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排序方式: 共有1818条查询结果,搜索用时 281 毫秒
991.
Rep-PCR Based Genomic Fingerprinting of Isolates of Leptosphaeria maculans from Poland 总被引:1,自引:0,他引:1
Malgorzata Jedryczka Thierry Rouxel Marie-Hélène Balesdent 《European journal of plant pathology / European Foundation for Plant Pathology》1999,105(8):813-823
Leptosphaeria maculans, the ascomycete fungus which causes blackleg disease of oilseed rape, has been considered for a long time as a single species divided into aggressive and non-aggressive pathogenicity groups which differ in their economic importance. However, the development of accurate biochemical and molecular characterisation methods has demonstrated that the world-wide L. maculans population actually comprises at least two species. The aim of this research was to assess the ability of rep (repetitive element based)-PCR genomic fingerprinting methods, initially developed for bacterial identification, to characterise a collection of 90 isolates of L. maculans from Poland, in comparison with reference isolates from the IBCN (International Blackleg of Crucifers Network) collection. REP (repetitive extragenic palindromic)-, ERIC (enterobacterial repetitive intergenic consensus)-, and BOX primers for rep-PCR genomic fingerprinting, and primers derived from LMR1, a L. maculans specific repeated element, were tested. Rep-PCR and LMR1-based analyses were able to discriminate the different components of the species complex and to evaluate the genetic diversity within each member of the complex. These analyses suggested that Polish populations of L. maculans mainly belong to the non-aggressive species, rather than the aggressive species which is prevalent in Western Europe, Canada and Australia. 相似文献
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The distribution of gastrointestinal disorders in mink in Danish farms is presented based on data collected in a longitudinal design. The time at risk was from weaning in June until pelting in November. The occurrence of gastrointestinal disorders after weaning of the mink kits together with the distribution within farms was studied. The period of highest risk was in the months immediately after weaning (July and August). More than 17% of the farms recorded GI disorders among ≥10% of pairs of animals. A multilevel statistical analysis showed that besides the effect of time after weaning, a significant part of the variation in the incidence could be attributed to the farm and feed-producer. The potential for bias is discussed. 相似文献
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Hallstein Grnstl 《Acta veterinaria Scandinavica》1980,21(3):415
Four groups of lambs, about 6 months old, were given 4 different immunosuppressiva (prednisolone, cyclophosphamide, niridazole and gestagene hormones), 1 substance to each group. After this treatment the 4 groups together with a 5th group of the same size, were infected with Listeria monocytogenes (Lm).None of the animals developed clinical listeric encephalitis. The level of antibodies differed between the groups. The group not given any immun osuppressivum reached the highest antibody titres, the group given gestagene hormones had the lowest titres and the other groups ranged somewhere inbetween. All the groups except the group treated with niridazole had a strong delayed hypersensitivity reaction against Lm. The effects of the treatment upon some blood components are also described.Further studies are necessary to establish the effect of various immunosuppressiva, especially gestagene hormones. 相似文献
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Balogh N Krausz F Lévai P Ribiczeyné PS Vajdovich P Gaál T 《Acta veterinaria Hungarica》2002,50(3):343-356
This study investigated lipid peroxidation (LPO) changes during intestinal ischaemia-reperfusion with and without deferoxamine or L-arginine treatment. White Wistar rats were allotted into four groups as follows: sham-operated (Group SOP), ischaemia-reperfusion only (Group I/R), I/R with deferoxamine (Group D) or L-arginine (Group A) treatment. Concentration of thiobarbituric acid reactive substances (TBARS), overall concentration of malondialdehyde and 4-hydroxy-alkenals (LPO586), activities of superoxide dismutase (SOD) and glutathione peroxidase (GPX) of the jejunal homogenates were determined. The same analytes except LPO586 were assayed in RBC haemolysates. Measurements of ferric reducing ability (FRAP), total antioxidant status (TAS) and nitric oxide (NO) concentrations of plasma samples were also completed. The only significant change observed in the SOP group was an increased SOD activity after the ischaemic period. In the I/R group significant increase of intestinal LPO586 concentration was observed during hypoxia that was followed by similar changes in intestinal and RBC TBARS and plasma FRAP values upon reperfusion. In Group D the intestinal TBARS and LPO586 concentrations were significantly lower while FRAP and NO concentrations were significantly higher compared to the I/R group. At the same time RBC TBARS concentration and GPX activity significantly decreased within Group D. In Group A the intestinal LPO586 concentration was significantly lower than in the I/R group whilst RBC TBARS concentration showed a similar pattern. Plasma FRAP and NO concentration showed similar changes to those seen in Group D. It is concluded that I/R increased the LPO in the intestinal tissue and altered some parameters of plasma and RBCs, too. Deferoxamine treatment prevented these effects, while the usefulness of L-arginine remained doubtful. 相似文献
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Percutaneous ultrasound-guided cholecystocentesis was performed on 13 healthy beagle dogs to determine whether percutaneous ultrasound-guided cholecystocentesis in the dog was a feasible and safe procedure. Clinical, laboratory and ultrasonographic examinations were done at 0 and 10 minutes, in the 2nd and 16th hour, and on the 7th day. They included a detailed physical examination of the mucous membranes, cardiorespiratory system and abdominal organs. Laboratory examinations of the blood consisted of a complete blood count, determination of packed cell volume (PCV), haemoglobin (Hb), total plasma protein (TPP), parameters of haemostasis including prothrombin time (PT), activated partial thromboplastin time (APTT), and enzyme activities reflecting hepatobiliary function, i.e. aspartate aminotransferase (AST), alanine aminotransferase (ALT), and gamma-glutamyltransferase (GGT). Ultrasonographic findings of the gallbladder (size, shape, wall, content) and appearance of the biliary tract and the surrounding cranial intraabdominal organs were also evaluated. Percutaneous ultrasound-guided cholecystocentesis was performed easily during the study, and dogs tolerated well the procedure performed without anaesthesia. All laboratory parameters of the blood remained within normal limits throughout the study. However, some follow-up values, i.e. PCV, TPP, APTT and ALT, demonstrated statistically significant differences when compared to baseline measurements, which might reflect the effect of 24-hour fasting before the experiment, as well as day-to-day metabolic fluctuations due to feeding and water supply during the study. There were no visible signs of bleeding from the liver, bile leakage from the gallbladder or accumulation of free peritoneal fluid during repeated ultrasonographic examinations. Percutaneous ultrasound-guided cholecystocentesis seems to be an important diagnostic procedure in canine gallbladder diseases and can be used safely and easily to gain gallbladder bile for diagnosis of bacterial cholecystitis or for investigating hepatobiliary function in the dog. 相似文献