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  • 1
    Electronic Resource
    Electronic Resource
    Vitamin B6 phototoxicity induced by UVA radiation (2000)
    Springer
    Archives of dermatological research 292 (2000), S. 562-567 
    Details
    ISSN: 1432-069X
    Keywords: Keywords Vitamin B6 ; UVA ; Phototoxicity ; ESR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We have previously reported that pyridoxine shows UVA-induced cytotoxicity. Four other vitamin B6 compounds (pyridoxal, pyridoxamine, pyridoxal phosphate, and pyridoxamine phosphate) are metabolically more important in vivo than pyridoxine. These compounds were examined for UVA phototoxicity to cultured human fibroblasts. The cytotoxicity was measured by post-UVA irradiation colony-forming ability. All the B6 compounds except pyridoxal phosphate showed cytotoxicity. Pyridoxamine phosphate, which is the most important form of vitamin B6 in vivo, had the strongest cytotoxic effect. To examine the involvement of reactive oxygen species in the phototoxicity, we performed an electron spin resonance study using the spin trapping agent, 5,5-dimethyl-1-pyrroline N-oxide, and diethylenetriaminepentaacetic acid. We failed to detect radicals derived from vitamin B6. The cytotoxic effect remained in UVA-irradiated solutions for at least 30 min after the end of UVA irradiation. Hydrogen peroxide was produced in the solution, but the amount was not enough to cause cytotoxicity. In addition, the cells from xeroderma pigmentosum patients who belong to group A or C showed survival curves similar to those of normal fibroblasts. This suggests that cyclobutane pyrimidine dimers or 6-4 photoproducts of DNA were not involved in this damage. These findings suggest that UVA-induced vitamin B6 cytotoxicity is caused by toxic photoproducts resulting from irradiated vitamin B6.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004030000174
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  • 2
    Electronic Resource
    Electronic Resource
    Adrenal nonhyperfunctioning adenoma and nonadenoma: CT attenuation value as discriminative index (1995)
    Springer
    Abdominal imaging 20 (1995), S. 559-562 
    Details
    ISSN: 1432-0509
    Keywords: Adrenal neoplasms ; Abdomen, CT ; Adrenal adenoma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Background When an asymptomatic adrenal mass is incidentally discovered on abdominal CT scans, the distinction between a nonhyperfunctioning adenoma and a nonadenoma would be important. Methods We evaluated the CT findings of 36 adrenal masses (14 nonhyperfunctioning adenomas, 22 nonadenomas) in 34 patients with no evidence of hormonal hypersecretion. CT attenuation values of adrenal masses on CT scans were calculated by setting a circular region of interest as large as possible in the center of each adrenal mass. Results Below 20 HU in CT attenuation values, all adrenal masses, except one case of ganglioneuroma with myxomatous change, were nonhyperfunctioning adenomas. With an arbitrary threshold of 20 HU, the sensitivity of CT attenuation values in distinguishing nonhyperfunctioning adenomas from nonadenomas was 64%, the specificity was 95%, and the accuracy was 83%. When decreasing the threshold to 15 HU, the sensitivity was 64%, the specificity was 100%, and the accuracy was 86%. The CT attenuation value on noncontrast CT was more useful for making this distinction than the size and interior homogeneity. Conclusions Our data suggest that an asymptomatic adrenal mass with homogeneous low attenuation (≦15 HU) and less than or equal to 4 cm indicates a nonhyperfunctioning adenoma, and no further examinations are necessary. CT attenuation value on non-contrast CT is the most important discriminatory factor.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01256711
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  • 3
    Electronic Resource
    Electronic Resource
    ESR spectrometer with a wide frequency range using a gyrotron as a radiation power source (1995)
    Springer
    International journal of infrared and millimeter waves 16 (1995), S. 293-305 
    Details
    ISSN: 1572-9559
    Keywords: gyrotron ; ESR ; wide frequency range
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The development of a high frequency electron spin resonance (ESR) spectrometer with a wide frequency range using a gyrotron as the radiation power source is described. GYROTRON FU-E, optimized for use in an ESR spectrometer in the millimeter wave range, was developed in Fukui University. In order to test the normal operation of the spectrometer, the ESR of two standard samples, single crystal and polycrystalline DPPH, has been measured, in the pulsed mode over the frequency range from 65 GHz to 135 GHz.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02085864
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  • 4
    Electronic Resource
    Electronic Resource
    Evaluation and application of a supercritical fluid extraction system using capillary supercritical fluid chromatography (1991)
    Weinheim : Wiley-Blackwell
    Journal of High Resolution Chromatography 14 (1991), S. 140-143 
    Details
    ISSN: 0935-6304
    Keywords: Supercritical fluid extraction, SFE ; Supercritical fluid chromatography, SFC ; Polycyclic aromatic hydrocarbon, PAR ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jhrc.1240140216
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  • 5
    Electronic Resource
    Electronic Resource
    Adhesion of polyethylene to metals. I. Effect of annealing on joint strength (1971)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 15 (1971), S. 511-511 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1971.070150225
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  • 6
    Electronic Resource
    Electronic Resource
    The epitaxial growth of gallium arsenide using triethylarsine (1989)
    New York, NY [u.a.] : Wiley-Blackwell
    Applied Organometallic Chemistry 3 (1989), S. 151-156 
    Details
    ISSN: 0268-2605
    Keywords: Epitaxial ; gallium arsenide ; decomposition ; triethylarsine ; semiconductor ; Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal decomposition of triethylarsine (TEAs) has been studied. It decomposes at a lower temperature than arsine (AsH3). The decomposition proceeds via a radical process at a temperature above 700°C. Epitaxial growth using TEAs has been investigated. A gallium arsenide (GaAs) layer with good morphology was obtained, but the layer was found to contain a considerable amount of carbon impurity originating from TEAs. The use of TEAs with 10% AsH3 or with 20% ammonia (NH3) apparently improves the quality of GaAs layer. A possible scheme for reducing carbon incorporation is discussed.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aoc.590030206
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  • 7
    Electronic Resource
    Electronic Resource
    The epitaxial growth of AlGaAs using highly purified trimethylaluminum (1991)
    New York, NY [u.a.] : Wiley-Blackwell
    Applied Organometallic Chemistry 5 (1991), S. 319-323 
    Details
    ISSN: 0268-2605
    Keywords: OMPVE ; epitaxy ; AlGaAs ; source gas ; trimethylaluminum ; impurity ; purification ; HEMT ; Chemistry ; Industrial Chemistry and Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Highly purified trimethylaluminum [(CH3)3Al] was prepared by reducing the contamination of volatile impurities such as organic silicon and dimethyl-aluminum methoxide [(CH3)2AlOCH3]. The concentration of methoxy group in (CH3)3Al was found to decrease considerably when (CH3)2Al was distilled in the presence of aluminum trihalide. Among the halides, purification efficiency increased in the order I〉Br〉Cl.High-quality AlGaAs layer and AlGaAs/GaAs modulation doped structures were grown by organometallic vapor-phase epiloxy (OMVPE) using the purified (CH3)3Al. Their electrical properties were discussed in relation to the volatile impurity in the source gas.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aoc.590050416
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  • 8
    Electronic Resource
    Electronic Resource
    The epitaxial growth of gaas using alkylarsine: Part 2. molecular orbital calculation (1991)
    New York, NY [u.a.] : Wiley-Blackwell
    Applied Organometallic Chemistry 5 (1991), S. 331-336 
    Details
    ISSN: 0268-2605
    Keywords: Molecular orbital ; calculation ; MOCVD ; source gas ; alkylarsine ; β-elimination ; Chemistry ; Industrial Chemistry and Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Semi-empirical molecular orbital calculations were carried out for the compounds (C2H5)3As, (C2H5)3Ga and RAsH2 (R = C2H5, i-C3H7, i-C4H9, and t-C4H9) by using the CNDO/2-U program, and their capability of β-elimination reaction is compared on the basis of the torsion energy to the transition state, electrostatic interactions and orbital overlapping between the central atom and the β-hydrogen, and bond order of the metal-carbon, and carbon-hydrogen bond. In the comparison of (C2H5)3As with (C2H5)3Ga, we found that the β-elimination of (C2H5)3As could hardly be expected to take place in the thermal decomposition. The capability of β-elimination would be smaller in C2H5AsH2 than that in (C2H5)3As. Moreover when the ethyl group is replaced by a t-butyl group in RAsH2, the β-elimination reaction appears to become more difficult and a large possibility for a radical process is suggested.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/aoc.590050418
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