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551.
Canine parvovirus--a review of epidemiological and diagnostic aspects, with emphasis on type 2c 总被引:1,自引:0,他引:1
Canine parvovirus type 2 (CPV-2) emerged in late 1970s causing severe epizootics in kennels and dog shelters worldwide. Soon after its emergence, CPV-2 underwent genetic evolution giving rise consecutively to two antigenic variants, CPV-2a and CPV-2b that replaced progressively the original type. In 2000, a new antigenic variant, CPV-2c, was detected in Italy and rapidly spread to several countries. In comparison to the original type CPV-2, the antigenic variants display increased pathogenicity in dogs and extended host range, being able to infect and cause disease in cats. Epidemiological survey indicate that the newest type CPV-2c is becoming prevalent in different geographic regions and is often associated to severe disease in adult dogs and also in dogs that have completed the vaccination protocols. However, the primary cause of failure of CPV vaccination is interference by maternally derived immunity. Diagnosis of CPV infection by traditional methods has been shown to be poorly sensitive, especially in the late stages of infections. New diagnostic approaches based on molecular methods have been developed for sensitive detection of CPV in clinical samples and rapid characterisation of the viral type. Continuous surveillance will help assess whether there is a real need to update currently available vaccines and diagnostic tests. 相似文献
552.
Lo Cantore P Iacobellis NS De Marco A Capasso F Senatore F 《Journal of agricultural and food chemistry》2004,52(26):7862-7866
Essential oils were extracted from the fruits of Coriandrum sativum L. and Foeniculum vulgare Miller var. vulgare (Miller) and assayed in vitro for antibacterial activity to Escherichia coli and Bacillus megaterium, bacteria routinely used for comparison in the antimicrobial assays, and 27 phytopathogenic bacterial species and two mycopathogenic ones responsible for cultivated mushroom diseases. A significant antibacterial activity, as determined with the agar diffusion method, was shown by C. sativum essential oil whereas a much reduced effect was observed for F. vulgare var. vulgare oil. C. sativum and F. vulgare var. vulgare essential oils may be useful natural bactericides for the control of bacterial diseases of plants and for seed treatment, in particular, in organic agriculture. The significant antibacterial activity of essential oils to the bacterial pathogens of mushrooms appears promising. 相似文献
553.
Cinzia Podda Francesco Palmas Giacomo Frau Giovanna Chessa Jacopo Culurgioni Riccardo Diciotti Nicola Fois Andrea Sabatini 《水产资源保护:海洋与淡水生态系统》2020,30(8):1638-1648
- The European eel, Anguilla anguilla, is a catadromous and migratory species of commercial importance. Its complex life cycle results in its exposure to many risk factors, which have resulted in stock declines across all life stages since the 1970s.
- The temporal recruitment dynamics of juvenile eels (glass eels and elvers) were investigated in a small Mediterranean estuary (Sardinia, Italy). The composition of the population and the monthly and seasonal variations in the abundances of juvenile eels was assessed over 78 sampling events (from February 2017 to February 2018). Furthermore, the effects of abiotic variables on the abundances of glass eels and elvers were investigated using generalized additive models (GAMs).
- Glass eels had the greatest abundance during the winter months, whereas elvers had the greatest abundance during spring. Modelling revealed that the abundance of glass eels was mostly explained by the combined effects of water temperature (12.3–14.5 °C), tidal coefficient (40–110 cm), moon phase, season, and river mouth condition, whereas the abundance of elvers was associated with water temperature (14–21 °C), dissolved oxygen content (>7 mg/L), and season. These results suggest that the annual recruitment of juvenile eels occurs throughout the year, with clear seasonal migration dynamics.
- The use of multiple statistical approaches allowed us to identify the importance of several environmental variables in regulating the recruitment dynamics, providing useful information for conserving eel stocks through the restoration of the natural flow regime and the connectivity between freshwater habitats and the sea.
554.
Martella V Elia G Decaro N Di Trani L Lorusso E Campolo M Desario C Parisi A Cavaliere N Buonavoglia C 《Veterinary microbiology》2007,121(1-2):56-63
In December 2005, equine influenza virus infection was confirmed as the cause of clinical respiratory disease in vaccinated horses in Apulia, Italy. The infected horses had been vaccinated with a vaccine that contained strains representatives from both the European (A/eq/Suffolk/89) and American (A/eq/Newmarket/1/93) H3N8 influenza virus lineages, and the H7N7 strain A/eq/Praga/56. Genetic characterization of the hemagglutinin (HA) and neuraminidase (NA) genes of the virus from the outbreak, indicated that the isolate (A/eq/Bari/2005) was an H3N8 strain closely related to recent representatives (Kentucky/5/02-like) of the American sub-lineage Florida, that was introduced in Italy through movement of infected horses from a large outbreak described in 2003 in United Kingdom. Strain A/eq/Bari/2005 displayed 9 amino acid changes in the HA1 subunit protein with respect to the reference American strain A/eq/Newmarket/1/93 contained in the vaccine. Four changes were localized in the antigenic regions C-D and likely accounted for the vaccine failure. 相似文献
555.
Virginie Barberet Elke Schreurs Nathalie Rademacher Dagmar Nitzl Olivier Taeymans Luc Duchateau Jimmy H Saunders 《Veterinary radiology & ultrasound》2008,49(3):273-276
We assessed factors that affected ultrasonographic visualization of the pylorus, duodenal papilla, pancreas, adrenal glands, and jejunal and medial iliac lymph nodes in the dog. An abdominal ultrasonographic examination was performed on 100 canine patients, equally divided between two facilities. The pylorus was visible in 64% of the dogs, the major duodenal papilla in 42%, the left pancreatic lobe in 56%, the body of the pancreas in 60%, the right pancreatic lobe in 87%, the left adrenal gland in 91%, the right adrenal gland in 86%, the medial iliac lymph nodes in 54%, and the jejunal lymph nodes in 51%. The parameters that negatively influenced the visibility of these organs were the presence of air or food in the gastrointestinal tract (pancreas, duodenal papilla), age (lymph nodes), and body weight (pancreas, duodenal papilla). The parameters that positively influenced their visibility were the presence of air or food in the gastrointestinal tract (lymph nodes), body weight (lymph nodes), body condition score (right adrenal gland), and inherent image quality (left pancreatic lobe). There was a significant difference between the two institutes for the visualization of the pylorus, pancreas, and lymph nodes, which was probably related to different body positions used for scanning in each institution. 相似文献
556.
Detection of Single‐feature Polymorphisms (SFPs) between two tomato varieties and their application in defining the introgressions of resistance loci 下载免费PDF全文
Justyna Milc Alessandro Infantino Maria Aragona Nicola Pecchioni 《Plant Breeding》2015,134(2):226-232
The objectives of the study were to (i) demonstrate that the hybridization data from microarrays can yield information on sequence variation between two inbred lines, an introgression line ‘Mogeor’ and its genetic background ‘Moneymaker’; (ii) characterize, by means of the identified SFPs, the introgressed genomic segments of ‘Mogeor’, carrying resistance genes; and (iii) deliver a set of genetically anchored SFPs potentially useful for breeding. In this work, the GeSNP software was used to identify SFPs in tomato using Affymetrix data from a previous experiment. Sequencing of 12 putative polymorphism‐containing amplicons yielded a SFP probe set validation rate of 90%. In total, 92 Gene Models putatively harbouring SFPs were identified, distributed as following: 61 Gene Models on chromosome 9, and one to eight on the remaining tomato chromosomes apart from chromosomes 7, 8 and 12. Newly discovered SFPs from microarray data can thus provide not only useful information for definition of introgressed genomic regions, but also identification of candidate genes and new markers for MAS. 相似文献