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81.
SUMMARY This paper reviews the laboratory diagnosis of Leptospira hardjo infection in cattle. Two genotypes of L hardjo, Hardjoprajitno and Hardjobovis, have been identified in cattle, but only Hardjobovis has been isolated in Australia. There are problems with diagnosis and control of bovine leptospirosis. Infection is usually subclinical and the serological titres vary greatly in peak and duration. Leptospires may be excreted in urine for up to 18 months. Low microscopic agglutination test titres may be significant in unvaccinated herds as indicators of endemic infection. Vaccines differ in their composition, and their efficacy is difficult to evaluate. The serological response after vaccination is difficult to differentiate from the response after infection. Pregnant cows that become infected may abort, but this is usually after the serological response has peaked. Therefore, paired serum samples are of little use in diagnosing abortion caused by L hardjo. Fluorescent antibody techniques are more sensitive than dark field microscopy for detection of leptospires in urine and tissue samples. Techniques for culture have improved but are still difficult to perform and take 3 months or longer for results to be known. DNA probes and polymerase chain reaction tests are very sensitive and specific, quick to perform, and can be used on fluid and tissue samples. 相似文献
82.
Chronic hypertrophic pyloric gastropathy in 14 dogs 总被引:1,自引:0,他引:1
SUMMARY Ten mate and 4 female dogs with chronic hypertrophic pyloric gastropathy were seen at the Sydney University Veterinary Teaching Hospital in the period 1982–88. The most commonly affected breeds were the Shihtzu and Maltese. The mean age was 8.2 yr and the mean body weight 6.5 kg. The most common clinical signs were vomiting, weight loss, polydipsia and depression. Hypokalaemia was present in 11 of 12 dogs examined and hypochloraemia in 10 of 11 dogs examined. Five of the six dogs that had blood gases measured were found to have a metabolic alkalosis. Surgery was performed on 13 dogs; pyloromyotomy 7, pyloroplasty 4, gastroduodenostomy 2. There was a recurrence of symptoms in one pyloromyotomy dog, and fatal ulceration and perforation of the cardia occurred in one pyloroplasty case. The remaining 11 dogs had a mean known symptom-free survival time of 20 mo. This study confirms the preponderance of affected males, identifies electrolyte and blood gas disturbances as significant complications of chronic hypertrophic pyloric gastropathy, and suggests that relatively minor surgery (pyloromyotomy) may have a place in the treatment of a selected subgroup of cases. 相似文献
83.
84.
Lucas Silva Padovani Alcione Maria Soares Dutra Oliveira Bernardo Carvalho Dutra Fernando Oliveira Costa Peterson Antônio Dutra Oliveira 《Anatomia, histologia, embryologia》2020,49(6):798-804
The knowledge of anatomical variations of the posterior superior alveolar artery (PSAA) is very important in surgeries for maxillary sinus (MS) elevation and subsequent insertion of dental implants, avoiding common and serious surgical complications. The main objective of this study was to analyse important anatomical variations of the PSAA by means of cone beam computed tomography (CBCT) examinations. 180 tomographic CBCT were analysed, and MS was divided into three equal regions: (I) anterior, (II) intermediate and (III) posterior. Variables evaluated were the visualisation of the artery, distance from the artery to the ridge crest, distance from the artery to the sinus floor, alveolar ridge height and arterial diameter. The PSAA visualisation was more prevalent in males and region III (76.7%). The distance from the artery to the sinus floor presented no significant difference between regions II and III, with both regions showing significantly lower values than region I. A significant difference was observed in the diameter of the arteries with higher prevalence of diameters >1.0 mm in males and <1.0 mm in females. The PSAA can be well visualised frequently with a CBCT, and differences in artery diameter were observed in relation to gender (males > females). Additional care is recommended when it is necessary to extend surgeries to the posterior MS region, avoiding haemorrhages that are associated with failures in these procedures. 相似文献
85.
RW Graham EL Lundelius MA Graham EK Schroeder RS Toomey E Anderson AD Barnosky JA Burns CS Churcher DK Grayson RD Guthrie CR Harington GT Jefferson LD Martin HG McDonald RE Morlan HA Semken SD Webb L Werdelin MC Wilson 《Science (New York, N.Y.)》1996,272(5268):1601-1606
Analyses of fossil mammal faunas from 2945 localities in the United States demonstrate that the geographic ranges of individual species shifted at different times, in different directions, and at different rates in response to late Quaternary environmental fluctuations. The geographic pattern of faunal provinces was similar for the late Pleistocene and late Holocene, but differing environmental gradients resulted in dissimilar species composition for these biogeographic regions. Modern community patterns emerged only in the last few thousand years, and many late Pleistocene communities do not have modern analogs. Faunal heterogeneity was greater in the late Pleistocene. 相似文献
86.
Role of Gene Interactions in Hybrid Speciation: Evidence from Ancient and Experimental Hybrids 总被引:6,自引:0,他引:6
LH Rieseberg B Sinervo CR Linder MC Ungerer DM Arias 《Science (New York, N.Y.)》1996,272(5262):741-745
The origin of a new diploid species by means of hybridization requires the successful merger of differentiated parental species' genomes. To study this process, the genomic composition of three experimentally synthesized hybrid lineages was compared with that of an ancient hybrid species. The genomic composition of the synthesized and ancient hybrids was concordant (rs = 0.68, P < 0.0001), indicating that selection to a large extent governs hybrid species formation. Further, nonrandom rates of introgression and significant associations among unlinked markers in each of the three synthesized hybrid lineages imply that interactions between coadapted parental species' genes constrain the genomic composition of hybrid species. 相似文献
87.