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1.
Polarised light biomicroscopy was used to examine the normal pre-corneal tear film in 21 eyes of 12 pekingese dogs. The purpose of the study was to examine the influence of excessive exophthalmos on the pre-corneal tear film in the dog. The majority of the animals were found to have high levels of ocular surface contamination by particulate material and plaques of viscous mucus. Other abnormalities included surface lipid with an abnormal granular (three dogs) or 'curdled' (two dogs) appearance; excessive thinning of the lipid layer of the tear film; and the presence of dark globular structures in two dogs, which were presumed to be abnormal meibomian lipid. Break up of the tear film was observed in one dog. Grossly, a thread of viscous mucus was frequently observed along the margin of the lower eyelid. It is postulated that this thread forms because of the excessively exophthalmic conformation of the breed, which prevents the normal access of effete mucus and entrapped debris to the lower conjunctival fornix. The combination of the above factors in the pekingese is suggested as the mechanism whereby the tear film has a reduced stability, thus enhancing the risk from factors more usually considered to initiate corneal ulceration in the breed. The possible adverse effects of lid splitting for the mass removal of distichiae in exophthalmic dogs is discussed. 相似文献
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Pearson GR Bazeley KJ Jones JR Gunning RF Green MJ Cookson A Woodward MJ 《The Veterinary record》1999,145(13):370-373
Escherichia coli O26:K60, with genetic attributes consistent with a potentially human enterohaemorrhagic E. coli was isolated from the faeces of an eight-month-old heifer with dysentery. Attaching and effacing lesions were identified in the colon of a similarly affected heifer examined postmortem, and shown to be associated with E. coli O26 by specific immunolabelling. 相似文献
5.
SUMMARY Clinical signs of proliferative haemorrhagic enteropathy (PHE) including anaemia, dysentery and sudden death were observed in finisher pigs and young breeding stock on 2 farms. On farm A, PHE occurred 12 months after repopulation of the farm. Other outbreaks of PHE occurred after the withdrawal of therapeutic concentrations of in-feed antibacterial agents (farm A), or after monensin sodium (100 g/t) replaced olaquindox (100 g/t) in feed (farm B). The outbreaks, the possible sources of contamination and the role of antibacterial feed additives in the treatment and control of PHE are described. 相似文献
6.
I. Demirkan S. D. Carter R. D. Murray R. W. Blowey M. J. Woodward 《Veterinary microbiology》1998,60(2-4):285-292
A study was carried out to determine whether spirochaetes are frequently associated with digital dermatitis in United Kingdom (UK) dairy cattle. Histopathological examination of lesions using a silver stain showed a large number of unidentified spirochaete-like organisms present in digital dermatitis hoof skin tissue in all examined biopsies. Immunocytochemical staining demonstrated that spirochaetes in skin lesions were identified by polyclonal antisera to Borrelia burgdorferi, Treponema denticola and Treponema vincentii (again all biopsies were positively stained), whereas monoclonal antibodies to B. burgdorferi and any Treponema pallidum did not stain any organisms in all biopsies. A PCR of 16S rRNA, previously shown to be specific for a new treponeme, was employed and produced positive results from 82.4% of digital dermatitis tissues. It is concluded that this spirochaete (or related spirochaetes), which is similar to human oral treponemes, is frequently associated with, and may be responsible for, pathological changes in digital dermatitis. 相似文献
7.
B B Woodward G P Heffelfinger D I Ruggles 《Journal of the Association of Official Analytical Chemists》1979,62(5):1011-1019
A collaborative study for the determination of sodium saccharin, sodium benzoate, and caffeine in 3 types of soda beverage, cola, grape, and lemon-lime, has been completed using reverse phase high pressure liquid chromatography with a muC18 column and acetic acid mobile phase. Recoveries for sodium saccharin were 98.6, 98.0, and 99.1%; for sodium benzoate, 100.6, 102.6, and 100.6%; and for caffeine, 100.8, 101.4, and 101.1%, respectively. The method has been adopted as official first action. 相似文献
8.
Woodward AS 《Science (New York, N.Y.)》1909,30(767):321-331
9.
G H Snoeyenbos O M Weinack A S Soerjadi-Liem B M Miller D E Woodward C R Weston 《Avian diseases》1985,29(4):1004-1011
Competitive exclusion of salmonella by native gut microflora was studied in 24 groups of 100 chickens each started in thoroughly cleaned and sanitized isolation facilities. During 53-day test periods, infection by both Salmonella infantis and S. typhimurium was greatly restricted in groups previously treated with native microflora compared with control groups. Feed and water starvation for 48 hours starting at either 23 or 51 days did not affect the incidence of infection in protected groups. The protective flora spread readily to adjacent untreated groups; infected groups given the protective flora at 11 days exhibited a more rapid elimination of infection than untreated control groups. 相似文献
10.
Woodward AS 《Science (New York, N.Y.)》1935,82(2131):399-407