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41.
42.
Kenta Miura Takeshi Tanemura Shunya Yamamoto Masaki Sugimoto 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2007,263(2):532-534
We fabricated fused-silica substrates which emit blue light by using Si-ion implantation and high-temperature annealing. Photoluminescence peak wavelengths are around 400 nm, and the peak intensities can be remarkable after annealing above 1150 °C. 相似文献
43.
Temperature dependences of the soft phonon frequency and the damping constant in Tris-Sarcosine Calcium Chloride (TSCC) single crystal have been investigated between 5K and 100K by using a Fourier-transform far-infrared spectrometer. It has been observed that the soft phonon frequency decreases gradually and the damping constant increases as the transition temperature is approached from below The damping constant varies from 7cm-1 a 90K to less than 0.5cm-1 at 5K. It has been found that the damping constant is approximately proportional to temperature below about 60K. 相似文献
44.
K Horino H Nishiura T Ohsako Y Shibuya T Hiraoka N Kitamura T Yamamoto 《Canadian Metallurgical Quarterly》1998,78(5):603-617
HL-60 cells derived from a human promyelocytic leukemia underwent apoptosis by heat treatment. When the heat-treated HL-60 cells were injected into guinea pig skin, monocyte/macrophage infiltration was observed 24 or 36 hours later, and the apoptotic cells were phagocytically cleared by 48 hours after their injection. The infiltration and clearance patterns were quite different from those observed in injection of necrotic or boil-fixed HL-60 cells. The apoptotic cells released a monocyte chemotactic factor in vitro 24 hours after the heat treatment. The chemotactic factor generated was identified as the cross-linked homodimer of S19 ribosomal protein by its immunologic and physicochemical properties. A serine protease that inactivates the monocyte chemotactic factor was also released from the apoptotic cells 30 hours after the heat treatment. A super infusion of this protease into the skin where the apoptotic cells had been injected diminished the number of infiltrated monocytes. The present results indicate an important role of the S19 ribosomal protein dimer in the phagocytic clearance of apoptotic cells. 相似文献
45.
The hypocotyl of Arabidopsis is well suited for the analysis of cell elongation because it elongates without cell division. We have isolated a new class of recessive mutants, petit1 (pet1), which are defective in aspects of hypocotyl elongation. The short-hypocotyl phenotype of pet1 is caused by shortened cells. The cells of the elongation zone of the hypocotyl are often deformed. pet1 also shows defects in elongation of the roots, flower stalk, leaves, petals, pedicels, and siliques, and these defects cannot be repaired by the application of auxin, gibberellin, brassinolide, or an inhibitor of ethylene biosynthesis. The short-hypocotyl phenotype of pet1 is pronounced only in growth medium supplemented with sucrose, which has promotive effects on hypocotyl elongation. In pet1 this effect is much reduced, causing the sucrose-dependent short-hypocotyl phenotype of pet1. pet1 accumulates more soluble sugars than the wild type and also shows more intensive iodo-starch staining in the cotyledon and hypocotyl. These results indicate that PETIT1 is involved in a sugar-dependent elongation process that may include correct assembly of expanding cell wall architecture. 相似文献
46.
Rapid determination of the membrane potential of mitochondria in small biopsy specimens of the liver
Y Yamamoto M Obara W Isselhard J Sturz T Morimoto T Minor S Saad K Ozawa 《Canadian Metallurgical Quarterly》1995,27(3):145-150
In liver transplantation, graft viability is ideally to be determined before implantation. Integrity of mitochondria may be a prerequisite to a viable graft. A new method is presented, which allows for the determination of the membrane potential of mitochondria (MPM; mV) in state 4 respiration within 50 min in 40-mg specimens, employing rhodamine 123 as a probe. Normal control showed a MPM of 239.2 mV. Storage in saline at 37 degrees C yielded an impaired MPM of 153.5 mV within 3 h. The cold storage at 1 degree C could preserve MPM at quasi-normal after 3 h but reduced it significantly after 24 h to 222.2 mV in saline (p < 0.005 vs. control) and 231.0 mV in UW solution (p < 0.05 vs. control): the difference between the 24-hour values was significant (p < 0.05). 相似文献
47.
K Iguchi M Hamatake R Ishida Y Usami T Adachi H Yamamoto K Koshida T Uchibayashi K Hirano 《Canadian Metallurgical Quarterly》1998,253(3):766-770
Endothelin-1 (ET-1) is a cardiovascular peptide that binds to two distinct receptors, ET(A) and ET(B), resulting in systemic and regional vasoconstriction, alteration in sodium excretion, mitogenesis, and release of other vasoactive peptides such as atrial natriuretic peptide (ANP). A role for ET-1 has been proposed in congestive heart failure (CHF) based on the increase in circulating ET-1 in this cardiovascular disease state. The present study determined the cardiorenal and endocrine responses to chronic selective oral ETA antagonism in experimental CHF. Two groups of conscious dogs underwent 21 days of pacing-induced CHF. These groups included a control untreated group (n = 6) and a group that received an orally active ET(A) receptor antagonist (A-127722, Abbott Pharmaceuticals, 5 mg/kg PO bid, n = 6). Each group was studied at baseline before the onset of CHF and after 14 and 21 days of CHF. Compared with the CHF control group, the ET(A) receptor antagonism group at 14 days of CHF showed lower mean arterial pressure and systemic vascular resistance. Similarly, ET(A) receptor antagonism markedly attenuated the increase in circulating ANP despite similar atrial pressures. At 21 days of CHF, ET(A) receptor antagonism lowered pulmonary artery pressure, pulmonary vascular resistance, and systemic vascular resistance in association with a higher cardiac output. Plasma ANP remained suppressed. Despite the lower mean arterial pressure and circulating ANP in the ET(A) receptor antagonist group, the absolute decrease in sodium excretion from baseline was less compared with the untreated CHF control group. The present investigation supports the conclusion that endogenous ET-1 participates in the systemic and pulmonary vasoconstriction, the elevation of ANP, and the sodium retention that characterize this model of experimental CHF, suggesting a potential therapeutic role for ET(A) receptor antagonism in CHF. 相似文献
48.
Uchiyama K. Arakawa F. Narita S. Aoki H. Kawasaki I. Matsui S. Yamamoto M. Nakagawa N. Kudo I. 《Micro, IEEE》1993,13(5):12-22
The Gmicro/500, which features a RISC-like dual-pipeline structure for high-speed execution of basic instructions and represents a significant advance for the TRON architecture, is presented. Upwardly-object-compatible with earlier members of the Gmicro series, this microprocessor uses resident dedicated branch buffers to greatly enhance branch instruction execution speed. Its microprograms simultaneously use dual execution blocks to execute high-level language instructions effectively. Fabricated with a 0.6-μm CMOS technology on a 10.9-mm×16-mm die, the chip operates at 50/66 MHz and achieves a processing rate of 100/132 MIPS 相似文献
49.
K Yoshida M Yoshimoto K Sasaki T Ohnishi T Ushiki J Hitomi S Yamamoto M Sigeno 《Canadian Metallurgical Quarterly》1998,74(4):1654-1657
A new stable substrate applicable to the observation of DNA molecules by atomic force microscopy (AFM) was fabricated from a ultrasmooth sapphire (alpha-Al2O3 single crystal) plate. The atomically ultrasmooth sapphire as obtained by high-temperature annealing has hydrophobic surfaces and could not be used for the AFM observation of DNA. However, sapphire treated with Na3PO4 aqueous solution exhibited a hydrophilic character while maintaining a smooth surface structure. The surface of the wet-treated sapphire was found by x-ray photoelectron spectroscopy and AFM to be approximately 0.3 nm. The hydrophilic surface character of the ultrasmooth sapphire plate made it easy for DNA molecules to adhere to the plate. Circular molecules of the plasmid DNA could be imaged by AFM on the hydrophilic ultrasmooth sapphire plate. 相似文献
50.
Manabu Sato Tatsuo Yamamoto Toshiyasu Meguro Kazuhiko Yamanouchi 《Sensors and actuators. B, Chemical》1994,20(2-3):205-212
The sensitivity, transient response and sensitivity mechanism of a surface acoustic wave humidity sensor using porous anodically oxidized aluminium (alumina) films as mechanical interfaces have been studied theoretically and experimentally. It is found that the sensitivity of alumina films of 1.0 μm thickness is -0.034 m/(s %RH) and is the same order as that of polyimide films. The transient response of alumina films to humidity is about one order faster than that of polyimide films. For the sensitivity mechanism, the phase-velocity change is attributed to the mechanical perturbation caused by the absorption of water molecules. The equivalent density change of alumina films between 0 and 100%RH is about 0.7%. In addition, the actual stiffness constants of alumina films are two orders less than those of bulk alumina. 相似文献