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111.
T Seo K Yamao T Hayashi C Kotake T Toda K Kobayashi Y Yokota 《Canadian Metallurgical Quarterly》1996,28(4):183-189
Intravascular ultrasound (IVUS) imaging was used to measure internal luminal area immediately after percutaneous transluminal coronary angioplasty (PTCA) in 83 patients (59 males, 24 females, mean age 63 +/- 12 years) with angina pectoris to determine the need for additional intervention. The effectiveness of these interventions to prevent restenosis was also studied. Thirty-five patients (42%) with insufficient dilatation revealed an internal luminal area less than 5 mm2 or luminal stenosis greater than 60% as evaluated by IVUS imaging following the procedure. The luminal area increased from 4.5 +/- 1.1 to 7.9 +/- 2.8 mm2 and the percentage luminal stenosis improved from 66 +/- 9% to 54 +/- 9% in patients who underwent further dilatation with a larger size balloon, longer dilatation time, directional coronary atherectomy, or stenting. The insufficient dilatation group exhibited hard plaque and calcification more frequently than in the other group (48 patients, 58%) in whom sufficient dilatation of the target lesion was achieved. The incidence of restenosis in the sufficient dilatation group was 25%, compared to 33% of the patients receiving additional treatment after IVUS imaging and 42% in the 192 patients who underwent PTCA without IVUS imaging. IVUS imaging is a useful method for evaluation of complex luminal morphology to decrease the incidence of restenosis and for determination of the end point and the extent of dilatation required. 相似文献
112.
H Kitagawa T Hayashi Y Mitsumoto N Koga Y Itoyama K Abe 《Canadian Metallurgical Quarterly》1998,29(7):1417-1422
BACKGROUND AND PURPOSE: Glial cell line-derived neurotrophic factor (GDNF) plays important roles in the survival and recovery of some mature neurons under pathological conditions. However, the effect of GDNF in ameliorating ischemic brain injury has not been well documented. Therefore, we investigated a possible effect of GDNF on the changes of infarct size, brain edema, DNA fragmentation, and immunoreactivities for caspases after permanent middle cerebral artery occlusion (MCAO) in rats. METHODS: For the estimation of ischemic brain injury, we calculated the infarct size of MCA region and also measured the brain water content as edema formation at 24 hours after the MCAO. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin in situ nick labeling (TUNEL) staining was performed for the detection of DNA fragmentation. Immunoreactivities for caspase-1 (ICE), caspase-2 (Nedd-2), and caspase-3 (CPP32) were stained. RESULTS: Both infarct size and brain edema after permanent MCAO were significantly reduced by topical application of GDNF (48% and 30% decreases, P=0.01). TUNEL staining and immunoreactivities for caspases were markedly induced at 12 hours after permanent MCAO in the vehicle-treated animals. However, the spatial distribution of those immunohistochemically positive cells was dissociative in each caspase. Induction of TUNEL staining and immunoreactivities for caspases-1 and -3 was greatly reduced with GDNF treatment, whereas the reduction of caspase-2 staining was only minimum. CONCLUSIONS: These data suggest that the reduction of infarct size and brain edema by GDNF was greatly associated with the reduction of DNA fragmentation and apoptotic signals predominantly through caspases-1 and -3 cascades. 相似文献
113.
Miyuki Hayashi Masahiro Susa Toshio Maruyama Kazuhiro Nagata 《Journal of Electronic Materials》1995,24(8):983-989
The annealing of 20CaO·20SiO2·7Fe2O3·6FeO glasses at 973K in vacuo produced clusters of iron oxide, the shape of which was nearly spherical and the diameter distributed in the narrow range 25–115Å. The phase of clusters was identified to be Fe3+(Fe3+ poststagger|1.30Fe2+ poststagger|0.55V0.15)·O4 in the inverse spinel structure based upon the Mössbauer spectra and x-ray diffraction profiles. The clusters exhibited superparamagnetism and their effective anisotropy energy constant was inversely proportional to the cluster diameter. The magnetization of the glasses measured by a vibrating sample magnetometer was 7.2 × 10-6 Wbmkg-1 at 10 kOe at room temperature and smaller than the value calculated assuming that the whole clusters have superparamagnetism. These results suggest the pinning of spins near the cluster surface. 相似文献
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Wataru Sakamoto Mio Yamada Naoya Iizawa Yu-Ki Mizutani Daichi Togawa Koichi Kikuta Toshinobu Yogo Takashi Hayashi Shin-Ichi Hirano 《Journal of Electroceramics》2004,13(1-3):339-343
Neodymium-modified Bi4Ti3O12, (Bi, Nd)4Ti3O12 (BNT) ferroelectric thin films have been prepared on Pt/TiOx/SiO2/Si substrates using metal-organic precursor solutions by the chemical solution deposition method. The BNT precursor films crystallized into the Bi layered perovskite Bi4Ti3O12 (BIT) as a single-phase above 600C. The synthesized BNT films revealed a random orientation having a strong 117 reflection, whereas non-substituted BIT thin films exhibited a random orientation with strong 00l diffractions. Among Bi4 – xNdxTi3O12 [x = 0.0, 0.5, 0.75, 1.0] thin films, Bi3.25Nd0.75Ti3O12 thin films showed a well-saturated P-E hysteresis loop with the highest Pr (22 C/cm2) and a low Ec (69 kV/cm) at an applied voltage of 5 V. The Nd-substitution with the optimum amount for the Bi site in the BIT structure was effective not only for promoting the 117 preferred orientation but also for improving the microstructure and ferroelectric properties of the resultant films. 相似文献
118.
A continuous vacuum dryer for energy saving has been developed in order to produce dried foods without heat denaturation in the products. This drying method is suitable for heat sensitive I and highly viscous foods and can dry to 1 to 4% in moisture content with good quality at around 40°C in product temperature andin 5 -10 min a drying time. Feed material with high viscosity has to I have uniform distribution on the belt in the vacuum chamber to I keep a constant drying for which a special feed nozzle has been developed after considerabl~ testing. Heat transfer on the wet material in the dryer has occurred by both conduction and radiation because of the design so that the thermal efficiency in 相似文献
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Polymer film-type channel electron multipliers (CEMs) were developed and their characteristics investigated in comparison with bulk-type flexible CEM. As film-type CEMs, a paint-coating-type CEM and a solvent-etching-type CEM were fabricated. The paint-coating-type CEM is made by coating a “paint” which is prepared by dissolving in a solvent an electronically conductive polymeric composition having a high secondary electron emission yield. Up to the present study the mean gain of the film-type CEM, in spite of the lower resistivity of the dynode, seems to be slightly more dependent on the count rate than that of the bulk-type CEM made of the same material. However, the convenience of fabricating the dynode film by coating the dynode-forming paint on the internal surface of any shaped tube or a flexible polymer tube would overcome the slight disadvantage mentioned above. 相似文献