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91.
H Ohashi T Kawai Y Tsutsumi K Ueyama Y Kawase K Ueyama M Ohnaka 《Canadian Metallurgical Quarterly》1997,50(4):263-7; discussion 267-9
Combined surgery in 6 cases who had coronary artery disease and thoracic aortic disease simultaneously was analyzed. Case # 1 had ascending aortic replacement under deep hypothermic circulatory arrest because of iatrogenic aortic dissection caused by aortic clamp during the routine coronary artery bypass grafting (CABG). Case # 2 had DeBakey type II chronic dissection. Case # 3 had type I aortic dissection 4 years after the initial CABG. Both case # 2 and # 3 had ascending aortic replacement under retrograde cerebral perfusion along with CABG. Transverse aortic replacement was performed in case # 4, # 5 and # 6 under selective cerebral perfusion along with CABG. Case # 4 was associated with ascending-transverse aortic aneurysm. Case # 5 had aortitis syndrome complicated with severe coronary ostial stenosis and cervical branch stenosis. Case # 6 also had aortitis syndrome, severe coronary ostial stenosis, heavily calcified ascending-transverse aorta, and mitral and aortic regurgitation. This case had mitral and aortic valve replacement additionally. Case # 2 died of low cardiac output syndrome and multi-organ failure postoperatively. Case # 4 did not recover from profound shock that followed the preoperative acute myocardial infarction. The problems of low cardiac output syndrome caused by long interval of ischemic cardiac arrest, and also the problems of proximal anastomotic site of saphenous vein grafts were discussed. 相似文献
92.
T Suzuki E Ohtaki T Murai M Imai S Kawai M Kitaoka K Kitahara R Okada S Suzuki 《Canadian Metallurgical Quarterly》1997,61(3):272-274
Idiopathic restrictive cardiomyopathy (RCM) is rare. Even today little is understood of its etiology or underlying mechanisms, and definitive diagnostic criteria are lacking. In this report, we describe a case of idiopathic RCM in a young Japanese woman who died while awaiting cardiac transplantation during the 5-year course of the disease. Rare pathologic findings of diffuse perimyocytic fibrosis were revealed at autopsy. 相似文献
93.
94.
Maki Kawai 《Bulletin of Materials Science》1997,20(6):769-776
Adsorption and desorption of CO on Ni(100) and Pt(111) surfaces are presented. At the thermodynamic equilibrium, the site occupation between the terminal and the bridged sites are described with the free energy of the system, including the vibrational entropy. Adsorption of CO onto a cold surface as 20 K has also been studied by infrared reflection absorption spectroscopy (IRAS). The occupation ratio of bridged CO to terminal CO species on Ni(100) at 20 K ranges from ~ 2·8 to 0·7 at the total coverage from 0·003 to 0·15 ML. Such strong coverage dependence of the occupation ratio even at small coverages suggests that the interaction between CO molecules operates at relatively long range (> 10 Å). The isotope experiments suggest that there is substantial interaction between preadsorbed (accommodated) CO species and incoming (mobile) CO species. Desorption process is also affected by the interaction between the adsorbed CO and the incoming species. The effect of temporal bimolecular CO interaction on the desorption kinetics is also discussed. 相似文献
95.
96.
Hibi Y Asai K Arafuka H Hamajima M Iwama T Kawai K 《Journal of Bioscience and Bioengineering》2011,111(5):547-549
La(3+) and not Ca(2+) increases methanol dehydrogenase (MDH) activity in Methylobacterium radiotolerans NBRC15690. La(3+)- and Ca(2+)-MDH-like proteins were found to be homodimeric (α(2)) and heterotetrameric (α(2)β(2)), respectively. N-terminal amino acid sequences of these proteins revealed that La(3+)- and Ca(2+)-MDH-like proteins were encoded by xoxF and mxaFI, respectively. 相似文献
97.
Understanding of the molecular relationships in carbohydrate-protein interactions provides useful information on biological processes in living organisms and is also helpful for development of potent biomedical agents. Herein, the interaction unbinding force between GM1 pentasaccharide and Vibrio cholera toxin (ctx) proteins was measured using atomic force microscopy (AFM), which enabled us to determine the interaction of ctx holotoxin (ctxAB) with GM1 and the interactive formation. First, the interaction force measured between A and B subunits (ctxA-ctxB) was 184.2 ± 4.5 pN, and the unbinding forces were evaluated to confirm the role of ctxA in ctxAB complex formation and were determined to be 443.7 ± 7.5 and 535.7 ± 25.9 pN for GM1-ctxB and GM1-ctxAB complexes, respectively. The force difference of ~90 pN between GM1-ctxB and GM1-ctxAB might be due to the formation of the cholera toxin complex. Importantly, from the analogue analyses, we understand how structural and binding positional differences in complex carbohydrates affect the interaction with protein and surmise that the GM1-ctxAB complex makes a "two-finger grip" formation through the conformational change of a flexible carbohydrate. In conclusion, using AFM force analysis, we successfully quantified and characterized the interactive configuration of carbohydrate-protein molecules. 相似文献
98.
Takashi Ishikawa Masamichi Matsushima Youichi Hayashi 《Journal of Materials Science》1985,20(11):4075-4083
Uniaxial tensile tests of unidirectional carbon-epoxy coupons are conducted in the longitudinal direction. It is observed that the longitudinal modulus increases with axial stress or strain up to the intermediate level of tension. A fractional constitutive relation with a quadratic denominator is derived by the method of the theory of non-linear elasticity. This equation adopting the estimated higher-order compliance coefficients exhibits an excellent agreement with the experimental results. An empirical strain-based equation is also proposed as a simpler alternative. Averaging formulae for both types of relation are provided for a practical application. The present phenomenon includes the behaviour in a low-stress region discovered by some early work. The consideration of the present non-linear behaviour improves the correlation between theory and experiments in stress-strain relationships of fabric composites with carbon fibres. 相似文献
99.
T Kawai 《Canadian Metallurgical Quarterly》1998,46(11):1083-1086
BACKGROUND: Recent investigation into the push-pull effect (PPE), the reduction of +Gz tolerance when preceded by less than +1 Gz, has focused on centrifuge studies to demonstrate the presence of adverse cardiovascular responses. Maneuvers found to cause the Push-Pull Effect (PPEM) have not been studied previously in U.S. Air Force (USAF) fighter aircraft. The frequency of and extent to which PPEMs are performed in fighter aircraft are unknown. METHODS: Head-up display (HUD) videotapes from F-15 and F-16 air combat training missions were reviewed for the presence of PPEMs. The frequency of engagements containing PPEMs and the magnitude of the Gz profiles were noted. RESULTS: PPEMs were found in 11 to 67%, of engagements reviewed, depending on the nature of the training mission, with an overall average of 32%. The PPEMs that were observed contained segments of less than +1 Gz, ranging on average from 0.0 to 0.5 Gz for an average of 3.5 to 5 s duration. CONCLUSIONS: PPEMs are present in air combat training missions performed by today's USAF fighter aircraft and represent an operationally significant source of risk for accidents. These findings support continued research into the physiologic response to PPE and the development of countermeasures. 相似文献
100.
Kawai S. Morimoto M. Mutoh N. Teranishi N. 《Electron Devices, IEEE Transactions on》1995,42(4):652-655
Photo response in CCD image sensors with Vertical-Overflow-Drain (VOD) was analyzed in an attempt to discover a way to lessen the photo response rise that accompanies increasing incident light intensity in the saturation region. A photo response analysis based on transistor I-V characteristics revealed that the extent of rise in the saturation region is uniquely determined by the non-ideality factor and temperature. Calculation of the non-ideality factor and its dependence on P-well impurity concentration and layer thickness further revealed that fabrication of P-wells with lower impurity concentrations and thicker layers would be effective in suppressing photo response rise 相似文献