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Valuable biological information can be obtained by monitoring the movement of organisms. However, the choice of monitoring
method becomes highly restricted when following small organisms (<100 mm), especially in aquatic ecosystems. Stable isotopes
are being increasingly used in this respect but rarely at the local spatial scale, i.e. 10–1000 s of metres. We sought to
identify movement of small fishes between a main river channel and its tributary. Little overlap in isotope baseline was detected
between the two channels despite some temporal variability in δ15N of baseline indicator organisms in the main river. The individuals of two small cyprinid fish species (Leuciscus souffia and Alburnoides bipunctatus) of all the size classes (40–100 mm) caught within the tributary showed considerable heterogeneity in δ15N values. Classification and discriminant analysis on isotope-derived data distinguished two significantly different groups.
Moreover, this result was supported by further sampling of fish caught in the main river (in May and December 2006). Alternative
hypotheses, such as dietary differences, biological factors, temporal shifts and spatial differences in diet, did not explain
δ15N variability. This application of stable isotopes at a relatively small spatial and temporal scales further demonstrates
its potential as a tool for ecologists. 相似文献
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Riccardo Danielli Roberto Patuzzo Anna Maria Di Giacomo Gianfranco Gallino Andrea Maurichi Annabella Di Florio Ornella Cutaia Andrea Lazzeri Carolina Fazio Clelia Miracco Leonardo Giovannoni Giuliano Elia Dario Neri Michele Maio Mario Santinami 《Cancer immunology, immunotherapy : CII》2015,64(8):999-1009
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The existence of an Early Gravettian perforated human tooth at the abri Pataud came to light thanks to the reexamination of the osseous artefacts from the level 5. Even if the method of perforation of this tooth is analogous to the one used to pierce the animal teeth discovered in the same level, this pendant would have a particular meaning. 相似文献
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A Malfitano M Cazzola P Cavalli P G Gobbi M Gorini E Ascari S Perugini 《Basic and applied histochemistry》1980,24(2):101-107
Morphological and cytochemical studies of circulating neoplastic cells were carried out in a patient who presented a preterminal leukaemic phase of Hodgkin's disease (HD). Three types of abnormal cells were found in the peripheral blood: abnormal mononuclear cells, Hodgkin's cells and Reed-Sternberg cells. All neoplastic cells were cytochemically negative to Sudan black B, peroxidase and alkaline phosphatase. Some neoplastic cells were positive to PAS and all were positive to acid phosphatase, alpha-naphthylacetate esterase and beta-glucuronidase. The origin of the neoplastic population in HD is discussed. 相似文献
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