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21.
M Kogushi H Tanaka I Ohtsuka T Yamada H Kobayashi T Saeki M Takada H Hiyoshi M Yanagimachi T Kimura S Yoshitake I Saito 《Canadian Metallurgical Quarterly》1996,124(2):203-210
E5324, n-butyl-N'-[2-[3-(5-ethyl-4-phenyl-1H-imidazol-1-yl)propoxy]-6- methylphenyl]urea, a novel and potent inhibitor of acyl-CoA:cholesterol acyltransferase (ACAT), was evaluated for its anti-atherosclerotic and lipid-lowering effects in Watanabe heritable hyperlipidemic (WHHL) rabbits. At 3 months of age, 40 male WHHL rabbits were divided into 4 groups. The rabbits were fed a standard rabbit chow (control group), or standard rabbit chow containing E5324 (0.1% or 0.02%) or 1% probucol for 16 weeks. Even the high dose of E5324 did not lower the plasma total cholesterol levels throughout the experiment. Probucol slightly reduced the plasma cholesterol levels, and showed anti-atherosclerotic activity, i.e., reductions of atherosclerotic plaque formation and cholesterol content in the aorta. Although E5324 did not lower plasma cholesterol, atherosclerotic plaque formation in the aortic arch and thoracic aorta was reduced (by about 34% and 41%, respectively, at the high dose; P < 0.05). Cholesterol content in the aortic arch and thoracic aorta was also reduced (by about 59% and 62% at the high dose, respectively) compared with the control. These results suggest that E5324 acts directly on the arterial wall through ACAT inhibition, and prevents the progression of atherosclerosis in WHHL rabbits. 相似文献
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Narrow and low-loss YBa2Cu3O7-δ (YBCO) coplanar lines, which can be used in multichip module technology for future high-density and high-speed digital circuits, have been developed. Etch-back planarization and a patterning process combining Ar-ion milling and wet-etching enabled us to form an 18-cm-long 5-μm-wide YBCO coplanar line without electrical shorts, even for the narrow spacing of 2.5 μm. The surface resistance of this line was kept at a level comparable to that of 10- or 25-μm-wide YBCO coplanar lines and also comparable to that of unpatterned films. This indicates successful fabrication of the 5-μm-wide YBCO coplanar line without notable loss increase resulting from process damage. The 5-μm-wide line showed a low-transmission loss of 0.49 dB at 10 GHz and 55 K. This level of loss is similar to that in Cu coaxial cables. No significant increase in transmission loss was observed up to an input power level of 16 mW at 10 GHz and 55 K. This input power is comparable to the power-handling capability required for transmitting high-speed digital signals through the lines with characteristic impedance of 50 Ω. These results show that the narrow 5-μm-wide YBCO coplanar line has great potential for high-density and high-speed digital circuits 相似文献
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Summary Propylene polymerization was performed with a highly active MgCl supported TiCl4 in conjunction with Et3Al and ethyl benzoate (EB). The obtained polypropylene sample was separated into four fractions by successive extraction with pentane, heptane and trichloroethylene (trichlene). Yield, Mn, Tm and microtacticity of each fraction were determined, and the effects of the concentration of EB on these items of results were investigated. It has been found that EB enhances yield, Mn and stereospecificity of trichlene insoluble (the most stereospecific) fraction, and in contrast, it decreases rapidly yields of other three fractions without changing the character of the polymers. From these findings, the functions of EB to the active centers were discussed. 相似文献
25.
H Iwamoto Y Kiyohara I Kato T Ohmura K Nakayama S Ohmori K Nomiyama T Yoshitake K Ueda M Fujishima 《Canadian Metallurgical Quarterly》1994,31(9):671-676
The authors studied mortality from major causes of death and risk factors in the elderly in a long-term prospective survey conducted in a Japanese suburban community, Hisayama. In the baseline survey in 1961, we scrutinized 1658 residents of the town aged 40 years or older accounting for 92% of the total population in this age range. Of those, 591 residents (245 men and 346 women) aged 60 years or older, who were free from major cardiovascular disease, were selected for the present study. They were followed-up for 26 years from 1961 to 1987. The average age was 67 years for men and 70 years for women, being significantly higher for women than for men. During the follow-up period, 529 subjects (89.5%) died, and 448 were autopsied (autopsy rate 84.7%). The all-cause mortality (per 1,000 person-years) after adjustment for age was 89.9 for men and 56.7 for women, the former being significantly higher than the latter (p < 0.01). The age-adjusted mortality from cerebrovascular disease was estimated to be 21.4 for men and 9.9 for women, i.e. 8.9 and 8.8 from heart disease, and 19.9 and 10.6 from neoplasm, and 18.1 and 12.2 from-pneumonia, respectively. There was significant sex difference in mortality from cerebrovascular disease, neoplasm and pneumonia (p < 0.01) but not from heart disease (p > 0.1). Multiple Cox's proportional hazards regression analysis showed systolic blood pressure and male sex to be significant risk factors for death by cerebrovascular disease. Systolic blood pressure was also a predictor for death by heart disease.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
26.
Based on homogeneous nucleation theory, the temperature dependence of the nucleation frequency for crystallization is calculated for a supercooled liquid. Here the solid-liquid interfacial energy of an alloy is estimated by means of an extension of Turnbull's assumption. Equations are suggested which correlate the energy with the ionization energy and the entropy of fusion for non-metallic bonded elements. 相似文献
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The thermophysical properties of three kinds of fruit juices (grape juice, orange juice, and pineapple juice) were measured at various temperatures (10–50 °C) and concentrations (10–50%). A new method for the simultaneous determination of thermophysical properties using a modified version of current probe theory method was proposed. The temperature changes of the probe upon insertion in the sample were fitted to an approximate solution of the heat conduction equation, and the values of two parameters in that solution were determined. Using the values of these parameters, the thermal conductivity and thermal diffusivity of each sample were determined. The specific heat of each sample was estimated from the definition of thermal diffusivity. These thermophysical properties were expressed as a function of concentration and temperature. 相似文献
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