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1.
A previously undocumented hypokalaemic condition with a cyclical nature, comprising acute bouts of polymyopathy followed by spontaneous recoveries, is described in the cat. Cats being fed a high protein vegetarian diet developed recurrent episodes of polymyopathy, characterised by ventroflexion of the head and neck, stiff forelimb gait, lateral head-resting and generalised muscle weakness. Plasma potassium concentrations (mean +/- standard deviation) were reduced from 3.28 +/- 0.33 mmol/l at the beginning of the experiment to 2.45 +/- 0.24 mmol/l during bouts of myopathy. This hypokalaemia was associated with increased creatine kinase activities indicative of muscle damage, and decreased urinary potassium concentrations, and was caused by insufficient dietary potassium. Cats that received the same diet supplemented with potassium did not develop hypokalaemic polymyopathy. Spontaneous recoveries of affected cats were not associated consistently with increases in plasma potassium concentrations. Plasma taurine concentrations decreased and glutamic acid increased markedly in all cats fed the experimental diet. There was no evidence of thiamin deficiency associated with the high glutamic acid intake. Veterinarians should be aware that hypokalaemic cats, and in particular those on potassium-deficient diets, may show cyclical disease with episodes of polymyopathy recurring after periods of spontaneous clinical recovery. This condition in cats may be a useful animal model for familial hypokalaemic periodic paralysis in humans.  相似文献   
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This study describes the experience with hypofractionated radiation therapy of squamous cell carcinoma and melanoma in dogs and cats. A total dose of 32-48 Gray (Gy) was delivered once a week in 8 Gy fractions. 34 animals in which a complete surgical excision was impossible were treated. There was no tumor detectable macroscopically in 14 patients at the beginning of radiation therapy. In 20 animals the median volume of the tumor was 9.9 cm3. The median survival times and the local tumor control of squamous cell carcinoma of the oral and nasal cavities and of the body are comparable to results which were reached with a Monday-Wednesday-Friday scheme. For the treatment of Melanoma the hypofractionated radiation therapy is first choice. There are no significant side effects. Late side effects did not occur. 88% of the owners are satisfied with this kind of treatment and would choose it again.  相似文献   
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Research on the pathogen Listeria monocytogenes is a key issue both for the clinical and the food microbiologist owing to the unique pathway of infection and the exposure of humans via contaminated foods. Although, in Austria, the incidence of listeriosis is about 870-fold lower than the incidence for Salmonella infection, the food law manages both foodborne pathogens with a comparable stringency. The current risk management is based on the assumption that environmental L. monocytogenes isolates, from which the pool of "foodborne" isolates is recruited, are of similar pathogenicity compared to clinical and outbreak isolates. This verdict became doubted in the recent years. Characterization of L. monocytogenes by virulence gene sequencing, virulence studies in vivo and in vitro and by molecular typing was considerably stimulating the discussion on virulence variability in L. monocytogenes. This article provides insights in the value of epidemiological follow-up studies by presenting a typing study on 15 cases of listeriosis observed in a district hospital in Turkey. Furthermore results from typing L. monocytogenes either by virulence gene sequencing, mismatch amplification mutation assay or by pulsed field gel electrophoresis are discussed. The close interaction of molecular microbiology with food microbiology both in applied and basic science is currently creating a new discipline of molecular food microbiology. We are convinced that veterinary medicine will contribute to this exiting development in a fruitful way.  相似文献   
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Rabbit-fish, Siganus oramin, reared in a closed seawater system on an artificial diet, were brought to maturity and spawned artifically after human chorionic gonadotropin (HCG) injections. Eggs were incubated under different salinity regimes. Hatching success between 20.9 and 32.2‰ S was ≥95%.  相似文献   
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To preserve populations of endangered bee species, sound knowledge of their maximum foraging distance between nest and host plants is crucial. Previous investigations predicted maximum foraging distances of 100-200 m for small bee species and up to 1100 m for very large species based on mainly indirect methods. The present study applied a new and direct approach to experimentally investigate maximum foraging distances in solitary bees. One endangered and two common species of different body sizes, all of which restrict pollen foraging to a single plant genus, were established in a landscape lacking their specific host plants. Females were forced to collect pollen on potted host plants that were successively placed in increasing distance from fixed nesting stands. The maximum foraging distance recorded for the small Hylaeus punctulatissimus was 1100 m, for the medium sized Chelostoma rapunculi 1275 m and for the large Hoplitis adunca 1400 m, indicating that maximum foraging distances at species level have been underestimated. However, the capability to use resources on such a large spatial scale applied only to a small percentage of individuals as 50% of the females of H. punctulatissimus and H. adunca did not forage at distances longer than 100-225 m and 300 m, respectively. This finding suggests that a close neighbourhood of nesting and foraging habitat within few hundred meters is crucial to maintain populations of these species, and that threshold distances at which half of the population discontinues foraging are a more meaningful parameter for conservation practice than the species specific maximum foraging distances.  相似文献   
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Seven vaccines prepared from pathogenic strains of different origin of Leptospira interrogans [serovars icterohaemorrhagiae (one strain) and copenhageni (6 strains)] were examined in protection tests on golden hamsters. Two of the copenhageni strains were used for challenge. The organs (kidneys, spleen, liver) in the vaccinated animals surviving challenge were protected to a varying degree. Low rates of survival were associated with a high incidence of Leptospira-positive findings, partly connected with focal lesions of the kidneys. On the other hand, in the groups in which all the animals survived, it was not possible to culture leptospires from their organs or to detect leptospiral antigen in these organs by immunohistochemical investigation. A protection of the organs that prevents vaccinated animals from shedding leptospires after infection clearly depends on the vaccine dose administered and the efficacy of the vaccine which can be measured in potency tests based on the survival rate as the relevant parameter.  相似文献   
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In dogs, secondary polycythemia (SP) may be associated with polyuria and polydipsia (PU/PD). The pathogenesis of this PU/PD has not yet been explained. We hypothesized that hyperviscosity and increased blood volume in SP might affect vasopressin (VP) release, resulting in PU/PD. This hypothesis was tested in 2 dogs with SP caused by renal neo-plasia and PU/PD. Osmoregulation of VP release was studied by a modified water deprivation test and by investigating the VP response to hypertonic saline infusion.
Water deprivation test results were consistent with an inability to produce concentrated urine despite increasing plasma osmolality. During hypertonic saline infusion, the osmotic threshold of VP release was markedly increased in both dogs, resulting in a delayed VP response to increasing plasma osmolality. The sensitivity of VP release was low normal in both dogs. We conclude that blood hyperviscosity and increased blood volume led to impaired VP release and polyuria.  相似文献   
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