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排序方式: 共有497条查询结果,搜索用时 92 毫秒
61.
Barker EN Helps CR Neimark H Peters IR Peters W Tasker S 《Veterinary microbiology》2011,149(3-4):478-481
In order to confirm a microscopic diagnosis of 'eperythrozoonosis' made over 40 years ago in a captive owl monkey (Aotus trivirgatus), DNA was extracted from archived fixed and stained blood smears and subjected to generic haemotropic mycoplasma (haemoplasma) quantitative real-time PCR (qPCR) and a human glyceraldehyde-3-phosphate dehydrogenase qPCR as an amplification control. The qPCRs confirmed the extraction of host DNA from the samples and the presence of a haemoplasma species. Partial 16S rRNA and ribonuclease P ribosomal gene fragments were amplified by PCR, cloned and sequenced. Sequence data and phylogeny showed the owl monkey haemoplasma to lie in the haemominutum clade of haemoplasmas, most closely related to 'Candidatus Mycoplasma kahaneii'. This study confirms the use of generic haemoplasma qPCRs to successfully amplify haemoplasma DNA from fixed, stained and archived blood smears from the early 1970s and provides molecular confirmation of the existence of a novel haemoplasma species in an owl monkey, for which the name 'Candidatus Mycoplasma aoti' sp. nov. is proposed. 相似文献
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Pacemaker implantation in a ferret (Mustela putorius furo) with third-degree atrioventricular block.
David Sanchez-Migallon Guzman Joerg Mayer Raffaele Melidone Robert J McCarthy Emily McCobb Anoop Kavirayani John E Rush 《Veterinary Clinics of North America: Exotic Animal Practice》2006,9(3):677-687
A 7.5-year-old castrated male ferret (Mustela putorius furo) was diagnosed with third-degree atrioventricular (AV) block. A monopolar epicardial pacemaker system was implanted, resulting in a regular, paced cardiac rhythm with third-degree AV block at 140 beats per minute. Over the next 2 months, the ferret developed anorexia, interstitial pneumonia, intermittent diarrhea, and hind-limb weakness and had a slow and progressive recovery. The ferret developed clinical signs of congestive heart failure 4 months after the surgery, resulting in its death 3 weeks later. Necropsy results attributed the death to cardiac failure due to extensive myocardial mineralization. To the authors' knowledge this is the first published report of surgical report of surgical pacemaker implantation in a ferret. 相似文献
64.
Applied ecology could benefit from new tools that identify potential movement pathways of invasive species, particularly where
data are sparse. Cost surface analysis (CSA) estimates the permeability (friction) across a landscape and can be applied to
dispersal modelling. Increasingly used in a diversity of applications, several fundamental assumptions that might influence
the outputs of CSA (cost surfaces and least-cost pathways) have yet to be systematically examined. Thus, we explore two issues:
the presumed relationship between habitat preferences and dispersal behaviour as well as the degree of landscape fragmentation
through which an organism moves by modelling a total of 18 sensitivity and dispersal scenarios. We explored the effect of
fragmentation by altering the friction values (generally assigned using expert opinion) associated with patch and linear features.
We compared these sensitivity scenarios in two sites that differed in fragmentation. We also used eastern grey squirrels (Sciurus carolinensis) as an example invading species and compared diffusion models and two contrasting cost surface dispersal scenarios. The diffusion
model underestimated spread because squirrels did not move randomly through the landscape. Despite contrasting assumptions
regarding dispersal behaviour, the two cost surfaces were strikingly similar while the least-cost paths differed. Furthermore,
while the cost surfaces were insensitive to changes in friction values for linear features, they were sensitive to assumptions
made for patch features. Our results suggest that movement in fragmented landscapes may be more sensitive to assumptions regarding
friction values than contiguous landscapes. Thus, the reliability of CSA may depend not only on the range of friction values
used for patches but also the degree of contiguity in the landscape. 相似文献
65.
Dennison AC Van Metre DC Morley PS Callan RJ Plampin EC Ellis RP 《Journal of the American Veterinary Medical Association》2005,227(1):132-138
OBJECTIVE: To compare the frequency of isolation, genotypes, and in vivo production of major lethal toxins of Clostridium perfringens in adult dairy cows affected with hemorrhagic bowel syndrome (HBS) versus left-displaced abomasum (LDA). DESIGN: Case-control study. ANIMALS: 10 adult dairy cattle with HBS (cases) and 10 adult dairy cattle with LDA matched with cases by herd of origin (controls). PROCEDURE: Samples of gastrointestinal contents were obtained from multiple sites during surgery or necropsy examination. Each sample underwent testing for anaerobic bacteria by use of 3 culture methods. The genotype of isolates of C. perfringens was determined via multiplex polymerase chain reaction assay. Major lethal toxins were detected by use of an ELISA. Data were analyzed with multivariable logistic regression and chi2 analysis. RESULTS: C. perfringens type A and type A with the beta2 gene (A + beta2) were the only genotypes isolated. Isolation of C. perfringens type A and type A + beta2 was 6.56 and 3.3 times as likely, respectively, to occur in samples from cattle with HBS than in cattle with LDA. Alpha toxin was detected in 7 of 36 samples from cases and in 0 of 32 samples from controls. Beta2 toxin was detected in 9 of 36 samples from cases and 0 of 36 samples from controls. CONCLUSIONS AND CLINICAL RELEVANCE: C. perfringens type A and type A + beta2 can be isolated from the gastrointestinal tract with significantly greater odds in cattle with HBS than in herdmates with LDA. Alpha and beta2 toxins were detected in samples from cows with HBS but not from cows with LDA. 相似文献
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Erythema ab igne, an old and rare disease in the human literature, is an erythematous, often pigmented, reticular, macular dermatosis that occurs at the site of repeated exposure to moderate heat. We identified lesions consistent with erythema ab igne in five dogs, three cats and one silvered langur (Trachypithecus cristatus[Raffles, 1821]). In dogs and cats, the cutaneous lesion distribution typically reflected chronic exposure to moderate heat during lateral or sternal recumbency. The silvered langur developed cutaneous lesions on the dorsal neck from exposure to a heat lamp. Principal clinical lesions consisted of irregular areas of alopecia (7/9) and erythema (7/9), sometimes with hyperpigmentation (3/9). Principal histological features consisted of karyomegaly (9/9) and keratinocyte atypia (4/9), scattered apoptotic or vacuolated basal cells and/or apoptotic keratinocytes (6/9), mild mixed mononuclear interstitial or interface dermatitis (9/9) with adnexal atrophy (8/9), and a variable number of wavy eosinophilic elastic fibres (9/9). The presence of these cutaneous lesions in an animal indicates that the environment should be evaluated for exposure to chronic moderate heat, and the heat source should be eliminated or modified to prevent further exposure and progression of lesions. 相似文献
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