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11.
Makoto Sasaki Motoki Inoue Yasuyuki Katada Yuuki Nishida Akiyoshi Taniguchi Sachiko Hiromoto Tetsushi Taguchi 《Science and Technology of Advanced Materials》2012,13(6)
Calcium phosphate was formed on nickel-free high-nitrogen stainless steel (HNS) by chemical solution deposition. The calcium phosphate deposition was enhanced by glutamic acid covalently immobilized on the surface of HNS with trisuccinimidyl citrate as a linker. X-ray diffraction patterns and Fourier transform infrared spectra showed that the material deposited on glutamic acid-immobilized HNS within 24 h was low-crystallinity calcium-deficient carbonate-containing hydroxyapatite (HAp). The biological activity of the resulting HAp-coated HNS was investigated by using a human osteoblast-like MG-63 cell culture. The HAp-coated HNS stimulated the alkaline-phosphate activity of the MG-63 culture after 7 days. Therefore, HAp-coated HNS is suitable for orthopedic devices and soft tissue adhesion materials. 相似文献
12.
A scientometric analysis of social science literature is tried by using the machine-readable files of theIBSS 1981–1985. This is a comprehensive international bibliography in social sciences including cultural anthropology, economics,
political science and sociology. Data used were 40,313 monograph records in theIBSS files. First, the number of scholarly monographs was examined by country. As a result, it is shown that a large number of
monographs was published by only a very small number of countries. Second, the number of monographs was examined by language.
A similar pattern as that of countries was observed. Third, the relationship between the publishing country and the language
used is discussed. It is clarified that some languages, such as English, French and Spanish, are used in many countries because
of their historical background such as colonization. Finally, we examined the correlation among the number of published monographs,
GDP, population and the number of people attaining a university education. A regression model that incorporates GDP as explanatory
variables explains well the variation of the number of monographs by countries (R2=0.77). 相似文献
13.
The effects of electrolyte pH and temperature on the structure and properties of anodic oxide films formed on niobium in phosphoric acid solution with the addition of NH4OH for pH adjustment have been investigated. The film thickness formed at the same voltage slightly increased with increasing pH and significantly increased with increasing electrolyte temperature. The capacitance of the film was independent of electrolyte pH in an acid region, while it notably increased with increasing pH in an alkaline region. The relative permittivity of the film changed 43.7-80.5 when the electrolyte pH was increased from 1.6 to 10. The incorporation depth and content of phosphorus in the film were markedly suppressed at pH 10, and nitrogen was found to penetrate into a depth of 70%. Furthermore, the apparent transport number of Nb5+ ion decreased from 0.26 to 0.02 by a pH increase from 1.6 to 10. The notable changes in structure and dielectric properties of the anodic niobia film formed in the alkaline region would primarily be caused by the different incorporation behavior of electrolyte species such as phosphorous and nitrogen. 相似文献
14.
Ikuo Yanase Sachiko Tamai Hidehiko Kobayashi 《Journal of the American Ceramic Society》2003,86(8):1360-1364
Cubic cesium leucite-based compounds, namely cesium leucites, cesium sodium leucites, and cesium lithium leucites, were synthesized using a multistep solid-state reaction method. The thermal expansion properties, in the temperature range of 298-1273 K, for the synthesized cubic cesium leucite-based compounds were examined using high-temperature powder X-ray diffractometry data. The thermal expansions of the cubic cesium leucite-based compounds were found to vary with the chemical composition. For instance, the thermal expansions of Cs0.7 Na0.2 Al0.9 Si2.1 O6 and Cs0.7 Li0.2 Al0.9 Si2.1 O6 were 0.14% at 1273 K and 0.081% at 1073 K, values lower than those of Cs0.9 Al0.9 Si2.1 O6 , which were 0.16% at 1073 K and 0.2% at 1273 K. The results showed that the thermal expansions of the cubic cesium leucite-based compounds changed with ionic substitution at the Cs+ sites because of ionic size differences between Cs+ and the Na+ or Li+ substitutional ions. 相似文献
15.
When rat pleural mononuclear leukocytes were stimulated with 1 μM phorbol myristate acetate (PMA), platelet-activating factor
(PAF)-like activity was detected in the supernatant and the cellular fractions of the incubation mixture, as measured by rabbit
platelet aggregation. C16PAF activity peaked at 30 min in both fractions. Acetyltransferase activity in the microsomal fraction of the stimulated cells
also increased rapidly and showed a peak at 10 min. A protein kinase C inhibitor, staurosporine, and an inhibitor of phospholipase
A2,p-bromophenacylbromide, inhibited stimulated PAF formation in both fractions. Staurosporine also inhibited PMA induced acetyltransferase
activity. The data suggest that PMA stimulates PAF synthesis by the remodeling pathway in rat pleural cells through activation
of both phospholipase A2 and acetyltransferase, and that the acetyltransferase, in turn, may be activated through activation of protein kinase C.
Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl
Ether Lipids, Tokyo, Japan, May 1989. 相似文献
16.
Ryoma UegakiYoko Akiyama Sachiko TojoYoshihide Honda Shigehiro Nishijima 《Journal of power sources》2011,196(23):9856-9861
The degradation mechanism induced by radicals was investigated for Nafion®-117 by solution analysis. Nafion® was exposed independently to three kinds of radicals, OH, H and O2− which were produced separately by γ-irradiation. Based on the eluted elements, the scission site in the membrane was analyzed. The results showed that the scission site was classified into two and these locations were closely relating to oxidative and reductive reactions. The decreasing rate of proton conductivity was more significant under the influence of reductive radicals. The progression of the unzipping reaction of main chain was suggested to be initiated by the production of tertiary carbon radical by reductive radicals such as H and O2− with the aid of OH. The structural degradation such as collapse of cluster and the cluster decomposition as well as the performance degradation was found to be initiated by such reductive radicals. 相似文献
17.
Effects of epoxidized 1,2- or 1,4-polybutadienes on the zinc stearate/calcium stearate synergetic soap-induced thermal stabilization of poly(vinyl chloride) (PVC) were investigated by colorimetry. The remarkable stabilization effects of epoxidized polybutadienes could not be observed on the PVC films without synergetic soaps, while the stabilization of PVC was markedly enhanced by combined use of epoxidized polybutadienes with synergetic soaps. Excessive coloration of cool color-producing zinc chloride-polyene complexes that were the source of abrupt discoloration of stabilized PVC was retarded by using epoxidized polybutadienes together with synergetic soap. The synergism of epoxidized polybutadienes was enhanced with increasing epoxy contents. Moreover, the effect is also clearly dependent on degree of dispersion of epoxidized polybutadienes in PVC. Further colorimetries, infrared (IR), and X-ray photoelectron spectroscopies on the various PVC-containing epoxidized polybutadienes and zinc chloride indicated that the epoxy groups capture the zinc chloride. The synergistic effect between epoxidized polybutadienes and metal soap was ascribed to epoxidized polybutadienes serving as acceptors for the excessive cool color-producing zinc chloride produced by zinc stearate to retard the abrupt discoloration of stabilized PVC. The plate-out phenomenon appeared during the molding process of PVC-containing epoxy compounds was considerably retarded by epoxidized polybutadienes which modified polyols. The polyol-modifying epoxidized polybutadienes also exhibited a marked effect on PVC stabilization with metal soap. 相似文献
18.
Makoto Miyazawa Yasuhiko Irie Kazuki Kashimoto Naoko Nishina Mitsuru Kondo Sachiko Yasue Kenji Maeda Fumio Uchida 《Inorganic chemistry communications》2009,12(4):336-339
Three new complexes, [Zn(dbsf)2(dmf)2] · 5.5dmf (dbsf = 4,4′-sulfonyldibenzoate) (1β), [Cu(tdsa)(phen)2] · 1.5EtOH (tdsa = 5,5′-thiodisalicylate, phen = 1,10-phenanthroline) (2), and [Cu(sdp)(phen) · Cu(Hsdp)(phen)(CH3COO)] · 3EtOH (sdp = 4,4′-sulfonyldiphenolate) (3) were prepared and structurally characterized. Complex 1β shows a one-dimensional coordination framework constructed from bridges between Zn(II) centers with two ligands. Complex 2 is a monomeric complex, which assembles by π–π interactions. Complex 3 shows a unique two-dimensional coordination framework that is constructed from two Cu(II) centers, sdp, and Hsdp. The redox properties of these three complexes were characterized by solid-state cyclic voltammetry. Complexes 1β and 3 show irreversible reduction waves because of the reduction of their sulfone sites. Complex 2 shows an irreversible oxidation wave because of oxidation of the sulfide site. 相似文献
19.
Helena A. Soini Donald Wiesler Sachiko Koyama Christophe Féron Claude Baudoin Milos V. Novotny 《Journal of chemical ecology》2009,35(5):580-589
Whereas the house mouse (Mus domesticus) has been studied extensively in terms of physiology/behavior and pheromonal attributes, the evolutionarily related mound-building
mouse (Mus spicilegus) has received attention only recently due to its divergent behavioral traits related to olfaction. To date, no chemical studies
on urinary volatile compounds have been performed on M. spicilegus. The rationale for our investigations was to determine if there are differences in urinary volatiles of intact and castrated
M. spicilegus males and to explore further whether this species could utilize the same or structurally similar pheromones as the male house
mouse, M. domesticus. The use of capillary gas chromatography/mass spectrometry (GC-MS) together with sorptive stir bar extraction sampling enabled
quantitative comparisons between the intact and castrated M. spicilegus urinary profiles. Additionally, through GC-MS and atomic emission (sulfur-selective) detection, we identified qualitative
molecular differences between intact M. spicilegus and M. domesticus. A series of volatile and odoriferous lactones and the presence of coumarin were the unique features of M. spicilegus, as was the notable absence of 2-sec-butyl-4,5-dihydrothiazole (a prominent M. domesticus male pheromone) and other sulfur-containing compounds. Castration of M. spicilegus males eliminated several substances, including δ-hexalactone and γ-octalactone, and substantially decreased additional compounds,
suggesting their possible role in chemical communication. Some other M. domesticus pheromone components were also found in M. spicilegus urine. These comparative chemical analyses support the notion of metabolic similarities as well as the uniqueness of some
volatiles for M. spicilegus, which may have a distinct physiological function in reproduction and behavior. 相似文献
20.
Akira Kaieda Dr. Masashi Takahashi Hiromi Fukuda Dr. Rei Okamoto Dr. Shinji Morimoto Masayuki Gotoh Takahiro Miyazaki Yuri Hori Satoko Unno Dr. Tomohiro Kawamoto Dr. Toshimasa Tanaka Dr. Sachiko Itono Terufumi Takagi Dr. Hiroshi Sugimoto Dr. Kengo Okada Dr. Weston Lane Dr. Bi-Ching Sang Dr. Kumar Saikatendu Dr. Shinichiro Matsunaga Dr. Seiji Miwatashi 《ChemMedChem》2019,14(24):2093-2101
We identified novel potent inhibitors of p38 mitogen-activated protein (MAP) kinase using a structure-based design strategy, beginning with lead compound, 3-(butan-2-yl)-6-(2,4-difluoroanilino)-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one ( 1 ). To enhance the inhibitory activity of 1 against production of tumor necrosis factor-α (TNF-α) in human whole blood (hWB) cell assays, we designed and synthesized hybrid compounds in which the imidazo[4,5-b]pyridin-2-one core was successfully linked with the p-methylbenzamide fragment. Among the compounds evaluated, 3-(3-tert-butyl-2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridin-6-yl)-4-methyl-N-(1-methyl-1H-pyrazol-3-yl)benzamide ( 25 ) exhibited potent p38 inhibition, superior suppression of TNF-α production in hWB cells, and also significant in vivo efficacy in a rat model of collagen-induced arthritis (CIA). In this paper, we report the discovery of potent, selective, and orally bioavailable imidazo[4,5-b]pyridin-2-one-based p38 MAP kinase inhibitors. 相似文献