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81.
H Tomita K Egashira M Kubo-Inoue M Usui M Koyanagi H Shimokawa M Takeya T Yoshimura A Takeshita 《Canadian Metallurgical Quarterly》1998,18(9):1456-1464
We recently showed that chronic inhibition of NO synthesis by N(omega)-nitro-L-arginine methyl ester (L-NAME) causes coronary vascular remodeling (ie, vascular fibrosis and medial thickening) in rats. To test the hypothesis that the inhibition of NO synthesis induces inflammatory changes in the heart, we characterized the inflammatory lesions that occurred during L-NAME administration and determined whether inflammation involved the induction of monocyte chemoattractant protein-1 (MCP-1) in vivo. During the first week of L-NAME administration to Wistar-Kyoto rats, we observed a marked infiltration of mononuclear leukocytes (ED1-positive macrophages) and fibroblast-like cells (alpha-smooth muscle actin-positive myofibroblasts) into the coronary vessels and myocardial interstitial areas. These inflammatory changes were associated with the expression of proliferating cell nuclear antigen and MCP-1 (both mRNA and protein). The areas affected by inflammatory changes, as well as the expression of MCP-1 mRNA, declined after longer (28 days) treatment with L-NAME and were replaced by vascular and myocardial remodeling. Our results support the hypothesis that the inhibition of NO synthesis induces inflammatory changes in coronary vascular and myocardial tissues and involves MCP-1 expression. Results also suggest that the early stages of inflammatory changes are important in the development of later-stage structural changes observed in rat hearts. 相似文献
82.
K Seki J Sakurada M Murai A Usui HK Seong H Jitsukawa S Masuda 《Canadian Metallurgical Quarterly》1995,39(8):615-617
A supportive method for clonal identification of Staphylococcus aureus strains was devised. Culture supernatant obtained by cellophane surface culture was subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) without performing any concentration procedure prior to electrophoresis. The combined use of cellophane surface culture and SDS-PAGE was convenient for determining whether the strains belonged to the same clone or not when conducted in conjunction with other tests for bacteriological characterization. 相似文献
83.
When two-layered artificial teeth are used, acrylic resin occlusal parts can be removed from base parts and used directly as resin patterns for casting, which facilitates fabrication of metal occlusal surfaces. Because these teeth were made of acrylic resin, it was easy to modify occlusal morphology before converting to metal. Application of two-layered artificial teeth to achieve lingual contact occlusion brought about sufficient masticatory forces and denture stability and resulted in patient satisfaction. 相似文献
84.
A series of the Chevrel phases, Mo6−xRuxTe8 and Mo6Te8−xSx (x=0, 1, 2), has been prepared and the various physical properties, such as the elastic modulus, Debye temperature, and electrical resistivity, have been evaluated. The relationships between several properties of the compounds have also been studied. Young’s modulus and Debye temperature of Mo6−xRuxTe8 and Mo6Te8−xSx increase with increasing x value. The relationship between the Vickers hardness and Young’s modulus shows ceramic characteristics for Mo6−xRuxTe8, while they show glass-like characteristics for Mo6Te8−xSx. The electrical resistivities of Mo6−xRuxTe8 and Mo6Te8−xSx increase with increasing x value. 相似文献
85.
In this study, we perform experiments and analyses to examine the warpage of Al/AlN layered structures connected by direct brazing. Al/AlN layered structures are considered under the high temperature fluctuations that occur in the brazing and baking processes. Three Al thicknesses are considered, using A3003 (JIS code) Al to clarify the variations in warpage. For the inelastic analysis, two types of constitutive model are used for Al: a non-linear kinematic hardening model considering cyclic hardening, viscoplasticity, and creep, and a conventional isotropic hardening model. Then, it is shown that the warpage in both brazing and baking processes can be simulated well using the kinematic hardening model. 相似文献
86.
Takashi Matsumura Eiji Usui 《International Journal of Machine Tools and Manufacture》2010,50(5):467-473
The cutting force and the chip flow direction in peripheral milling are predicted by a predictive force model based on the minimum cutting energy. The chip flow model in milling is made by piling up the orthogonal cuttings in the planes containing the cutting velocities and the chip flow velocities. The cutting edges are divided into discrete segments and the shear plane cutting models are made on the segments in the chip flow model. In the peripheral milling, the shear plane in the cutting model cannot be completely made when the cutting point is near the workpiece surface. When the shear plane is restricted by the workpiece surface, the cutting energy is estimated taking into account the restricted length of the shear plane. The chip flow angle is determined so as to minimize the cutting energy. Then, the cutting force is predicted in the determined chip flow model corresponding to the workpiece shape. The cutting processes in the traverse and the contour millings are simulated as practical operations and the predicted cutting forces verified in comparison with the measured ones. Because the presented model determines the chip flow angle based on the cutting energy, the change in the chip flow angle can be predicted with the cutting model. 相似文献
87.
Naoki Harikai Shin Saito Atsuko Tanaka & Kenji Kinoshita 《International Journal of Food Science & Technology》2009,44(9):1778-1785
We developed a method using an internal standard to determine the amount of unprocessed genetically modified organisms (GMO) in foods as GMO weight per weight of total food (w/wtf ) using real-time PCR. Food samples were spiked with an internal standard, a ColE1 plasmid, and DNA was extracted from the samples using a silica membrane-type kit and analysed using real-time PCR. The relationship between the GMO amount and the copy number ratio of the transgene to ColE1 in 0.1–5% w/wtf GM soybean powders was found to have a correlation coefficient ( r ) of 0.97. GMO was quantified in food samples spiked with GM soybean (final amount 0.5% w/wtf GMO). The average GMO amount ranged from 0.35% to 0.63% w/wtf . The results show that our method should be useful for quantifying unprocessed GMO in foods. We also developed a duplex assay, which is simpler and more accurate than the simplex assay. 相似文献
88.
The shape changes in GaAs nanocrystals deposited on Si substrate have been studied as a function of the coverage by transmission electron microscopic observations in order to see the growth mechanism from the viewpoint of the surface energy and the lattice strain energy between the nanocrystal and the substrate. When GaAs was deposited on the Si(100) surface, the shape of the GaAs nanocrystals changes from stepped mound, hut cluster to dome structure with increasing the coverage. The shape changes are responsible for decreasing the total free energy caused by the lattice strain energy with the substrate and surface energy depending on the crystal size. 相似文献
89.
Kazuhiro Hashima Kazuhiro Usui Luxiang Fu Takashi Inoue Ken‐ichiro Fujimoto Kentaro Segawa Tomiya Abe Hitoshi Kimura 《Polymer Engineering and Science》2008,48(6):1207-1213
A super‐ductile PBT alloy with excellent heat resistance was successfully fabricated by reactive blending of poly(butylene terephthalate) (PBT) with poly(ethylene‐co‐glycidyl methacrylate) together with linear low density polyethylene (LLDPE) and hydrogenated styrene‐butadiene‐styrene block copolymer (SEBS). It possesses a unique tensile stress–strain curve with no yielding point and large elongation at break, moreover, the alloy did not show serious deterioration of the mechanical properties by high temperature annealing at 150°C for 96 h. The structure‐properties relationship is discussed on the basis of transmission electron microscopy, differential scanning calorimetry, dynamic mechanical analysis, and wide‐angle X‐ray diffraction analysis. The outstanding ductile nature seems to come from the negative pressure effect of LLDPE (or LLDPE/SEBS) particles that dilates the PBT ligament matrix to enhance the local segment motions. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers. 相似文献
90.
Takenori Nitta Takayuki Usui Hiroaki Iino Akira Ohno Jun‐ichi Hanna 《Electrical Engineering in Japan》2021,214(1):10-17
We have designed and synthesized a new liquid crystalline phenylbenzothienobenzothiphene derivative, Ph‐BTBT‐4S‐3, in order to investigate the carrier transport properties in highly ordered smectic liquid crystal phase at a wide temperature range lower than room temperature enough to analyze them. Ph‐BTBT‐4S‐3 exhibits smectic E (SmE) phase, which is the one of highly ordered smectic liquid crystal phases, at the wide temperature range from 200°C to under ?130°C. Thanks to its wide temperature range of SmE phase, we could reveal the carrier transport properties in the low temperature range, which were well explained on the basis of Gaussian disorder model having a Gaussian width, σ, of 87 meV, which was larger than those of typical nonpolar liquid crystals of 40?60 meV and was attributed to additional dipole of a thioether group in the side chain. 相似文献