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531.
The p53 tumor suppressor gene (TP53) is the most frequently altered gene in human cancer. Mutation of the gene has been shown to be an important mechanism of p53 pathway inactivation in a variety of human brain tumors, particularly those of astrocytic origin. Genomic DNA from a series of 37 glial and 51 nonglial canine brain tumors was sequenced to determine the frequency of TP53 gene mutations involving exons 3-9. Exonic mutations were found in 3 of 88 tumors (3.4%) and specifically in 1 of 18 astrocytic tumors (5.5%). This is markedly lower than that reported in comparable human tumors, suggesting that alternative mechanisms of p53 inactivation are likely to be present if p53 function contributes significantly to oncogenesis in canine brain tumors.  相似文献   
532.
Suzanne Higgins  Saskia D. Keesstra  Žydrė Kadziuliene  Lionel Jordan-Meille  David Wall  Alessandra Trinchera  Heide Spiegel  Taru Sandén  Andreas Baumgarten  Johannes L. Jensen  Juliane Hirte  Frank Liebisch  Susanne Klages  Philipp Löw  Katrin Kuka  Maarten De Boever  Karoline D'Haene  Sevinc Madenoglu  Hesna Özcan  Wieke Vervuurt  Janjo de Haan  Willem van Geel  Bo Stenberg  Pascal Denoroy  Rok Mihelič  Alar Astover  Raquel Mano  Cristina Sempiterno  Fatima Calouro  Giuseppe Valboa  Helena Aronsson  Tore Krogstad  Stanislav Torma  Jose Gabriel  Peter Laszlo  Nils Borchard  Bartosz Adamczyk  Anna Jacobs  Beata Jurga  Bożena Smreczak  Bruno Huyghebaert  Morgan Abras  Raimonds Kasparinskis  Eloise Mason  Claire Chenu 《European Journal of Soil Science》2023,74(5):e13422
The European Commission has set targets for a reduction in nutrient losses by at least 50% and a reduction in fertiliser use by at least 20% by 2030 while ensuring no deterioration in soil fertility. Within the mandate of the European Joint Programme EJP Soil ‘Towards climate-smart sustainable management of agricultural soils’, the objective of this study was to assess current fertilisation practices across Europe and discuss the potential for harmonisation of fertilisation methodologies as a strategy to reduce nutrient loss and overall fertiliser use. A stocktake study of current methods of delivering fertilisation advice took place across 23 European countries. The stocktake was in the form of a questionnaire, comprising 46 questions. Information was gathered on a large range of factors, including soil analysis methods, along with soil, crop and climatic factors taken into consideration within fertilisation calculations. The questionnaire was completed by experts, who are involved in compiling fertilisation recommendations within their country. Substantial differences exist in the content, format and delivery of fertilisation guidelines across Europe. The barriers, constraints and potential benefits of a harmonised approach to fertilisation across Europe are discussed. The general consensus from all participating countries was that harmonisation of fertilisation guidelines should be increased, but it was unclear in what format this could be achieved. Shared learning in the delivery and format of fertilisation guidelines and mechanisms to adhere to environmental legislation were viewed as being beneficial. However, it would be very difficult, if not impossible, to harmonise all soil test data and fertilisation methodologies at EU level due to diverse soil types and agro-ecosystem influences. Nevertheless, increased future collaboration, especially between neighbouring countries within the same environmental zone, was seen as potentially very beneficial. This study is unique in providing current detail on fertilisation practices across European countries in a side-by-side comparison. The gathered data can provide a baseline for the development of scientifically based EU policy targets for nutrient loss and soil fertility evaluation.  相似文献   
533.
Bacteriologic detection of Salmonella spp. from feces of animals admitted to Veterinary Teaching Hospital of the Faculty of Veterinary Medicine, University of Montréal, in Saint-Hyacinthe was carried out during a 1-year period to estimate the prevalence of bovine and equine salmonellosis. Prevalence at the time of hospitalization was quite low: 1.4% in cattle and 1.7% in horses. Incidence was 15.1 cases/100 animal/year in cattle and 38.7 cases/100 animal/year in horses. Serotype typhimurium was the most prevalent in both species. In cattle, cases were evenly distributed over the year. In horses, a recrudescence of cases and a obviousness of transmission were apparent in April 1996.  相似文献   
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