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1.
Takashi Yoshitake Ryuji Iizuka Kaoru Fujino Osamu Inoue Kenji Yamagata Hitoshi Nohta Masatoshi Yamaguchi 《Analytical sciences》2004,20(12):1687-1690
An improved high-performance liquid-chromatographic (HPLC) assay for the simultaneous determination of serotonin (5-HT) and 5-hydroxyindole-3-acetic acid (5-HIAA) in human urine is reported. Following the automated precolumn derivatization of urinary 5-HT and 5-HIAA with benzylamine, the derivatives are separated by isocratic elution on a reversed-phase C18 semi-microbore column, and are fluorometrically detected at an excitation wavelength of 345 nm and an emission wavelength of 480 nm. The detection limits of 5-HT and 5-HIAA are 7 and 5 nmol/l in urine (0.7 and 0.5 fmol/20-microl injection). The proposed automatic method permits a highly selective and sensitive determination of 5-HT and 5-HIAA in human urine without any sample purification. 相似文献
2.
Yukinobu Mild Atsushi Onae Tomizo Kurosawa Eiichi Sakuma 《International Journal of Infrared and Millimeter Waves》1993,14(11):2345-2359
A system for measuring the absolute frequency of a far-infrared (FIR) laser is described. Josephson point contacts have been utilized in the system as a frequency harmonic mixer connecting microwaves and optically pumped CH3OH laser lines. The Josephson point contacts are capable of generating beat signals of 90 GHz microwaves and FIR waves of up to 4.25 THz. To measure the frequency of the beat signals from the Josephson junction with a frequency counter, tracking oscillators have been developed, which tracks the beat signals by phase locking and regenerate clean signals for frequency counting. It is shown that the absolute frequency can be measured to an accuracy of about 100 Hz by using the tracking oscillators. 相似文献
3.
We have recently reported on dodecamer peptides (HPPMDFHKAMTR, CHPQPLKSRNPL) which recognize 52-58th and 197-203rd amino acid sequences of glucose oxidase (GOx) by screening via a phage random peptide library. In this study, a side-chain protected peptide monomer (PPM) was synthesized using two peptides (HPPMDFHKAMTR, SHPQPLKSRNPL) and acryloyl chloride. The peptide-conjugated polymer (PCP) was copolymerized with PPMs and N,N-diethylacrylamide (DEAA). The affinity of PCPs to GOx was estimated using surface plasmon resonance detection. This study suggests that PCP is a valuable molecular recognition biomolecule. 相似文献
4.
5.
We developed DNA-conjugated polymer for DNA chip fabrication. A 30 mer probe DNA and disulfide bridges were covalently attached to the polymer side chain. The DNA-conjugated polymer can be specifically adsorbed on a gold substrate surface by a self-assembly technique. The interaction between fully matched DNA and DNA-conjugated polymer was investigated by surface plasmon resonance (SPR) technique. The DNA-conjugated polymer-modified gold surface highly recognized fully matched DNA, rather than unmatched DNA. Therefore, DNA-conjugated polymer can be used for novel DNA chip fabrication. 相似文献
6.
Toshiyuki Oyama Akira Kitamura Eiichi Sato Masao Tomoi 《Journal of polymer science. Part A, Polymer chemistry》2006,44(8):2694-2706
The factors affecting pattern‐forming properties in reaction development patterning were examined with polyarylates with various bisphenol moieties. The developability of the photosensitive polyarylates was dependent on the properties of the subtituent (R) in the bisphenol moieties. The development time decreased in the following order: R?C(CH3)2 > fluorenyl unit ? phenolphthalein unit > C(CF3)2 > SO2. This order agreed with that of the reactivity between the polyarylates and ethanolamine, and these orders can be explained by pKa of the bisphenol used to prepare the polyarylates. The development with NH2? R′? OH resulted in successful positive‐tone pattern formation. However, pattern formation with the developers containing NH2? R′? OCH3 was unsuccessful. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2694–2706, 2006 相似文献
7.
Summary It is shown that certain singular integral operators with variable kernels leave invariant theL
v,
-spaces studied by Campanato, Stampacchia, Peetre and others. Our results extend Peetre's work on convolution operators. 相似文献
8.
Thirty three compounds were obtained from the bulbs of Urginea maritima (Liliaceae). The compounds were identified by means of fast atom bombardment mass spectrometry (FAB-MS), nuclear magnetic resonance (1H-NMR), (13C-NMR), nuclear overhauser effects (NOE) and two dimensional (2D) NMR. Ten of them were new natural compounds. Nine were bufadienolides and only one was lignan in these compounds. 相似文献
9.
10.
Suzuki Masayasu Watamabe Nobuyuki Tamiya Eiichi Kataoka Tetsuro Tokunaga Tohru Karube Isao 《Applied biochemistry and biotechnology》1987,15(3):191-200
A novel tumor-detection system consisting of complementmediated cytolytic reaction and an image processing system was developed
for the simple and rapid determination of tumor cells.
The present system consists of a CCD image sensor, image memory board, personal computer, and microscope.
When monoclonal antibody 3C4, which is specific to the guinea pig hepatoma L-10, was added to cell suspension, only L-10 cytolysis
occurred. Cytolysis caused a decrease in brightness of the cells observed by phase-contrast microscopy. The phase contrast
image of the cells before cytolysis was converted to a digitalized signal and stored in computer memory. After cytolysis,
a brightness threshold above that of lysed cells was subtracted from the digitalized signal and compared to the signal stored
before reaction.
L-10 cells in mixed cell suspension were determined specifically by the system. Measurement time was only 2 sec and overall
time, including reaction time, was approximately 30 min. Since this method does not require a cell washing process, automation
of the whole system is possible. 相似文献