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81.
Varpu Mitikka Risto K. Heikkinen Miska Luoto Miguel B. Araújo Kimmo Saarinen Juha Pöyry Stefan Fronzek 《Biodiversity and Conservation》2008,17(3):623-641
The two main goals of this study are: (i) to examine the range shifts of a currently northwards expanding species, the map butterfly (Araschnia levana), in relation to annual variation in weather, and (ii) to test the capability of a bioclimatic envelope model, based on broad-scale European distribution data, to predict recent distributional changes (2000–2004) of the species in Finland. A significant relationship between annual maximum dispersal distance of the species and late summer temperature was detected. This suggests that the map butterfly has dispersed more actively in warmer rather than cooler summers, the most notable dispersal events being promoted by periods of exceptionally warm weather and southerly winds. The accuracy of the broad-scale bioclimatic model built for the species with European data using Generalized Additive Models (GAM) was good based on split-sample evaluation for a single period. However, the model’s performance was poor when applied to predict range shifts in Finland. Among the many potential explanations for the poor success of the transferred bioclimatic model, is the fact that bioclimatic envelope models do not generally account for species dispersal. This and other uncertainties support the view that bioclimatic models should be applied with caution when they are used to project future range shifts of species. 相似文献
82.
Varpu Vahtera Jyrki Muona 《Cladistics : the international journal of the Willi Hennig Society》2006,22(3):222-229
Miarus is a Holarctic weevil genus with morphologically very similar species, all breeding on Campanula plants or their close relatives. Two European members of this genus, Miarus campanulae (L.), the type species, and Miarus graminis (Bohemann) have recently been split into several new species on the basis of slight external variations. The separation of these new forms has proved impossible and new data was needed. Molecular data were gathered from specimens from a number of locations in Finland, Estonia, Denmark and Sweden. The regions sequenced were mitochondrial CO1 and nuclear ITS2. Both combined and separate datasets were analyzed using the optimization alignment program POY, with parsimony as the optimality criterion. The recently separated Miarus species was found to be indistinguishable from the traditionally recognized form on the basis of this sequence data. On the other hand, the traditionally recognized species were characterized by numerous synapomorphies. Our data suggest that recent studies have underestimated the morphological variation in this genus. We propose that this may also be true for many taxonomically problematic beetle complexes in well‐studied European regions. The idea that molecular evidence will inevitably reveal unnoticed cryptic variation may only apply to poorly known regions. Miarus fennicus Kangas, 1978 is placed as a junior synonym of Miarus campanulae (Linnaeus, 1767) syn. nov . © The Willi Hennig Society 2006. 相似文献
83.
Enzyme-linked immunosorbent assay (ELISA) is compared with the indirect fluorescent antibody test (IFAT), the indirect haemagglutination test (IHAT) and the latex agglutination (LA) test for the detection of toxoplasma antibodies in swine sera. The 100 swine sera examined represent ELISA values from > 0 to 154 EIU. The agreement was highest (0.67) between ELISA and IFAT with an ELISA cut-off value of 30 EIU, and between ELISA and the LA test with an ELISA cut-off value of 50 EIU (0.74). All sera giving < 10 EIU were negative in the other tests, and all those with > 70 EIU were positive in 1, 2 or all of the reference tests. In order to avoid false positive results with ELISA, all sera giving 10–70 EIU should be confirmed with a test which has a good specificity, e.g. IFAT. ELISA is a sensitive test and is highly suitable for the screening of large amounts of samples, but it may be too complicated for screening toxoplasma antibodies in the laboratories of abattoirs. 相似文献
84.
A total of 1847 swine sera obtained from the 10 largest abattoirs slaughtering swine in Finland were examined by ELISA for toxoplasma antibodies. The sample represented 0.64 % of the total number of swine slaughtered in these abattoirs over a period of 2 months. The prevalence of toxoplasma antibodies in swine sera was 2.5 %. 相似文献
85.
K Elenius S Vainio M Laato M Salmivirta I Thesleff M Jalkanen 《The Journal of cell biology》1991,114(3):585-595
We have studied the expression of an integral cell surface proteoglycan, syndecan, during the healing of cutaneous wounds, using immunohistochemical and in situ hybridization methods. In normal mouse skin, both syndecan antigen and mRNA were found to be expressed exclusively by epidermal and hair follicle cells. After incision and subsequent suturing, remarkably increased amounts of syndecan on the cell surfaces of migrating and proliferating epidermal cells and on hair follicle cells adjacent to wound margins were noted. This increased syndecan expression was shown to be a consequence of greater amounts of syndecan mRNA. Induction was observed already 1 d after wounding, was most significant at the time of intense cell proliferation, and was still observable 14 d after incision. The migrating cells of the leading edge of the epithelium also showed enhanced syndecan expression, although clearly less than that seen in the proliferating epithelium. The merging epithelial cells at the site of incision showed little or no syndecan expression; increased syndecan expression, however, was detected during later epithelial stratification. When wounds were left unsutured, in situ hybridization experiments also revealed scattered syndecan-positive signals in the granulation tissue near the migrating epidermal sheet. By immunohistochemical analysis, positive staining in granulation tissue was observed around vascular endothelial cells in a subpopulation of growing capillaries. Induction of syndecan in granulation tissue both at the protein and mRNA levels was temporally and spatially highly restricted. Granulation tissue, which formed in viscose cellulose sponge cylinders placed under the skin of rats, was also found to produce 3.4 and 2.6 kb mRNA species of syndecan similar to that observed in the normal murine mammary epithelial cell line, NMuMG. These results suggest that syndecan may have a unique and important role as a cell adhesion and a growth factor-binding molecule not only during embryogenesis but also during tissue regeneration in mature tissues. 相似文献