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51.
A pilot study was set up for the first time in France in August 2000, to obtain more precise estimates on the BSE epidemic in France. Three categories of cattle at risk of BSE (found dead on-farm, euthanased and emergency slaughtered) were sampled exhaustively from August 7 to December 22, 2000, in the three regions assumed to be the most affected with BSE in France (Basse-Normandie, Bretagne and Pays de la Loire). The samples were checked by using Prionics tests, and positive samples were confirmed by Western blot or immunohistochemistry. The overall prevalence of positive cattle was 0.16 per cent. Multifactorial logistic regression showed that there was a significantly higher prevalence among cattle from the birth cohorts July 1993 to June 1994 and July 1994 to June 1995, than among those born before July 1993, and among the categories 'euthanased' and 'emergency slaughtered' than among the category 'dead on-farm, and a higher prevalence in the regions Pays de la Loire and Bretagne than in Basse-Normandie. No significant differences in the prevalence of BSE were observed between dairy, beef suckler and mixed herds.  相似文献   
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The postsynaptic density (PSD) is a complex assembly of proteins associated with the postsynaptic membrane that organizes neurotransmitter receptors, signaling pathways, and regulatory elements within a cytoskeletal matrix. Here we show that the sterile alpha motif domain of rat Shank3/ProSAP2, a master scaffolding protein located deep within the PSD, can form large sheets composed of helical fibers stacked side by side. Zn2+, which is found in high concentrations in the PSD, binds tightly to Shank3 and may regulate assembly. Sheets of the Shank protein could form a platform for the construction of the PSD complex.  相似文献   
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Peste des petits ruminants: a suitable candidate for eradication?   总被引:2,自引:0,他引:2  
This year will see the final announcement, accompanied by much justifiable celebration, of the eradication from the wild of rinderpest, the 'cattle plague' that has been with us for so many centuries. The only known rinderpest virus (RPV) remaining is in a relatively small number of laboratories around the world, and in the stockpiles of vaccine held on a precautionary basis. As we mark this achievement, only the second virus ever eradicated through human intervention, it seems a good time to look at rinderpest's less famous cousin, peste des petits ruminants ('the plague of small ruminants') and assess if it should, and could, also be targeted for global eradication.  相似文献   
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Medical records of 33 dogs presented for acute onset, nonprogressive, intracranial dysfunction that had a magnetic resonance imaging diagnosis of brain infarction were reviewed. Postmortem confirmation of brain infarction was available in 10 dogs. All dogs were evaluated by CBC, serum biochemistry, thyroid and adrenal testing, urinalysis, thoracic and abdominal imaging, and cerebrospinal fluid analysis. Results of coagulation profile and arterial blood pressure were available in 32/33 and 28/33 dogs, respectively. On the basis of the imaging findings, infarcts were classified depending on their type (territorial or lacunar) and location within the brain (telencephalic, 10/33; thalamic/midbrain, 8/33; cerebellar, 15/33). No marked associations among location or type of infarct and patient age and sex, occurrence of systemic hypertension, and the presence or absence of a concurrent medical condition were identified. Small breed dogs (< or =15 kg) were significantly more likely to have territorial cerebellar infarcts, whereas large breed dogs (>15 kg) were significantly more likely to have lacunar thalamic or midbrain infarcts. A concurrent medical condition was detected in 18/33 dogs with brain infarcts, with chronic kidney disease (8/33) and hyperadrenocorticism (6/ 33) being most commonly encountered. Of 33 dogs, 10 were euthanized because of the severity and lack of improvement of their neurologic status or the severity of their concurrent medical condition. No association was identified between type or location of infarct and patient outcome. Dogs with concurrent medical conditions had significantly shorter survival times than those with no identifiable medical condition and were significantly more likely to suffer from recurrent neurologic signs because of subsequent infarcts.  相似文献   
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An active surveillance programme for transmissible spongiform encephalopathies (TSES) in sheep and goats was implemented in France in 2002 at abattoirs and rendering plants. The analysis of the results of this programme highlighted three biases: a potentially non-random sampling scheme in both rendering plants and abattoirs, a heterogeneous geographical sampling ratio, and the use of two diagnostic tests of unequal sensitivity. Simulations were run to estimate the prevalence of TSES by taking these biases into account. A comparison of the prevalence of TSES calculated from the raw data with the simulation results showed that the effects of non-random sampling were minor in comparison with the effects of the heterogeneous geographical sampling ratio and the use of two diagnostic tests.  相似文献   
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