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991.
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John R. Fischer Robert J. De Angelis O.J. Hahn Peter P. Gillis 《Fuel Processing Technology》1977,1(1):65-87
The steel inner liner of a coal gasifier was examined. This liner had been directly exposed to a coal gasification reaction for 20 years. The microstructure was observed and the chemical composition analyzed as functions of position in the vessel. Evidence of corrosion, embrittlement, and carburization was sought. Although pronounced microstructural variations were observed in this steel liner, the chemical composition was found to be quite uniform. 相似文献
995.
996.
The effects of single and repeated pargyline administration on morphine antinociception in both naive and morphine-tolerant mice and on naloxone-precipitated withdrawal in morphine tolerant-dependent animals were investigated. Adult, male Swiss-Webster mice were rendered tolerant to and dependent on morphine by the s.c. pellet implantion technique. Morphine analgesia, as assessed by the tail-flick antinociceptive test, was potentiated in tolerant animals by acute adminstration of pargyline but antagonized by repeated pargyline administration; pargyline produced similar effects in non-tolerant mice and to the same relative degree. Repeated pargyline treatment during morphine pellet implantation enhanced the withdrawal jumping response precipitated by naloxone in dependent mice. Pargyline also, after a single injection, exacerbated jumping in mice undergoing abrupt withdrawal. Neither acute nor chronic pargyline administration altered the brain distribution of injected morphine in non-tolerant mice. It was concluded that pargyline may modify acute morphine actions and withdrawal without materially altering the process(es) involved in the development of tolerance and physical dependence. 相似文献
997.
H Vetter W Vetter R Beckerhoff K Gl?nzer J Furrer C Hahn R Kolloch F Krück K Kutz W Siegenthaler F Witassek 《Canadian Metallurgical Quarterly》1977,107(48):1755-1759
Supine plasma aldosterone and plasma renin activity were determined in patients with cirrhosis of the liver and ascites (n = 10). Most of the patients initially showed an increase in plasma aldosterone and plasma renin activity. However, values within the normal range were observed (plasma aldosterone, n = 3; plasma renin activity, n = 4). In the ascitic fluid renin activity could not be detected, whereas aldosterone concentrations correlated significantly with the respective plasma levels (r = 0.8, p less than 0.01). During therapy with spironolactone alone (n =2) or in combination with furosemide (n = 4), diuresis and natriuresis showed no correlation with changes in plasma aldosterone and/or plasma renin activity. Our results suggest that other factors than renin and aldosterone secretion may be important in the formation of ascites in patients with cirrhosis of the liver. In addition, the inverse correlation between mean arterial blood pressure and plasma renin activity (r = -0.65, p less than 0.05) found in our patients supports the assumption that the increase in renin secretion is probably induced by changes in (renal) hemodynamics. 相似文献
998.
DeRosa Joseph F. Beard Richard B. Hahn Allan W. 《IEEE transactions on bio-medical engineering》1970,(4):324-330
The power output of flexible zinc and aluminum anodes in a plastic binder compared favorably with that of pure metals used in previous implantable hybrid cells. Cathodes of platinum and palladium black in a polyvinyl chloride binder compared well with cathodes of platinum black in teflon. In-vivo and in-vitro measurements on palladium black cathodes with a polyvinyl chloride binder indicate that they perform better than the platinum black cathodes using plastic binders. A spreading resistance measurement correlated with the catalytic activity of the cathode. Modified galvanostatic and spreading resistance measurements were used in in-vitro studies to evaluate the fabricated cathodes. 相似文献
999.
CA Vaamonde UF Michael JR Oster MJ Sebastianelli LS Vaamonde EL Klingler S Papper 《Canadian Metallurgical Quarterly》1976,17(5):382-395
The renal concentrating ability was studied in ten patients with hypothyroidism and in 15 euthyroid controls. Solute-free water reabsorption was reduced in the patients with myxedema (4.2 +/- 0.3 ml/min: controls 5.8 +/- 0.6 ml/min; p less than 0.01). This defect was apparent at high rates of solute excretion, and was associated with enhanced excretion of sodium (p less than 0.01) despite a decreased filtered load (p less than 0.005). The myxedema patients had a modest reduction in maximal urine osmolality (p less than 0.04), which was entirely attributable to the lower values observed in younger patients. The results may be explained best by decreased sodium chloride reabsorption in the ascending limb of Henle's loop and/or diminished permeability of the distal nephron in myxedema. 相似文献
1000.