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11.
Biological weapons are considered as mass destruction and terror weapons. Terrorism including bioterrorism is the major threat in the future conflicts for our nations. The aim of bioterrorism is more related to the potential disorganisation of the society than to the lethal effects of the agents used. The dramatic consequences cannot be discarded, especially if contagious agents such viral are used. The preparation of specific defence measures is a major challenge for our countries.

The knowledge acquired from the struggle against natural infectious diseases and recent events are essential to improve behaviours to face the biological weapon threats. The defence attitude is based on the anticipation of the threat, the management of the victims, and the restoration of the operational capabilities. This global defence attitude implies six important functions: (i) alert, (ii) detection and diagnosis, (iii) availability of pharmaceutical countermeasures such as vaccine, sera and anti-infectious medicine and products, (iv) medical management of victims, (v) training and information, (vi) research and development.

Passive and active immunoprevention and immuntherapy belong to the approaches discussed in the context of bioterrorism countermeasures. Further researches might be focused on these topics.  相似文献   

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The aim of this study was to evaluate the effect of body positioning immediately after delivery on respiratory and metabolic adaptation to extra-uterine life in newborn calves. One hundred and one Belgian White and Blue calves were delivered at term by an elective caesarean section and were assigned into three categories according to the body position imposed immediately after umbilical cord rupture: 71 calves were placed in lateral recumbency; 16 calves were placed in sternal recumbency and 14 calves were suspended by the hind legs for less than 90 seconds (75 +/- 5 s). Following this initial body position, the calves were allowed to move without restraint. They were examined at birth, 5, 15, 30, 45 and 60 minutes, and 2, 3, 6, 12 and 24 hours after birth by the following measurements: physical examination, heart rate, arterial blood gas analysis, pulmonary function tests using the esophageal balloon catheter technique, arterial and venous blood acid-base balance analysis, rectal temperature, jugular venous blood sampling for the determination of blood glucose, plasma lactate and serum cortisol concentrations, haematologic variables and passive immune transfer variables. Body positioning immediately after delivery clearly influenced respiratory and metabolic adaptation to extra-uterine life in term calves delivered by an elective caesarean section. Systematic sternal recumbency and suspension by the hind legs for less than 90 seconds immediately after umbilical cord rupture had a positive functional impact on postnatal pulmonary mechanics and gas exchange and on postnatal correction of mixed acidosis present at birth, contributing in turn to an enhanced passive immune transfer. These two body positions should be encouraged to improve adaptation at birth in healthy term calves delivered by an elective caesarean section. Evaluation of possible side-effects is required before application in severely asphyxiated calves.  相似文献   
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Objective: To describe a case of confirmed baclofen intoxication in a dog that was successfully treated with hemodialysis and hemoperfusion (HD/HP) and to report the serum baclofen kinetics. Case summary: A 2.5‐year‐old, 23 kg, spayed female Brittany Spaniel‐mix was treated after ingesting 21‐52 mg/kg of baclofen. The dog was comatose and was receiving manual ventilation at the time of presentation. Extracorporeal HD/HP was started 10 hours after admission. Within 3 hours of starting HD/HP the dog began initiating breaths and was extubated 18 hours after admission. Serial serum samples that were obtained during the first 24 hours of hospitalization were later analyzed for baclofen concentrations. The dog had elevated creatine phosphokinase and liver enzymes that correlated with an agitated recovery period. The dog had thrombocytopenia that resolved by 10 days after presentation. New or unique information provided: HD/HP shortened the baclofen serum elimination half‐life from 5 to 1.5 hours in the initial 2 hours of treatment. The intrinsic elimination rate constant (Kintr) for this dog was 0.138/hour and the total elimination rate constant (Ktot) during the first 2 hours of HD/HP treatment was 0.458/hour. In this dog, HD/HP was an effective method for rapidly decreasing serum baclofen concentration after an acute overdose.  相似文献   
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Resistance of Brassica napus (oilseed rape, canola) conferred by three different major resistance genes has been overcome by changes in virulence of Leptosphaeria maculans populations in France and Australia. In South Australia where B. napus cultivars with major gene resistance derived from Brassica rapa ssp. sylvestris were grown extensively, resistance was rendered ineffective within 3 years of commercial release of the cultivar. Disease severity was higher on cultivars with sylvestris-derived resistance than cultivars with polygenic resistance. This Australian situation is compared to that in France, where resistance conferred by the Rlm1 gene was overcome nation-wide in 5 years under commercial cropping practices, and also where a source of resistance introgressed into B. napus from B. juncea was rendered inefficient in 3 years in experimental field plots near Rennes.  相似文献   
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Habitat fragmentation is a major cause for species loss, but its effect on invertebrates with low active dispersal power, like terrestrial gastropods, has rarely been studied. Such species can not cross a hostile habitat matrix, for which the predictions of island theory, such as positive relations between species richness and patch size, should apply. In order to test this prediction, we studied gastropod species diversity by assessing gastropod assemblage characteristics from 35 sites in 19 fragments of deciduous old-growth forests in the Lower Rhine Embayment, Germany. Assemblages differed between larger (≥700 ha) and smaller forests (<400 ha), those of large forests held a higher percentage of forest species. Although α-diversity was similar between the two forest size classes, small forests often comprised matrix species, resulting in a higher β-diversity. Edge effects on the species richness of matrix species were noticeable up to 250 m into the forest. Hierarchical partitioning revealed that distance to disturbances (external edge, internal edges like roads) explained most assemblage variables, whereas forest size and woodland cover within a 1 km radius from the sites explained only a few assemblage variables. Densities of two forest-associated species, Discus rotundatus and Arion fuscus, decreased with forest size. Yet, forest size was positively correlated with richness of typical forest species and densities of Limax cinereoniger. The latter species seems to need forests of >1,000 ha, i.e., well above the size of most fragments. In conclusion, the prediction is valid only for forest species. The response to fragmentation is species specific and seems to depend on habitat specialization and macroclimatic conditions. Jean-Pierre Maelfait: Deceased.  相似文献   
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ObjectiveTo evaluate a thermal nociceptive threshold (TNT) testing device in the donkey, and the influence of potential confounding factors on TNTs.AnimalsTwo groups (Group 1 and Group 2) of eight castrated male donkeys aged 4–9 years, weighing 105–170 kg.MethodsTNTs were measured by heating a thermal probe on skin until an end-point behaviour (threshold temperature) or a cut-out temperature (51 °C) was reached. The withers and the dorsal aspect of the distal limb were used as sites for TNT testing. The effects on TNT of different confounding factors: the limb tested; rate of heating; and ambient temperature were evaluated. Data were analyzed using general linear models, and Mann-Whitney tests, p < 0.05 was considered significant.ResultsEnd-point behaviours (skin twitch or donkey looking at test device) when the thermal probe heated the withers were observed in approximately half of tests. TNT was (mean ± SD) 46.8 ± 2.85 °C. Subsequently the limb was evaluated as the test site in Group 1 followed by Group 2 donkeys; end-point behaviour being a foot-lift. In Group 1, 72% of tests ended in an end-point behaviour but the response rate was lower in Group 2 (20%), although TNTs were similar [(47.6 ± 3.3) and (47.3 ± 3.0) °C respectively] for responding animals. Rate of heating, ambient temperature and laterality (right or left) did not affect thresholds, but mean TNT was significantly higher in the forelimb (48.5 ± 2.8 °C) than the hind limb (47.4 ± 2.8 °C) (p = 0.012).ConclusionsWhen a thermal probe cut-out temperature of 51 °C was used in TNT testing in the donkey a high proportion of tests did not produce an identifiable end point behaviour. Higher cut-out temperatures damaged the skin. Under these conditions, thermal nociceptive threshold testing appears not be an appropriate analgesiometry technique in the donkey.Clinical relevanceTNT testing under these conditions is not suitable form of analgesiometry for donkeys.  相似文献   
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In meat, no detailed studies on the intracellular distribution of oxidized proteins during oxidative stress have been performed, to our knowledge. Therefore, we used fluorescence microscopy to detect and locate protein carbonyls, oxidation products of basic amino acids, generated in bovine M. Rectus abdominis during either exposition to a chemical free radical generating system, or refrigerated storage, or cooking. The technique consisted of an immunohistochemical detection of carbonyls by reaction with the specific probe DNPH (2,4-dinitrophenylhydrazine) followed by the sequential addition of a first antibody against DNPH-carbonylated proteins and a CY3-labeled secondary antibody. The fluorescence of the CY3 probe increased regularly with level of free radical generating system and storage time. Moreover, an important heterogeneity of carbonyl distribution was observed, with a higher oxidation level at the periphery than inside the muscle cells. Cooking induced fluorescence increase only at the periphery of cells. Specific coloration of collagen by Sirius red showed that collagen was not involved in fluorescence. We can deduce that accumulation of oxidized proteins observed in the cell periphery was linked to membrane protein oxidation and not to connective tissue oxidation. Biochemical assays were performed in parallel on membrane and myofibrillar proteins to provide complementary quantitative data on level of oxidized proteins.  相似文献   
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