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41.
Eiko Yasui 《Tetrahedron letters》2009,50(33):4762-4765
We have developed a novel method for the synthesis of 3,4-diarylpyrrole-2,5-dicarboxylates via α-diazo esters, which are easily obtained from phenylalanine derivatives. Utilizing this method, intermediates of bioactive compounds having the structure of 3,4-diarylpyrrole-2,5-dicarboxylates were synthesized. 相似文献
42.
Conductive polymer three-dimensional microstructures were photofabricated utilizing the two-photon absorption of a sensitizer
dye. The resulting three-dimensional structures were excised from the transparent polymer sheet using a micro-manipulator.
The processing precisions for the vertical direction of the conductive polymer three-dimensional microstructure obtained in
the transparent polymer sheet were evaluated in the present study. As a result, for the configurations of the obtained polypyrrole
line deposition, the line height/line width ratios were around 5: 1; this ratio is higher than that of other UV resin works
(h: w 2:4–3: 1) and the cross section distortion is not negligible for maintaining the higher reproducibility of the photofabrication. 相似文献
43.
F. Hindle G. Mouret S. Eliet M. Guinet A. Cuisset R. Bocquet T. Yasui D. Rovera 《Applied physics. B, Lasers and optics》2011,104(4):763-768
The generation of cw-THz radiation by photomixing is particularly suited to the high resolution spectroscopy of gases; nevertheless,
until recently, it has suffered from a lack of frequency metrology. Frequency combs are a powerful tool that can transfer
microwave frequency standards to optical frequencies and a single comb has permitted accurate (10−8) THz frequency synthesis with a limited tuning range. A THz synthesizer composed of three extended cavity laser diodes phase
locked to a frequency comb has been constructed and its utility for high resolution gas phase spectroscopy demonstrated. The
third laser diode allows a larger tuning range of up to 300 MHz to be achieved without the need for large frequency excursions,
while the frequency comb provides a versatile link to be established from any traceable microwave frequency standard. The
use of a single frequency comb as a reference for all of the cw-lasers eliminates the dependency of synthesized frequency
on the carrier envelope offset frequency. This greatly simplifies the frequency comb stabilization requirements and leads
to a reduced instrument complexity. 相似文献
44.
Nishizuka T Fujita Y Sato Y Nakano A Kakino A Ohshima S Kanda T Yoshimoto R Sawamura T 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2011,87(3):104-113
Lectin-like oxidized LDL receptor-1 (LOX-1) is an endothelial receptor for oxidized LDL (oxLDL) and plays multiple roles in the development of cardiovascular diseases. We screened more than 400 foodstuff extracts for identifying materials that inhibit oxLDL binding to LOX-1. Results showed that 52 extracts inhibited LOX-1 by more than 70% in cell-free assays. Subsequent cell-based assays revealed that a variety of foodstuffs known to be rich in procyanidins such as grape seed extracts and apple polyphenols, potently inhibited oxLDL uptake in Chinese hamster ovary (CHO) cells expressing LOX-1. Indeed, purified procyanidins significantly inhibited oxLDL binding to LOX-1 while other ingredients of apple polyphenols did not. Moreover, chronic administration of oligomeric procyanidins suppressed lipid accumulation in vascular wall in hypertensive rats fed with high fat diet. These results suggest that procyanidins are LOX-1 inhibitors and LOX-1 inhibition might be a possible underlying mechanism of the well-known vascular protective effects of red wine, the French Paradox. 相似文献
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Noriko Hata Shiho Hieda Mika Yamada Rie Yasui Hideki Kuramitz Shigeru Taguchi 《Analytical sciences》2008,24(7):925-928
The formation of a liquid organic ion associate in an aqueous sample was applied to the concentration and determination of cadmium in environmental water samples. Cadmium was converted into a complex with 2-(5-bromo-2-pyridylazo)-5-(N-propyl-N-sulfopropylamino)phenol (5-Br-PAPS) in a 40-mL sample solution, and was extracted into a liquid ion associate of phenolsulfonate and benzethonium during phase formation. More than 400-fold enrichment was easily attained by this technique, because the volume of the liquid organic phase formed was very small, ca. 2 microL. After dilution of the organic phase with a small volume of 2-methoxyethanol, the cadmium in the solution was determined by GF-AAS. The detection limit was 0.09 ng/L (3sigma(b)). This method was applied to the determination of cadmium in river water and seawater. 相似文献
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