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31.
Osteomyelitis caused by Cryptococcus neoformans was diagnosed in a three-year-old male Irish wolfhound. The case details and radiological findings of radiolucency and periosteal reaction of the left third metatarsal bone had lead to an initial diagnosis of a malignant bone tumour. Biopsy revealed a fungal granuloma and culture identified the causal organism. A four month course of ketaconazole was instigated and the lameness resolved. Twelve months after the end of treatment there was no recurrence of the problem.  相似文献   
32.
Five studies were performed to determine factors affecting progesterone concentration in skim milk. Results of the first study indicated that progesterone concentration was higher in skim milk of samples kept 16 hours in an ice bath (0 C) than of those left at room temperature (21 C). In the second study, this temperature effect was found to be reversible, with skim milk progesterone concentration increasing when whole milk samples were cooled prior to centrifugation. In the third study, [3H]-labeled progesterone was used to determine the relationship between fat content of foremilk (the first milk obtained from the teats), midmilk (milk obtained midway through milking), and strippings (milk obtained immediately after milking machines have been removed) samples and temperature (4 C and 21 C) on the percentage of progesterone in the skim milk fraction. The relationship between percentage of butterfat and percentage of progesterone in skim milk was linear when the log of these variables was used for calculations. In the fourth study, assayable progesterone in the skim milk fraction of foremilk, midmilk, and strippings was affected by temperature. In the fifth study, a multiple-regression procedure was used to determine the amount of variation in percentage of radioactive progesterone in the skim milk fraction. Independent variables (whole milk butterfat and temperature of incubation [1, 3, 13, 22, 37, and 50 C]) and the natural log of each variable, were entered into a stepwise multiple-regression analysis.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
33.
Reference strains for Haemophilus parasuis serovars 1 to 7 were examined for virulence by inoculation of guinea pigs. Guinea pig response to intraperitoneal inoculation was similar for the 7 reference strains. However, apparent differences in virulence were detected after intratracheal inoculation. Cells of the references strains for serovars 1 and 5 were most invasive, causing moribundity or death at higher doses and a persistent septicemia at lower doses. Haemophilus parasuis could be isolated from respiratory and systemic sites; purulent bronchopneumonia, pericarditis, and pleuritis were apparent in infected guinea pigs. Inoculation of cells of the reference strains for serovars 2 and 6 also resulted in bronchopneumonia and moribundity or death in some guinea pigs; however, reisolation of H parasuis and microscopic lesions at necropsy were less pronounced than those observed with serovars 1 and 5. Inoculation of cells of serovars 3, 4 and 7 induced only transient clinical signs and minimal evidence of H parasuis infection at necropsy. The data from intratracheal inoculation of guinea pigs are similar to data from other investigations in swine, indicating differences in the pathogenic potential of H parasuis strains. Thus, guinea pigs may be useful as a laboratory animal model for examining cellular factors associated with virulence and immunogenicity of H parasuis.  相似文献   
34.
The progressive autolytic changes of atrial specific granules (ASGS) up to 24 hours after death were studied electron microscopically. Tissue samples taken from the left auricular myocardium of four pig hearts at 0, 0.5, 1.5, 3.5, 6, 12 and 24 hours post mortem were fixed for 24 hours by immersion in 2.5 per cent cacodylate buffered glutaraldehyde (pH 7.4). Two pig hearts were kept at 20 degrees C and two at 4 degrees C. Although typical autolytic changes were seen in many organelles, no remarkable modifications in aspect, distribution, content and diameter of ASGS were observed in all samples. The results of this study indicate that ASGS are not morphologically affected by the autolytic processes, at least during the first 24 hours. Hence, the electron microscopic evaluation of ASGS does not need a particular fixation method such as perfusion. This may eliminate technical problems when slaughterhouse material is used.  相似文献   
35.
Bovine spongiform encephalopathy: epidemiological features 1985 to 1990.   总被引:4,自引:0,他引:4  
Following the identification of bovine spongiform encephalopathy (BSE) in the British cattle population in 1986 epidemiological studies were launched. This paper provides an updated account of the epidemiological features of BSE from 1985, when the first cases, based on clinical histories, occurred, until 1990. The number of cases up to December 1989 represents an annual incidence of 3.9 confirmed cases per 1000 adult animals in Great Britain. Many more dairy herds were affected than beef suckler herds, a difference attributable to the difference in feeding practices between the two herd types. The geographical variation in incidence previously described has persisted with the highest incidence in the south and east of England. Other features of the epidemiology, including the low within-herd incidence, remained unaltered from the earlier findings. The results support the previously suggested hypothesis that the outbreak of BSE was due to the sudden exposure of the cattle population to a scrapie-like agent in 1981/82. There was no evidence of direct transmission between cattle during the period considered.  相似文献   
36.
Seven of 30 canaries in an aviary in New Zealand developed ophthalmic problems. Clinically, 5 birds had unilateral and 2 birds had bilateral lesions characterized by conjunctivitis, crusty exudates on eyelids, and collapse of the eyeball. Microscopic lesions in 12 of 14 eyes examined included inflammation of the choroid and retina, with osseous replacement of the globe in some. Numerous Toxoplasma gondii tachyzoites were seen in the detached retina and vitreous humor of acutely affected birds. The diagnosis of toxoplasmosis was confirmed by immunohistochemical staining with T gondii antiserum. Affected birds had encephalitis, and T gondii was localized in the brains of these by immunohistochemical examination and by use of bioassays in mice. Toxoplasmosis should be considered in differential diagnosis of ophthalmitis in canaries.  相似文献   
37.
The case records of 149 dogs examined from 1985 to 1989 with clinical signs of nasal disease were reviewed. Gross rhinoscopy was performed in 119 dogs, and rhinoscopy-assisted pinch biopsy was performed in 109. Rhinoscopy was performed by use of a 2.7-mm rigid fiberoptic endoscope. Mucosal biopsy specimens were obtained with rhinoscopic guidance by use of a 2 x 3-mm biopsy forcep. Gross, cytologic, and histologic findings are summarized. Ninety-four of 119 cases could be evaluated on the basis of diagnostic and follow-up criteria established by the authors. The diagnostic success rate of gross rhinoscopy with rhinoscopy-assisted biopsy was 83% (78 of 94 evaluated cases). Protracted hemorrhage was a complication in 2 of 109 cases in which rhinoscopy-assisted biopsy was performed. It was concluded that rhinoscopy with rhinoscopy-assisted biopsy contributes important diagnostic information in dogs with nasal disease without the relative invasiveness, expense, and risk of surgery.  相似文献   
38.
M R Rekik  A Silim 《Avian diseases》1992,36(2):237-246
Total RNA of eight avian reovirus isolates and the S1133 strain were compared by RNase T1-oligonucleotide mapping. The viruses were propagated in Vero cell cultures, and viral genomes were extracted from purified virions for comparison. Pairwise comparisons of the oligonucleotide maps showed genetic variation among reovirus isolates ranging from 78% to 99%. The T1 fingerprints of the RNA of isolates 1103, 724, 615, and 684 differed slightly from the standard S1133 strain, suggesting that the vaccine strain might have changed and became part of the circulating reoviruses. In contrast, when compared with the vaccine strain, isolates 902, 644, and 6207 showed greater differences in the fingerprint pattern. This genomic diversity may be due to the differences in immunological status of the affected avian population and/or due to simultaneous coinfection with different reovirus strains.  相似文献   
39.
In the last years the number of isolations of Salmonella enterica subspecies enterica serovar paratyphi B (S. paratyphi B) sent to the national salmonella reference laboratory of Germany has increased steadily. Most of the isolates originated from fowl or poultry products. The bacteriological, serological and biochemical properties of the isolates were investigated. Special emphasis was given to the utilization of d-tartrate which subgroups the serovar. All of them belonged to the d-tartrate positive variant, which is generally considered less virulent for humans and was formerly called S. java. The performance of various tests is compared and in addition the possibility of the spread within the production line is discussed.  相似文献   
40.
The proximal straight tubules of the female mouse kidney exhibit heavy periodic acid Schiff (PAS) staining in their brush borders and numerous cytoplasmic granules. In the present study, the female DBA/2Cr mouse kidney was examined, using various fixatives (formalin, PFA, PLP, Zamboni's, Bouin, or Carnoy solution) and various staining methods (HE, PAS, alcian blue, periodic acid methenamine-silver (PAM), toluidine blue, azan, or Congo red). Under azan and PAM, the staining pattern of the brush border was similar to that of PAS, and few effects of the fixative were observed. Cytoplasmic granules were clearly detected with PAM as well as PAS. However, these granules were not detected with Carnoy solution. Furthermore, distribution of granules differed between PAS and PAM.  相似文献   
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