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91.
Tomohito Hamazaki Masaharu Urakaze Masahiro Makuta Akio Ozawa Yasuji Soda Hiroshi Tatsumi Saburo Yano Akira Kumagai 《Lipids》1987,22(12):994-998
The ethyl ester of eicosapentaenoic acid (EPA) is the only pure EPA-containing lipid available in bulk for oral administration.
However, there is doubt as to whether EPA ethyl ester can efficiently increase the plasma levels of EPA in comparison with
the ability of other kinds of EPA-containing lipids to do so. Therefore, two other kinds of EPA-containing lipids were prepared
to study the efficiency of oral administration of those lipids for increasing the EPA content in plasma phospholipids and
cholesteryl esters. EPA-containing lipids which were investigated were [A], 1,2,3-trieicosapentaenoyl-glycerol, [B] 2-eicosapentaenoyl-phosphatidylcholine
and [C] ethyl ester of EPA. An adjusted amount of lipids [A], [B] and [C] was administered to rats through a gastric tube
for 4 days (the first experiment) or for 10 days (the second experiment), and the fatty acid composition of plasma phospholipids
and cholesteryl esters was determined. In the first experiment, there were no significant differences in the efficiency for
increasing EPA levels in either phospholipids or cholesteryl esters among the lipids. In the second experiment, the EPA levels
of both plasma phospholipids and cholesteryl esters of rats administered ethyl ester of EPA were significantly higher than
those of rats administered 2-eicosapentaenoyl-phosphatidylcholine. The EPA levels of the rats administered 1,2,3-trieicosapentaenoylglycerol
were between the levels of the two groups mentioned above, but the differences in the EPA levels were not significant. Although
an ethyl ester-type molecule is not a naturally occurring lipid, ethyl ester of EPA is equal to 1,2,3-trieicosapentaenoyl-glycerol
and appears to be superior to 2-eicosapentaenoyl-phosphatidylcholine as to the efficiency for increasing EPA levels in total
plasma phospholipids and plasma cholesteryl esters. 相似文献
92.
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94.
Taichi Sato Takato Nakamura Fusazi Ozawa 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1975,25(8):583-590
The thermal decomposition of nickel hydroxides prepared from aqueous nickel chloride solution on addition of alkali under various conditions has been examined by thermogravimetry, differential thermal analysis, X-ray diffraction study, visible and infrared spectrophotometry, magnetic susceptibility measurement and electron spin resonance spectroscopy. As a result, it is concluded that the thermal decomposition of nickel hydroxide proceeds in the following sequence: 相似文献
95.
Non-isothermal kinetics of the process of nucleation and its growth are derived by extending Avrami's equation. Kinetic analysis of the thermoanalytical data of the process is also described and applied to DSC curves of crystallization obtained by cooling poly(ethylene terephthalate) at constant rates. Crystallization is thought to proceed by nuclei being formed randomly and growing in three-dimensions. 相似文献
96.
Isotropic spherulites of carbon stable at 2000° C were synthesized by the pressure pyrolysis of divinylbenzene polymer sealed in a capsule. The morphology of the synthesized carbon was pressure and temperature dependent being influenced by the state of polymerization of the starting polymer. Using a polymer prepared at atmospheric pressure and 150° C without catalyst, isolated spherulitic carbon was formed at 700° C and pressures of 1000 to 1250 kg cm–2. These spherulitic carbons were optically isotropic, hard and non-graphitizable after heat treatment at 2000° C. Such carbons originate in the co-existence of higher and lower molecular weight products of pressure pyrolysis and the survival cross-linkages in the original polymer. 相似文献
97.
98.
A surface bidirectional reflectance distribution function (BRDF) depends on both the optical properties of the material and the microstructure of the surface and appears as combination of these factors. We propose a method for modeling the BRDF based on a separate optical-property (refractive-index) estimation by polarization measurement. Because the BRDF and the refractive index for precisely the same place can be determined, errors cased by individual difference or spatial dependence can be eliminated. Our BRDF model treats the surface as an aggregation of microfacets, and the diffractive effect is negligible because of randomness. An example model of a painted aluminum plate is presented. 相似文献
99.
100.