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101.
Congenital vertebral malformations are common findings on diagnostic imaging of the vertebral column in “screw‐tailed” brachycephalic dogs. The aims of this study were to evaluate the prevalence and anatomical characteristics of lumbosacral congenital vertebral malformations in French Bulldogs, English Bulldogs, and Pugs presenting for problems unrelated to spinal disease, as well as possible associations with the degree of tail malformation, lumbosacral intervertebral disc herniation, or spondylosis deformans. In this retrospective cross‐sectional study, CT scans of vertebrae L6 to S3 and of the coccygeal vertebrae were reviewed for type of congenital vertebral malformations (hemivertebrae, block vertebrae, lumbosacral transitional vertebrae, and spina bifida), lumbosacral intervertebral disc herniation, lumbosacral spondylosis deformans, and degree of tail malformation. In 76 (51.0%) of the 149 included dogs (53 French Bulldogs, 37 English Bulldogs, and 59 Pugs) at least one type of congenital vertebral malformations was found, with lumbosacral transitional vertebrae being the most common (34.2%). There was a significantly higher prevalence of lumbosacral transitional vertebrae (54.2%) and lower prevalence of hemivertebrae (1.7%) in Pugs compared to English (13.5% and 24.3%, respectively) and French Bulldogs (26.4% and 32.0%, respectively). Tail malformation was significantly more severe in dogs with evidence of hemivertebrae. Congenital vertebral malformations are a common finding in the lumbosacral vertebral column of French Bulldogs, English Bulldogs, and Pugs. These anatomical variances need to be considered when interpreting diagnostic studies and when planning for neurosurgical and neurodiagnostic procedures. Furthermore, this study suggests a possible association between the degree of tail malformation and lumbosacral hemivertebrae.  相似文献   
102.
The influence from 0.5 and 5 mmol L-1 citrate andarginine on nickel sorption in sandy loamy topsoil ofa Mollic Hapludalf has been investigated in order toevaluate the effect of organic complexing agents onnickel retention in soils. Both ligands, which formstrong complexes with nickel, represent common soilsolutes but also serve as models for oxygen andnitrogen donor ligands in fulvic acids and otherorganic soil solutes. In the pH range 4.5–8,sorption edges showed a dramatic decrease in nickelsorption in presence of citrate, but not in thepresence of arginine. These differences were furtherquantified at pH 6.0 through sorption isothermscovering initial nickel concentrations in the range3.4–42.6 μmol L-1. Again, the amounts ofnickel sorbed without and in the presence of 0.5 and5 mmol L-1 arginine were not significantlydifferent, whereas 0.5 and 5 mmol L-1 citratereduced sorption by 50 to 90%. The ligand effectscould be expressed through variation of the Freundlichaffinity constant K. The results indicate thattrivalent positively charged nickel-arginine complexes(NiH3arg2 3+) are sorbed to cationexchange sites, while in the presence of citrate sitesfor the bonding of monovalent negatively chargednickel-citrate complexes (Nicit-) are sparse.  相似文献   
103.
Free oligosaccharides are key components of human milk and play multiple roles in the health of the neonate, by stimulating growth of selected beneficial bacteria in the gut, participating in development of the brain, and exerting antipathogenic activity. However, the concentration of oligosaccharides is low in mature bovine milk, normally used for infant formula, compared with both human colostrum and mature human milk. Characterization of bovine milk oligosaccharides in different breeds is crucial for the identification of viable sources for oligosaccharide purification. An improved source of oligosaccharides can lead to infant formula with improved oligosaccharide functionality. In the present study we have analyzed milk oligosaccharides by high-performance liquid chromatography chip quadrupole time-of-flight mass spectrometry and performed a detailed data analysis using both univariate and multivariate methods. Both statistical tools revealed several differences in oligosaccharide profiles between milk samples from the two Danish breeds, Jersey and Holstein-Friesians. Jersey milk contained higher relative amounts of both sialylated and the more complex neutral fucosylated oligosaccharides, while the Holstein-Friesian milk had higher abundance of smaller and simpler neutral oligosaccharides. The statistical analyses revealed that Jersey milk contains levels of fucosylated oligosaccharides significantly higher than that of Holstein-Friesian milk. Jersey milk also possesses oligosaccharides with a higher degree of complexity and functional residues (fucose and sialic acid), suggesting it may therefore offer advantages in term of a wider array of bioactivities.  相似文献   
104.
176 horseradish accessions from the Nordic countries Denmark, Finland, Norway and Sweden were analysed to estimate the level of genetic diversity and to propose conservation strategies for this cultivated plant. Most of the accessions were collected in old gardens of the Nordic countries but selections from European countries and Danish breeding lines were also included in the study. Since horseradish is mainly vegetative propagated the genetic diversity has been assumed to be small. However, using the AFLP method with three primer combinations we revealed a significant genetic diversity among Nordic horseradish. The analysis yielded 65 polymorphic bands and we found an overall diversity index of 0.5 (Shannon–Weaver). The highest diversity was found among the Finnish accessions followed by the Danish accessions. An overall AMOVA analysis indicated that 90 % of the variation could be explained by among accession variation. The AFLP data assigned the different accessions into groups that corresponded with their country of origin. A closer relationship was observed between the Swedish, Danish and some of the Norwegian accessions while the Finnish accessions separated more clearly from the other three countries. A possible explanation for the diversity is that horseradish probably has been introduced to the Nordic countries at many occasions during a long period of time.  相似文献   
105.
Bluetongue virus (BTV) is an arthropod-borne pathogen that causes an often fatal, hemorrhagic disease in ruminants. Different BTV serotypes occur throughout many temperate and tropical regions of the world. In 2006, BTV serotype 8 (BTV-8) emerged in Central and Northern Europe for the first time. Although this outbreak was eventually controlled using inactivated virus vaccines, the epidemic caused significant economic losses not only from the disease in livestock but also from trade restrictions. To date, BTV vaccines that allow simple serological discrimination of infected and vaccinated animals (DIVA) have not been approved for use in livestock. In this study, we generated recombinant RNA replicon particles based on single-cycle vesicular stomatitis virus (VSV) vectors. Immunization of sheep with infectious VSV replicon particles expressing the outer capsid VP2 protein of BTV-8 resulted in induction of BTV-8 serotype-specific neutralizing antibodies. After challenge with a virulent BTV-8 strain, the vaccinated animals neither developed signs of disease nor showed viremia. In contrast, immunization of sheep with recombinant VP5 - the second outer capsid protein of BTV - did not confer protection. Discrimination of infected from vaccinated animals was readily achieved using an ELISA for detection of antibodies against the VP7 antigen. These data indicate that VSV replicon particles potentially represent a safe and efficacious vaccine platform with which to control future outbreaks by BTV-8 or other serotypes, especially in previously non-endemic regions where discrimination between vaccinated and infected animals is crucial.  相似文献   
106.
Attine ants engage in a quadripartite symbiosis with fungi they cultivate for food, specialized garden parasites, and parasite-inhibiting bacteria. Molecular phylogenetic evidence supports an ancient host-pathogen association between the ant-cultivar mutualism and the garden parasite. Here we show that ants rear the antibiotic-producing bacteria in elaborate cuticular crypts, supported by unique exocrine glands, and that these structures have been highly modified across the ants' evolutionary history. This specialized structural evolution, together with the absence of these bacteria and modifications in other ant genera that do not grow fungus, indicate that the bacteria have an ancient and coevolved association with the ants, their fungal cultivar, and the garden parasite.  相似文献   
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Influences of phosphorus and nitrogen on uranium and arsenic accumulation in Lemna gibba L. were investigated in the laboratory hydroponic cultures and in the field pot experiments. The initial uranium and arsenic concentrations in solutions for the hydroponic cultures were 1000 μ g l?1 each, while in situ trials used tailing water containing 198.7 ± 20.0 μ g U l?1 and 75.0 ± 0.4 μ g As l?1 at a former uranium mine in eastern Germany. A test of three PO4 3? concentrations (0.01, 13.6 and 40.0 mg l?1) in the hydroponic cultures, highest uranium accumulated in L. gibba under the culture with highest PO4 3?. Significant differences in uranium accumulation were between 0.01 mg l?1 and 13.6 mg l?1 PO4 3? cultures only (ANOVA p = 0.05). In the field, addition of 40.0 mg l?1 PO4 3? increased the bioaccumulation of uranium significantly. Contrary, high PO4 3? concentrations suppressed the bioaccumulation of arsenic in both the laboratory and the field. The bioaccumulation of both uranium and arsenic increased slightly with the increase of NH4 + concentration. However, high NH4 + concentrations reduced the yield in the control experiments. The concentration of uranium rose temporarily to 856.0 ± 294.0 μ g l?1, while the concentration of arsenic sunk slightly and temporarily immediately after amending the tailing waters with 40 mg l?1 PO4 3?. The speciation of uranium in the tailing water was modelled with geochemical code PhreeqC, which predicted that uranyl carbonate species dominated before addition of phosphates, but after increasing the PO4 3? concentrations, uranyl phosphates species became dominant. Addition of NH4 + to the tailing water had negligible influence on free available uranium and arsenic concentrations. Thus, manipulations to enhance uranium and arsenic attenuation by L. gibba has limitation when the amendments interact with other elements including the contaminants in the milieu, and when the target contaminants have antagonistic behaviour in the tailing water.  相似文献   
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