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81.
K Satsuta M Motoyama A Aoyama T Shintaku H Ikeno K Iino K Sekine H Kataoka 《Canadian Metallurgical Quarterly》1994,61(1):47-53
After ingestion of an unknown dose of detajmium, a 14-year-old female collapsed with asystolia. Resuscitation efforts were not successful. A medicolegal autopsy was carried out, and blood, liver and gastric content were extracted and analyzed by gas chromatography-mass spectrometry (GC-MS). After derivatization with acetic anhydride, detajmium and twelve of its derivatives and metabolites were identified. The main metabolic pathways include hydroxylation and subsequent O-methylation of the indol ring, and oxidation as well as reduction of the C-21 hydroxyl function. Cleavage of the N-alkyl side-chain is a further, possibly non-enzymatic degradation pathway. Artifact formation induced by acetylation included dehydratation of the hydroxyl function of C-21 and the N-alkyl side-chain. The detajmium concentration in blood of the decreased was determined by high-performance liquid chromatography with fluorimetric detection (12 micrograms/ml). 相似文献
82.
K Kataoka I Hisamitsu N Sayama T Okano Y Sakurai 《Canadian Metallurgical Quarterly》1995,117(6):1145-1147
From the standpoints of long-term stability and simple handling, a glucose sensor composed of totally synthetic sensing moieties should be of great advantage. This study was performed to demonstrate the feasibility of a novel glucose sensing system in an aqueous milieu based on a change in the fluorescence on competitive binding between a fluorescent diol compound and glucose toward a phenylborate compound. 6,7-Dihydroxy-4-methyl-coumarin (DHMC) was selected as a fluorophore, and 3-propionamidophenylboronic acid (PAPBA) as a phenylborate compound. The relationship between the glucose concentration and fluorescence intensity was linear in the range of 0 to 500 mg/dl of glucose. The availability of various derivatives of DHMC and phenylborate compounds allows the incorporation of these functionalities on the tip of an optical fiber to construct an opto-sensing system for glucose. 相似文献
83.
M Kataoka LP Sri Rohani M Wada K Kita H Yanase I Urabe S Shimizu 《Canadian Metallurgical Quarterly》1998,62(1):167-169
Seventy mother-newborn pairs were studied for hepatitis C viremia to evaluate the risk of vertical transmission of hepatitis C virus from human immunodeficiency virus-negative mothers. Forty-five mothers were hepatitis C virus-RNA positive: 4 to 45 children were positive at birth and during follow-up. The level of viremia plays an important role in vertical transmission. 相似文献
84.
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86.
Takayuki Tomaru Shinji Miyoki Masatake Ohashi Kazuaki Kuroda Takashi Uchiyama Toshikazu Suzuki Akira Yamamoto Takakazu Shintomi Akitoshi Ueda Daisuke Tatsumi Shuichi Sato Koji Arai Masaki Ando Koji Watanabe Kenji Nakamura Masahiko Watanabe Kazuhiko Ito Izumi Kataoka Hiroaki Yamamoto Brett Bochner Yaron Hefetz 《Applied optics》2003,42(7):1306-1307
87.
Electron accumulation on the metal sides of two Schottky diodes connected metal to metal was observed as a result of the temporary variation of bias between the semiconductor sides of both diodes. The potential of the metals was found to be predictable by a theory based on a property of the Schottky diode. 相似文献
88.
A selective and sensitive method has been developed for the determination of secondary amines by gas chromatography (GC). After removal of primary amines by the reaction with o-phthaldialdehyde, secondary amines were converted into their N-diethylthiophosphoryl derivatives and then measured by GC with flame photometric detection using a DB-1701 capillary column. The derivatives were sufficiently volatile and stable to give single symmetrical peaks. The detection limits of secondary amines were ca. 0.05-0.2 pmol per injection. N-Methylcyclohexylamine was used as an internal standard. The calibration curves for secondary amines in the range 1-20 nmol were linear and sufficiently reproducible for quantitative determination. This method was successfully applied to small urine samples without prior clean-up. Overall recoveries of secondary amines added to urine samples were 91-105%. By using this method, secondary amines in urine samples could be analysed without any influence from primary amines and other coexisting substances. The analytical results of secondary amine content in urine samples of normal subjects are presented. 相似文献
89.
Ichihiko Takahashi Tokuharu Yoshii Hiroo Iidaka Eisuke Fujii Kazuyoshi Matsuoka 《Fatigue & Fracture of Engineering Materials & Structures》1993,16(1):37-51
The fatigue strength of non-load-carrying fillet welded joints of KE36(TMCP) steel was studied. Both residual stress measurements and fatigue tests were carried out, with the plate thickness, the plate width and the heat input being varied. Specimens given a Post Weld Heat Treatment (PWHT) were also prepared. The plate width had no effect on the fatigue strength, because it hardly affected the transverse residual stresses at the weld toe. However, the heat input influenced the transverse residual stress distribution, and a significant difference in fatigue strength due to the heat input was observed, especially when N≥ 106 cycles. It was also found that PWHT removed almost all the residual stresses at the weld toe, improving the fatigue strength drastically. In this study, the values of stress concentration factor K2 were estimated by Machida's method and it was concluded that the thickness effect resulted from a combination of both stress concentration and residual stresses with the contribution of the latter being particularly significant for N≥ 106 cycles. 相似文献
90.