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111.
The effect of several factors in relation to the quantities of dieldrin accumulated in different organs of broilers was studied. Feedstuff was contaminated at doses of 60, 90, 120, 200 and 240 ppm. With the doses used, the results show an accumulation summit over which the amounts accumulated are not affected by greater quantities of dieldrin ingested. The accumulation of dieldrin in the female is greater than in the male and the weight of the animal does not significantly affect the response.  相似文献   
112.
The antigenic patterns recognised by Western blotting in seed proteins of species of Opuntioideae (Cactaceae) were analysed in an attempt to evaluate their usefulness in systematics. Total protein profiles were also analysed by SDS–PAGE. The resulting similarity and distance matrices were further used to carry out Cluster Analysis (UPGMA) and Principal Coordinates Analysis. Populations of Opuntia cardiosperma were found to exhibit a prominent morphological uniformity, a unique electrophoretic pattern and a uniform antigenic pattern. The latter was obtained using anti-O. cardiosperma as antiserum. Results from the qualitative and quantitative interspecific analyses of antigenic profiles helped to characterise all the species studied. Tephrocactus articulatus and Cylindropuntia imbricata evidenced lower affinity with O. cardiosperma than the species of Opuntia s.s. Our results demonstrate that in Cactaceae, Western blotting analysis broadens the usefulness range of immunological techniques at the specific level and complements the information collected from electrophoretic profiles.  相似文献   
113.
Seeds of Cucurbita maxima, C. moschata and their interspecific hybrids were used to evaluate the intrapopulational and interpopulational variation of their protein composition. Three immunoprecipitating systems common to all the studied samples were detected by the Ouchterlony technique. Fourteen protein bands were identified by polyacrylamide gel electrophoresis (PAGE) whereas 23 bands were identified by sodiumdodecylsulfate (SDS)-PAGE. Using Western blotting (WB) also 23 bands were detected. The Jaccard's index of similarity calculated from SDS-PAGE and WB varied between 91 and 100 % for all the compared pairs of samples. These results demonstrate a high uniformity in the protein composition of all the samples and do not allow for their clear characterization.  相似文献   
114.
Apteryx is a genus of flightless birds endemic to New Zealand known to lay very large eggs in proportion to body weight. The eggshell of Apteryx is unusually thin and less porous than allometrically expected possibly as a compensation for a very long incubation period. Past studies have been carried out on Apteryx australis, a species which once comprised all kiwi with brown plumage, now separated into three distinct species. These species use different habitats and live at different latitudes and altitudes, therefore generating a need to revise our knowledge of the attributes of their eggshells. In this study, we measured the physical characteristics and water conductance on eggshell fragments of these three species and Great‐spotted Kiwi and relate them to the environmental conditions of their respective environments; we also measured the water vapor conductance of Brown Kiwi eggs of late stages of incubation. We found that several trade‐offs exist between incubation behavior, environmental conditions, and eggshell structure. We found differences between species in eggshell water vapor conductance seemingly related to altitude; Brown Kiwi and Rowi generally inhabiting lower altitudes had the highest conductance and Tokoeka, generally living in montane environments, the lowest. This is achieved by an increased eggshell thickness rather than a pore area reduction. Finally, the water vapor conductance late in incubation was 58% higher than infertile unincubated eggs, suggesting a drastic increase in conductance throughout the long incubation period. Using the values previously reported, we calculated the embryonic eggshell thinning to be 32.5% at the equatorial region of the eggshell. We describe several new features, such as triangular mineral particles in the cuticle, reported for the extinct Trigonoolithus amoei, and confirmed the existence of plugged pores. We suggest that these structures provide microbial protection needed by a burrow nesting species with a long incubation period.  相似文献   
115.
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