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461.
Acidocillin levels were determined in the middle ear exudates and serum of patients with acute exudative otitis media after oral administration of the drug. Acidocillin rapidly diffused exudate into the ear and its level in the exudate in 1 hour was 0-1.7 gamma/ml. At the same time the serum levels ranges within 4 to 25 gamma/ml. acidocillin remained longer in the ear exudate than in the serum. In 12 hours 0.2 to 1.3 gamma/ml of acidocillin was still found in the exudates, while there was no antibiotic in the serum. 相似文献
462.
Macrozoobenthos of Lake Peipsi-Pihkva: long-term biomass changes 总被引:1,自引:1,他引:0
Macrozoobenthos of the large (3,558 km2) Lake Peipsi-Pihkva was monitored at 22–24 sampling spots yearly in June 1964–1994 as well as 50 shallow-water profiles in mid-summer 1970, 1980, and 1990. No qualitative changes were observed in the bottom fauna, except for the introduction of a Baikalian gammarid species, Gmelinoides fasciatus. The average total biomass in June (without big molluscs) revealed considerable annual fluctuations, with an insignificant general tendency of increase. The increase was significant in the biomass of several Mollusca (including the highly abundant big clam Dreissena polymorpha), Asellus, Gammaridae, and Hirudinea but not in the most abundant animal groups Chironomidae and Oligochaeta. The low biomass of Ephemeroptera and Hydrachnellae decreased significantly. The mid-summer samples taken from the shallow-water zone in three different years revealed the highest biomass in 1980 and the lowest in 1990 (the latter being probably related to the high water level). A gradual decrease in the biomass of the Ephemeroptera and Hydrachnellae as well as the Oligochaeta, Pisidiidae and Bithynia tentaculata occurred in the shallow-water zone, while the Gammaridae increased on the account of the introduced species. No coincidence was found with the neighbouring Lake Võrtsjärv when comparing the annual fluctuations of biomass. A general tendency to a slow increase in total biomass and a decrease in the biomass of the most vulnerable groups Ephemeroptera and Hydrachnellae, probably due to progressing eutrophication, were common for both lakes. 相似文献