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ObjectiveTo assess the occurrence of Leptospira spp serovar Hardjo among Zebu cattle in some livestock producing areas of Kaduna State, Nigeria.MethodsSera samples were obtained from 164 Zebu breed of cattle above one year osf age in seven cattle farms were screened for antibodies to Leptospira spp. serovar Hardjo using Enzyme linked immunosorbent assay (ELISA).ResultsAntibodies to Leptospira spp. serovar Hardjo were detected in eighteen (10.98%) out of the 164 animals sampled. There was no significant difference (P>0.05) in seropositivity between the different age groups or between different Zebu breeds.ConclusionThe presence of Leptospirosis among the Zebu breeds of cattle may poses a threat to livestock production and has public health implication due to its zoonotic potential.  相似文献   
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Liver tumours in children are rare and their prognosis are poor. Through a cross and retrospective study, we examined the epidemiological, clinical and therapeutic aspects on a number of patients in our hospital to try and improve the management of cases. This study involved 66 children admitted to the pediatric oncology unit of University Hospital of Treichville in Abidjan between 1991 and 2007. The average age of children was 7.2 years and the sex ratio of 1.4. 42 children lived in the countryside and 52 children were from disadvantaged areas. 63.2% of children were not vaccinated against hepatitis B. The abdominal mass was the primary sign of discovery and these tumours were dominated in both their primitive and secondary forms by the Burkitt's lymphoma.  相似文献   
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Amiez C  Sallet J  Procyk E  Petrides M 《NeuroImage》2012,63(3):1078-1090
The present functional magnetic resonance imaging (fMRI) experiment aims at clarifying the role of the rostral anterior cingulate cortex (rACC) in the evaluation of feedback in a deterministic environment. We tested, in particular, the response of the rACC to the detection of different types of feedback, and to varying levels of outcome expectancy. We used a problem-solving task in which subjects had to discover, in successive trials, which one of the four presented stimuli was associated with a positive feedback, the other ones being associated with error feedback. In this task, two periods alternated: 1. an exploratory period in which error feedback indicated to adapt the following response appropriately (and continue to explore), and first positive feedback indicated to change strategy (i.e. to shift from explorative to exploitative behavior), and 2. an exploitative period in which subjects had to repeat the correct choice. The rACC is recruited in the exploratory period during the analysis of both error and first correct positive feedback. In addition, the rACC activity was modulated by positive reward prediction error values (i.e. the difference between obtained and expected feedback). Altogether, these results reveal the critical role of the rACC in the evaluation of salient feedback for learning optimal strategies.  相似文献   
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