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1.
A flow-injection system for the determination of 3-hydroxybutyrate in serum is described. 3-Hydroxybutyrate dehydrogenase is immobilized on poly(vinyl alcohol) beads and incorporated in a flow-injection system. 1-Methoxy-5-methylphenazinium methylsulphate reacts with enzymatically generated NADH to give H2O2, which is detected chemiluminometrically with the reaction of luminol and hexacynoferrate(III). Serum is diluted and filtered through an ultrafiltration membrane. The system responds linearly to injected samples (80 μl) in the concentration range 0.5–300 μM; the detection limit is 0.1 μM. The within-day relative standard deviation (n = 90) for 58 μM 3-hydroxybutyrate in serum is 0.8%. The maximum throughout is 20 samples per hour. The immobilized enzyme is stable for at least 1 month. 相似文献
2.
A flow-injection system is described for the determination of d-mannitol. Mannitol dehydrogenase is immobilized on poly(vinyl alcohol) beads and packed in a column (5 cm × 4 mm i.d.). The NADH formed is detected fluorimetrically. The response is linear between 5 × 10?7 and 1 × 10?4 M mannitol and the detection limit is 1 × 10?7 M. The throughput is 30 samples per hour. The reactor is stable for at least 8 weeks. 相似文献
3.
Sbin-Ichi Nagai Taisei Ueda Akito Nagatsu Keiko Nakaoka Nobutoshi Murakami Jinsaku Sakakibara Michiko Fujita Yoshihiro Hotta 《Journal of heterocyclic chemistry》1998,35(2):329-332
5,8-Methanoquinazolines fused with imidazoles 4a-4b , thiadiazoles 5–6 , pyrimidines 7, 9, 11 and 12 , and 1,3,5-triazine 13 were prepared starting from (5R,8S)-2-amino-8,9,9-trimethyl-5,6,7,8-tetrahydro-5,8-methanoquinazoline 3 . Most compounds possessed central nervous system stimulant activities. 相似文献
4.
Masaki Tachibana Motohisa Furusawa Nobutoshi Kiba 《Journal of inclusion phenomena and macrocyclic chemistry》1995,22(4):313-329
Extraction of carbazole in heptane was performed at 25±1°C with an aqueous dimethyl sulfoxide (DMSO) medium containing -cyclodextrin (CD) at consecutive concentrations in the range of 0–10 mM. The fluorescence intensity of carbazole remaining in the heptane phase was measured by synchronous scanning fluorimetry. The apparent formation constant (K
f) for a 1:1 carbazole: CD inclusion complex in water-DMSO medium was determined by using a linear plot of the distribution ratio calculated from the fluorescence intensities vs. the -CD concentration. The values thus obtained ranged from 477 M–1 in a 10% v/v DMSO medium to 12.1 M–1 in a 60% v/v medium. Good linear relationships were observed between logK
f and the DMSO concentration ([DMSO]), and also between logK
f and the logarithm of the distribution coefficient (K
d) for carbazole. The formation constant in 100% water was estimated to be approximately 1.0×103 M–1 on the basis of the logK
f vs. [DMSO] and the logK
f vs. logK
d correlations. 相似文献
5.
Choji Kashima Yumiko Konno Nobutoshi Yoshiwara Tadakuni Tajima 《Journal of heterocyclic chemistry》1982,19(6):1535-1536
The regioselective synthesis of 3-hydroxyisoxazoles and 5-isoxazolones is accomplished by the reaction of β-amino α,β-unsaturated esters with hydroxylamine hydrochloride in the presence of appropriate bases. The total yield of isoxazole derivatives is sensitively influenced on the β-substituent group of the esters. 相似文献
6.
Shin-Ichi Nagai Taisei Ueda Masatoshi Takamura Akito Nagatsu Nobutoshi Murakami Jinsaku Sakakibara 《Journal of heterocyclic chemistry》1998,35(2):293-296
Novel camphor-1,2,4-triazines fused with imidazole 2–3 , thiadiazole 4 , 1,2,4-triazole 7 , pyrimidine 9–13 and 1,3,5-triazine 14 , were synthesized starting from (5R,8S)-3-amino-5,9,9-trimethyl-5,6,7,8-tetrahydro-5,8-methano-1,2,4-benzotriazine 1 . Evaluation of central nervous system stimulant activity demonstrated that the presence of a N-N group at C-3 position of 1,2,4-benzotriazine will be essential for the activity. 相似文献
7.
Satoru Tamura Masafumi Kaneko Susumu Tanimura Nobutoshi Murakami 《Tetrahedron letters》2010,51(13):1678-3843
A new polyketide peumusolide A was disclosed as an unprecedented NES non-antagonistic inhibitor for nuclear export of MEK, a promising scaffold for antitumor agents with novel mechanism of action, from Peumus boldus Molina. The absolute stereostructure as well as optical purity was established by use of the two synthesized enantiomeric model lactones. In addition, the Δε values in their CD spectra were demonstrated to be the conclusive index for determination of not only configuration at C-3 but also optical purity of natural congeneric polyketides. Peumusolide A was revealed to show NES non-antagonistic action by the biotinylated probe and to inhibit proliferation of MEK-activated tumor cells selectively. 相似文献
8.
Nobutoshi Kiba Youhei Inoue Masaki Tachibana Kazue Tani Hitoshi Koizumi 《Analytical sciences》2003,19(8):1203-1206
A chemiluminometric flow-through sensor for the simultaneous determination of glucose (Glu) and 3-hydroxybutyrate (HB) in a single sample has been developed. Coimmobilized 3-hydroxybutyrate dehydrogenase/NADH oxidase/peroxidase, a support material, and coimmobilized glucose dehydrogenase/NADH oxidase/peroxidase were packed sequentially in a transparent PTFE tube. The tube was then placed in front of a photomultiplier tube as a flow cell. A two-peak recording was obtained by one injection of the sample solution. The peak heights of the first and second peaks were dependent on the concentrations of HB and Glu, respectively. The calibration graphs for HB and Glu were linear at 0.05-10 and 0.1-30 microM, respectively. The maximum sample throughput was 30 h(-1). The sensor was stable for two weeks. 相似文献
9.
Norimichi Tsumura Daisuke Kawazoe Toshiya Nakaguchi Nobutoshi Ojima Yoichi Miyake 《Optical Review》2008,15(6):292-294
A simple regression-based model of skin diffuse reflectance is developed based on reflectance samples calculated by Monte
Carlo simulation of light transport in a two-layered skin model. This reflectance model includes the values of spectral reflectance
in the visible spectra for Japanese women. The modified Lambert Beer law holds in the proposed model with a modified mean
free path length in non-linear density space. The averaged RMS and maximum errors of the proposed model were 1.1 and 3.1%,
respectively, in the above range. 相似文献
10.
Aminohydroxy anion (), dissociated species of hydroxylamine, was demonstrated to be nucleophilic on oxygen atom from INDO calculation, and to give directly O-alkylhydroxylamines. 相似文献