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排序方式: 共有1057条查询结果,搜索用时 31 毫秒
91.
Zhu Y Osterlundh I Hultén F Magnusson U 《American journal of veterinary research》2004,65(10):1434-1439
OBJECTIVE: To determine whether concentrations of proinflammatory cytokines, acute-phase proteins, and cortisol differ at parturition among 3 categories of sows (noninoculated, clinically affected and nonaffected following intramammary inoculation with Escherichia coll). ANIMALS: 16 sows. PROCEDURE: Sows were allocated to inoculated (n = 12) or noninoculated (4) groups. Inoculated sows received intramammary administration of E coli (serotype O127) during the 24-hour period preceding parturition. Blood samples were collected from noninoculated and inoculated sows for 3 consecutive days within 3 to 11 days before farrowing and inoculation. Samples were also collected 0, 24, 48, 72, and 96 hours after farrowing and inoculation. Inoculated sows were further categorized as affected (4 sows) or nonaffected (8 sows) based on clinical signs of disease. Serum tumor necrosis factor (TNF)-alpha, plasma interleukin (IL)-6, and serum amyloid A (SAA) concentrations were measured by use of ELISA; serum haptoglobin concentration was assayed by use of a hemoglobin-binding method; and plasma cortisol concentration was determined by use of radioimmunoassay. RESULTS: Plasma or serum concentrations of TNF-alpha, IL-6, and SAA of both categories of inoculated sows were significantly increased by 24 hours after intramammary inoculation of E coli, compared with concentrations in noninoculated sows. Concentrations of serum TNF-alpha and plasma IL-6 were significantly higher in inoculated sows that developed clinical mastitis than in nonaffected inoculated sows. CONCLUSIONS AND CLINICAL RELEVANCE: Concentrations of TNF-alpha and IL-6 are promising markers for the identification of periparturient sows with subclinical coliform mastitis. Identification of such sows should help improve the health and survival of piglets. 相似文献
92.
Jacobsen S Niewold TA Halling-Thomsen M Nanni S Olsen E Lindegaard C Andersen PH 《Veterinary immunology and immunopathology》2006,110(3-4):325-330
The aim of the study was to determine the intraarticular serum amyloid A (SAA) response pattern in horses with inflammatory arthritis. Inflammatory arthritis was induced by injection of lipopolysaccharide (LPS) into the radiocarpal joint of four horses. Serum and synovial fluid (SF) samples were collected before and at 4, 8, 12, 24, 48, 72, 96, and 144 h after injection. Concentrations of SAA were measured by immunoturbidometry, and expression of SAA isoforms was visualized by denaturing isoelectric focusing and Western blotting. The LPS injection caused systemic and local clinical signs of inflammation. Serum amyloid A appeared in serum and SF within 8 h after LPS injection. Isoelectric focusing showed three major SAA bands with apparent isoelectric points (pI) of 7.9, 8.6, and >9.3 in serum and SF. Synovial fluid contained two additional isoforms with highly alkaline apparent pI values (apparent pI value extrapolated from standard curve = 10.0 and 10.2), which were not present in any of the serum samples. In conclusion, intraarticular injection of LPS induced systemic and local inflammatory responses in the horses. By demonstrating SF-specific SAA isoforms the results of the present study suggest that SAA is synthesized locally in the equine inflamed joint, similar to what has been demonstrated in humans previously. The marked local SAA synthesis suggests an important pathophysiological role in inflammatory arthritis. 相似文献
93.
REASONS FOR PERFORMING STUDY: Streptococcus equi is the cause of strangles in horses. To improve diagnostic sensitivity, development and evaluation of DNA-based methods are necessary. OBJECTIVES: To evaluate diagnostic methods and observe the pattern of bacterial shedding during natural outbreaks. METHODS: Two herds with natural outbreaks of strangles were visited over a period of 15 weeks and 323 samples originating from 35 horses investigated. The diagnostic use of a nested PCR test was evaluated using a collection of 165 isolates of Lancefield group C streptococci (species specificity) and swabs from nasal passages or from abscesses from horses infected with S. equi (diagnostic sensitivity). RESULTS: All 45 S. equi isolates tested positive in the nested PCR, whereas no amplicon was formed when testing the other 120 Lancefield group C isolates. A total of 43 samples were collected from 11 horses showing clinical signs of strangles during the study period. The diagnostic sensitivity for PCR test was 45% and 80% for samples from the nasal passages and abscesses, respectively; the corresponding diagnostic sensitivity for cultivation was 18% and 20%. The diagnostic sensitivity was significantly higher for PCR than for bacterial cultivation. Furthermore, the shedding of S. equi in 2 infected horse populations was evaluated. An intermittent shedding period of S. equi of up to 15 weeks was recorded in this part of the study. It was also shown that shedding of S. equi occurred both from horses with and without clinical signs. CONCLUSIONS AND POTENTIAL RELEVANCE: The nested PCR test represents a species-specific and -sensitive method for diagnosis of S. equi from clinical samples. It may, however, be desirable in future to develop detection methods with high diagnostic sensitivity and specificity without the potential problems inherent in nested PCR. 相似文献
94.
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96.
Runno-Paurson Eve Hannukkala Asko Trdan Stanislav Williams Ingrid Koppel Mati Mänd Marika 《植物病害和植物保护杂志》2012,119(2):45-52
Journal of Plant Diseases and Protection - The potato late blight pathogen Phytophthora infestans was collected from a region of Eastern Estonia during a period of seven years (2001–07). In... 相似文献
97.
98.
Sylvie L Benestad Lars Austb? Michael A Tranulis Arild Espenes Ingrid Olsaker 《Veterinary research》2012,43(1):87
Prion diseases such as scrapie in small ruminants, bovine spongiform encephalopathy (BSE) in cattle and Creutzfeldt-Jakob disease (CJD) in man, are fatal neurodegenerative disorders. These diseases result from the accumulation of misfolded conformers of the host-encoded prion protein (PrP) in the central nervous system. To date naturally-occurring PrP free animals have not been reported. Here we describe healthy non-transgenic animals, Norwegian Dairy Goats, lacking prion protein due to a nonsense mutation early in the gene. These animals are predicted to be resistant to prion disease and will be valuable for research and for production of prion-free products. 相似文献
99.
Enterococcus faecalis is a major cause of nosocomial infections in humans and has been linked to severe extra‐intestinal infections in poultry. A zoonotic potential has been suggested and the aim of the present study was to investigate similarities in virulence gene profiles of E. faecalis originating from infections in humans and poultry respectively. A total of 106 isolates of E. faecalis [26 human clinical isolates, 60 poultry clinical isolates (including two small‐colony variants (SCVs) and 20 poultry cloacal isolates] were investigated for presence of seven virulence‐associated genes: ace, asa1, cylA, efaA, EF0591, esp and gelE. For each gene, the PCR‐amplification product was sequenced from one isolate in each group to explore intragenic variations between genes of human and poultry origin. Haemolytic and protease activities were assessed and isolates were assigned a sequence type (ST). Three of the seven genes investigated (ace, efaA and gelE) were present in all isolates. The asa1 was detected in 63/80 and 13/26 isolates of poultry and human origin respectively. For cylA, the numbers were 46/80 and 14/26 respectively. Among poultry isolates, esp and EF0591 were the least frequently observed genes (1/80 and 20/80 respectively); the prevalences among human isolates were 1/26 and 18/26 respectively. A high degree of similarity between genes in human and poultry isolates were confirmed by sequencing of amplification products. None of the cylA‐positive isolates demonstrated haemolytic activity, while the phenotypic expression of gelatinase varied. The ST16 was the only ST shared by human and poultry isolates. The SCV isolates did not show a unique virulence profile or phylogeny. In conclusion, regardless of the distinct phylogenetic background of most E. faecalis isolates of human and poultry origin, we found major similarities in virulence gene profile and gene sequences in isolates from the two sources, supporting the zoonotic risk associated with this organism. 相似文献
100.
Avian pathogenic Escherichia coli (APEC) is associated with several types of extraintestinal infections, collectively known as colibacillosis. A heterogeneous population structure has hindered development of vaccines protective against all APEC. Recently, however, the existence of different APEC subpathotypes have been suggested, which are defined by specific disease syndromes and associated virulence genes. A collection of 14 APEC isolates representing clonal outbreaks of salpingitis accompanied by peritonitis and sepsis were characterized in the present study. All the strains carried large plasmids and the aim of the study was to investigate the similarity of these by sequencing, annotating and comparative analysis to identify potential vaccine targets. In addition, a comparison with gene content of human extraintestinal E. coli (ExPEC) subtypes was conducted. Results obtained demonstrated highly similar plasmid contents of the 14 APEC strains, despite the diversity of their chromosomal background. All 14 APEC carried the colicin V operon and numerous virulence genes. These included iss, traT, hlyF, eitABC, ompT, iroBCDEN, sitABCD, iutA and lucABCD. Several of these are shared with human ExPEC, implicating a possible zoonotic potential. Despite a diverse chromosomal background, it was concluded that the plasmid content of virulence genes are highly similar for the investigated APEC subpathotype. Based on their frequency, protein uniformity and subcellular localization iroN, iutA, iss, traT, ompT and etsC are suggested as vaccine-candidates. Experimental studies are, however, necessary to determine the protective potential of the candidates against the APEC subpathotype characterized by salpingitis, peritonitis and possibly septicaemia. 相似文献