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51.
The Distribution of Staphylococcus aureus in a Poultry Processing Plant   总被引:9,自引:6,他引:3  
A set of phages previously isolated from poultry strains of Staphylococcus aureus was used to type such isolates from poultry before, during and after processing in a poultry plant. Certain poultry phage types were found to be associated with the live birds rather than the processed carcases. Strains lysed by phages from this group may represent a specific 'poultry'biotype. A site of cross-contamination within the plant was discovered.  相似文献   
52.
When particles of Kashmir bee virus (KBV) and sacbrood virus (SBV) were fed to larvae of the honey bee, Apis mellifera, in Australian colonies, the resulting pupae became in apparently infected. There was no statistically significant difference in the susceptibility of 1, 2, 3 or 4-day-old larvae for either virus, but 5-day-old larvae were significantly less susceptible to SBV than younger larvae. There was no significant difference in the proportions of pupae that became in apparently infected when, as larvae, they were fed various concentrations of each virus, but significantly more larvae were removed from their cells when fed concentrated preparations of each virus than when fed diluted preparations. Susceptible larvae that became in apparently infected with KBV and SBV developed normally into in apparently infected pupae and later, emerged as in apparently infected worker bees.  相似文献   
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The results of routine use of the indirect fluorescent antibody (FA) technique using the Spicer-Edwards H antisera set are reported for a range of agricultural and food samples. The FA technique was used on samples after the pre-enrichment incubation period in the proposed ISO method for isolation of salmonellas. The numbers of FA false positive samples ( ca. 5% overall) and FA false negative samples ( ca. 1·3%) were low, but some originally FA false positive results were later shown to be false negative cultural results.  相似文献   
58.
Between January 1989 and May 1990, the Department of Cytology of Llandough Hospital examined 784 pleural fluid cytological preparations, 99 of which were also examined as paraffin wax sections of clots that had formed. to assess whether this practice yields worthwhile information, we reviewed the cytology and clot sections of 99 patients with pleural effusions and correlated the results with subsequent histology and review of clinical case notes. the specificities of each method separately and when combined was high: 92% clot section, 85% smear cytology and 85% combined. the sensitivity using clot section alone was 49%, smear cytology alone 46% and in combination, 54%. Analysis showed no significant difference between these sensitivities. When pleural fluid clot formation occurs, we recommend the continued examination of clot sections, since it yields an increase in positive diagnoses, albeit not statistically significant. Entre janvier 1989 et mai 1990, 784 préparations cytologiques de liquides pleuraux ont été examinées dans le département de Cytologie de l'Hôpital Llandough. Parmi ces 784 cas, 99 contenaient un coagulum qui a fait l'objet également de coupes histologiques apres inclusion en paraffine. Afin de déterminer si cette pratique apporte une information intéressante, la cytologie de ces 99 patients et les coupes obtenues á partir du coagulum ont été revues, puis les résultats one été corrélés avec les résultats histologiques et avec I'analyse des données cliniques. Les valeurs de la spécificité de chacune des méthodes et des deux méthodes associées sont élevées: 92% pout les coupes du coagulum, 85% pour la cytologie d'étalement et 85% pour les deux méthodes combinées. Les valeurs pour la sensibilité sont de 49% pour les coupes de coagulum, de 46% pour la cytologie seule et de 54% en combinant les deux methodes. L'analyse ne met pas en évidence de différence significativé de sensibilitk entre les méthodes. Lorsqu'un coagulum s'est formé dans un liquide pleural, nous recornmandons de poursuivre la pratique de l'inclusion en paraffine et de coupe de ce coagulum puisque cette pratique aboutit à une augmentation du taux de diagnostics positifs, même si la différence n'est pas démontrée statistiquement. Das zytologische Labor des Llandough Hospitals untersuchte zwischen Januar 1989 und Mai 1990 784 Pleurapunktate. Von 99 wurden ausserdem paraffinge-schnittone Clotpräparate angefertigt. Um den Wert dieses Verfahrens zu überprüfen wurden diese Ergebnisse mit späteren histologischen Proben und der Patientengeschichte korreliert. Die Spezifitaten betrugen: 92% für Clot, 85% für Ausstriche und 85% für die Kombination. Die Sensitivitäten: 49% für Clot, 46% für Ausstriche und 54% für die Kombination. Die Unterschiede sind statistisch nicht signifikant, trotzdem sollten Gerinnsel bei Vorhandensein histologisch verarbeitet werden.  相似文献   
59.
About half (49%) of strains of Staphylococcus aureus isolated from poultry were non-typable with the international human set of phages, and 55% were biotype B according to the biochemical identification scheme of Hájek & Maršálek (1971, 1973). A furthest neighbour clustering strategy and principal coordinate analysis based on 17 biochemical tests made clear distinctions between biotype B strains and a group of biotype A and intermediate strains. Overall 62% of strains were enterotoxigenic, the majority producing enterotoxin A. Significantly fewer intermediate strains than biotype A or B strains were enterotoxigenic. Starch gel zymograms of intracellular esterases showed a general correlation with the biotyping and phage typing results.  相似文献   
60.
Genetic constitution in the intertidal gastropod Nucella lapillus (L.) influences shell shape, growth rate and physiology. Clinal variation in these traits along a 5 km stretch of coastline in south Devon can be related to environmental variation in temperature and desiccation stress. We have examined mtDNA variation along this shore to investigate whether the cline represents primary or secondary contact. Two distinct mtDNA haplotypes were found which exhibit coincident step clines with karyotypic, allozymic and phenotypic variation and covary with the environmental pressures of temperature and desiccation. These results are interpreted in the context of the wider scale distribution of genetic and phenotypic variation in N. lapillus. It is suggested that the shore studied may represent one of a number of regions of secondary contact within a mosaic hybrid zone in N. lapillus , where coadapted phenotypic variation correlates with habitat and the position of the clines represents an environmental transition.  相似文献   
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