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71.
H Nishizono Y Hanamure T Matsuzaki K Ito M Ohyama 《Canadian Metallurgical Quarterly》1997,100(12):1436-1441
Detoxification of cyclophosphamide is effected, in part, by hepatic class 1 aldehyde dehydrogenase (ALDH-1)-catalyzed oxidation of aldophosphamide, a pivotal aldehyde intermediate, to the nontoxic metabolite, carboxyphosphamide. This enzyme is found in erythrocytes as well. Detoxification of aldophosphamide may also be effected by enzymes, viz. certain aldo-keto reductases, that catalyze the reduction of aldophosphamide to alcophosphamide. Such enzymes are also found in erythrocytes. Not known at the onset of this investigation was whether the contribution of erythrocyte ALDH-1 and/or aldo-keto reductases to the overall systemic detoxification of circulating aldophosphamide is significant. Thus, NAD-linked oxidation and NADPH-linked reduction of aldophosphamide catalyzed by relevant erythrocyte enzymes were quantified. ALDH-1-catalyzed oxidation of aldophosphamide (160 microM) to carboxyphosphamide occurred at a mean (+/- SD) rate of 5.0 +/- 1.4 atmol/min/rbc (red blood cell). Aldo-keto reductase-catalyzed reduction of aldophosphamide (160 microM) to alcophosphamide occurred at a much slower rate, viz. 0.3 +/- 0.2 atmol/min/rbc. Thus, at a pharmacologically relevant concentration of aldophosphamide, viz. 1 microM, estimated aggregate erythrocyte ALDH-1-catalyzed aldophosphamide oxidation, viz. 2.0 micromol/min, was only about 3% of estimated aggregate hepatic enzyme-catalyzed aldophosphamide oxidation, viz. 72 micromol/min; however, this rate is greater than the estimated flow-limited rate of aldophosphamide delivery to the liver by the blood, viz. 1.5 micromol/min. These observations/considerations suggest an important in vivo role for erythrocyte ALDH-1 in systemic aldophosphamide detoxification. Erythrocyte ALDH-1-effected oxidation of other aldehydes to their corresponding acids, e.g. retinaldehyde to retinoic acid, may also be of pharmacological and/or physiological significance since a wide variety of aldehydes are known to be substrates for ALDH-1. 相似文献
72.
Phase equilibria in Fe-Cu-X (X: Co, Cr, Si, V) ternary systems 总被引:2,自引:0,他引:2
Cui Ping Wang Xing Jun Liu Ikuo Ohnuma Ryosuke Kainuma Kiyohito Ishida 《Journal of Phase Equilibria and Diffusion》2002,23(3):236-245
Phase equilibria on the Fe-Cu side in the Fe-Cu-X (X: Co, Cr, Si, V) system were experimentally determined over the temperature
range of 1073–1273 K. Based on the present results and previous works, the thermodynamic assessments of the phase equilibria
in the Fe-Cu-X system were evaluated using the Calculation of Phase Diagram (CALPHAD) method. The Gibbs energies (G) of the bcc, fcc, and liquid phases are described by the subregular solution model, and a set of thermodynamic parameters
enable us to calculate various isothermal and vertical sections and the miscibility gaps of the solid and liquid phases. 相似文献
73.
Highly Stretchable,Global, and Distributed Local Strain Sensing Line Using GaInSn Electrodes for Wearable Electronics
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For identifying human or finger movement, it is necessary to sense subtle movements at multiple points, including the local strain and global deformation simultaneously; however, this has not yet been realized. Therefore, a highly stretchable, global, and distributed local strain sensing electrode made of GaInSn and polydimethylsiloxane is developed for wearable devices. To investigate the electrical properties of multiple sections of the GaInSn electrode when stretching, tensile, cyclic, and three‐point‐bending tests are performed. The results demonstrate that the electrode can withstand a strain up to 50% and has little hysteresis without any delay. Moreover, the distributed local strain and global strain can be simultaneously measured using just a single electrode line. Finally, a prototype of a data glove as an application of the strain sensing line is manufactured, and it is demonstrated that the folding state of fingers could be identified. The proposed technology may allow the creation of a lightweight master hand manipulator or 3D data entry device. 相似文献
74.
K Matsuzaki H Tahara J Inokoshi H Tanaka R Masuma S Omura 《Canadian Metallurgical Quarterly》1998,51(11):1004-1011
Novel brominated and halogen-less azaphilone (oxoisochromane) derivatives, 5-bromoochrephilone and dechloroisochromophilone IV, and known derivatives, dechloroisochromophilone III and isorotiorin, were isolated from the culture broth of a producing organism of isochromophilones I and II (azaphilones inhibiting gp120-CD4 binding), Penicillium multicolor FO-2338, fermented in a medium containing potassium bromide. Nineteen azaphilone-related compounds isolated from the above strain and from other fungi were tested for the inhibition of gp120-CD4 binding and the structure-activity relationship is discussed. Consequently, 5-bromoochrephilone is the strongest inhibitor (IC50, 2.5 microM). A halogen atom at C-5, a proton at C-8 and a diene structure in C-3 side chain of 6-oxoisochromane ring are necessary for gp120-CD4 binding. 相似文献
75.
Y Sakakibara T Jikuya S Adachi K Watanabe K Matsuzaki T Mitsui S Suzuki S Kawano H Unno T Doi 《Canadian Metallurgical Quarterly》1998,51(13):1080-1083
A 71-year-old man was admitted to our hospital with massive GI bleeding and followed by acute myocardial infarction. Severe three vessel coronary artery disease with poor left ventricular performance (EF: 40%) was demonstrated by coronary angiography. He was referred for CABG. He had also cholecystitis, which needed surgical treatment simultaneously. Combined CABG and cholecystectomy were performed without using gastroepiploic artery as a bypass graft, and through separate median sternotomy and through right upper transrectal laparotomy. Postoperative course was uneventful. This combined procedure is beneficial for the patients with acute cholecystitis and unstable angina. 相似文献
76.
77.
H Yamamoto K Watanabe W Takayama S Yamada Y Fujita I Honda S Watanabe O Matsuzaki M Ryu 《Canadian Metallurgical Quarterly》1995,25(6):282-285
Fibrolamellar carcinoma of the liver (FLC), which is very rare in Japan, is reported to be frequently accompanied by lymph node metastasis in Europe and the United States. We describe a 22-year-old man with recurrent FLC in the lymph nodes after undergoing partial hepatectomy. He underwent a second operation for removal of recurrent lymph node tumors in the mediastinum and abdominal cavity one year after initial surgery. However, a third operation became necessary seven months later, because of recurrence in a lymph node in the abdominal cavity. We discuss the management of lymph node metastasis from FLC. 相似文献
78.
79.
Ryosuke O. Suzuki Takamichi Ogawa Katsutoshi Ono 《Journal of the American Ceramic Society》1999,82(8):2033-2038
The possible use of ozone to produce higher oxides was analyzed thermodynamically. Because the activity of oxygen in ozone is ∼1018 at room temperature and ∼108 at 773 K, ozone may react with metals to yield higher-oxidation-state products than does an ambient pressure of pure oxygen. In agreement with this thermodynamic prediction, silver oxides (AgO and Ag2 O) were synthesized experimentally by blowing a gas mixture of 6 vol% ozone and oxygen through a water-cooled lance. Neither Ag3 O4 nor Ag2 O3 was detected. Slow oxygen diffusion into a metal and/or reaction products and decomposition of unstable oxides that are formed successively are obstacles to practical applications of syntheses via ozone oxidation. 相似文献
80.
Shiga N. Nakajima S. Otobe K. Sekiguchi T. Kuwata N. Matsuzaki K.-i. Hayashi H. 《Microwave Theory and Techniques》1991,39(12):1987-1994
The design and test of an X -band monolithic four-stage low-noise amplifier (LNA) with 0.5 μm-gate pulse-doped GaAs MESFETs for application in a direct broadcast satellite (DBS) converter is presented. The key feature of the research is a detailed demonstration of the advantages of using series feedback with experiments and simulations. This LNA shows an excellent input VSWR match under 1.4 as well as a noise figure of 1.67 dB and a gain of 24 dB at 12 GHz. The noise figure, the gain and VSWRs exhibit very little bias current dependence due to the exceptional features of the pulse-doped structure FETs and the optimized circuit design. Insensitivity to bias current implies performance stability in the face of process fluctuations. Thus, the yield of chips with noise figures of less than 2.0 dB is as high as 62.5%, and the variations of gain and VSWR are highly uniform as well 相似文献