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81.
Epidemics of H3N8 and H3N2 influenza A viruses (IAVs) in dogs, along with recognition of spillover infections from IAV strains typically found in humans or other animals, have emphasized the importance of efficient laboratory testing. Given the lack of active IAV surveillance or immunization requirements for dogs, cats, or horses imported into the United States, serotype prediction and whole-genome sequencing of positive specimens detected at veterinary diagnostic laboratories are also needed. The conserved sequences at the ends of the viral genome segments facilitate universal amplification of all segments of viral genomes directly from respiratory specimens. Although several methods for genomic analysis have been reported, no optimization focusing on companion animal strains has been described, to our knowledge. We compared 2 sets of published universal amplification primers using 26 IAV-positive specimens from dogs, horses, and a cat. Libraries prepared from the resulting amplicons were sequenced using Illumina chemistry, and reference-based assemblies were generated from the data produced by both methods. Although both methods produced high-quality data, coverage profiles and base calling differed between the 2 methods. The sequence data were also used to identify the subtype of the IAV strains sequenced and then compared to standard PCR assays for neuraminidase types N2 and N8.  相似文献   
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The stability of the coffee flavor compound furfuryl mercaptan has been investigated in aqueous solutions under Fenton-type reaction conditions. The impact of hydrogen peroxide, iron, ascorbic acid, and ethylenediaminetetraacetic acid was studied in various combinations of reagents and temperature. Furfuryl mercaptan reacts readily under Fenton-type reaction conditions, leading to up to 90% degradation within 1 h at 37 degrees C. The losses were lower when one or more of the reagents was omitted or the temperature decreased to 22 degrees C. Volatile reaction products identified were mainly dimers of furfuryl mercaptan, difurfuryl disulfide being the major compound. In addition, a large number of nonvolatile compounds was observed with molecular masses in the range of 92-510 Da. The formation of hydroxyl and carbon-centered radicals was indicated by electron paramagnetic resonance spectra using alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone or 5-(diethoxyphosphoryl)-5-methyl-1-pyrroline-N-oxide as spin traps. Whereas *OH was generated by Fenton-type reactions, the C-centered radical is probably a secondary product of the reaction of *OH with various organic molecules, the reaction with furfuryl mercaptan appearing to be the most important. No evidence for S-centered radicals was seen in the spin-trapping experiments, but a sulfur-containing radical was detected when measurements were made at 77 K in the absence of spin traps.  相似文献   
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This article reviews the anatomy of the skull and oral cavity in the three amphibian orders. Feeding behavior and feeding physiology are also described. A review is given of reported oral pathology. The pathology is divided into infectious causes (bacterial and parasitic) and noninfectious causes (trauma, neoplasia, and nutritional).  相似文献   
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SUMMARY: Linear regression analysis was used to describe the decline in numbers of Culicoides brevitarsis Kieffer into winter with monthly maximum, average and minimum temperatures at the southern limits to its distribution in New South Wales. From this, low temperature thresholds were derived when C brevitarsis would be absent from the field. The low minimum threshold ± 2 SE (95% Confidence Interval) of 8.1 ± 0.3°C was used with historical temperature data to estimate the last month that the species should occur (March to June) and the mean number of months (2 to 6.5) below the threshold at 17 selected sites. Probability for survival during winter at these sites was estimated from years when the number of consecutive months below the threshold was ≤ 2 months. This varied from zero to 51% depending on the location of the site. Last occurrence was 0.7 months later on average and absolute probabilities for survival ranged from zero to 100% when the temperatures were increased by an arbitrary 2°C.  相似文献   
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Preparations of pathogenesis-related (b) proteins (PRs) from differentNicotiana species, tomato,Gynura aurantiaca, bean, and cowpea were compared to each other and to bean chitinase and a constitutive apple agglutinin by electrophoresis in polyacrylamide gels both in the absence and in the presence of SDS, and by serological double diffusion analysis using antisera against tobacco PRs and bean chitinase. PRs from different plant genera displayed a similar but not identical range of relative mobilities in both native and SDS gels, whereas bean chitinase and apple agglutinin were clearly different. None of the antisera reacted with any of the PR preparations from plant genera other than the one from which the antigen(s) had been derived. Whilst PRs within the genusNicotiana are serologically related and can be identical, PRs from different plant genera seem to be sufficiently different to be considered as genus-specific.  相似文献   
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