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871.
872.
Hamid ME Alla KM Ahmed SS El Shiekh AE Ibrahim KE 《Journal of the South African Veterinary Association》2006,77(2):90-91
We describe a rare case of a concurrent demodectic and sarcoptic mange in a 2-year-old heifer in Khartoum, Sudan. The lesions were massive lumps of granulomatous tumour-like dermatitis with thick, nodular folds mainly covering the head, neck and shoulders. Histopathological examination of the lesions revealed the presence of both Demodex bovis and Sarcoptes scabiei. The animal died regardless of the anti-parasitic treatment it received. 相似文献
873.
Olivier PA Dippenaar SM Khalil LF Mokgalong NM 《The Onderstepoort journal of veterinary research》2000,67(2):135-140
The phylogeny of the genus Udonella has been disputed for quite some time, but recent phylogenetic analysis of molecular data confirms that the genus is a monopisthocotylean monogenean. Specimens of Udonella myliobati parasitizing the copepod Lepeophtheirus natalensis, an ectoparasite of the spotted ragged-tooth shark, (Carcharias taurus), were collected and studied. A total of 771 monogenean specimens were recovered from 54 infected copepods examined, with a mean intensity of 14,3 worms per copepod. Most of the monogeneans were found attached to the dorsal surface of the lateral and frontal marginal membranes of the copepod carapace. Eggs, with filaments and adhesive discs, were found ventrally on the host, mainly attached to the maxillae and maxillipeds, in clusters of 12-14. Observations on the morphology, distribution and behaviour of this monogenean are presented with the aid of light and scanning electron microscopy. 相似文献
874.
Sixteen lambs exhibiting hepatogenous photosensitization (alveld) after grazing pasture containing Narthecium ossifragum and seven nonphotosensitized lambs grazing the same pastures were studied. All the alveld-affected lambs revealed liver damage dominated by single cell necrosis, portal fibroplasia and bile duct proliferation. Crystalloid clefts were demonstrated in the bile ducts of two and in the hepatocytes and Kupffer cells of nine photosensitized lambs. Plasma bilirubin concentration was severely increased in ten of the cases of alveld whereas the activity of aspartate aminotransferase was moderately to severely increased in seven cases. The activity of glutamate dehydrogenase was moderately elevated in one of the photosensitized lambs. The main histopathological findings in the kidneys from the alveld-affected lambs were dilated tubules, often with eosinophilic material in the tubular lumina. Regenerative changes were seen in a large proportion of the renal sections. Elevated plasma concentrations of urea and creatinine, and the renal histopathological changes, suggested that the photosensitized lambs had been through a phase of renal injury. Analysis of the free and conjugated sapogenin content in liver tissue and bile was performed by gas chromatography–mass spectrometry. There were significantly higher concentrations of conjugated episapogenins in both the liver and bile in the alveld-affected lambs than in the nonphotosensitized lambs. 相似文献
875.
A collapse of melon plants (Cucumis melo L.) grown under both winter and summer conditions in Israel was shown to be incited by the soilborne pathogenMacrophomina phaseolina (Tassi) Goid. Although symptoms were noted in the crown area of the plant, results of root isolations confirmed that the damage encountered under local conditions was due primarily to a root rot caused by this pathogen. We found infection to be more prevalent in summer than in winter sowings, and collapse in the summer occurred sooner in later than in earlier sowings. Methyl bromide fumigation controlled the pathogen, prevented collapse, and increased yield as compared with the control treatment. 相似文献
876.
By using pyrolysis-gas chromatography-mass spectrometry-based methodologies, nonvolatile oxidation products of isotopically labeled glucose/glycine model systems were studied through a postpyrolytic in situ derivatization technique by using trimethylsilyldiethylamine. Analysis of the data indicated that the known reactive sugar intermediates such as glucosone and its deoxy derivatives can undergo in Maillard model systems three types of transformations: oxidation of the aldehydic groups into carboxylic acids, oxidative cleavage of alpha-dicarbonyl moieties into aldonic acids, and benzylic acid rearrangement of 1-deoxy-glucosone into saccharinic acids. The aldonic and saccharinic acids were identified through silylation of their lactone derivatives, and their origin was verified through (13)C-labeling studies. The following lactones were identified in glucose and glucose/glycine model systems: trans-dihydro-3,4-bis[(trimethylsilyl)oxy]-2(3 H)-furanone, cis-dihydro-3,4-bis[(trimethylsilyl)oxy]-2(3H)-furanone, 2-C-methyl-2,3,5-tris-O-(trimethylsilyl)-D-ribonic acid gamma-lactone, 3-deoxy-2,5,6-tris-O-(trimethylsilyl)-D-ribo-hexonic acid gamma-lactone, 2-deoxy-3,5-bis-O-(trimethylsilyl)-pentonic acid gamma-lactone, and 2,3,5-tris-O-(trimethylsilyl)-D-arabinonic acid gamma-lactone. The observed reduction in color and aroma in Maillard reactions performed under oxidative conditions may be attributed to the oxidation of reactive dicarbonyls into the corresponding carboxylic acids or their corresponding lactones. 相似文献
877.
沙漠化对内蒙地区水热通量及降水影响的数值研究 总被引:2,自引:0,他引:2
RAMS模式被应用于内蒙干旱地区气系统水热通量交换及水循环过程研究。本文通过敏感性试验,模拟了在半沙漠化和土壤含量变化的情况下内蒙地区地气通量交换的变化及其对降水的影响。 相似文献
878.
Endocarditis caused by Corynebacterium sp in a dog 总被引:1,自引:0,他引:1
R A Henik T A Allen R L Jones W E Wingfield J Boon 《Journal of the American Veterinary Medical Association》1986,189(11):1458-1461
Mitral valve bacterial endocarditis, caused by Corynebacterium sp, was diagnosed in a dog. The bacteria had characteristics unlike those commonly recognized for most species of Corynebacterium. The primary source of bacteremia was suspected to be a pilonidal cyst of the sacrum. The dog was treated with a first-generation cephalosporin for 6 weeks, and the pilonidal cyst was surgically removed. Physical examination 1 year after initial examination revealed no abnormalities other than a cardiac murmur. On echocardiographic examination 1 year after treatment, the vegetative lesion was still present; however, chamber dimensions had returned to normal. Wall thickness and contractility remained increased. 相似文献
879.
Adhesion of Staphylococcus aureus and Escherichia coli to bovine udder epithelial cells 总被引:1,自引:0,他引:1
An assay for the adhesion of tritiated thymidine-labelled Staphylococcus aureus and Escherichia coli to bovine mammary ductular epithelial cell lines was developed. The relative adhesion of 15 strains of S. aureus to these cell lines was examined. Four strains did not adhere and the remaining 11 adhered at variable levels. Adhesion to different cell lines was generally similar. Adhesion to freshly collected bovine mammary epithelial cells was significantly greater than that to cells maintained in tissue culture. The system described was demonstrated to be a suitable model for studying adhesion of mastitis-causing organisms to bovine mammary epithelial cells. 相似文献
880.
1. An investigation was carried out into the effects of dietary α-tocopherol (α-T) concentration and source of supplemental oil on performance, activity of anti-oxidative enzymes and some immune responses in broilers from day-old to 41 d of age. 2. Three dietary concentrations of α-T (10, 50 and 100 mg/kg) with three sources of supplemental oil (sunflower - SFO, palm - PMO and safflower - SAO) were provided using a 3 × 3 experimental design. 3. Body weight gain and food conversion efficiency were not affected by either interaction or concentrations of α-T and sources of oil in diet. 4. Concentrations of total protein, globulin, triglycerides and cholesterol in sera increased significantly with dietary α-T concentration irrespective of the source of oil. Significantly higher concentration of serum albumin was evident in broilers fed on the SFO-based diet and the concentration of globulin was higher in groups fed on those diets containing PMO and SAO. 5. The lipid peroxidation (LP), measured as MDA release, decreased with the concentration of α-T in a dose-related manner with SFO- and SAO-based diets, although not with the PMO-based diet. With different oil sources, LP was significantly lower with the PMO-based diet compared to the others. Activities of glutathione peroxidase and RBC catalase increased and heterophil: lymphocyte ratio was reduced with concentration of α-T for each source of oil tested. 6. Assays for humoral and cell-mediated immune responses indicated no effect of the source of dietary supplemental oil or interaction, although an increasing concentration of dietary α-T improved cell-mediated immune responses. 7. It is concluded that sunflower oil, palm oil and safflower oil can be used as sources of oil for broiler diets without having any effect on performance, immune responses or the activity of anti-oxidizing enzymes. Higher concentrations of dietary α-tocopherol (50 or 100 mg/kg) reduced lipid peroxidation activity and enhanced activities of anti-oxidative enzymes, they also improved the cell-mediated immune responses in commercial broilers. 相似文献