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71.
IM Savitskaia 《Canadian Metallurgical Quarterly》1997,(5-6):54-56
Investigation of manufacturing of home-produced dissolving suture material was conducted. Influence of the material on tissues in the region of threads location and on the organism as a whole was studied up. The material resolved actively, did not cause pathological changes in surrounding tissues and in general pathological processes in the organism of animals. During 180 days the majority of the suture material quantity have resolved. 相似文献
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The dissolution of metals from various metal-mine tailings has been studied through a series of submerged tailings batch tests at U.S. Bureau of Mines laboratories. Tailings selected for this study included both reactive (as determined by column leaching studies) and benign tailings. Metal mobilization in aerated (97 pct saturated with oxygen) samples appeared to be consistently greater than metal dissolution from stagnant (79 pct or 70 pct saturated with oxygen) waters. In the early weeks of the study, sulfate concentrations increased with solid-liquid contact time, while calcium dissolution remained nearly constant. Metal concentrations varied in relation to solid-liquid contact time and aeration. Leachate pH appeared to be nearly independent of solid-liquid contact time for basic tailings. Reactive tailings having both a submerged and a surface component demonstrated increased metal mobility. 相似文献
74.
The flame retardation mechanisms for cellulose treated with systems based on aromatic phosphates and phosphoramides have been investigated through pyrolysis studies on cellulose and related model compounds. Pyrolysis of cellulose treated with phosphates or phosphoramides proceeds through formation of cellulose phosphate or phosphoramide esters, followed by subsequent ester pyrolysis to yield a dehydrated cellulose char. Formation of phosphoramides during pyrolysis of flame retardants containing phosphorus and nitrogen constitutes a possible basis for reported phosphorus-nitrogen synergistic effects observed in commercial flame retardants. Efficiency of ester formation is higher, and subsequent pyrolysis is lower for phosphoramides than for phosphate esters. The build-up of a thermally stable crosslinked matrix in the residue occurs on pyrolysis of cellulose treated with phosphoramides. Such crosslinking seems to be effective in enhancing flame retardation. 相似文献
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Ruiz Mark A.; Drake Evan B.; Glass Aviva; Marcotte David; van Gorp Wilfred G. 《Canadian Metallurgical Quarterly》2002,33(3):294
Although the Internet may be beneficial to clinical practice, its potential for misuse cannot be overlooked. The current probe identified Internet Web sites that contained information that violated the test security of psychological assessment instruments. Five individuals, using multiple search engines, conducted Internet searches to evaluate samples of Web sites. Sites were classified into 1 of 3 levels according to the degree of threat they posed to test security. A small number (2-5%) appeared to be a direct threat to test security. The findings are discussed and recommendations for promoting more ethical use of the Internet are made. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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AH Rezvani DH Overstreet Y Yang IM Maisonneuve UK Bandarage ME Kuehne SD Glick 《Canadian Metallurgical Quarterly》1997,58(2):615-619
We previously reported that single administration of ibogaine, an indol alkaloid with antiaddictive properties, dose dependently reduced alcohol intake in three strains of alcohol-preferring rats. The present study examined the effect of different doses of a newly developed nontoxic ibogaine analogue, 18-methoxycoronaridine (18-MC), on alcohol intake. Selectively bred alcohol-preferring rats received a single intraperitoneal injection of vehicle or 5, 20 and 40 mg/kg of 18-MC at 9:30 AM, and their consumption of alcohol, water and food was measured for 24 h. Our results demonstrate that a single injection of 18-MC significantly and dose dependently attenuated alcohol consumption and preference and commensurately increased water intake. Only the highest dose of 18-MC significantly decreased food intake. Although the true mechanism of action of 18-MC in suppressing alcohol intake is not yet fully understood, it may, like ibogaine, exert its attenuating effects on alcohol consumption by modulating neurotransmitters believed to be involved in the regulation of alcohol intake. 相似文献
80.
Sixteen phages active against bacteria of the genus Serratia have been divided into 4 groups on the basis of the study of their biological properties. As a result, 5 typing phages have been selected, which permitted the typing of 77.3% of S. marcescens cultures under study, divided into 13 phage types. 相似文献