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821.
Expressed sequence tag data were generated from complementary DNA libraries created from cephalothorax, eyestalk, and pleopod tissue of the black tiger shrimp (Penaeus monodon). Significant database matches were found for 48 of 83 nuclear genes sequenced from the cephalothorax library, 22 of 55 nuclear genes from the eyestalk library, and 6 of 13 nuclear genes from the pleopod library. The putative identities of these genes reflected the expected tissue specificity. For example, genes for digestive enzymes were identified from the cephalothorax library and genes involved in the visual and neuroendocrine system from the eyestalk library. A few sequences matched anonymous EST or genomic sequences, and others contained mini-satellite or microsatellite repeat sequences. The remainder, 31 from the cephalothorax library, 25 from the eyestalk library, and 5 from the pleopod library, were sequences of high nucleotide complexity with no matches in any database searched and thus may represent novel genes. Received February 12, 1999; accepted April 13, 1999  相似文献   
822.
Porphyrin methyl esters and the isomers of uroporphyrin and heptacarboxylic porphyrin were separated by high-performance liquid chromatography. Isocoproporphyrin was also separated from coproporphyrin. By slight modifications to the solvent mixture, the separation of all biological polycarboxylic porphyrins was achieved. These separations were made possible through the high efficiency of 10- or 5-μm particle-size Radial-PAK cartridges, which have been used in the separation of porphyrins in various excreta and tissues in a number of porphyrias.  相似文献   
823.
This study describes the use of a section of a replanted riparian wildlife corridor by Lumholtz's Tree‐kangaroo (Dendrolagus lumholtzi) (referred to here as LTK) on the Atherton Tablelands in north‐east Queensland, Australia. Selection of plants for replanting had been adjusted to the seasonally inundated clay‐rich and acid soils of the site, and, in some cases, with the aim to establish wind breaks which resulted in a plant composition of this section that differs from known LTK habitats. Through semi‐regular daily observations of individual LTKs over eight years, it was found that LTKs were most commonly recorded on Tallowwood (Eucalyptus microcorys), Rose Gum (E. grandis), Caribbean Pine (Pinus caribaea) and Bunya Pine (Araucaria bidwillii) which were planted as wind breaks in the 1950s and 1980s. On a section planted in 1998, it was found that LTKs used certain tree species more frequently than would have been expected from the relative number in which these species had been planted. This may be associated with certain structural features of the used tree species. The presence of these structural habitat features may allow LTKs to establish home ranges within the restored habitat. Home ranges were calculated for four females, and it was found that they did not differ in size from those reported from other LTK habitats. However, home ranges showed extensive overlaps. The study reveals that LTK will colonise replanted habitat and may be adaptable in its spatial requirements in a restored landscape.  相似文献   
824.
Candida albicans is a medically important pathogen, and recognition by innate immune cells is critical for its clearance. Although a number of pattern recognition receptors have been shown to be involved in recognition and phagocytosis of this fungus, the relative role of these receptors has not been formally examined. In this paper, we have investigated the contribution of the mannose receptor, Dectin-1, and complement receptor 3; and we have demonstrated that Dectin-1 is the main non-opsonic receptor involved in fungal uptake. However, both Dectin-1 and complement receptor 3 were found to accumulate at the site of uptake, while mannose receptor accumulated on C. albicans phagosomes at later stages. These results suggest a potential role for MR in phagosome sampling; and, accordingly, MR deficiency led to a reduction in TNF-α and MCP-1 production in response to C. albicans uptake. Our data suggest that pattern recognition receptors sample the fungal phagosome in a sequential fashion.  相似文献   
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