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991.
992.
A pregnant quarterhorse mare became acutely lame as a result of severe swelling of its right hind leg, thought to have been caused by a fracture or a muscle tear. Diagnostic procedures ruled out a traumatic musculoskeletal cause and a physical examination revealed chronic pastern dermatitis ('scratches'/'grease heel'). Histopathological evaluation of biopsy samples from the right hind leg was consistent with a leucocytoclastic vasculitis, and culture yielded Staphylococcus intermedius. The treatment and infectious causes of pastern dermatitis are discussed.  相似文献   
993.
Reasons for performing study: Mesenchymal stromal cells (MSCs) represent an attractive source for regenerative medicine. However, prior to their application, fundamental questions regarding molecular characterisation, growth and differentiation of MSCs must be resolved. Objectives: To compare and better understand the behaviour of equine MSCs obtained from bone marrow (BM) and adipose tissue (AT) in culture. Methods: Five horses were included in this study. Proliferation rate was measured using MTT assay and cell viability; apoptosis, necrosis and late apoptosis and necrosis were evaluated by flow cytometry. The mRNA expression levels of 7 surface marker genes were quantified using RT‐qPCR and CD90 was also analysed by flow cytometry. Differentiation was evaluated using specific staining, measurement of alkaline phosphatase activity and analysis of the mRNA expression. Results: High interindividual differences were observed in proliferation in both cell types, particularly during the final days. Statistically significant differences in viability and early apoptosis of cultured AT‐ and BM‐MSCs were found. The highest values of early apoptosis were observed during the first days of culture, while the highest percentage of necrosis and late apoptosis and lowest viability was observed in the last days. Surface marker expression pattern observed is in accordance to other studies in horse and other species. Osteogenic differentiation was evident after 7 days, with an increasing of ALP activity and mRNA expression of osteogenic markers. Adipogenic differentiation was achieved in BM‐MSCs from 2 donors with one of the 16 media tested. Chondrogenic differentiation was also observed. Conclusions: Proliferation ability is different in AT‐MSCs and BM‐MSCs. Differences in viability and early apoptosis were observed between both sources and CD34 was only found in AT‐MSCs. Differences in their osteogenic and adipogenic potential were detected by staining and quantification of specific tissue markers. Potential relevance: To provide data to better understand AT‐MSCs and BM‐MSCs behaviour in vitro.  相似文献   
994.
In everyday life, the successful monitoring of behavior requires continuous updating of the effectiveness of motor acts; one crucial step is becoming aware of the movements one is performing. We studied the anatomical distribution of lesions in right-brain-damaged hemiplegic patients, who obstinately denied their motor impairment, claiming that they could move their paralyzed limbs. Denial was associated with lesions in areas related to the programming of motor acts, particularly Brodmann's premotor areas 6 and 44, motor area 4, and the somatosensory cortex. This association suggests that monitoring systems may be implemented within the same cortical network that is responsible for the primary function that has to be monitored.  相似文献   
995.
An autumn bloom of sea-ice algae was observed from February to June of 1992 within the upper 0.4 meter of multiyear ice in the Western Weddell Sea, Antarctica. The bloom was reliant on the freezing of porous areas within the ice that initiated a vertical exchange of nutrient-depleted brine with nutrient-rich seawater. This replenishment of nutrients to the algal community allowed the net production of 1760 milligrams of carbon and 200 milligrams of nitrogen per square meter of ice. The location of this autumn bloom is unlike that of spring blooms previously observed in both polar regions.  相似文献   
996.
This report describes the clinical course and surgical findings of a 5-year-old Warmblood gelding referred for colic with a previous history of intermittent colic episodes, and gastric ulcers diagnosed by gastroscopy in the preceding months. The horse underwent medical treatment but remained painful and surgery was elected. The horse underwent an exploratory laparotomy during which an impaction was identified in the transverse colon that was associated with an approximately 1 metre segment of nasogastric tube. The foreign body was removed via an enterotomy in the left dorsal colon, and the horse recovered well from surgery. No complications were encountered post-operatively.  相似文献   
997.
998.
The motivation for this work was to investigate the possibility of accurately determining the age of a tern chick using easily obtained body measurements. We describe the construction of a nonlinear multivariate hierarchical model for chick growth and show how it can be estimated using Markov chain Monte Carlo techniques. A simple extension of the analysis allows for estimation of the ages of unknown chicks. Posterior distributions of the unknown ages are derived, so that the accuracy of age determination can be examined. We further extend our model and analysis to include the possibility that chicks fall into distinct groups with different growth characteristics. The technique is illustrated using data on the weight and wing length of black-fronted terns from the Ohau River, New Zealand. It is found that dating to within one day is possible, but only in some areas of the data space. The concept of “braiding” of multivariate growth curves is introduced to explain the varying accuracy of age determination.  相似文献   
999.
Sera from 300 dogs from Ghent and Antwerp were tested for antibodies to Neospora caninurn using an Indirect fluorescent antibody test. Overall, 11 per cent (995 to 13 per cent; confidence interval of 95 per cent) of dogs were seropositive, at titres of 1:50 to 1:800. No sex or breed differences were detected, but there was an Increase In seropositivity with age.  相似文献   
1000.
ABSTRACT A streptomycin- and rifampicin-resistant mutant of Xanthomonas al-bilineans was used to study symptom expression of leaf scald disease (LSD) and colonization of sugarcane (Saccharum spp.) and its wild relatives by this bacterial pathogen. A total of 40 sugarcane cultivars and 15 clones from the Saccharum complex that differed in resistance to LSD were inoculated by a decapitation technique in both field and greenhouse experiments. In the plant crop, disease severity varied between 0 for the most resistant genotypes and 100 for the most susceptible ones. Resistance to LSD was characterized by limited colonization of the host plant by X. albilineans. Although almost all genotypes were colonized by the pathogen, the greatest bacterial population densities were found in the susceptible cultivars. There was a high correlation between disease severity and pathogen population in the apex. Several genotypes exhibited no or slight symptoms even though they were highly colonized in the upper and/or basal nodes of stalks. Two mechanisms, therefore, may play an important role in resistance to LSD: resistance to colonization of the apex, which is characterized by absence of symptoms, and resistance to colonization of the upper and lower parts of the stalk. In contrast, disease severity and pathogen population densities in the first ratoon crop in the field were nil or very low in the stalks, except for the highly susceptible cv. CP68-1026. Sugarcane ratoons, therefore, may recover from the disease after plant cane infection. Nevertheless, because low levels of the pathogen were still detected in some stalks, it is possible that LSD could develop from latent infections if favorable environmental conditions occur.  相似文献   
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