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91.
92.
Van de Maele I Savary-Bataille K Gielen I Daminet S 《The Canadian veterinary journal. La revue veterinaire canadienne》2008,49(3):283-286
An Akita Inu, living in Belgium, was presented with unusual clinical manifestations of acute babesiosis that included neurological signs and pancytopenia. Diagnosis was made by identifying Babesia canis in the blood smear. Neurological signs resolved after treatment with imidocarb diproprionate. Normalization of hematological abnormalities was gradual over 5 months. 相似文献
93.
Lecollinet S Richardson J 《Comparative immunology, microbiology and infectious diseases》2008,31(2-3):167-190
Natural infection of domestic cats by the feline immunodeficiency virus (FIV) causes acquired immunodeficiency syndrome (AIDS). FIV is genetically related to human immunodeficiency virus (HIV), and the clinical and biological features of infections caused by feline and human viruses in their respective hosts are highly analogous. Although the obstacles to vaccinating against FIV and HIV would seem to be of comparable difficulty, a licensed vaccine against feline AIDS is already in widespread use in several countries. While this seemingly major advance in prevention of AIDS would appear to be highly instructive for HIV vaccine development, its message has not been heeded by investigators in the HIV field. This review endeavours to relate what has been learned about vaccination against feline AIDS, and to suggest what this may mean for HIV vaccine development. 相似文献
94.
Dogs and cats living in a household have previously been identified as a risk factor for human infection with Campylobacter and Helicobacter. In this study, carried out between July 2006 to September 2007, feces and oral swabs from 267 dogs and 61 cats were examined for the presence of the emerging pathogen Arcobacter. Isolates, obtained by an Arcobacter selective isolation procedure, were identified with an Arcobacter species-specific multiplex-PCR and characterized by modified enterobacterial repetitive intergenic concensus PCR. No arcobacters were isolated from cats. Five dogs excreted arcobacters in the feces and two other dogs carried arcobacters in the mouth. In the follow-up, one dog excreted the same Arcobacter butzleri strain for at least 1 week. Six dogs carried each an unique A. cryaerophilus strain although three of them lived in the same family. Therefore, beside the consumption of food and water, contact with dogs is another potential source of Arcobacter infection. 相似文献
95.
Scale-dependent determinants of heterogeneity in fire frequency in a coniferous boreal forest of eastern Canada 总被引:1,自引:0,他引:1
Despite the recognized importance of fire in North American boreal forests, the relative importance of stochastic and determinist
portions of intra-regional spatial variability in fire frequency is still poorly understood. The first objective of this study
is to identify sources of spatial variability in fire frequency in a landscape of eastern Quebec’s coniferous boreal forest.
Broad-scale environmental factors considered included latitude, longitude, human activities and belonging to a given bioclimatic
domain, whereas fine-scale factors included slope, position on the slope, aspect, elevation, surficial deposit and drainage.
The average distance to waterbodies was also considered as a potential intermediate-scale source of variability in fire frequency.
In order to assess these environmental factors’ potential influence, they were incorporated into a proportional hazard model,
a semi-parametric form of survival analysis. We also used a digital elevation model in order to evaluate the dominant aspect
within neighborhoods of varying sizes and successively incorporated these covariates into the proportional hazard model. We
found that longitude significantly affects fire frequency, suggesting a maritime influence on fire frequency in this coastal
landscape. We also found that position on the slope was related to fire frequency since hilltops and upperslopes were subject
to a lower fire frequency. Dominant aspect was also related to fire frequency, but only when characterized within a neighborhood
delimited by 4,000 to 10,000-m radii (5,027–31,416 ha). A 2–6-fold variation in fire frequency can be induced by geographic
and topographic contexts, suggesting a substantial intra-regional heterogeneity in disturbance regime with potential consequences
on forest dynamics and biodiversity patterns. Implications for forest management are also briefly discussed.
Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users. 相似文献
96.
Torsten Seuberlich Catherine Botteron Sylvie L Benestad Hervé Brünisholz Reto Wyss Ulrich Kihm Heinzpeter Schwermer Martina Friess Alexandra Nicolier Dagmar Heim Andreas Zurbriggen 《Journal of veterinary diagnostic investigation》2007,19(1):2-8
Different types of transmissible spongiform encephalopathies (TSEs) affect sheep and goats. In addition to the classical form of scrapie, both species are susceptible to experimental infections with the bovine spongiform encephalopathy (BSE) agent, and in recent years atypical scrapie cases have been reported in sheep from different European countries. Atypical scrapie in sheep is characterized by distinct histopathologic lesions and molecular characteristics of the abnormal scrapie prion protein (PrP(sc)). Characteristics of atypical scrapie have not yet been described in detail in goats. A goat presenting features of atypical scrapie was identified in Switzerland. Although there was no difference between the molecular characteristics of PrP(sc) in this animal and those of atypical scrapie in sheep, differences in the distribution of histopathologic lesions and PrP(sc) deposition were observed. In particular the cerebellar cortex, a major site of PrP(sc) deposition in atypical scrapie in sheep, was found to be virtually unaffected in this goat. In contrast, severe lesions and PrP(sc) deposition were detected in more rostral brain structures, such as thalamus and midbrain. Two TSE screening tests and PrP(sc) immunohistochemistry were either negative or barely positive when applied to cerebellum and obex tissues, the target samples for TSE surveillance in sheep and goats. These findings suggest that such cases may have been missed in the past and could be overlooked in the future if sampling and testing procedures are not adapted. The epidemiological and veterinary public health implications of these atypical cases, however, are not yet known. 相似文献
97.
Michel Truchet Sylvie Lauverjat Michel Lamy Jean Claude Denneulin 《Pesticide biochemistry and physiology》1981,15(3):253-256
No histochemical reaction is available to localize diflubenzuron in tissues. The insecticide can be localized in Pieris tissues by its fluoride atoms, used as tracers in secondary ion microanalysis, which is very sensitive for such light elements. In diflubenzuron-treated insects, especially in females, fluoride intensities are much higher than in controls; images demonstrate a wide distribution of the insecticide in the insect tissues. Thus, besides target organs, i.e., epidermis, diflubenzuron is present in other tissues, such as fat bodies, which may be related to the general metabolic effects and to a detoxification of the insecticide. 相似文献
98.
M. Richert S. Saarnio S. Juutinen J. Silvola J. Augustin W. Merbach 《Biology and Fertility of Soils》2000,32(1):1-7
Short-term (3–6 days) and long-term (27 days) laboratory experiments were carried out to determine the distribution of assimilated
C in the system Phragmites australis (common reed)-waterlogged fen soil after 14C pulse labelling. The investigated system of fen plants and anaerobic organic soil showed different patterns of assimilated
14C distribution when compared to systems with cultivated plants and aerobic mineral soil. Between 90% and 95% of the 14C in the system was found in the reed plants. A maximum of 2% of the assimilated plant 14C was released from the fen soil as CO2 and about 5–9% remained in the soil. The 14C remaining in the waterlogged fen soil of the reed plant had the same amount as that of a cultivated plant in mineral soil,
despite lower 14C-release (i.e. rhizodeposition and root respiration) from reed roots. Assuming that root respiration of fen plants is low,
this indicates that microbial C turnover in waterlogged fen soil is much slower than in mineral soil. The estimated quantity
of the assimilated C remaining in the soil was of an ecologically relevant order of magnitude.
Received: 8 July 1999 相似文献
99.
100.
Renaud Ioos Lise Laugustin Nathalie Schenck Sylvie Rose Claude Husson Pascal Frey 《European journal of plant pathology / European Foundation for Plant Pathology》2006,116(2):171-176
Introns are generally highly polymorphic regions within genes and were proven to be of great interest for discriminating among phylogenetically-close Phytophthora species. Phytophthora ramorum and P. fragariae are considered as quarantine pathogens by the European Union and accurate detection tools are therefore necessary for their monitoring. From introns located in different single copy genes (GPA1, RAS-like, and TRP1), we developed a series of PCR primers specific to P. ramorum and P. fragariae. The specificity of these primers was successfully checked with a wide collection of Phytophthora isolates and a protocol was developed to detect both pathogens directly in infected plant tissues. These genes should be of particular interest for the development of additional species-specific detection tools within the Phytophthora genus. 相似文献