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A curious approximate construction for VCEmax   总被引:1,自引:0,他引:1  
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M A Peirce 《Parasitology》1980,80(3):551-554
A staining technique was developed for locating the sporozoites of Eimeria spp. in both mammalian and avian hosts. Bouin-fixed tissues embedded in Paraffin wax and cut at a thickness of 3 micrometers were stained by a controlled sequence of Ehrlich's haematoxylin, acid fuchsin and aniline blue-orange G-acetic acid which took only 30 min to perform. The refractible globule of the sporozoite stained a brilliant crimson whilst the tissue had an overall blue colour, thus enabling rapid scanning of material under low-power magnification. The granules of eosinophils and heterophils also stained a brilliant crimson and their significance in immunological responses indicates a wider application for this technique.  相似文献   
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Background  

Development, differentiation and physiology of metazoans all depend on cell to cell communication and subsequent intracellular signal transduction. Often, these processes are orchestrated via sites of specialized cell-cell contact and involve receptors, adhesion molecules and scaffolding proteins. Several of these scaffolding proteins important for synaptic and cellular junctions belong to the large family of membrane-associated guanylate kinases (MAGUK). In order to elucidate the origin and the evolutionary history of the MAGUKs we investigated full-length cDNA, EST and genomic sequences of species in major phyla.  相似文献   
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Agent-based modeling (ABM), also termed ‘Individual-basedmodeling (IBM)’, is a computational approach that simulatesthe interactions of autonomous entities (agents, or individualcells) with each other and their local environment to predicthigher level emergent patterns. A literature-derived rule setgoverns the actions of each individual agent. While this techniquehas been widely used in the ecological and social sciences,it has only recently been applied in biomedical research. Thepurpose of this review is to provide an introduction to ABMas it has been used to study complex multi-cell biological phenomena,underscore the importance of coupling models with experimentalwork, and outline future challenges for the ABM field and itsapplication to biomedical research. We highlight a number ofpublished examples of ABM, focusing on work that has combinedexperimental with ABM analyses and how this pairing producesnew understanding. We conclude with suggestions for moving forwardwith this parallel approach.   相似文献   
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This paper presents data from the first major survey of the diversity, biology and fisheries of elasmobranchs in the Persian (Arabian) Gulf. Substantial landings of elasmobranchs, usually as gillnet by-catch, were recorded in Kuwait, Qatar and the Emirate of Abu Dhabi (part of the United Arab Emirates), although larger elasmobranchs from targeted line fisheries were landed in Abu Dhabi. The elasmobranch fauna recorded was distinctive and included species that are undescribed, rare and have a highly restricted known distribution. Numerical abundance was dominated by sharks (c. 80%), of which carcharhinids were by far the most important. The milk shark Rhizoprionodon acutus and whitecheek shark Carcharhinus dussumieri together comprised just under half of all recorded individuals. Around 90% of recorded sharks were small (50-90 cm total length, L(T) ) individuals, most of which were mature individuals of species with a small maximum size (<100 cm L(T) ), although immature individuals of larger species (e.g. Carcharhinus sorrah and other Carcharhinus spp.) were also important. The most frequently recorded batoid taxa were cownose rays Rhinoptera spp., an undescribed whipray, and the granulated guitarfish Rhinobatos granulatus. The first size, sex and maturity data for a wide range of Gulf elasmobranch species are presented (including L(T) at 50% maturity for males of four shark species) and include some notable differences from other locations in the Indo-West Pacific Ocean. A number of concerns regarding the sustainability of the fishery were highlighted by this study, notably that most of the batoid species recorded are classed by the IUCN Red List as vulnerable, endangered, data deficient or not evaluated. Despite their considerable elasmobranch landings, none of the three countries sampled have developed a 'Shark Plan' as encouraged to do so under the FAO International Plan of Action: Sharks. Furthermore, Kuwait and Qatar currently report zero or no elasmobranch landings to the FAO.  相似文献   
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The spiny-tailed lizard, Uromastyx aegyptia microlepis , in Abu Dhabi is parasitized by Haemocystidium apigmentada n. sp., and 2 species of Hepatozoon . The elongate gametocytes of H. apigmentada are 13-19 × 6-9 μm, with length × width (LW) 90-133 μm(2), and L/W ratio 1.56-3.17. Gametocyte dimensions do not differ by sex. Gametocytes are unpigmented. Hepatozoon species 1 has gamonts with a consistently terminal nucleus, with dimensions of 13-16 × 4.5-7 μm, LW of 58-104 μm(2), and L/W ratio of 2.00-3.22. Hepatozoon species 2 gamonts have a broad nucleus at the midbody, and dimensions of 13-15.5 × 5-7 μm, LW of 71-109 μm(2), and L/W ratio of 1.93-3.00.  相似文献   
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