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31.
Two patients with polymyositis (PM) or dermatomyositis (DM) complicated with massive pleural effusion are reported here. Both patients presented a high-grade fever, pleural effusion prominent on the right, and good response to steroid therapy. In a 50-year-old woman with PM, combined process of pleural inflammation, cardiomyopathy and coexisting hypothyroidism were considered to be responsible for the accumulation of the massive pleural effusion. However, in a 34-year-old man with DM, pleural inflammation associated with interstitial pneumonia or pleural microvasculopathy in DM was considered to be responsible for the accumulation of the massive pleural effusion.  相似文献   
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We measured the activity of mitogen-activated protein (MAP) kinases, enzymes believed to be involved in the pathway for cell proliferation, in rat aortic strips with or without endothelium, and examined effects of angiotensin receptor antagonists, endothelin receptor antagonists and nitric oxide (NO)-related agents. Endothelium removal produced an activation of MAP kinase activity in the strips, whereas the enzyme activity was not affected in the adventitia. The MAP kinase activation was inhibited by either the angiotensin AT1 receptor antagonist losartan or the endothelin ETA receptor antagonist BQ 123. The combination of both antagonists caused an additive inhibition. The angiotensin AT2 receptor antagonist PD 123,319 and the endothelin ETB receptor antagonist BQ 788 did not affect the MAP kinase activation. The NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) caused an activation of MAP kinase in the endothelium-intact aorta and the MAP kinase activation was inhibited by losartan or BQ123. The NO releaser nitroprusside inhibited the MAP kinase activation induced by endothelium removal or angiotensin II. These results suggest that even in isolated arteries, NO of endothelial origin tonically exert MAP kinase-inhibiting effects and endogenous angiotensin II and endothelins in the media are tonically released to cause MAP kinase-stimulating effects in medial smooth muscle.  相似文献   
34.
Based on the Cramer-Rao inequality, the MILB is calculated for the problem of estimating the frequency slope of the attenuation coefficient of tissue from random reflections of ultrasonic waves. Under typical signal conditions, this bound for a 1-cm x 1-cm region was found to be about 0.08 db/(MHz-cm), rather close to the clinical requirement of 0.1 dB/(MHz-cm). Comparison to existing methods (including an autoregressive deconvolution method) shows room for further improvement.  相似文献   
35.
Two special cases of the bilateral 2-D polynomial matrix equationDU +VN=C whenC=I andC=I with being a -stable 2-D polynomial, which are related respectively to deadbeat and asymptotic control problems of 2-D systems, are first considered. By generalizing the concepts of factor coprimeness, zero coprimeness and zero skew primeness in the 2-D polynomial ring to the ring of causal -stable 2-D rational functions, a constructive solution of these two problems mentioned is proposed. Based on these results, we derive a solvability condition for the bilateral equiation whereC is a general 2-D polynomial matrix. The general solutions are investigated as well.  相似文献   
36.
Needle-like or wool-like Al2O3 whiskers can be grown on a substrate by the hydrolysis of aluminium fluoride vapour. Effects of the growth conditions on the morphology of the crystals and growth processes of the whisker were investigated, and the optimum growth condition of whiskers was examined. Adequate vapour pressure conditions of the reactant gases for the growth of the wool-like whisker were found to be . Aluminium oxyfluoride was assumed to be the most probable intermediate species for the growth of Al2O3 whiskers. A variety of crystal morphologies are also shown and described with respect to the experimental conditions.  相似文献   
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A theoretical equation for the dependence of the apparent molecular weight measured by light scattering on the solvent used has been derived with regard to the composition heterogeneity. Terpolymers corresponding to a partial azeotrope were synthesized from styrene, acrylonitrile, and methyl methacrylate with mole fractions of 0.55, 0.16, and 0.29, respectively. The molecular weight measured by light scattering was found to be independent of the solvent used. Therefore the terpolymer was concluded to be apparently homogeneous in composition. The relationship between the molecular weight M of the terpolymer and the volume fraction of the nonsolvent γ in the solvent mixture at the precipitation point in a butanone-methanol-terpolymer system was experimentally proved to follow the equation where γ0 and b′ are constants. Between the molecular weight and the limiting viscosity number [η] of the terpolymer the following relationships are valid at 35°C: and   相似文献   
39.
M. Kajiwara  M. Makihara  Hajime Saito 《Polymer》1977,18(10):1045-1046
The Spiro compound N3P3(OCH2CF3)4(NH)2Si(CH3)2 formed by reaction of 1,1-diamino-3,3,5,5-tetrakis(2,2,2-trifluoroethoxy)cyclotriphosphazene N3P3(OCH2CF3)4(NH2)2 and dimethyldichlorosilane Cl2Si(CH3)2 is a yellow or orange coloured oil soluble in organic solvents, vapourized at 160°C without decomposition, and not hydrolysed appreciably in boiling water. Linear compounds are formed by reaction of N3P3(OCH2CF3)4(NH2)2 with diphenyldichlorosilane or phenyltrichlorosilane owing to hindrance of the phenyl radical. These compounds are amorphous or tacky solids, soluble in organic solvents and stable to water.  相似文献   
40.
Abstract— A 9‐in. full‐color polymer‐stabilized OCB TFT‐LCD with stable bend alignment in the absence of an electric field was developed. The condition of the polymer stabilization, the characteristics of UV‐curable monomers, and their influence on the configurations of the polymer network in the cell were studied. Possible models of the configuration were proposed and their relationship to the electro‐optical properties was analyzed using a novel simulation method considering the distribution of anchoring effects from both alignment surfaces and the polymer network. It was suggested that a good performance such as high contrast ratio and fast response could be expected in the polymer network originating from newly developed monomers composed of multifunctional LC acrylates due to a relatively weak‐anchoring effect and presumably its localization near the alignment surfaces. By using the newly developed monomers under the optimized polymer‐stabilizing process, a high contrast ratio of 250:1 and fast response nearly equal to that of a conventional OCB cell were achieved.  相似文献   
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