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111.
In the western Palaearctic, the Mediterranean zone is an important region where taxa and genes of thermophilous organisms are preserved during glacial stages and new clades are generated. This is achieved through the existence of refugia over Mediterranean Europe and North Africa, where organisms persisted and continued to evolve during the cold phases. However, it is not clear in detail how these refugia function for the maintenance of ancestral taxa, the evolution of new taxa, and as launching pads during postglacial colonizations of northern Europe. One outstanding issue is the incongruence of findings from different marker systems. For the butterfly Maniola jurtina, morphometry and allozyme data analyzed for populations scattered over Europe and North Africa show congruent patterns for Sicily and the Maghreb but produce discrepant results for the Italian mainland. This discrepancy between allozyme and morphological data can be explained by recent gene flow in the wake of postglacial range expansions and shifts. It is evident that colonization histories are far more complex than originally considered. We highlight different aspects of colonization and evolutionary history emerging from the joint use of different marker systems and advocate multiple uses of different markers in paleobiogeographic reconstructions to explore evolutionary events and colonization pathways. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 103 , 571–577.  相似文献   
112.
Abstract. Six cattle that had earlier exposure to Dermatobia hominis were infested experimentally with first-instar larvae of the parasite. Skin biopsies taken at intervals were studied in wax and in plastic sections. The avidin-biotin-peroxidase method was used to detect the presence and localization of host immunoglobulins (Igs) G and M and antigens of first and second instar larvae of Dermatobia hominis. The larvae penetrated actively through the skin and migrated towards the subcutaneous tissues. The great numbers of eosinophils suggest that they are the most important cell in mediating damage to D.hominis larvae. The immunoglobulins bound only to dead or moulting larvae in which access to binding sites may have been altered. This could represent a morphological manifestation of a mechanism that protects larvae from the host immune response. Large amounts of soluble antigens detected along the fistulous tract may be important in the maintenance of this tract by disturbing the normal cicatrization process.  相似文献   
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Types of oreal and oreotundral disjunctions in the western Palearctic   总被引:1,自引:0,他引:1  
The cyclic changes of the Pleistocene between cold and warm periods resulted in antagonistic responses within two different groups of organisms: one expanding during the warm periods and retracting during the cold phases and another with opposed responses. The latter group is composed of so-called arctic and alpine species. These species have recently become the focus of phylogeographical research. However, we still lack a comprehensive characterization of the different types of alpine and arctic-alpine disjunctions in the western Palearctic. Such an overview might facilitate the selection of different model species to test the different patterns of disjunctions for congruences revealing their past distribution. Therefore, we list all alpine and arctic-alpine disjunction types of the western Palearctic using butterflies and moths as a model group. We distinguish between (1) endemics of the Alps (α) with strongly restricted and (β) with broader distributions; (2) alpine disjunct species (α) with perialpine disjunctions and (β) with a wide western Palearctic distribution; (3) oro-Mediterranean species; and (4) arctic-alpine disjunct species. These types of distributions and further subtypes are exemplified using chorological data of butterfly and moth species. In this context, we discuss the intraspecific differentiation and the differentiation among sibling-species within and among disjunct parts of the distribution area. We also formulate hypotheses of the distribution patterns during the last ice age which might best explain the actual patterns. Finally, we suggest some case studies of genetic analyses to test the above mentioned hypotheses.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 415–430.  相似文献   
114.
A primary carcinoid tumour of the breast in a 66-year-old man was diagnosed by fine-needle aspiration cytology. The nature of the lesion was proved by histochemical and immunocytochemical studies. The importance of a conclusive diagnosis is discussed and the value of immunocytochemical analysis as an aid to cytomorphologic diagnosis is demonstrated.  相似文献   
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The biogeography of the western Palearctic has been intensively studied for more than a century. Recent advances in genetics have allowed the testing of old theories based on distribution patterns, although these analyses are obviously restricted to a reduced number of specific genetic data sets. On the other hand, an increased knowledge on the distributions of species and advances in computer capacities have allowed more detailed biogeographical analyses based on species presence/absence. In the present study, we selected the Odonata as the study group. For all 162 species native to the western Palearctic, we compiled their respective presence or absence in 97 predefined biogeographical regions. Using cluster analyses and principal component analyses, both based on Jaccard similarity coefficients, we analysed the differentiation among these regions and species. In subsequent analyses, the data set was reduced to the Zygoptera, Anisoptera, and the western Palearctic endemics. All analyses consistently showed different faunal regions and faunal elements. In particular, the (1) western and (2) eastern Mediterranean; (3) Central and (4) Northern Europe; and (5) the British Isles were invariably found in all cases. Although the two major Mediterranean regions were characterized by several endemic faunal elements, Northern Europe and the British Isles lacked such elements, but were characterized by faunal compositions strongly deviating from the rest of the western Palearctic region. Moderate differences between Zygoptera and Anisoptera existed, with the latter more clearly redrawing the Mediterranean refuge areas, whereas the former reflected to a greater extent the postglacial expansion patterns from these regions. In general, our findings underline the old biogeographical theories, but refine especially our understanding of the Atlanto‐ and Ponto‐Mediterranean region. Central Europe, comprising the area with the highest species numbers of our whole study region, unravels as a crossroad of postglacial immigrations, but might also represent a region of in situ glacial survival. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 177–195.  相似文献   
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