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11.
Ferrero ME Blanco-Aguiar JA Lougheed SC Sánchez-Barbudo I De Nova PJ Villafuerte R Dávila JA 《Molecular ecology》2011,20(12):2628-2642
The Pleistocene climatic oscillations promoted the diversification in avian species during the last glacial period. The red‐legged partridge (Alectoris rufa, Family Phasianidae) has a large natural distribution extending from the Mediterranean to humid temperate zones. However, the genetic structure for this species is unknown. The present study investigates the phylogeography, genetic structure and demographic history of A. rufa across its distribution, employing both mitochondrial DNA control region sequences and nuclear microsatellite loci. Our results propose that this species was greatly affected by Pleistocene glaciations. The mismatch analyses suggest that the current populations resulted from post‐glacial expansion and subsequent differentiation resulting in five diagnosable genetic clusters: Southwestern, Central‐eastern, Northwestern, Balearic and French and Italian. Further, we found evidence of three glacial refugia within the currently recognized Iberian glacial refugium. The intraspecific structure revealed by both maternal and biparental phylogeographic analyses was not resolved in the phylogenetic analyses. Based on all considerations, we recommended that five management units be recognized. 相似文献
12.
Using the mitochondrial non‐coding region I, it was shown that the two Spanish Lampetra planeri populations (Cares–Deva and Olabidea–Ugarana) correspond to different genetic units. The Cares–Deva population is probably a recent offshoot of Lampetra fluviatilis, being the Olabidea–Ugarana population less diverse and of older origin. 相似文献
13.
The lethal effect on human cancer cells was studied under three types of treatment: A) an ELF pulsed sinusoidal of 50 Hz electromagnetic field (PEMF) with amplitudes between 10 and 55 mT; B) the field and a cytostatic agent (actinomycin-C); and C) the field, the cytostatic agent, which has a photodynamic effect, and exposure to a halogen lamp. The results show a decreasing vitality of human K-562 and U-937 cancer cells in suspension with each additional treatment. Combination with other parameters as hyperthermia and/or hyperacidity could yield high killing rates by this noninvasive method. 相似文献
14.
L‐asparaginase isolated from Streptomyces ansochromogenes promotes Th1 profile and activates CD8+ T cells in human PBMC: an in vitro investigation 
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下载免费PDF全文 15.
Luis A. Espínola Elie Abrial Ana P. Rabuffetti Nadson R. Sim
es Mario L. Amsler Martin C.M. Blettler Maria F. Eurich Aldo R. Paira 《Ecohydrology》2020,13(2)
This study examines the effects of the flow and flood pulses on spatial dispersion of fish assemblages in the floodplain of the Paraná River in Argentina. We tested the hypothesis that high water levels and greater lateral connectivity promote fish dispersal and spatial homogenization of assemblage structure. We sampled four sites during different phases of the annual hydrologic cycle from 2010 to 2016. Water surface in the area was estimated during each phase. We computed multivariate statistics and estimates of ß‐diversity to analyse assemblage variations in relation to hydrological phases. Three hydrological phases were defined: low flow pulses (water levels between 2.3 and 3.2, approximately 10% of the floodplain covered by water), high flow pulses (between 3.2 and 4.5, from 11 to 84%), and floods (> 4.5 m, more than 84%). Although difference between high flow pulses and flood was not significant, ß‐diversity values for these stages were higher than for low flow pulses. This suggests that floods and high flow pulses increase the spatial variability of fish assemblages, whereas homogenization processes occur later during low flow periods. This work provides further knowledge about the flood homogenization effect in a large unregulated floodplain where lateral connectivity still plays a significant role on ecological structuring processes. 相似文献
16.
Estimates of population size are frequently used in conservation. Volunteer‐conducted surveys are often the only source of information available, but their reliability is unclear. We compare data from a weakly structured national bird atlas collected by volunteer surveyors free to choose where and when to visit with data from an independent suite of monitoring surveys that used a stratified sampling design. We focus on the Mount Lofty Ranges, South Australia, a region that has lost most of its native vegetation. Both datasets comprise several thousand 20‐min 2‐ha searches carried out between 1999 and 2007. The atlas dataset reported more species, and covered habitats more comprehensively, but showed greater variability in the temporal and spatial distribution of survey effort. However, after we restricted the atlas dataset to native eucalypt woodlands, reporting rates from the two schemes were very strongly correlated. The structured surveys tended to record more species that are normally detected by call and the unstructured surveys recorded more species using edges and open habitats. Minimum population estimates from the two datasets agreed very well. The strength of concordance depended on whether overflying birds were included, highlighting the importance of distinguishing such records in future surveys. We conclude that appropriate calibration using selected regional surveys, including surveys to estimate absolute densities, can enable volunteer‐collected and weakly structured atlas data to be used to generate robust occupancy and minimum population estimates for many species at a regional scale. 相似文献
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Single chain fragment variables (ScFvs) have been extensively employed in studying the protein-protein interactions. ScFvs derived from phage display libraries have an additional advantage of being generated against a native antigen, circumventing loss of information on conformational epitopes. In the present study, an attempt has been made to elucidate human chorionic gonadotropin (hCG)-luteinizing hormone (LH) receptor interactions by using a neutral and two inhibitory ScFvs against hCG. The objective was to dock a computationally derived model of these ScFvs onto the crystal structure of hCG and understand the differential roles of the mapped epitopes in hCG-LH receptor interactions. An anti-hCG ScFv, whose epitope was mapped previously using biochemical tools, served as the positive control for assessing the quality of docking analysis. To evaluate the role of specific side chains at the hCG-ScFv interface, binding free energy as well as residue interaction energies of complexes in solution were calculated using molecular mechanics Poisson-Boltzmann/surface area method after performing the molecular dynamic simulations on the selected hCG-ScFv models and validated using biochemical and SPR analysis. The robustness of these calculations was demonstrated by comparing the theoretically determined binding energies with the experimentally obtained kinetic parameters for hCG-ScFv complexes. Superimposition of hCG-ScFv model onto a model of hCG complexed with the 51-266 residues of LH receptor revealed importance of the residues previously thought to be unimportant for hormone binding and response. This analysis provides an alternate tool for understanding the structure-function analysis of ligand-receptor interactions. 相似文献
19.
MA Schuler 《Molecular ecology》2012,21(17):4157-4159
20.