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81.
Literature data are reviewed concerning morphological and morphogenetic features of stomach ulcer, vascular alterations in both the ulcer zone and other regions of the stomach. Stages in ulcer formation, its healing and prognostic criteria are described. Further study of ulcerogenesis regarding histotopographic features of different regions of gastro-intestinal tract is recommended. 相似文献
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A considerable decrease in pressor responses to polyglykine at an elevated arterial tone and constant increase of cardiac output occurred in anesthetised rats. Vascular and cardiac mechanisms of the interrelationship are discussed. 相似文献
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We compared the antimicrobial activities of two rigid gas permeable (RGP) lens care systems, a one-step wetting and soaking system (0.005% chlorhexidine gluconate, 0.02% EDTA) and a conditioning solution (0.006% chlorhexidine gluconate, 0.05% EDTA). The formulations were individually inoculated with approximately 10(6) CFU/mL of a pathogenic organism. Both the one-step wetting and soaking system and the conditioning solution demonstrated good antimicrobial efficacy against Pseudomonas aeruginosa, Staphylococcus epidermidis, Serratia marcescens, and Aspergillus fumigatus. However, the one-step wetting and soaking system provides better disinfection against Candida albicans (1.2 log reduction in 4 hours) than the conditioning solution (0.39 log reduction in 4 hours). The one-step system also reduced S. marcescens by 5 logs in 1 hour, whereas the conditioning solution reduced S. marcescens by about 2 logs only in the same time interval. Although both RGP lens care systems use the same active preservative (chlorhexidine digluconate), the variation in disinfecting activities may be attributed to differences in formulation and buffer systems. 相似文献
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The major factor limiting resolution of metal-shadowed surfaces for electron and scanning tunnelling microscopy is the granularity of the metal film. This granularity had been believed to result from a recrystallization of the evaporated film, and hence could be limited by use of higher melting point materials for replication, or inhibited by adding carbon or other impurities to the film. However, evaporated and sputtered films of amorphous metal alloys that do not crystallize also show a granularity that decreases with increasing alloy melting point. A simple thermodynamic analysis shows that the granularity results from a dewetting of the typically low surface energy sample by the high surface energy metal film, similar to the beading up of drops of spilled mercury. The metal granularity and the resulting resolution of the metal-coated surface is proportional to the mobility of the metal on the surface after evaporation, which is related to the difference in temperature between the melting point of the metal and the sample surface temperature. 相似文献
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In order to validate a rodent biochemical model of delayed neurotoxicity of organophosphates (OP) inhibition of rat and hen brain neurotoxic esterase (NTE) by some dichlorovinyl phosphates and phosphonates was studied in vitro and in vivo. It was shown that compounds investigated exhibited the similar inhibitory potency to NTE from both species in vitro, in addition rat and hen NTE showed the same sensitivity to variation of the structure of OP inhibitors. A good correlation was found between pI50 estimated with enzymes from rat and hen trains: r2 = 0.951, n = 18, p < or = 0.05. NTE activities were also measured in rat and hen brains after acute administration of various dosages of potent axonopathic compound dipropyldichlorovinyl phosphate. The results obtained indicate that difference in species susceptibility to neurotoxic action of OP, in particular the absence of ataxia in rats, is not caused by difference in target enzyme sensitivity to axonopathic organophosphates. 相似文献