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101.
The data used by Lynch Alfaro et al. (2012a, Journal of Biogeography, 39 , 272–288) and the biogeographical hypothesis postulated by these authors to explain the current distribution of capuchin monkeys were reanalysed including additional cytochrome b data from Sapajus xanthosternos and Sapajus flavius. Our reconstructed phylogeny placed S. xanthosternos in a monophyletic clade representing the most basal lineage of this genus. All analyses indicated polyphyletic arrangements for several capuchin species, suggesting that incomplete lineage sorting has occurred during their evolution. These results also suggest that available molecular data lack adequate variation for accurately resolving species relationships. These results suggest that the divergence of capuchin monkey genera may have occurred in the Atlantic Forest. However, a more conclusive scenario and better resolution of the species tree requires correct identification of species, data from several unlinked nuclear loci from a higher number of individuals per species, and careful analysis of ancient DNA data from museum specimens.  相似文献   
102.
In this work, we show that alternagin-C (ALT-C) and ALT-C PEP, a peptide derived from its sequence, were able to induce angiogenesis in wounded rat skin. A spherical cutaneous excision was made in the back of each animal and treated with three different concentrations of ALT-C or ALT-C PEP. After that, the skin was removed and analyzed to verify the presence of new vessels and the expression of growth factors. ALT-C and ALT-C PEP induced the formation of new vessels and modulated the expression of growth factors, mainly VEGF and FGF1. The expression of VEGF increased and it could be detected up to 7 days after injury. FGF1 also significantly increased, but at a lesser extent than VEGF. In conclusion, the present study shows for the first time the stimulation of angiogenesis in an injured tissue by a disintegrin-like protein and that ALT-C may exert this effect by modulating the expression of growth factors.  相似文献   
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Chrononutrition proposes that nutrients or meal timing per se could affect the circadian clock system, and that the desynchronization of biological rhythms could negatively influence timing and food choices. Research in this area has suggested that mealtime, energy distribution throughout the day, nocturnal eating and food ingestion frequency may influence nutrient metabolism, being associated with metabolic and nutritional diseases. Given the growing amount of evidence linking the circadian clock system to metabolic and nutritional health, circadian organization seems to be clinically important in the understanding of diseases such as obesity and, maybe, in the nutritional treatment of them. Thus, chrononutrition emerges as an important tool to enhance the metabolic and nutritional health of particular population groups (e.g. shift workers) and in the treatment of diseases such as obesity. For this reason, the area needs to be further explored.  相似文献   
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A new karyotype of the genus Oligoryzomys was described for specimens collected in Brazilian Cerrado in Tocantins and Goiás States. Conventional staining, G-, C-banding, and Ag-NOR staining techniques were used for describe this karyotype with 2n=70, AN=74 or 76. The chromosome complement, with the highest diploid number known among Oligoryzomys species, differs from all others previously reported. This small sized Oligoryzomys species can be differentiated from other Brazilian Oligoryzomys not only by chromosomal complement, but also in some morphological attributes. The new species is apparently restricted in distribution and endemic of Brazilian Cerrado, occurring only in Rio Tocantins basin.  相似文献   
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A reversed-phase high-performance liquid chromatography (RP-HPLC) methodology for the qualitative and quantitative analysis of human thyrotropin (hTSH) in CHO cell conditioned medium and in purified preparations has been set up and validated for accuracy, precision and sensitivity. A recovery test indicated a bias of less than 2% and intra-day and inter-day quantitative determinations presented relative standard deviations (RSD) always <7%, while sensitivity was 0.2 microg (RSD=5.6%). The novel methodology was applied to the study of the best cultivation conditions and was able to detect a significant difference in retention time (t(R)) between pituitary and recombinant hTSH, probably reflecting the influence of the heterogeneity of the carbohydrate moiety on the hydrophobic properties of the molecule.  相似文献   
108.
Habitat loss and fragmentation have highlighted the importance of monitoring remaining habitats. For megadiverse groups such as arthropods, of which many species are still being discovered, the use of higher taxonomic levels as substitutes for diversity may be a useful tool. The aim of this study was to evaluate the use of substitute taxonomic resolutions to assess the richness and composition of Laniatores harvestmen (Arachnida: Opiliones). The five resolutions selected were as follows: genus, family, subfamily, indicator taxa and intermediate resolution (combination of genus and species identification levels). In addition, we evaluated whether the diversity substitutes provide good estimates of latitudinal gradients. Nineteen Atlantic Forest sites located along a latitudinal gradient in northeastern Brazil were sampled. We recorded a total of 88 harvestmen species/morpho-species, distributed in 7 families, 15 subfamilies and 36 genera. Genus and intermediate resolution were excellent substitutes for harvestmen species richness. The efficiency differed according to the substitute resolution used. Four resolutions were adequate to replace the harvestmen composition: genus, intermediate resolution, indicator taxa, and subfamily. The number of harvestmen species recorded was significantly different between Seasonal Semideciduous Forest and Costal Atlantic Rainforest. The same relationship was also observed the same relationship was observed when we consider genus and intermediate resolution. Our results suggest the use of genus as a substitute for richness and composition of harvestmen for reducing monitoring costs and providing evaluation in a shorter time and a more practical way.  相似文献   
109.
Biodiversity loss and its effects on humanity is of major global concern. While a growing body of literature confirms positive relationships between biodiversity and multiple ecological functions, the links between biodiversity, ecological functions and multiple ecosystem services is yet unclear. Studies of biodiversity–functionality relationships are mainly based on computer simulations or controlled field experiments using only few species. Here, we use a trait-based approach to integrate plant functions into an ecosystem service assessment to address impacts of restoration on species-rich grasslands over time. We found trade-offs among functions and services when analysing contributions from individual species. At the community level, these trade-offs disappeared for almost all services with time since restoration as an effect of increased species diversity and more evenly distributed species. Restoration to enhance biodiversity also in species-rich communities is therefore essential to secure higher functional redundancy towards disturbances and sustainable provision of multiple ecosystem services over time.  相似文献   
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