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161.
A two-year-old, intact female Sussex spaniel was presented with signs of exercise intolerance. Pre- and post-exercise serum lactate and pyruvate concentrations and urinary organic acid screening supported a diagnosis of pyruvate dehydrogenase deficiency, as previously reported in this breed. Dietary therapy was initiated for six months, during which time there was no reported clinical deterioration. A full neurological examination and repeat evaluation of lactate and pyruvate concentrations before and after exercise was conducted one year after diagnosis, at which time the patient had been without dietary modification for six months and had developed more severe exercise intolerance along with evidence of central nervous system dysfunction.  相似文献   
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163.
When the first BSE case in Switzerland became public in 1990, it precipitated a chain of events with many diverse consequences. During this time, we continued to gain knowledge, implement new measures, and make practical recommendations in order to attempt to control the disease. This was made possible by the establishment of a huge data base containing information on all cases of BSE that had been diagnosed in Switzerland, as well as by the use of information from experiences in other countries. Analysis of these data allowed the sequence of events to be described temporally and spatially and an epidemiological evaluation to be made. These data also allow predictions to be made regarding the future of BSE in Switzerland, although these predictions must be interpreted cautiously.  相似文献   
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165.
Beech leaves were sampled at the end of a prolonged hot dry period at a tree decline site in the Black Forest, Germany to investigate the potential role of flavanols in defense mechanisms against environmental stress. Green and yellowing leaves were harvested from the uppermost canopy of trees that were more than 200 years old and 30 m high. Yellowing leaves had a 7.4-fold higher concentration of total flavanols than green leaves. Green leaves contained flavanol inclusions, but during yellowing the inclusions disintegrated and the cells became filled with flavanols. Abscisic acid (ABA) stimulated the release of flavanols from intravacuolar inclusions of leaf petioles and flower pedicels. In addition, ABA caused flavanols to leach from the trichomes of beech galls. The antioxidative potential of leaf extracts, as estimated by indoleacetic acid (IAA) oxidation, was significantly higher in yellowing leaves than in green leaves. In vitro experiments revealed that (+)-catechin promoted growth of beech tissue.  相似文献   
166.
ABSTRACT We have developed conditions which promote the dimorphic transition of haploid cells of Ustilago maydis in vitro by controlling the pH of the media. At low pH (below 5.0) mycelial growth occurs, whereas at neutral pH yeastlike growth takes place. We screened for mutants unable to form mycelium at low pH and obtained 26 mutants. These mutants have been characterized by their cell and colony morphology in different media. Mutations in 18 strains were found to be recessive when these strains were crossed with the wild type. Other crosses indicated that they were affected in genes other than a and b. Crosses between mutants suggest that the mutations fall in at least two complementation groups. In addition, mutants were characterized by their pathogenicity to corn seedlings. Mutations which were recessive for pathogenicity were also recessive for morphogenesis in vitro.  相似文献   
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168.
An intermediate-technology pattern matching model and decision support system for veterinary diagnosis is described. Six diseases of cattle occurring in the tropics are used to illustrate the model. The pattern matching model is composed of a series of transparent overlays and a template. Each transparent overlay represents a sign state and contains sign frequency information for the diseases on the template. By superimposing multiple transparent overlays upon the disease template, a ranked list of differential diagnoses can be obtained. Ranking is by summation of disease sign frequencies. Modifications to accommodate observational uncertainty are presented. Disease prevalences can be represented in the model.  相似文献   
169.
The PCR products of ryr1 gene amplified from genomic DNA of Sus scrofa and synthetic prolific lines of Ovis aries were analysed. The polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP), and sequencing analysis for research on ovine, ryanodine receptor ( ryr1 ) gene. The ovine fragment of ryr1 gene did not differ from exon 17 of the porcine ryr1 gene.  相似文献   
170.
Although uncommon to rare in occurrence, cutaneous vasculitides and vasculopathies are becoming better recognized entities in veterinary medicine. The heterogeneity in their clinical presentations can be confusing, and the diagnostic evaluation of suspected cases can be clinically and financially challenging. The most important step is confirming a vasculitic/vasculopathic process histologically and then searching for an underlying cause. As many cases are diagnosed as idiopathic by exclusion, a familiarity with treatment options is important and may be guided in some cases by the histological inflammatory pattern. Because of the frequent temporal association with drug administration, any case of vasculitis requires a thorough drug history and physical examination for systemic complications. Familiarity with breed-associated vasculopathies is also key in properly diagnosing and managing these problems.  相似文献   
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