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排序方式: 共有352条查询结果,搜索用时 18 毫秒
61.
62.
A double mycotic infection, caused by Aspergillus fumigatus and a zygomycete-like organism, was histopathologically demonstrated in the lungs of a 12-week-old chicken. A. fumigatus was isolated, but the zygomycete was not. 相似文献
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The present study is part of a series of investigations aimed at characterizing the "enzootic pneumonia" phenomenon in rabbits, both from the clinical-epidemiological and the pathophysiological point of view. All affected rabbits included in this study showed an acute injury to pulmonary microvasculature, similar to changes reported in pulmonary infections caused by Gram-negative bacteria. Similar alterations were not found in the control rabbits. The clinical and morphological findings revealed certain similarities between the Enzootic Pneumonia Syndrome of rabbits and Adult Respiratory Distress Syndrome (ARDS) of man. Therefore, it is suggested that, just as in the human syndrome, heterophils (PMN) are directly involved in the pathogenesis of the process. Many of the similarities noted between the two syndromes would make it possible to postulate the natural disease in rabbits as an eventual animal model suitable for extrapolating data to humans. 相似文献
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Jimenez M Guzman AP Azuara E Garcia O Mendoza MR Beristain CI 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(1):57-63
Porophyllum tagetoides is an annual warm-weather herb that has an intense typical smell. Its leaves are commonly used in soup preparation and traditional
medicine for treatment of inflammatory diseases. Its volatile compounds and antioxidant properties were evaluated in crude,
aqueous and ethanol leaf extract and an oil emulsion using different antioxidant assays in vitro, such as: DPPH radical scavenging activity, redox potential, polyphenol content, reducing power and optical density. A high
antioxidative activity was found when comparing leaves with stems. The crude extract from leaves showed a very high reducing
power (2.88 ± 0.20 O.D.) and DPPH radical-scavenging activity (54.63 ± 4.80%), in concordance with a major concentration of
vitamin C (23.97 ± 0.36 mg/100 g). Instead, the highest polyphenol content (264.54 ± 2.17 mg GAE/g of sample) and redox potential
(561.23 ± 0.15 mV) were found by the ethanol and aqueous extract, respectively. Aldehydes and terpenes such as nonanal, decanal,
trans-pineno, β-myrcene and D-limonene were the major volatiles found. This study suggests that Porophyllum tagetoides extracts could be used as antioxidants. 相似文献
68.
Molecular basis of quinolone resistance in Escherichia coli from wild birds 总被引:2,自引:0,他引:2 下载免费PDF全文
P.A. Jiménez Gómez J.E. García de los Ríos A. Rojas Mendoza P. de Pedro Ramonet R. García Albiach M.P. Reche Sainz 《Canadian journal of veterinary research》2004,68(3):229-231
Nine quinolone resistant (minimal inhibitory concentration [MIC] was > 32 microg/mL for nalidixic acid, > 1 microg/mL for ciprofloxacin) isolates of Escherichia coli have been found in wild birds with septicemia. All of the isolates were aerobactin positive. The mechanisms of resistance were characterised by sequencing the quinolone resistance-determining region (QRDR) of the gyrA, gyrB, parC, and parE genes. Sequence analysis of the gyrA gene in all isolates identified only 1 nucleotide substitution at codon Serine-83 for Leucine-83. Sequence analysis of the gyrB, parC, and parE QRDR genes revealed no mutations in any of the isolates. This study was conducted to determine the importance of these genes in the susceptibility of E. coli strains isolated from wild birds to quinolones. 相似文献
69.
Inhibitory effect of African swine fever virus on lectin-dependent swine lymphocyte proliferation 总被引:1,自引:0,他引:1
S González C Mendoza J M Sánchez-Vizcaino F Alonso 《Veterinary immunology and immunopathology》1990,26(1):71-80
The incubation of swine peripheral blood mononuclear cells (PBMC) with African swine fever (ASF) virus preparations strongly inhibited the proliferative response of lymphocytes to PHA and other lectins. The inhibition, which persisted after inactivation of the virus by UV radiation, was dependent upon the dose and the time that virus preparations were present in cultures. When virus preparations were fractionated by ultracentrifugation, the inhibitory activity resulted to be soluble, whereas no activity was found in the sedimented viral fraction. However, the preincubation during 4 days of this sedimented fraction with swine PBMC, before the addition of the mitogen, restored the inhibitory activity. The results obtained suggest that the inhibition is mediated by one or more soluble factors released by swine PBMC after coincubation with ASF virus in a time dependent process. These factors show a molecular weight between 40 and 80 kDa by gel filtration chromatography. The inhibitory activity described in the present paper is an indication of inhibition of lymphocyte function produced by ASF virus which can help to understand how this virus escapes from the host immune system. 相似文献
70.
NW TOMKINS NN JONSSON MP YOUNG AN GORDON KA McCOLL 《Australian veterinary journal》1997,75(10):722-723
On the basis of clinical signs and histological findings eight 9-month-old male rusa deer ( Cervus timorensis ) were diagnosed with sheep associated-malignant catarrhal fever. Following a variable course involving rectal temperatures around 40.5°C, depression, inappetence, diarrhoea, corneal opacity and hypopyon all animals died or were euthanased over a 5-week period. Severe multifocal vasculitis, mainly periglomerular and in the arcuate vessels were consistent histological findings which in the past have been adequate to confirm clinical diagnosis of sheep associated-malignant catarrhal fever. A nested poly-merase chain reaction test has been used to detect a sheep associated-malignant catarrhal fever PRC product, 238 base-pairs in size, in DNA extracted from lymphocyte preparations. The result supported the diagnosis of sheep associated-malignant catarrhal fever in these deer. 相似文献