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Food selection by the nauplius of Calanus pacificus is definedas the ability to ingest certain kinds of particles in behavioralpreference to others that occur simultaneously in the same environment.Using mixtures of planktonic algae and plastic beads of differentor similar sizes, the nauplii strongly selected the algal cells,consuming them almost exclusively, and at similar rates to thecontrols with only algae. In some cases, however, ingestionrates on the algae were lower than the in the controls, mainlywhen the mixture was composed of algal cells and plastic beadsof smaller sizes able to be captured by the nauplii. Selectionof algal particles was also observed when pollen grains or detrituswere used instead of the plastic beads. Selection behavior alsooccurred when mixtures of two algae of different sizes wereoffered to the nauplii, and it was dependent on the proportionand concentration of both kinds of algae in the mixture. Thepossible effect of particle production on the observed selectivepatterns is discussed. 相似文献
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An alkali-soluble glucan, [α]D + 11° (M potassium hydroxide) having a degree of polymerization of 220, has been isolated from the fruit bodies of the tree fungus Cyttaria harioti Fischer. Periodate oxidation and methylation analysis show that it consists of a highly branched β-D-(1→3)-linked backbone. Hydrolysis of the methylated polysaccharide yielded 2,3,4,6-tetra-O-methyl- (24.5 mol%), 2,4,6-tri-O-methyl-(39.4 mol%), 2,3,4-tri-O-methyl- (8.6 mol%), and 2,4-di-O-methyl-D-glucose (27.5 mol%). Periodate-oxidation results substantiate the methylation studies. The general structural features of the glucan are discussed. 相似文献
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An enzyme immunoassay procedure is described for the identification of major histocompatibility haplotypes and lymphocyte alloantigens in 19 inbred mouse strains. The assay was found to be useful for the genetic monitoring of such mice. 相似文献
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Olga P. Nyssen Angeles Perez‐Aisa Luis Rodrigo Manuel Castro Pilar Mata Romero Juan Ortuo Jesus Barrio Jose Maria Huguet Ines Modollel Noelia Alcaide Alfredo Lucendo Xavier Calvet Monica Perona Barbara Gomez Blas Jose Gomez Rodriguez Pilar Varela Manuel Jimenez‐Moreno Manuel Dominguez‐Cajal Liliana Pozzati Diego Burgos Luis Bujanda Jenifer Hinojosa Javier Molina‐Infante Tommaso Di Maira Luis Ferrer Luis Fernndez‐Salazar Ariadna Figuerola Llucia Tito Cristobal de la Coba Judith Gomez‐Camarero Nuria Fernandez Maria Caldas Ana Garre Elena Resina Ignasi Puig Colm OMorain Francis Megraud Javier P. Gisbert 《Helicobacter》2020,25(5)