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921.
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Using databases     
Through a relatively simple computer technique known as online searching, practitioners can use computers to "reach out" beyond their practice walls to expand their knowledge base. By bringing information sources closer to veterinarians, feelings of isolation, frustration, and ineptitude can be replaced with feelings of certainty, confidence, and knowledge. This article explores the equipment and the software needed, and by giving examples of a few of the veterinary databases, illustrates some techniques employed in signing up and signing on to the power of online searching.  相似文献   
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A ram lamb with congenital goitre showed signs of respiratory distress at birth. All previously affected lambs from this flock bad been born dead or bad died soon after birth. The serum free-thyroxine level at 1 birth was low (9.8 pmol/l) but treatment with oral L-thyroxine resulted in an increase in thyroxine blood levels to above normal and regression of the goitre. Four weeks after withdrawal of thyroid supplementation and when the lamb was eight weeks old, the radio iodide uptake mechanism of the thyroid glands was shown to be intact but the iodide was not organified. Low normal peroxidase activity was demonstrated in fresh thyroid tissue but gel electrophoresis demonstrated an absence of normal thyroglobulin from extracts of the goitrous thyroid. This lamb and the other affected lambs of this flock have an inherited defect in thyroglobulin synthesis and it is likely that the respiratory distress was associated with the low levels of thyroid hormone affecting foetal lung development.  相似文献   
928.
On a property in the Nelson District, blood and urine samples were taken from red deer (Cervus elaphus) from which low (<1:100) antibody titres to serovar copenhageni and suspected leptospiral abortions had previously been reported. A total of 27 hinds were sampled. Microscopic agglutination test (MAT) titres in sera ranging from 1:32 to 1:128 were found in six animals. Thirteen leptospiral isolations were made from nine of the 27 urine samples. Four of these were typed as copenhageni and nine as hardjo. Two cultures were prepared from each urine sample and hardjo and copenhageni were both isolated from single urine samples from two animals. None of the 27 deer had serum MAT titres at 1:32 or above to copenhageni.  相似文献   
929.
Of 32 calves given an unknown amount of a pluronic bloat mixture with their milk, 28 died in convulsions over 24 hours. Supportive therapy was unsuccessful. Concentrations of pluronic present in abomasal and rumenal contents supported a diagnosis of pluronic poisoning.  相似文献   
930.
Twelve isolates of bovine rotavirus, originating from eight dairy herds in Quebec known to have frequent epizootics of diarrhea in young calves in the last five years, were successfully propagated in cell cultures. The 12 isolates produced clear-cut plaques in BSC-1 cells and, except for one isolate, agglutinated human group "O" erythrocytes to an higher titer than bovine erythrocytes. Antisera to each isolate were produced in rabbits and used to study their antigenic relationships. All the isolates shared the group-specific immunofluorescent antigen and were antigenically related as demonstrated by the seroneutralization and hemagglutination-inhibition tests. However, the relationships to the Nebraska rotavirus was quite weak in cases of two Quebec isolates. When the genomes of the various isolates were compared by polyacrylamide gel electrophoresis, at least three different reproducible fractionation patterns could be identified.  相似文献   
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