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941.
942.
Long-distance bird migration is fueled by energy gathered at stopover sites along the migration route. The refueling rate
at stopover sites is a determinant of time spent at stopovers and impacts the overall speed of migration. Refueling rate during
spring migration may influence the fitness of individuals via changes in the probability of successful migration and reproduction
during the subsequent breeding season. We evaluated four plasma lipid metabolites (triglycerides, phospholipids, β-OH-butyrate,
and glycerol) as measures of refueling rate in free-living semipalmated sandpipers (Calidris pusilla) captured at non-breeding areas. We described the spatial and temporal variation in metabolite concentrations among one winter
site in the Dominican Republic and four stopover sites in the South Atlantic and Mid-Atlantic Coastal Plain regions of North
America. Triglycerides and β-OH-butyrate clearly identified spatial variation in refueling rate and stopover habitat quality.
Metabolite profiles indicated that birds had higher refueling rates at one site in the Mid-Atlantic Coastal Plain than at
three sites on the South Atlantic Coastal Plain and one site in the Dominican Republic. Temporal variation in lipid metabolites
during the migration season suggested that male semipalmated sandpipers gained more weight at stopovers on the South Atlantic
Coastal Plain than did females, evidence of differential migration strategies for the sexes. Plasma lipid metabolites provide
information on migration physiology that may help determine stopover habitat quality and reveal how migratory populations
use stopover sites to refuel and successfully complete long-distance migrations. 相似文献
943.
González-Ittig RE Salazar-Bravo J Polop JJ Gardenal CN 《Molecular ecology resources》2008,8(6):1466-1468
The rodent Oligoryzomys longicaudatus or long-tailed pygmy rice rat is the reservoir of the aetiological agent of the hantavirus pulmonary syndrome in southern Argentina and Chile. We characterize 11 polymorphic microsatellite loci which would be useful for studies on microgeographical population structure in the species. Amplification of these loci in 42 individuals from four natural populations revealed four to 21 alleles per locus, and values of observed heterozygosities ranging from 0.371 to 0.896. Cross-species amplifications showed that some of the primers designed may be useful for other species of the genus Oligoryzomys. 相似文献
944.
Bonilla CA Crossa A Jave HO Mitnick CD Jamanca RB Herrera C Asencios L Mendoza A Bayona J Zignol M Jaramillo E 《PloS one》2008,3(8):e2957
Aim
To describe the incidence of extensive drug-resistant tuberculosis (XDR-TB) reported in the Peruvian National multidrug-resistant tuberculosis (MDR-TB) registry over a period of more than ten years and present the treatment outcomes for a cohort of these patients.Methods
From the Peruvian MDR-TB registry we extracted all entries that were approved for second-line anti-TB treatment between January 1997 and June of 2007 and that had Drug Susceptibility Test (DST) results indicating resistance to both rifampicin and isoniazid (i.e. MDR-TB) in addition to results for at least one fluoroquinolone and one second-line injectable (amikacin, capreomycin and kanamycin).Results
Of 1,989 confirmed MDR-TB cases with second-line DSTs, 119(6.0%) XDR-TB cases were detected between January 1997 and June of 2007. Lima and its metropolitan area account for 91% of cases, a distribution statistically similar to that of MDR-TB. A total of 43 XDR-TB cases were included in the cohort analysis, 37 of them received ITR. Of these, 17(46%) were cured, 8(22%) died and 11(30%) either failed or defaulted treatment. Of the 14 XDR-TB patients diagnosed as such before ITR treatment initiation, 10 (71%) were cured and the median conversion time was 2 months.Conclusion
In the Peruvian context, with long experience in treating MDR-TB and low HIV burden, although the overall cure rate was poor, a large proportion of XDR-TB patients can be cured if DST to second-line drugs is performed early and treatment is delivered according to the WHO Guidelines. 相似文献945.
One of the main goals of protected areas, especially National Parks, is biodiversity conservation. Taking into account the multiple negative impacts that allochthonous animals can cause in an ecosystem, it is important to know and track the introductions in order to take efficient management measures to enhance biodiversity conservation. We study the origin of an Ichthyosaura alpestris population in Peñalara Massif within the Guadarrama National Park, Central Spain. To accomplish this goal, we used nine microsatellite markers and sequences from 16S and ND4 genes. Both mitochondrial DNA and microsatellite analyses showed the close relationship between Peñalara and Asturian populations, despite their geographical distance, confirming the allochthonous origin of this population. Interestingly, more than one introduction event seems to have occurred with individuals from Lago Ercina and Pozos de Lloroza populations participating in the founding of the Peñalara population. Due to predation, competition and transmission of diseases enhanced by its ongoing expansion, I. alpestris population might be considered a threat to Peñalara biodiversity. We advise an efficient population control to conserve the biodiversity within the Guadarrama National Park and an update of the position of this population in the Spanish indexes and list of species. 相似文献
946.
Andrés Fernández-Loras Saioa Fernández-Beaskoetxea Elena Arriero Matthew C. Fisher Jaime Bosch 《European Journal of Wildlife Research》2017,63(6):99
Fungal pathogens have evolved a broad suite of strategies aiming at evading the host immune response. Amphibians are globally infected by the panzootic chytrid fungus Batrachochytrium dendrobatidis (Bd) and, while robust innate immune defences have been characterised, there is little evidence for the existence of effective adaptive immunity. We determine the immune response of the common midwife toad following challenge by Bd as larvae. Immune function was described for both the cell-mediated and antibody-mediated immune responses following infectious challenge as larval amphibians. While there were no significant differences in the ratio of neutrophils/lymphocytes between infected and uninfected individuals, early exposure of tadpoles to Bd significantly dampened the levels of circulating immunoglobulins (IgM and IgY) in the serum of juveniles after metamorphosis. Our results show that Bd immunosuppresses amphibians when infection occurs as larvae with potentially broad effects on the remodelling of immunity during metamorphosis. 相似文献
947.
Ozhan Simsek Pembe Curuk Fatma Aslan Melda Bayramoglu Tolga Izgu Jaime A. Teixeira da Silva Yildiz Aka Kacar Yesim Yalcin Mendi 《Biochemical genetics》2017,55(1):87-102
The genus Cyclamen (family Myrsinaceae) contains about 20 species, most of which occur in the Mediterranean region. Turkey has critically important Cyclamen genetic resources. Molecular characterization of plant materials collected from different regions of Turkey in which Cyclamen species grow naturally, namely Adana, Antalya, Ayd?n, Mu?la, ?zmir, Denizli, Kahramanmara?, Osmaniye, Eski?ehir, Trabzon, and Rize provinces, was performed using RAPD and SRAP markers. DNA was successfully amplified by 30 RAPD primers and 14 SRAP primer pairs. Among the 470 bands generated by the RAPD primers, 467 were polymorphic. The number of bands detected by a single primer set ranged from 11 to 22 (average of 15.6). The percentage polymorphism was 99.3 % based on the RAPD data. In the SRAP analysis, a total of 216 bands were generated, showing 100 % polymorphism. The number of bands detected by a single primer set ranged from 9 to 22 (average of 15.4). All data were scored and UPGMA dendrograms were constructed with similar results in both marker systems, i.e., different species from nine provinces of Turkey were separated from each other in the dendrograms with the same species being clustered together. 相似文献
948.
Marcos Méndez Chabier de Jaime Manuel A. Alcántara 《Journal of Insect Conservation》2017,21(5-6):907-915
949.
Postbreeding elevational movements of western songbirds in Northern California and Southern Oregon
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Andrew Wiegardt Jared Wolfe C. John Ralph Jaime L. Stephens John Alexander 《Ecology and evolution》2017,7(19):7750-7764
Migratory species employ a variety of strategies to meet energetic demands of postbreeding molt. As such, at least a few species of western Neotropical migrants are known to undergo short‐distance upslope movements to locations where adults molt body and flight feathers (altitudinal molt migration). Given inherent difficulties in measuring subtle movements of birds occurring in western mountains, we believe that altitudinal molt migration may be a common yet poorly documented phenomenon. To examine prevalence of altitudinal molt migration, we used 29 years of bird capture data in a series of linear mixed‐effect models for nine commonly captured species that breed in northern California and southern Oregon. Candidate models were formulated a priori to examine whether elevation and distance from the coast can be used to predict abundance of breeding and molting birds. Our results suggest that long‐distance migrants such as Orange‐crowned Warbler (Oreothlypis celata) moved higher in elevation and Audubon's Warbler (Setophaga coronata) moved farther inland to molt after breeding. Conversely, for resident and short‐distance migrants, we found evidence that birds either remained on the breeding grounds until they finished molting, such as Song Sparrow (Melospiza melodia) or made small downslope movements, such as American Robin (Turdus migratorius). We conclude that altitudinal molt migration may be a common, variable, and complex behavior among western songbird communities and is related to other aspects of a species’ natural history, such as migratory strategy. 相似文献
950.
Leo Jaime Filgueira de Oliveira Bruno Sampaio Sant’Anna Gustavo Yomar Hattori 《Invertebrate reproduction & development.》2017,61(4):290-296
The bioecology of freshwater prawns can be understood by studying their reproductive biology. Thus, the aim of this paper was to determine and compare the reproductive potential of four freshwater caridean prawns collected in the Amazon region. For two years, we captured females of Macrobrachium brasiliense, Palaemon carteri, Pseudopalaemon chryseus and Euryrhynchus amazoniensis from inland streams in the municipality of Itacoatiara (AM). At the laboratory, we measured the biometric variables total length, carapace length, abdomen length and total weight, and recorded the number of eggs (NE) by direct counting. There was a significant difference for all variables between the species. The females of M. brasiliense were the most abundant and had the largest sizes and NE. However, the fecundity index shows that P. carteri has the highest reproductive potential of the four species. Despite the differences in size and weight, all the species showed low fecundity, which is a characteristic of continental palemonidean K strategist prawns. 相似文献