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81.
Despite the excellent in vitro potency of a series of benzamide glycoprotein IIb/IIIa antagonists, which have been reported previously, poor in vivo potency in the inhibition of platelet aggregation was observed when the most potent inhibitor XU057 was dosed intravenously to dogs. In this communication, we report that replacement of the benzamide in XU057 with an isoxazolecarboxamide resulted in significant improvement in in vivo potency. More importantly, the analogue XU065 showed an excellent oral antiplatelet effect in dogs.  相似文献   
82.
Graves' disease (GD), myasthenia gravis (MG), and polymyositis (PM) are organ-specific autoimmune diseases. The association between GD and MG is well known, and an association between MG and PM has been reported. However, only one patient with all three diseases has been reported. We describe a patient with GD and PM developing 6 and 29 years, respectively after the onset of MG. This case suggests that the expression of autoimmunity occurred over a prolonged period of time and these organ-specific autoimmune diseases may be induced by a similar mechanism.  相似文献   
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Solidification of phase change material around a vertical cylindrical surface was studied to investigate the performance of ice storage system and stored thermal energy. Air bubbles were generated in the phase change material at various air flow rate as a gas holdup to enhance the heat transfer rate and accelerate the ice layer growth at the solid–liquid interface. The test tube surface was cooled by ethylene glycol–water solution at a flow rate of 40% concentration by weight. The ice layer growth and solidification front velocity at solid–liquid interface were estimated from the temperature–time recorded data of a set of thermocouples fixed in a radial position perpendicular to cooled surface. The ice layer growth at the first instants of solidification process is much higher. Thereafter it decreased gradually according to the increasing of thermal resistance of ice layer. The increasing of ethylene glycol–water solution mass flow rate seems to accelerate the solidification process with small rate. The effect of air bubbles agitation was found to increase the ice layer growth rate and solidification front velocity by about of 20–45%. As a consequence the stored thermal energy was increased by about 55–115% with increasing air bubbles flow according to the attribute of generates turbulence at the solid–liquid interface. The measured data showed that with stirring the bulk water in energy storage tank, the storage time can be reduced by 10–35% of that without stirring.  相似文献   
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Summary A new nematic monomer — p-( -acryloyloxycaproyloxy)p-methoxyphenylbenzoate — was synthesized. A homepolymer of this monomer and its copolymer with cholesteryl--acryloyloxycapronate were prepared by radical polymerization. The homopolymer forms the mesophase of nematic type. The copolymer forms the cholesteric mesophase that shows selective light reflection. The maximum wavelength of the reflected light is equal to 495–500 nm and is not changed on temperature.Part 7. R. V. Talroze, V. V. Sinitzyn, V. P. Shibaev, N. A. Plate Polymer Bull. 6, 309 (1982)  相似文献   
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In this study, 4‐amino‐9‐methoxypropylnaphthalimide fluorescent dye (dye 1 ) was reacted with poly(amidoamine) dendrimer G = ?0.5 to prepare a naphthalimide–dendrimer hybrid dye (dye 2 ). The chemical structures of the synthesised dyes were confirmed by elemental analysis, Fourier transform infrared spectroscopy, 1H nuclear magnetic resonance spectroscopy, and ultraviolet‐visible spectroscopy. The solvatochromism of the dyes was evaluated in various solvents with respect to visible absorption properties, and positive solvatochromism was observed by solvent polarity change from chloroform to ethanol. The dyeing ability of the synthesised dyes was investigated by their application onto nylon fabric, and nylon substrates dyed with dye 2 exhibited marked enhancement both in terms of colour strength and general fastness properties. The results of this study clearly demonstrated the high potential and performance of dye 2 as a novel promising fluorescent dye as compared with dye 1 . Overall, it was inferred that the modification of the naphthalimide fluorescent dye with poly(amidoamine) denderimer could markedly improve the dyeing and fastness properties of the naphthalimide fluorescent dye on nylon fabrics.  相似文献   
90.
A new symmetrical diamine monomer containing dioxypyrimidine and two diaryl imidazole bulky pendent group was synthesized by the nucleophilic substitution reaction of 4,6 dihydroxy pyrimidine with the synthesized 2-(2-chloro-5-nitrophenyl)-4,5-diphenyl-1H-imidazole (I). A series of novel fluorescent imidazole-containing polyamides (PAs) with inherent viscosities of 0.52–0.78 dL/g was prepared by direct polycondensation of the diamine with various dicarboxylic acids. These PAs were readily soluble in many organic solvents and could be solution-cast into tough and flexible films. The PAs exhibited glass transition temperatures (Tg)s between 202 and 260 °C, and 10% weight loss temperatures in the range of 345–470 °C in air. In addition, three novel polyimides (PIs) with inherent viscosities of 0.38–0.56 dL/g were prepared by addition reaction of the diamine with commercially available tetracarboxylic dianhydrides and subsequent chemical imidization. The PIs exhibited good solubility in polar solvents such as NMP. These polymers exhibited Tgs in the range of 237–285 °C and their 10% weight-loss temperatures varied from 440 to 520 °C.  相似文献   
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