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71.
To evaluate antigen-specific proliferative and activation-associated responses from Mycobacterium bovis-infected reindeer, blood mononuclear cells from M. bovis- (n = 10) and non-infected reindeer (n = 4) were stimulated with a recombinant early secretory antigenic target-6 and culture filtrate protein-10 fusion protein (rESAT6:CFP10), M. bovis purified protein derivative, pokeweed mitogen, or medium alone and evaluated by flow cytometry using dye tracker analysis and cell surface marker staining. gammadelta TCR+ and CD8+ cells, but not CD4+ cells, from M. bovis-infected reindeer proliferated in response to specific antigen stimulation. Expression (i.e., mean fluorescence intensity) of CD44 was increased and CD62L decreased on proliferative as compared to non-proliferative fractions in antigen- and mitogen-stimulated cultures. In response rESAT6:CFP10 stimulation, MHC II fluorescence intensity was increased on CD4+, gammadelta TCR+, CD172a+, and IgM+ cells from infected reindeer as compared to that of non-stimulated cells from the same reindeer. Recombinant ESAT6:CFP10 stimulation also induced expansion of a CD172a+, MHC II+ population within mononuclear cell cultures from M. bovis-infected reindeer. Despite a moderate challenge dose and extended duration of incubation, experimental infection of reindeer was generally limited to lymph nodes draining the inoculation site, suggestive of host resistance to progressive disease. Present in vitro findings, therefore, may be predictive of host responses by reindeer that limit progression to disseminated disease.  相似文献   
72.
A condition characterised by the early onset of vestibular deficit and hearing loss was investigated in the dobermann breed of dog. Affected pups showed behavioural signs of head tilt, circling and ataxia and there was a total absence of vestibular response to rotation or caloric stimulation. Severe deafness, as assessed by brainstem auditory evoked response testing, was present by three weeks of age in all affected animals. The inner ears showed a progressive neuroepithelial type of cochlear degeneration with loss of the auditory sensory cells. In the vestibular system, however, there was no equivalent sensory cell loss and the only abnormal feature was the absence or abnormality of the otoconia in some of the affected animals. Pedigree analysis suggested that the condition was inherited as an autosomal recessive trait.  相似文献   
73.
[14C]ring-Bromoxynil octanoate was applied to the leaves of wheat seedlings, which were cultivated in a growth cabinet under controlled conditions for 14 days. Fractionation of the metabolites present in the treated leaves, which accounted for about 63% of the radioactivity applied, indicated a complex metabolic pathway resulting from initial hydrolysis to free bromoxynil, followed by three consecutive or concurrent steps (a) hydrolysis of the cyano group to the amide and carboxylic acid, followed by decarboxylation to 2,6-dibromophenol (0.5% of the 14C applied), (b) replacement of one or both bromine atoms by hydroxy groups to 3-bromo-4,5-dihydroxybenzonitrile (1.3 %) and 3,4,5-trihydroxybenzo-nitrile (0.6 %) or their hydrolysis products, (c) replacement of one or both bromine atoms by hydrogen, giving 3-bromo-4-hydroxybenzonitrile (1.9 %) and 4-hydroxy-benzonitrile (0.6%) or their hydrolysis products. Some of the phenolic acids or phenols formed are natural plant constituents. The metabolites identified represented in all about 11 % of the herbicide applied, but no individual metabolite accounted for more than a small proportion of it.  相似文献   
74.
The introduction of mechanised harvesting often results in a redesign of the crop canopy. Computer models have been used to predict light interception, and hence potential yield, by a range of hedgerow tree forms and spacings as a guide to the design of orchard systems for mechanical harvesting. Light interception is increased by increasing tree height, thickness and leaf-area density, and by reducing the clear alleyway. Narrow hedgerows less than 2 m high will need straddle harvesting to avoid loss of light interception and yield.  相似文献   
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The prevalence of antibody titres to a range of 20 leptospira antigens in the serum of horses and ponies with no ophthalmic abnormalities and with ophthalmoscopic evidence of endogenous uveal inflammatory disease was determined using a microscopic agglutination technique. Titres against leptospira antigens were observed in 13 out of 138 (9.1 per cent) animals with no ophthalmic abnormalities, and in three out of 27 (11.1 per cent) animals with anterior uveitis. Serovar sejroe was common to all seropositive animals with anterior uveitis. The results show that leptospira infection is not a major factor in the aetiology of equine anterior uveitis in the UK, but suggests that the organism may be associated with some cases of recurrent anterior uveitis.  相似文献   
78.
A preliminary investigation of the blood levels of carbenicillin, after the administration of a single intramuscular injection, suggests that the tortoise's bladder may act as a reservoir of antibiotic that is available for resorption. This phenomenon could confound the establishment of a safe, effective dose regime for antibiotics, in tortoises, which are excreted in an unchanged active form in urine.  相似文献   
79.
The concentrations of several post mortem aqueous humour chemical constituents were compared with ante mortem serum chemical values in the horse. Urea nitrogen and creatinine values in post mortem aqueous humour were good predictors of ante mortem serum values. Aqueous humour urea nitrogen increased only slightly and creatinine did not change significantly for up to 24 h after death. Formulae were derived for calculating estimated ante mortem serum urea nitrogen and creatinine from aqueous humour values obtained after death. These results from normal horses identify analytes that are accurate predictors of ante mortem serum values. Determination of post mortem aqueous humour urea nitrogen of creatinine may assist in interpretation of the functional significance of equivocal histological lesions in the kidney.  相似文献   
80.
The ceroid-lipofuscinoses are a group of inherited neurodegenerative diseases of humans and animals characterised by the accumulation of a fluorescent lipopigment in neurons and other cells within the body. Syndromes occurring in dogs are classified, on the basis of the age of onset and, to a lesser degree, the course of the disease, as prepubertal-protracted, early adult acute and adult onset. Clinical signs are generally those of progressive loss of vision, motor disturbances such as ataxia, tremors, seizures and proprioceptive deficits together with behavioural changes including loss of learned behaviour, fearfulness and aggression. The various syndromes can be expected to reflect different mutations, at least some of which affect the catabolism of subunit c of mitochondrial adenosine triphosphate (ATP) synthase. Confirmation of diagnosis depends on the demonstration of lipopigment in brain or skin biopsies by histochemistry, fluorescence or electron microscopy.  相似文献   
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