As a whole, amide-linked fatty acids of ceramides 1–7 and
Cer[NH] were normal types of straight-chain fatty acids with or without α- or ω-hydroxylation. The BCFA concentrations of
amide-linked fatty acids in these ceramides (ceramides 1–7 and Cer[NH]) were low and less than 10%. The BCFA thus occurred
exclusively in a novel acylceramide of Cer[EAS] in the vernix caseosa. 相似文献
10.
Composite particles composed of solid powders and polymer were prepared by semichemical recycle of wasted plastics. Waste expanded polystyrene was used as raw materials of polymer matrix of composite particles. Both magnetite and silicon carbide powders were used as solid powders to give thermal and electric conductivity and magnetization, respectively. In the experiment, the oil‐phase dissolving expanded polystyrene was dispersed in fine droplets into the continuous water phase. Two kinds of powders were added at the same time or separately in the O/W dispersion. Composite particles were found to have the structure that polymer particle was covered with two kinds of solid powders. The mean diameter of composite particles and the content of each solid powder were strongly affected by the addition time when silicon carbide powder was added into the dispersion. Furthermore, it was found that the gradient adhesion layer due to two solid powders was able to be formed on the surface of polymer particle. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 483–488, 2003 相似文献