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71.
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Paraffin blocks and mineral oil were used as a model to determine the effect of dependency versus nondependency on radiographic visualization of lung lesions in lateral thoracic radiographs. It was concluded that the increased opacity of the material surrounding the lesion, not contact between the heart and the lesion, was responsible for the inability to detect lung disease in the dependent lung. The results were tested in dogs with pneumonia in the right middle lung lobe. When the dog was in right lateral recumbency, the dependent right lung was increased in opacity and decreased in volume and the pulmonary lesion was difficult to detect. When the dog was in left lateral recumbency, the nondependent right lung was increased in volume and decreased in opacity and the pulmonary disease was clearly visible. A single recumbent lateral radiograph must not be used to assess a dog with suspected lung disease because lesions in the dependent lung lobes may not be detected.  相似文献   
73.
Pharmacokinetics of sulfamethazine in male, female and castrated male swine   总被引:1,自引:0,他引:1  
The concentration of sulfamethazine in plasma and sulfamethazine and its metabolites in urine were compared in male, female and castrated male swine. A surgical technique for placement of catheters in the urinary bladder was used to facilitate the collection of urine in males and castrated males. The elimination rate of sulfamethazine from plasma and the excretion of parent drug and metabolites into urine did not differ significantly among females, males and castrated male swine.  相似文献   
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SUMMARY Mean concentration of cadmium (Cd) in kidneys of hogget sheep from 67 flocks grazing in the Agricultural Region of Western Australia was tested for association with soil, pastoral, climatic and nutritional factors. Hoggets grazing pastures on acidic soils and soils with a sandy-textured surface had higher Cd concentrations in kidneys than hoggets grazing pastures on more alkaline soils or soils with a clay-textured surface. Application of more than 100 kg of phosphatic fertiliser during the past 3 years to loamy soils was also associated with greater Cd concentration in kidneys of the grazing animals.  相似文献   
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Geminiviruses are plant viruses that infect a broad range of crops and cause extensive losses worldwide, having an important economic impact. C2, a multifunctional pathogenicity factor encoded by geminiviruses, has been recently shown to suppress the responses to jasmonates in the host plant, which might at least partially explain its well-established role in pathogenicity. Sulphur is one of the essential macro-elements for plant life, and is considered to have a role in plant defence, in a phenomenon named sulphur-induced resistance (SIR) or sulphur-enhanced defence (SED). In this work, we show that geminivirus C2 protein represses the expression of genes involved in the sulphur assimilation pathway in Arabidopsis, but, interestingly, this effect can be neutralized by exogenous jasmonate treatment. These preliminary results may raise the idea that geminiviruses might be affecting sulphur metabolism, and maybe counteracting SIR/SED, through the manipulation of the jasmonate signalling pathway, which would define a novel strategy in plant-virus interactions and may unveil SIR/SED as an important player in the plant defence against viruses.  相似文献   
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The intradermal tuberculin tests and the interferon-gamma (IFN-γ) assay are the principal tests used worldwide for the ante-mortem diagnosis of bovine tuberculosis. The conventional reagent currently in use in these tests is purified protein derivative (PPD) tuberculin obtained from Mycobacterium bovis culture. The components of PPD are poorly characterized and difficult to standardize. To overcome this issue, antigens specific to the Mycobacterium tuberculosis complex are being studied. Here we have assessed the biological potency of ESAT-6, CFP-10 and Rv-3615c presented as peptide or recombinant protein cocktails in comparison with the standard bovine PPD used routinely in Spanish eradication campaigns. The study was performed in cattle (n=23) from a herd with natural M. bovis infection. Animals were simultaneously injected with PPD and the peptide and protein cocktails. The percentages of cattle reacting positively to single intradermal test were 60.9% (bovine PPD), 47.8% (peptide cocktail) and 60.9% (protein cocktail), with no significant difference between the actual skin fold thickness increases (p>0.05). The IFN-γ assay detected 60.9% of animals when stimulation was performed with bovine PPD, but decreased to 52.2% when stimulation was performed with the peptide cocktail and to 47.8% when stimulation was performed with the protein cocktail. However, no significant differences were found between IFN-γ responder frequencies (p>0.05). These results show a potential use of these defined reagents for in vivo tuberculosis diagnosis.  相似文献   
79.
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   
80.
At the end of September 2000, clinical symptoms of Bluetongue appeared in sheep flocks of the Balearic Islands (Spain). The presence of the BTV serotype 2 in tissue and blood samples of affected animals was confirmed by laboratory techniques. A systematic vaccination were carried out in affected areas using a live monovalent serotype 2 vaccine available from Onderstepoort laboratory (South Africa). In order to perform epidemiological studies, a new method to differentiate between the NS1 genes of BTV-2 affecting the Balearic islands and that of the Onderstepoort commercial live virus vaccine (monovalent, serotype 2) has been developed. This procedure is based on the use of an RT-PCR, followed by restriction endonuclease analysis. Epidemiological data of a study carried out in the period January-October 2001 using this procedure are included.  相似文献   
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