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Dag Inge Våge Ingrid Olsaker Helge Klungland Luis Gomez-Raya Sigbjørn Lien 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(1):56-63
A male bovine linkage map was constructed using six half-sib families of the Norwegian Cattle population. The family material consisted of six sires and 285 sons, with the number of sons per sire ranging from 32 to 71. Of the 288 markers analysed, 261 were anonymous microsatellites and 27 were coding genes. Eleven of the coding genes were mapped by a two-step procedure involving intron/exon sequencing in the six sires and development of polymerase chain reaction-based methods for efficient genotyping in heterozygous families. Linkage analysis including both informative and non-informative sons was performed in order to obtain unbiased estimates of recombination fractions. The autosomal genome length of the Norwegian Cattle Map (NCM) was estimated as 2682 cM, with an average interval of 12.5 cM. The map provides sufficient marker density for scanning the whole bovine genome to locate quantitative trait loci. The large number of common markers between NCM and previously published maps will contribute to the comparison and integration of bovine maps. 相似文献
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Harald Volden Weiert Velle Øystein V. Sjaastad Arnfinn Aulie Odd Magne Harstad 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(1):35-45
The main purpose of this study was to examine sources of variation in free amino acids (FAA) in the rumen and their relative contribution to the total duodenal amino acid supply. Six cannulated lactating dairy cows fed three concentrate mixtures differing in ruminally degradable intake protein (101, 114 and 134 g kg-1 dry matter) at two levels of intake (19.3 vs 9.8 kg dry matter day-1 相似文献
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Frøydis T. Gillund Lise Nordgaard Thomas Bøhn Odd Gunnar Wikmark Heidi Sjursen Konestabo Angelika Hilbeck 《Potato Research》2013,56(4):293-324
The deliberate release of any genetically modified (GM) organism in the European Union requires an environmental risk assessment (ERA) prior to commercialisation, including impact assessment on nontarget organisms. We report from two expert workshops where a newly developed selection procedure for identification of ecologically relevant testing organisms was applied to the case of a GM potato with increased resistance to late blight, planned for cultivation in southern Scandinavia. Species known to contribute to important ecological functions in the receiving environment were selected in a stepwise procedure, to arrive at a practical number of ecologically relevant species that are likely to be exposed to the transgene and suitable for experimental testing. Four ecological functional categories were identified: herbivory and disease transmission, natural enemies, ecological soil processes and pollination. Among these, relevant nontarget species were identified for herbivores and soil living pathogens, natural enemies and decomposers/beneficial soil organisms. Out of a total of 16 herbivores, 17 soil-living pathogens, 49 natural enemies and 14 decomposers/beneficial soil organisms in the initial lists, 8 herbivores, 10 soil-living pathogens, 15 natural enemies and 11 decomposers/beneficial soil organisms were identified as possible testing organisms, based on ecological criteria. These findings are highly relevant for determining the scope and structure of an ERA of this type of GM potato. The selection procedure could not be completed because of insufficient information about tissue- and developmental stage-specific expression levels of the transgenic products for this particular GM potato. Thus, the case study illustrates some of the difficulties and knowledge gaps that limit the relevance and quality of ERA of GM plants. 相似文献
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Tony Christopeit Kersti ?verb? U. Helena Danielson Inge W. Nilsen 《Marine drugs》2013,11(11):4279-4293
The screening of extracts from marine organisms is a widely used strategy to discover new drug leads. A common problem in the screening process is the generation of false positive hits through unspecific effects from the complex chemical composition of the crude extracts. In this study, we explored a combination of a fluorescence resonance energy transfer (FRET) based activity assay and a surface plasmon resonance (SPR) based binding assay to avoid this problem. An aqueous extract was prepared from rest raw material of the Norwegian spring spawning herring, and further fractionated by methanol solubility and solid phase extraction. FRET based activity assays were used to determine the influence of each extract on the activity of different proteases. Several extracts showed more than 50% inhibition. The inhibition mechanisms were elucidated by SPR based competition experiments with known inhibitors. For the secreted aspartic proteases 1, 2, 3 and HIV-1 protease, the results indicated that some extracts contain inhibitors interacting specifically with the active site of the enzymes. The study shows that a combination of an activity assay and an SPR based binding assay is a powerful tool to identify potent inhibitors in marine extracts. Furthermore, the study shows that marine vertebrates offer an interesting source for new bioactive compounds, although they have rarely been explored for this purpose. 相似文献
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Lovisa Stjernman Forsberg Jon-Petter Gustafsson Dan Berggren Kleja Stig Ledin 《Water, air, and soil pollution》2008,194(1-4):331-341
A 20-month column experiment investigated leaching of Al, Cu, Mn, Ni, Zn, Cd and Pb during sulphide oxidation in mine tailings with and without sewage sludge (SS) amendment. Leachate pH decreased gradually in all columns during the experiment, irrespective of treatment, due to sulphide oxidation. As the degree of sulphide oxidation, and thus the pH trajectory, differed between replicates (n?=?3), running data for each column used are reported separately and the relationships between sulphide oxidation, metal leaching and treatment in each column compared. Mean pH in the columns correlated negatively with total amounts of leached SO4 2-. In the beginning of the experiment the leachate concentrations of Al, Cu, Zn, Ni and Pb were higher in SS-treated columns due to high initial concentrations of dissolved organic carbon. As leaching proceeded, however, the amounts of Al, Cu, Mn and Ni leached from the columns were closely related to the degree of sulphide oxidation in each column, i.e. to its mean pH. There were no statistically significant differences between treatments regarding the total amounts of metals leached and thus addition of sewage sludge to the tailings appeared to play a minor role for metal leaching patterns. Peak concentrations of Al and Cu in the leachate from untreated tailings and of Zn in the leachate from both untreated and SS-treated tailings at pH 4 exceeded national background values for groundwater. 相似文献
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Lejeune B Lorenz I 《The Canadian veterinary journal. La revue veterinaire canadienne》2008,49(4):386-388
Two cases where clinical findings suggestive of proximal ileus resulting in hypokalemic and hypochloremic alkalosis are presented. Ultrasonographs showed distension of the sigmoid flexure along the ventral border of the liver and between the serosal lamellae of the greater omentum in the flank, allowing exact preoperative obstruction localization. 相似文献
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