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991.
992.
Seven sexually mature boars were studied in two-hour intervals for 8 to 32 hours, as to the variation of testosterone levels in the blood plasma. Blood samples were obtained by means of a cannula inserted in the v. cava cranialis. The hormone level under study showed marked fluctuation. The coefficient of variation of testosterone concentration ranged from 12.7% to 35.2% in the individual animals and for the whole part of the study it was 33.0%. It appeared impossible to derive seriously any regular periodicity of testosterone concentration in boar blood in the 24-hour period from the analysis of the variation of the levels of the hormone in individual animals during the period under study. Further, the study revealed a marked fluctuation of testosterone levels in the blood plasma of twelve sexually mature boars in the course of several days' study. The coefficient of variation of testosterone concentration in individual animals ranged from 18.1% to 106.5%, reaching 77.0% for the whole part of study. The analysis of variance showed statistically significant differences of hormonal levels in individual boars in which the fluctuation of testosterone was studied in the 8- to 32-hour period as well as in several days' period. This proved the role of the animals' individuality in determining the concentration of testosterone in their blood. The discussion concerns the importance of these findings for the evaluation of the role of basal testosterone levels in the blood in classifying the incretion function of the gonads and in the diagnosis of incretion hypogonadism of boars. 相似文献
993.
Tests of the efficiency of antigens prepared from different developmental stages of Ascaris suum in indirect haemagglutination test in the course of proving the migration phase of experimental ascariasis in pigs show that the antigens prepared by ultrasound from the invasive larval stage of A. suum in comparison with antigens of sexually mature stages have higher serological activity. By using this antigen it is possible to prove specific antibodies in experimentally invaded pigs from 6 to 120 days after invasion as opposed to the other tested antigens (the detectability of antibodies from the 7th-8th day to the 64th day after invasion). 相似文献
994.
Urea concentration in plasma, muscle, and liver fluids of Wistar rats at the age of 3, 6, and 12 weeks was determined. In rats at the age of 3 weeks urea was cumulated in liver and muscle tissue fluids, in older rats (6 and 12 weeks) in plasma fluid. According to the stated urea distribution in individual age categories, a higher urea transport from tissues to blood is considered to be in rats at the age of 6 and 12 weeks. The urea transport proved to be one of the mechanisms of facilitating better utilization of endogenous urea nitrogen in bio-synthetic processes of the nitrogen metabolism in ruminants as well as in monogastric animals. 相似文献
995.
The breast and shoulder-blade muscles of a roe (Caprelous capreolus L.), shot in a hunting district in western Bohemia, were found to contain cysticerci with morphological characters and size corresponding to those of Cysticercus tarandi, which is a developmental stage of the tapeworm Taenia krabbei Moniez, 1879. The surface as well as deeper layers of muscle contained one to two cysticerci per 100 cm2 of area. The authors describe the larvocysts and histological changes in the site where the micro-organisms were found. The cysticerci are discussed as to the species to which they belong. 相似文献
996.
997.
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999.
Procedures are described for the analysis of crops for residues of tetrachlorvinphos (Gardona, trans-isomer of dimethyl 1-(2′,4′,5′-trichlorophenyl)-2-chloroyinyl phosphate) insecticide together with methods for the analysis for residues of its isomer and its conjugated and non-conjugated breakdown products. Suitable procedures for the extraction are described together with procedures for the cleanup of the extracts by partition or column chromatography and final analysis down to 0·01 ppm or less by gas-liquid chromatography with electron capture detection. 相似文献
1000.