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131.
Kumaki S. Takata H. Ajioka Y. Ooishi T. Ishihara K. Hanami A. Tsuji T. Watanabe T. Morishima C. Yoshizawa T. Sato H. Hattori S. Koshio A. Tsukamoto K. Matsumura T. 《Solid-State Circuits, IEEE Journal of》2002,37(3):450-454
A scalable single-chip 422P@ML MPEG-2 video, audio, and system encoder LSI for portable 422P@HL system is described. The encoder LSI is implemented using 0.13-μm embedded DRAM technology. It integrates 3-M logic gates and 64-Mb DRAM in an area of 99-mm2. The power consumption is suppressed to 0.7 W by adopting a low-power DRAM core. It performs real-time 422P@ML video encoding, audio encoding, and system encoding with no external DRAM. Furthermore, the encoder LSI realizes a 422P@HL video encoder with multichip configuration, due to its scalable architecture. This results in a PC-card size 422P@HL encoder for portable HDTV codec system 相似文献
132.
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
133.
134.
C Yamashita Y Tsuji M Yoshimura S Kozawa M Okada 《Canadian Metallurgical Quarterly》1994,24(11):1019-1022
Composite graft replacement of the ascending aorta and aortic valve has now become a safe surgical procedure; however, early and late complications still frequently occur. Anastomotic dehiscence after a composite graft replacement is one potentially lethal complication. We herein report two cases of a pseudoaneurysm caused by dehiscence of the right coronary anastomosis, and the proximal aortic anastomosis. A follow-up with an echocardiogram and computed tomography scan was found to be very useful and accurate. We thus successfully treated two cases of pseudoaneurysm using either Bentall's or Carbrol's procedures. 相似文献
135.
K Yamamoto S Kusachi Y Ninomiya M Murakami M Doi K Takeda T Shinji T Higashi N Koide T Tsuji 《Canadian Metallurgical Quarterly》1998,30(9):1749-1756
Biglycan, a small dermatan sulphate proteoglycan, has been postulated to interact with other components of the extracellular matrix (ECM), specifically collagens. We hypothesized that biglycan messenger ribonucleic acid (mRNA) is increased in the myocardial infarct zone. Biglycan mRNA expression after acute myocardial infarction (AMI) in rats was determined with the use of Northern blotting and in situ hybridization, and its expression pattern was compared to that of type I collagen mRNA [alpha1(I) collagen]. The left coronary artery was ligated in male Sprague-Dawley rats, and the hearts were excised on days 2 and 7. The Northern blot analysis demonstrated that expression of biglycan mRNA in the infarct on days 2 and 7 were 4.0- and 6.8-fold higher, respectively, compared to the sham-operated hearts. The in situ hybridization revealed intense signals for both biglycan and alpha1(I) collagen mRNA on day 2 in the spindle-shaped mesenchymal cells located between the surviving myocytes in the infarct peripheral zone. On day 7, biglycan mRNA signals were observed in the interior of the infarct around the infarct granulation tissue, a distribution that was essentially the same as that of alpha1(I) collagen. These results demonstrated that the increases in the infarct biglycan mRNA expression produced by mesenchymal cells (presumably myofibroblasts and fibroblasts) was closely co-localized with that of type I collagen mRNA, indicating that biglycan contributes to the infarct healing processes. 相似文献
136.
D Kobayashi N Watanabe H Sasaki T Okamoto N Tsuji T Sato N Yamauchi Y Niitsu 《Canadian Metallurgical Quarterly》1998,76(4):552-555
The liver is an important target organ for gene therapy but its mitotic quiescence makes it resistant to integrative gene transfer. Retrovirus-based vectors integrate into liver cells in vivo but require the liver to be primed before transduction; experimentally a 70% hepatectomy is commonly used to stimulate regeneration, rendering the liver susceptible to transduction during the resulting wave of cell proliferation. Our aim was to develop a clinically acceptable method of inducing hepatocyte replication before in vivo retroviral gene transfer which is both simple and effective. We have used the physiological hormone tri-iodothyronine (T3) to stimulate hepatocyte replication. A single dose of T3 (400 micrograms/100 g bw) was given subcutaneously to euthyroid rats. This produced a labelling index of 31.7% in the hepatocyte population without histological or biochemical evidence of preceding liver damage. Following T3 administration the rat livers were transfected in vivo with an amphotropic retrovirus, TELCeB/AF-7 which encodes the beta-galactosidase reporter gene together with a nuclear localisation signal. Transgene expression was noted only within the liver where 1.3% of hepatocytes expressed the beta-galactosidase enzyme. This compared to 5.2% of hepatocytes transduced following a 70% hepatectomy, and 0.02% in animals receiving neither T3 nor partial hepatic resection before transduction. T3 administration is a simple way to prime the liver before in vivo retroviral vector-based gene transfer. 相似文献
137.
Y Imai A Nishiyama T Ohkubo I Tsuji K Nagai N Kikuchi H Satoh S Hisamichi 《Canadian Metallurgical Quarterly》1997,15(8):827-838
OBJECTIVE: To investigate factors affecting the nocturnal decrease in blood pressure. DESIGN: A cross-sectional study of 823 community-based untreated subjects aged > 20 years. Screening and ambulatory blood pressures were measured and the effects of age and the ambulatory blood pressure on the nocturnal decrease were examined. RESULTS: The magnitude of the decrease and the percentage decrease in the nocturnal blood pressure increased with increasing daytime ambulatory blood pressure and decreased with increasing night-time ambulatory blood pressure. Although the magnitude of the nocturnal decrease in blood pressure increased with increasing daytime blood pressure, the nocturnal blood pressure levels in hypertensives were still higher than those in normotensive subjects. The magnitude decreased with increasing age for men but not for women, whereas the percentage decrease decreased with increasing age both for men and for women. The SD of the 24 h blood pressure correlated strongly to the magnitude of the nocturnal decrease (systolic blood pressure r = 0.62, P < 0.0001; diastolic blood pressure r = 0.52, P < 0.0001), suggesting that the SD of the 24 h blood pressure is representative of the nocturnal decrease. A minimal nocturnal decrease was observed frequently in elderly normotensive men but infrequently in hypertensive individuals from the general population. A marked nocturnal decrease was observed frequently in hypertensive women aged > 70 years. CONCLUSION: Although the magnitude of the nocturnal decrease in blood pressure increased with increasing daytime blood pressure, the nocturnal blood pressure levels increased with increasing daytime ambulatory blood pressure. Therefore, the blood pressure in hypertensive subjects should essentially be lowered throughout the 24 h period. A marked nocturnal decrease in blood pressure in some elderly hypertensive women was observed without treatment. The nocturnal blood pressure levels of such subjects should be considered during treatment. 相似文献
138.
A new formulation of the finite-element method to analyze nonreciprocal waveguides in magneto-photonic crystals (MPCs) is proposed. Accurate solutions of light propagations for two different directions are obtained by the asymmetrical input condition. As numerical examples, the performance of a waveguide-type optical isolator in MPCs designed by the eigenmode analyses is confirmed by using this method. Subsequently, an effective way to enhance the nonreciprocity of the optical isolator is shown. 相似文献
139.
Shirai M. Arimoto H. Watanabe K. Taike A. Shinoda K. Shimizu J. Sato H. Ido T. Tsuchiya T. Aoki M. Tsuji S. Sasada N. Tada S. Okayasu M. 《Electronics letters》2003,39(9):733-735
A novel travelling-wave electroabsorption optical modulator, electrically matched for 50 /spl Omega/ loads of driving circuit drivers, was developed. The scattering parameter of electric reflection (S/sub 11/) from this modulator is less than -20 dB at 20 GHz. It can thus enable a 40 Gbit/s, 2 km SMF transmission with a 0.3 dB penalty at a 1.3 /spl mu/m wavelength. 相似文献
140.
The Swedish interactive thresholding algorithm (SITA) is a new thresholding algorithm that aims to obtain the visual fields of the same quality in a shorter examination time than the conventional up-and-down method. We investigated the correlation between the threshold values obtained by SITA and the conventional thresholding algorithm in 30 glaucoma patients. The results of two types of SITA, i.e., SITA accurate and SITA fast, showed a significant correlation with those of the conventional method (r = 0.855, p < 0.0001 and r = 0.833, p < 0.0001, respectively). There was no statistical relation between the mean deviation (MD) of the conventional method and the difference between MD values of the conventional method, and SITA accurate and SITA fast. The examination time of SITA accurate and SITA fast was 50% and 31% shorter, respectively, than that of the conventional method. The difference in threshold of each test point in the conventional and SITA methods was minor except in one with a deep relative defect. These results indicate that SITA can be useful for detecting glaucomatous visual field defects in a shorter time. 相似文献