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Protoscoleces from human, camel, cattle, sheep, goat (all from Kenya) and buffalo (from India) hydatid cysts were cultured under identical conditions in vitro using the diphasic culture system of Smyth (1979b). Organisms from all sources grew and segmented in culture. Genital anlagen developed in all cultured worms but further genital differentiation occurred only in cultures of cattle (testes) and camel (testes and genital pore) material. The possible significance of these results is discussed in relation to the general epidemiology of hydatid disease and the potential infectivity of the different strains to man. 相似文献
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Macpherson JW Penner P 《Canadian journal of comparative medicine and veterinary science》1967,31(3):62-64
Two methods of semen collection were attempted on ten untrained dogs of several breeds. Manual manipulation as described proved most reliable for untrained dogs. Electro-ejaculation was attempted unsucessfully with twelve additional dogs.Two methods of insemination were compared. Equipment found most satisfactory is described and a modification suggested. 相似文献
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David G. Bishop Janette R. Kenrick James H. Bayston Athol S. Macpherson Stanley R. Johns 《生物化学与生物物理学报:生物膜》1980,602(2):248-259
The properties of seven monogalactosyldiacylglycerols and six digalactosyldiacylglycerols, isolated from photosynthetic membranes and possessing different levels of fatty acid unsaturation, have been studied by the monolayer technique and compared with those of the fully saturated compounds. In addition, the monolayer properties of sulphoquinovosyldiacylglycerols and phosphatidylglycerols from higher plant chloroplasts, and several hexadecenoic acids have been measured.Monogalactosyldiacylglycerols containing saturated fatty acids form a condensed monolayer similar to that of saturated phosphatidylcholines. The naturally occurring monogalactosyldiacylglycerols, of which the double bond index ranged from 0.6 to 3.9, possessed comparable force-area curves suggesting that headgroup interactions play a more important role in packing behaviour than in phosphatidylcholines. Although digalactosyldiacylglycerols containing fully saturated fatty acids form a more expanded monolayer than the corresponding monogalactosyldiacylglycerols, the degree of expansion of the monolayer due to the presence of unsaturated fatty acids in the naturally occurring digalactosyldiacylglycerols is much less than in monogalactosyldiacylglycerols. Monogalactosyldiacylglycerols and digalactosyldiacylglycerols from a single species have very similar monolayer properties, and the presence of sulphoquinovosyldiacylglycerols and phosphatidylglycerols in the proportions in which they occur in higher plant chloroplasts does not have any condensing effect on a monolayer of galactolipids 相似文献
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PIERRE‐OLIVIER ANTOINE KEVIN F. DOWNING JEAN‐YVES CROCHET FRANCIS DURANTHON LAWRENCE J. FLYNN LAURENT MARIVAUX GRÉGOIRE MÉTAIS ABDUL RAHIM RAJPAR GHAZALA ROOHI 《Zoological Journal of the Linnean Society》2010,160(1):139-194
Rhinocerotids are particularly abundant and diversified in Neogene deposits of the Indian subcontinent, but their systematics is far from being well defined. Based on the revision of old collections and new findings from the Early Miocene of the Bugti Hills and Zinda Pir, Pakistan, ‘Aceratherium blanfordi Lydekker, 1884’ is a chimera, consisting of two dentally convergent but postcranially distinct rhinocerotid taxa: Pleuroceros blanfordi and Mesaceratherium welcommi sp. nov. Postcranial features appear to be much more diagnostic than craniodental morphology in this case. A phylogenetic analysis based on 282 morphological characters scored for 28 taxa (four outgroups and ingroup including both taxa of interest and a ‘branching group’) strengthens this statement and supports Pleuroceros and Mesaceratherium as monophyletic genera within Rhinocerotinae. Both genera are recognized for the first time outside Europe. In the Bugti Hills, P. blanfordi and M. welcommi are part of an exceptionally diversified rhinocerotid fauna, with up to nine species associated in the same locality (Kumbi 4f). This rhinocerotid assemblage confirms the earliest Miocene age (Agenian/Aquitanian) of the upper member of the Chitarwata Formation as a whole. Coeval homotaxic rhinocerotid faunas from Europe (France, Czech Republic) and East Africa (Uganda, Kenya) support broad and sustainable rhinocerotid interchanges amongst South Asia, Europe, and Africa under compatible environmental conditions throughout earliest Miocene times. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 160 , 139–194. 相似文献