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81.
Min‐Jung Bae Takeshi Ishii Kanako Minoda Yukiko Kawada Tatsuya Ichikawa Taiki Mori Miya Kamihira Tsutomu Nakayama 《Molecular nutrition & food research》2009,53(6):709-715
(–)‐Epigallocatechin gallate (EGCg) is the major component of green tea and is known to show strong biological activity, although it can be easily oxidized under physiological conditions. In this study, we indicate that EGCg is stable in human serum and that human serum albumin (HSA) stabilizes EGCg under aerobic condition. Although EGCg is usually decomposed within 1 h in aqueous solution at neutral pH, EGCg in serum and phosphate buffer (pH 7.4) containing HSA was stable over 1 h, even at neutral and slightly alkaline pH. Under these conditions, EGCg binds to HSA non‐covalently. The sulfhydryl group acts as an antioxidant for EGCg oxidation. Incubation of EGCg with HSA is accompanied by the oxidation of a free sulfhydryl group in HSA. These results suggest that the antioxidant property and the binding capacity of HSA contribute to the stabilization of EGCg in human serum. 相似文献
82.
Leaird D.E. Shen S. Weiner A.M. Sugita A. Kamei S. Ishii M. Okamoto K. 《Photonics Technology Letters, IEEE》2001,13(3):221-223
We present what we believe to be the first demonstration of femtosecond pulse train generation from an arrayed-waveguide grating. Terahertz-rate bursts of femtosecond pulses are produced with the rate determined by the arrayed-waveguide delay spacing 相似文献
83.
AN EXPERIMENTAL AND STATISTICAL INVESTIGATION OF SURFACE FATIGUE CRACK INITIATION AND GROWTH 总被引:1,自引:0,他引:1
Y. Ochi A. Ishii S. K. Sasaki 《Fatigue & Fracture of Engineering Materials & Structures》1985,8(4):327-339
Surface fatigue crack studies were carried out and statistically analysed from rotating bend fatigue tests in the high cycle region for three metals, copper, stainless steel and mild steel with four ferrite grain sizes. Quantitative observations of the initiation and growth behavior, including coalescence of closely spaced cracks, are discussed and a limiting condition for coalescence is proposed. Statistical properties of initiation, propagation and propagation rate of surface cracks are examined and the effect of different metals and grain sizes is discussed. 相似文献
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Kiyoyuki Shimizu Tomohito Sunagawa Keijiro Arimura Hideshi Hattori 《Catalysis Letters》1999,63(3-4):185-188
Cyclohexane isomerization to methylcyclopentane over sulfated zirconia is markedly enhanced in the presence of isopentane
which acts as a hydride transfer agent to facilitate the slow step of hydride transfer from cyclohexane to isopropyl cation.
This was revealed by deuterium tracer studies.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
87.
Yokoyama Kiyoko Ishii Naohiro Naka Ken-Ichi 《IEEE transactions on bio-medical engineering》1986,(3):308-314
A software system was produced to digitize neuronal images and to extract a set of simple parameters from the digitized images. The system was designed to classify a large number of neurons based on simple and automatically extracted features. The system was used to characterize catfish retinal ganglion cells. Several examples of parameter extraction and classification are presented. 相似文献
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