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111.
Collections of arboreal Psocoptera from the four major national parks of Sumatra and from a range of habitats outside the parks (including many of the predominant perennial crops) are appraised for diversity and species overlap between habitats. The most speciose family (Psocidae, 72 morphospecies) is investigated to determine possible surrogacy values in relation to the more taxonomically intractable Other Psocoptera (17 families, 190 morphospecies), in its incidence in 16 different habitats and four main altitudinal zones. Considerable psocid richness persists in disturbed areas, and the values of protected areas and kebun gardening systems in their conservation are noted. 相似文献
112.
We have introduced a series of point mutations into the human opioid receptor-like (ORL1) receptor and characterized them for their ability to constitutively activate G protein-coupled receptor signalling pathways. Among the 12 mutants generated, mutation at Asn133 (N133W) gave increased basal signalling through three separate pathways. N133W increased the basal activity of G14- and G16-dependent pathways by two- to three-fold. The constitutive activity of the mutant was confirmed by the finding that the enhanced activity is dependent on the level of receptor expression. In HEK-293 cells stably expressing N133W, signalling through Gi/o-dependent pathways was also observed. Radioligand binding studies revealed that the affinity for nociceptin of the wild-type ORL1 receptor and the N133W mutant do not differ significantly, suggesting that the ligand binding and signalling functions of constitutively active mutants of G protein-coupled receptors are not necessarily intrinsically linked. In conclusion, our results demonstrate that a mutation in the third transmembrane domain is able to increase the basal signalling activity of the human ORL1 receptor. 相似文献
113.
Effects of Pitfall Trap Spacing on the Abundance, Richness and Composition of Invertebrate Catches 总被引:3,自引:0,他引:3
Pitfall trapping is one of the most commonly used methods to survey surface-active invertebrates, but has many potential biases that may affect the catch of invertebrates. The distance between pitfall traps (inter-trap spacing) is one such factor. The abundance, richness and composition of invertebrate orders, and species of ants and beetles was examined for three commonly used inter-trap spacings (1, 5, 10m) in a grassy-woodland ecosystem in Victoria, Australia. Abundance and composition was not significantly different between treatments for any taxa. A significant difference in richness between treatments was found only for beetles. The 5 and 10m treatments had a significantly higher number of beetle morphospecies than the 1m treatment. Knowledge of such biases, and how subtle variations in trap design affect efficiency, is important for designing invertebrate surveys. 相似文献
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