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41.
T Toida M Shima S Azumaya T Maruyama H Toyoda T Imanari RJ Linhardt 《Canadian Metallurgical Quarterly》1997,787(1-2):266-270
The steady state DC endocochlear potential (EP) in young chicks shows a large decrease after acoustic overstimulation followed by a rapid recovery that parallels the recovery of threshold (Poje et al., Hear. Res. 82 (1995) 197-204). These results raise a question as to whether or not the EP could account for the hearing loss and make a significant contribution to the recovery of the threshold. In contrast to results in young chicks, we show that acoustic overstimulation, which causes extensive hair cell damage, does not cause a decrease in the steady state EP in adult chickens. However, there is a significant reduction in the negative EP seen during anoxia which persists even after 4 weeks of recovery. Thus, our results indicate that the steady state EP cannot account for the hearing loss observed in adult chickens. 相似文献
42.
43.
Ezaki M. Kumagai H. Toyoda K. Obara M. 《IEEE journal of selected topics in quantum electronics》1995,1(3):841-847
The surface modification of semiconductors by laser-induced surface electromagnetic wave (SEW) etching was investigated. With the novel etching method using a holographic exposure system, submicron periodic dot structures were fabricated directly on semiconductor substrates (n-InP, n-GaAs, and InGaAs-InP). Making use of laser polarization dependence in this etching system, a variety of surface modifications could be achieved on the semiconductors. In particular, in the case of using the s-polarization light, periodic submicron dot structures with a geometrical diameter down to 80 nm could be obtained directly using a single-step process without a mask. The InGaAs-InP dot structures were studied optically by means of photoluminescence spectroscopy, and the blue shift of the photoluminescence energy up to 5.36 meV was observed for the smallest dots, which displayed a lateral quantization 相似文献
44.
H Aida K Takakuwa H Nagata I Tsuneki M Takano S Tsuji T Takahashi T Sonoda M Hatae K Takahashi K Hasegawa H Mizunuma N Toyoda H Kamata Y Torii N Saito K Tanaka M Yakushiji T Araki K Tanaka 《Canadian Metallurgical Quarterly》1998,4(1):235-240
BACKGROUND: Stentless aortic xenografts are an important addition to the range of prosthetic valves. So far their use has been restricted to a limited number of study centers. This report summarizes the principal findings from the Second International Symposium on Stentless Bioprostheses. Attention is focused on the Toronto SPV and Freestyle valves recently approved by the United States Food and Drug Administration. METHODS: Stentless xenografts are used predominantly in elderly patients with aortic stenosis. Implant techniques are more complex than for stented valves, as reflected by longer ischemic and cardiopulmonary bypass times. The valves have been subjected to detailed serial echocardiographic assessment and clinical follow-up. RESULTS: The hemodynamic characteristics resemble those of the aortic homograft. There is a progressive increase in effective orifice area and decrease in transvalvular pressure gradients with time. Left ventricular mass index and wall thickness normalize between 6 and 12 months postoperatively. Left ventricular remodeling is accompanied by improved symptomatic status and a low incidence of valve-related complications. Limited comparative studies suggest important benefits over stented xenografts. Improved hemodynamics may translate into better bioprosthetic durability. CONCLUSIONS: Reproducible and reliable implant methods should be taught carefully, but the hemodynamic advantages are substantial. Stentless xenografts are ideal for the elderly patient with aortic stenosis. 相似文献
45.
Numata T. Irisawa T. Tezuka T. Koga J. Hirashita N. Usuda K. Toyoda E. Miyamura Y. Tanabe A. Sugiyama N. Takagi S. 《Electron Devices, IEEE Transactions on》2006,53(5):1030-1038
The authors have developed short-channel strained-silicon-on-insulator (strained-SOI) MOSFETs on silicon-germanium (SiGe)-on-insulator (SGOI) substrates fabricated by the Ge condensation technique. 35-nm-gate-length strained-SOI MOSFETs were successfully fabricated. The strain in Si channel is still maintained for the gate length of 35 nm. The performance enhancement of over 15% was obtained in 70-nm-gate-length strained-SOI n-MOSFETs. Fully depleted strained-SOI MOSFETs with back gate were successfully fabricated on SGOI substrate with SiGe layers as thin as 25 nm. The back-gate bias control successfully operated and the higher current drive was obtained by a combination of the low doping channel and the back-gate control. 相似文献
46.
Y. Mikami M. Mochizuki M. Toyoda Y. Hashiba T. Hasegawa S. Okita 《Welding International》2006,20(9):684-691
47.
K Kubota Y Bandai M Watanabe H Toyoda T Oka M Makuuchi 《Canadian Metallurgical Quarterly》1996,43(7):147-151
A 71-year-old man with a tumorous lesion of the common bile duct is presented. Although histological examination of tumor biopsy specimens taken at the time of duodenoscopy or percutaneous transhepatic choledochoscopy showed mucosal hyperplasia, cancer could not be ruled out; therefore, the patient underwent pancreatoduodenectomy. However, histology showed nodular mucosal hyperplasia and an ectopic pancreas adjacent to the papilla of Vater, which was suspected to have contributed to the development of the lesion by stimulating the mucosa of the papilla and the distal common bile duct. 相似文献
48.
M Niki H Isozaki M Toyoda T Ishibashi K Fujii E Nomura H Mabuchi M Nakamura K Nishiguchi N Tanigawa 《Canadian Metallurgical Quarterly》1998,45(24):2458-2463
BACKGROUND/AIMS: Hepatocyte growth factor (HGF) is a stromally derived protein growth factor that modulates epithelial cell proliferation and motility. HGF may therefore be involved in tumor progression. METHODOLOGY: We measured the immunoreactive (ir)-HGF concentration in the sera of 56 patients with human gastric carcinoma, using an enzyme-linked immunosorbent assay and evaluated its association with clinical and histopathologic factors. Clinical stages were classified in accordance with The General Rules for TNM Classification (International Union Against Cancer). RESULTS: The serum hHGF concentrations from patients with gastric carcinoma significantly increased with increasing pathologic tumor grades. Also, there were significantly higher concentrations in patients with nodal metastasis compared to patients without metastasis. The serum hHGF concentrations in patients with liver metastasis were significantly higher than in patients without liver metastasis. CONCLUSIONS: These data show that the serum hHGF concentration is elevated in gastric carcinoma patients with liver and nodal metastasis. In multivariate analysis, the serum hHGF concentration was found to be the most important independent factor in predicting overall survival. Thus, the current results suggest that HGF may be important in the progression and metastasis of gastric carcinoma. 相似文献
49.
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
50.