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PAOLA MENSI ALDO LATTES BIANCAMARIA MACARIO SEBASTIANO SALVIDIO CRISTINA GIACOMA EMILIO BALLETTO 《Zoological Journal of the Linnean Society》1992,104(4):293-311
Phylogenetic relationships within the Euro-Mediterranean stock of the Rana temporaria species group (R. temporaria, R. iberica, R. cameranoi, R. macrocnemis, R. holtzi, R. dalmatina, R. graeca, R. latastei) were studied by (1) morphometric analysis, (2) osteological study and (3) electrophoresis. The three data sets were analysed independently and phenograms and cladograms examined for congruent patterns. The tree resulting from electrophoretic analysis is the most clearly resolved (and being also compatible with the other two) is assumed to represent the most likely phylogeny of the Mediterranean brown frogs. Patterns indicated by electrophoretic data matched the molecular clock-hypothesis. This suggests that the first split of the main stock of Mediterranean brown frogs separated ancestors of Rana temporaria and R. iberica from the others during the Late Pleistocene. A second split occurred separating the ancestors of what are currently the other big-bodied and the small-bodied brown frogs. The relationships between and within the three main stocks are discussed in the context of biogeographical and geological data. 相似文献
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CRETELLA MASSIMO; SCILLITANI GIOVANNI; TOSCANO FRANCESCO; TURELLA PAOLA; PICARIELLO ORFEO; CATAUDO ADRIANA 《Journal of Molluscan Studies》1994,60(1):9-17
The external morphology of soft parts of the rare Patella ferrugineaGmelin, 1791 is described, and its relationships with P. caerulea,P. rustica and P. ulys-siponensis are investigated on both morphologicaland electrophoretic grounds. Soft part morphology is a gooddiscriminative tool, but of little help in detecting affinities.Electrophoretic data on 19 presumptive loci suggest that P.rustica is the closest species to P. ferruginea, whereas P.caerulea and P. ulyssiponensis are clustered separately. Meanobserved heterozyg-osities arc higher in P. ferruginea and P.rustica. It is concluded that in case of subdivision of thegenus Patella L., 1758, P. ferruginea and P. rustica shouldbe placed together in the subgenus Patellastra Mon-terosato,1884. (Received 6 January 1993; accepted 23 February 1993) 相似文献
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ESTER PICCINNI PAOLA IRATO LETIZIA CAVALLINI DIETER AMMERMANN 《The Journal of eukaryotic microbiology》1992,39(5):589-593
ABSTRACT The effects of cadmium on three ciliates are reported here. Cultures of Stylonychia lemnae, Stylonychia notophora and Oxytricha granulifera were treated with different doses of Cd according to tolerance. The two species of Stylonychia are very sensitive to the metal, white O. granulifera tolerates higher doses. Adding 50 μM of Cd to the medium did not damage cells. The accumulated metal is almost totally present in the particulate fraction after day 3. Two Cd-Zn linking fractions were separated from the soluble fraction of culture treated on day 1. The first protein linking 17 μg Cd/mg showed an ultraviolet absorption spectrum similar to that of Cd-thioneins. Preliminary amino acid analyses indicated that it contained 13% cysteine. The second protein, linking 60 μg Cd/mg, was a glycoprotein. Its ultraviolet absorption spectrum and amino acid analysis showed that this binding protein was far from being a metallothionein: its cysteine content was very low and aromatic and cyclic residues were present. This Cd-linking compound seems to be unique, since it was very different both from metallothioneins and chelatins isolated by other protozoa. The protective role of these chelating proteins is discussed. 相似文献
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Rice flooding negatively impacts root branching and arbuscular mycorrhizal colonization,but not fungal viability 总被引:1,自引:0,他引:1
PAOLA BONFANTE 《Plant, cell & environment》2014,37(3):557-572
Rice is mostly cultivated in wetlands, where arbuscular mycorrhization (AM) is reported to decrease. The mechanisms regulating such events are largely unknown. Rice uninoculated and inoculated with Rhizophagus irregularis were grown in dry and flooded conditions, allowing also for the transfer of plants from one water regime to the other. Roots were sampled at different times, from 7 to 35 d post‐inoculation (dpi). The morphological and molecular parameters (root branching, aerenchyma formation, mycorrhizal colonization, AM marker gene expression) were evaluated. Root branching was more pronounced in dry conditions, and such phenotype was enhanced by the fungus. In wetlands, the colonization level was comparable till 21 dpi, when the mycorrhization then decreased, paralleled by an increase in aerenchyma. Expression of the fungal transporters was comparable under the two conditions. The root apparatus, when shifted from one water regime to the other, rapidly adapted to the new condition, revealing a marked plasticity. The reversibility of the AM rice symbiosis was also mirrored by expression changes of plant marker genes. The results demonstrate that the water regime is the driving force that regulates AM colonization under flooding conditions, by directly influencing root architecture and anatomy, but without impacting the basic AM functionality. 相似文献
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Tethya norvegica Bowerbank, 1872, a northern species generally synonymized with T. aurantium . has been studied from Scotland, The Faroes, Norway, Iceland, Spitzbergen and Bear Island. The species is redescribed and its North East Atlantic distribution delimited Tethya norvegica is compared, on the basis of morphometric and electrophoretic features, with T. aurantium and F.citrina . Morphological, morphometric and electrophoretic data suggest that I norvegica is a distinct biological species. 相似文献
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