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101.
T Shimazu T Yoshioka Y Nakata K Ishikawa Y Mizushima F Morimoto M Kishi M Takaoka H Tanaka A Iwai A Hiraide 《Canadian Metallurgical Quarterly》1997,42(4):641-646
BACKGROUND: Crush syndrome is a form of traumatic rhabdomyolysis characterized by systemic involvement, in which acute renal failure is potentially life-threatening. METHODS: Clinical and laboratory data of 14 crush-syndrome patients transferred to a tertiary emergency department after the Hanshin-Awaji earthquake were analyzed. The patients were buried under collapsed houses for the average of 6.7 +/- 5.7 (SD) hours (range, 1 to 24 hours). They were referred to us 6 to 250 hours after the earthquake. RESULTS: Of those who arrived at our institution within 40 hours, 25% (two of eight) developed renal failure, whereas all six patients who arrived after 40 hours developed renal failure. Peak serum creatine kinase ranged from 6,677 to 134,200 U/L (51,674 +/- 41,776). Renal failure was highly associated with massive muscle damage (serum creatine kinase above 25,000 U/L) and insufficient initial fluid resuscitation (below 10,000 mL/2 days). CONCLUSIONS: Prompt and adequate, if not massive, fluid resuscitation is the key to preventing renal failure after such injury. 相似文献
102.
T Mitsuhashi T Ikata K Morimoto T Tonai S Katoh 《Canadian Metallurgical Quarterly》1994,32(8):524-530
Arachidonate metabolites have many kinds of bioactivities. Thromboxane A2 (TXA2) stimulates platelet aggregation and vasoconstriction, whereas prostaglandin I2 (PGI2) antagonises its activities. Thromboxane B2 (TXB2) and 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) are determined in biological materials. Production of TXB2, 6-keto-PGF1 alpha and leukotriene C4 (LTC4), which have potent vascular permeability, was measured by radioimmunoassay in experimental spinal cord injured animals. TXB2 level in the rat spinal cord reached a peak concentration of 133.6 +/- 3.8 pmol/g cord, and 6-keto-PGF1 alpha increased to 26.2 +/- 11.7 pmol/g cord 5 minutes after the injury. There was good correlation between TXB2 production and vascular damage as monitored by fluorescein uptake. When OKY-046 ((E)-3-[4-(1-imidazolylmethyl) phenyl]-2-propenoic acid), which selectively inhibits TXA2 synthetase activity, was administered 10 minutes before injury, the increase in TXB2 production was inhibited by more than 80%, but the degree of vascular damage was reduced by only 40%. In the guinea pig spinal cord, LTC4 levels reached a peak concentration of 2.2 +/- 0.4 pmol/g cord 10 minutes after compression, while that of TXB2 reached 146.8 +/- 6.2 pmol/g cord. The increased production of TXB2 was correlated with the degree of compression injury while that of LTC4 production did not. These findings suggest that vasoactive eicosanoids, TXA2, PGI2 and LTC4, play important roles in secondary damage following spinal cord injury, although their roles may be different among species of animals. 相似文献
103.
Morimoto M. Orihara K. Mutoh N. Toyoda A. Ohbo M. Kawakami Y. Nakano T. Chiba K. Kawai S. Hatano K. Arai K. Nishimura M. Nakashiba Y. Kohno A. Akiyama I. Teranishi N. Hokari Y. 《Electron Devices, IEEE Transactions on》1995,42(1):50-57
A 1-inch 2-million pixel FIT-CCD image sensor for HDTV has been developed, which features a tungsten photo-shield and horizontal CCD (H-CCD) shunt wiring. Tungsten photo-shield, which has low reflectance and good step coverage characteristics, reduces smear level to -110 dB, combined with a frame-interline-transfer (FIT) scheme. The tungsten photo-shield also acts as a shunt busline, supplying transfer pulses to vertical CCD (V-CCD) electrodes, so that a 1.2×10ˆ5 electron charge handling capability is obtained at a frame transfer frequency of 1 MHz. Newly developed H-CCD shunt wiring suppresses vertical line pair FPN, even with smaller transfer pulse amplitudes. H-CCD shunt wiring also helps reduce power consumption in the H-CCD by 2/3 as compared to that achieved with conventional wiring 相似文献
104.
Koichi Kikuta Katsuhiko Takagi Shin-ichi Hirano 《Journal of the American Ceramic Society》1999,82(6):1569-1572
The photoreaction of metal-organic compounds prepared by the chemical modification of metal alkoxides was investigated for the patterning of ceramic films. The chemical stability and photoreactivity of these compounds were found to be greatly influenced by the kind of chemical additive applied during the syntheses of the precursor solutions. In this study, the photoreaction of the precursor thin films prepared by the addition of alkanolamines was achieved by tuning the wavelength of the incident UV light. The decomposition of the organic moieties of the percursors was clearly observed in IR spectra during UV irradiation. Furthermore, the spectrum of the titania precursor film in the visible and ultraviolet regions (UV-vis) changed in accordance with the irradiation time. The photolithography of the titanium precursor pattern was successfully achieved by means of these techniques. 相似文献
105.
Kazuhiro Ema Hidemi Shigekawa Shin-ichi Hyodo 《Journal of the American Ceramic Society》1984,67(6):104-C
During strength measurements on plastic-coated optical glass fibers, the positions of fracture origins were determined by an acoustic technique. For samples other than those in which fracture was initiated at or very near the fixed ends, Weibull plots of the strength data exhibited a single-mode distribution with low variability (m=20 to 25, corresponding to a coefficient of variation of 6.6 to 10.6%). 相似文献
106.
Vilas Wuwongse Shigenobu Kobayashi Shin-ichi Iwai Atsunobu Ichikawa 《Computers in Industry》1983,4(4):381-394
When designing linear control systems, one of the most difficult problems is that the designer almost has no theoretical basis for the determination of proper parameters in order to obtain a system with desired specifications. Poles and directions of eigenvectors in the pole assignment method or weighting matrices of the quadratic criterion function in the optimal regulator method are such parameters. The designer has to determine them by trial-and-error using computer simulation. The purpose of this paper is to propose an approach to helping determine proper parameters in linear control system design by the state space methods. In the case where the desired specifications are not given explicitly, the approach applies an interactive optimization method called the Interactive Simplex method to search the most suitable parameters directly in the parameter space. But, if the specifications are given explicitly, the design problem can be formulated as a multiobjective optimization problem. In this case, weights which indicate relative importance of different specifications are introduced and the Interactive Simplex method is applied in the weight space to indirectly find the most appropriate parameters. The approach is implemented as part of a CAD system. The designer has only to make pairwise comparisons of response curves which are shown on a graphics display terminal in order to obtain the most preferred control system. Two illustrative examples are demonstrated to indicate the efficiency of the approach. 相似文献
107.
The transepithelial transport and metabolism of two model peptides, glycyl-D-phenylalanine (Gly-D-Phe) and glycyl-L-phenylalanine (Gly-L-Phe), across primary cultured monolayers of rat alveolar epithelial cells were studied. These tight monolayers (> 2000 omega-cm2) exhibited type I pneumocyte morphological and phenotypic characteristics. A reverse-phase HPLC was used to monitor the appearance of parent dipeptides and their metabolites (D- or L-Phe) in the receiver fluid. The apparent permeability coefficient (Papp) for Gly-D-Phe was about 1.6 x 10(-7) cm/sec at both 1 and 10 mM and in both the apical-to-basolateral (AB) and the basolateral-to-apical (BA) directions. In contrast, the Papp of Gly-L-Phe at 1 mM was about two times higher than that at 10 mM in the AB direction. The Papp of Gly-L-Phe in the BA direction at either concentration was about the same (about 1.4 x 10(-7) cm/sec). Whereas no metabolite was detected during Gly-D-Phe transport, the proportions of a metabolite, L-Phe, observed at 4 hr in the basolateral receiver fluid for 1 and 10 mM apical donor Gly-L-Phe accounted for 83 and 77% of the estimated total Gly-L-Phe (i.e., L-Phe+Gly-L-Phe), respectively. The corresponding values in the BA direction were 40 and 19% of the estimated total Gly-L-Phe in the apical receiver reservoir. Metabolism of Gly-L-Phe was significantly reduced in the presence of 3 microM actinonin (an inhibitor relatively specific for aminopeptides M) in the apical but not the basolateral fluid.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
108.
Y Watanabe S Morimoto T Adachi M Kashimura T Asaka 《Canadian Metallurgical Quarterly》1993,46(4):647-660
Although erythromycin A contains five hydroxyl groups, regioselective methylation at the C-6 hydroxyl group was achieved to the extent of 90% when a 9-O-substituted erythromycin A 9-oxime was employed as substrate. The methylation and its selectivity are dependent on an O-protecting group at the 9-oxime, solvent, base, and methylating reagent. In particular, the use of a polar aprotic solvent is indispensable for the methylation. Among the 9-oxime derivatives, 2'-O,3'-N-bis(benzyloxycarbonyl)-N-demethylerythromycin A 9-[O-(2-chlorobenzyl)oxime] was the most important intermediate for the synthesis of clarithromycin (6-O-methylerythromycin A). 相似文献
109.
The deflector shows excellent loss modulation characteristics in a laser cavity under large signal operation. The mode locker is capable of generating very short optical pulses comparable to those obtained by passive mode locking. In experiments, an LiTaO3 double-prism deflector is used as the mode locker for an Nd:glass laser. As a result, stable 6-ps pulses are obtained 相似文献
110.