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排序方式: 共有328条查询结果,搜索用时 218 毫秒
1.
2.
Hironobu Ishiyama Ryo C. Yanagita Kazune Takemoto Natsumi Kitaguchi Yuuki Uezato Yasunori Sugiyama Masashi Sato Yasuhiro Kawanami 《Journal of Applied Glycoscience》2020,67(3):95
D-Allose (D-All), a C-3 epimer of D-glucose (D-Glc), is a naturally rare monosaccharide, which shows anti-proliferative activity against several human cancer cell lines. Unlike conventional anticancer drugs, D-All targets glucose metabolism and is non-toxic to normal cells. Therefore, it has attracted attention as a unique “seed” compound for anticancer agents. However, the anti-proliferative activities of the other rare aldohexoses have not been examined yet. In this study, we evaluated the anti-proliferative activity of rare aldohexoses against human leukemia MOLT-4F and human prostate cancer DU-145 cell lines. We found that D-All and D-idose (D-Ido) at 5 mM inhibited cell proliferation of MOLT-4F cells by 46 % and 60 %, respectively. On the other hand, the rare aldohexoses at 5 mM did not show specific anti-proliferative activity against DU-145 cells. To explore the structure–activity relationship of D-Ido, we evaluated the anti-proliferative activity of D-sorbose (D-Sor), 6-deoxy-D-Ido, and L-xylose (L-Xyl) against MOLT-4F cells and found that D-Sor, 6-deoxy-D-Ido, and L-Xyl showed no inhibitory activity at 5 mM, suggesting that the aldose structure and the C-6 hydroxy group of D-Ido are important for its activity. Cellular glucose uptake assay and western blotting analysis of thioredoxin-interacting protein (TXNIP) expression suggested that the anti-proliferative activity of D-Ido is induced by inhibition of glucose uptake via TXNIP-independent pathway. 相似文献
3.
Toru Nagaoka Yoshiaki Morisada Masao Fukusumi Tadashi Takemoto 《Journal of Materials Processing Technology》2011,211(9):1534-1539
The conditions for sound butt-joints of 5056 aluminum alloy containing 4.6 mass% Mg using Zn-xAl (x = 5, 13, and 38 mass%) solder at the relevant temperatures were investigated. Each solder foil was inserted between faying surfaces of 5056 aluminum rods. Ultrasonic vibration at a frequency of 19 kHz was applied to the faying surfaces through an aluminum substrate at soldering temperatures for 4 s in air. The strength of obtained solder joints was measured by tensile tests. The microstructure in the solder layer after the soldering process was evaluated with an SEM-EDX. The results of tensile tests revealed that joints soldered under the liquidus temperature of Zn-Al solders showed higher strength than joints soldered over the liquidus temperature. In the joints soldered over the solder liquidus temperature, the joint strength decreased with an increase in soldering temperature. It was caused by the formation of MgZn2 in the solder layer due to dissolution of 5056-Al into the solder liquid during the soldering process. On the other hand, ultrasonic-assisted soldering under the solder liquidus temperature suppressed dissolution of 5056-Al and improved the joint strength by reducing the formation of MgZn2. 相似文献
4.
Masahiro Nagae Tetsuo Yoshio Yoshito Takemoto Jun Takada 《Journal of the American Ceramic Society》2001,84(5):1175-1177
For pure molybdenum nitrided at 1373 K in NH3 gas, microstructural observations of a molybdenum nitride layer were conducted through a transmission electron microscope. The molybdenum nitride layer consisted of two molybdenum nitrides: an outer one of γ-Mo2 N and an inner one of β-Mo2 N. A great number of (011)[0 1] type twins were observed in the β-Mo2 N phase, whereas the microstructure of the γ-Mo2 N phase was almost free from lattice defects except for slightly observed {111}〈112〉 type twin. 相似文献
5.
Toru Nagaoka Yoshiaki Morisada Masao Fukusumi Tadashi Takemoto 《Metallurgical and Materials Transactions B》2010,41(4):864-871
To obtain sound butt-joints of 5056 aluminum alloy rods, ultrasonic-assisted soldering was conducted using Zn-18Sn and Zn-60Sn
alloys. Each solder foil was inserted between rods of 5056 aluminum alloy. Ultrasonic vibration was propagated to faying surfaces
at soldering temperatures below the liquidus temperature of the solder alloys, and then the samples were air cooled to room
temperature. The optimum vibration time at the soldering temperature must be more than 2 seconds to have complete wetting
and less than 4 seconds to avoid excessive dissolution of the 5056 alloy. The 5056 alloy joints soldered using quasi-melting.
Zn-Sn alloys showed greater strength than the joints soldered at the temperatures over its respective liquidus temperature.
As the soldering temperature was increased, the increased formation of the intermetallic compound Mg2Sn or phases containing Mg generated by dissolution of 5056 into the solder layer decreased the joint strength. Ultrasonic-assisted
soldering at an optimum temperature between solidus and liquidus of the Zn-Sn alloys is an important consideration for producing
sound joints with sufficient strength. 相似文献
6.
Mototsugu Takemoto Takuma Karasawa Hiroshi Mizumachi Mikio Kajiyama 《The Journal of Adhesion》2013,89(1):85-96
A series of ethylene vinyl acetate copolymer (EVA) were blended with various kinds of tackifiers and the miscibility between the components was investigated. The miscibility of the blend is illustrated as a phase diagram. The EVA and modified rosin systems tended to have a phase diagram with lower critical solution temperature (LCST), whereas the EVA and petroleum resin systems tended to have that with upper critical solution temperature (UCST). The phase diagrams of EVA/tackifier resins systematically changed as VAc content in the copolymer increased, which is accounted for by the classical Flory-Huggins theory. 相似文献
7.
Li-Ngee Ho Hiroshi Nishikawa Tadashi Takemoto 《Journal of Materials Science: Materials in Electronics》2011,22(5):538-544
The effects of different copper fillers with different morphology and particle size have been studied in terms of electrical resistivity and thermal stability on the electrically conductive adhesives. The copper fillers used in this study were prepared by wet chemical reduction, electrolytic and gas atomization method, respectively. The as cured ECAs filled with different type of Cu fillers showed significant difference in electrical resistivity. Cu filler with smaller particle size showed higher packing density and larger surface area, which would enhance formation of conductive channels and increased conductive network in the ECAs, leading to a lower electrical resistivity. In addition, thermal stability of the ECAs were investigated under high temperature exposure at 125 °C and high humidity aging at 85 °C/85% RH for 1,000 h. Results showed that ECAs with Cu fillers of relatively small particle size and rough particle surface have excellent thermal stability due to enhanced adhesion and contact area between Cu fillers and the polymer matrix. A very low resistivity at an order of magnitude of 10?4 ?? cm could be maintained for these ECAs after 1,000 h at 125 and 85 °C/85% RH. 相似文献
8.
Okikazu Hirabaru Tomohiro Nakase Kenji Hanabusa Hirofusa Shirai Kiichi Takemoto Nobumasa Hojo 《大分子材料与工程》1984,121(1):59-68
Secondary fuel cells based on oxygen reduction of platinum electrode modified by polymers and metal-phthalocyanine (Mt = Fe(III), Co(II), Ni(II), and Cu(II)) were studied. The discharge curves for the platinum electrode modified by poly(2-vinylpyridine) (or polystyrene) and Co-phthalocyanine in 30% KOH aqueous solution, for a 30 min charge at 500 μA, followed by a 100 μA discharge showed a stable plateau at about ?0.24 V SCE (Saturated Calomel Electrode). The open circuit voltage (vs. Zn) of the cell was 1.2 V, and the discharge capacity was of 46 A · h/kg. For this battery there was no significant decay in its characteristics after more than 30 charge-discharge cycles. In Mt-phthalocyanines, the values decreased in the order of Co(II) > Fe(III) > > Cu(II) > Ni(II). From a cyclic voltammogram for the electrode modified by the polymer and Co-Pc, the cathodic reactions were discussed. 相似文献
9.
Rockwell hardness measurement at an elevated temperature has been proposed as an evaluation method for the curing characteristics of thermosetting molding compounds. This method is convenient and has a high accuracy over a wide range of curing, Using a cone indenter, the following advantages are brought about: a good correspondence with acetone extraction test, in showing the degree of cure of the internal part of a molding rather than that of the skin layer, and a higher sensitivity in measuring higher degrees of cure. On examining curing behavior of commercial phenolic molding compounds by this method, an inflection point was observed on a plot of the hardness vs log curing time. This critical point has been called “the minimum cure time”, beyond which the molding exhibits good physical properties. 相似文献
10.
Active 4-dodecanoyl-2-nitrophenyl esters of β-alanine, β-alanyl-β-alanine, and β-alanyl-β-alanyl-β-alanine were prepared, and tried to polymerize in various solvents. Nonpolar solvents were found to be convenient for the polycondensation reaction. The yield of the polycondensation was high for the monopeptide ester, and less for the dipeptide and tripeptide esters. The effect of temperature on the polycondensation reaction was also studied. 相似文献