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排序方式: 共有491条查询结果,搜索用时 15 毫秒
1.
In the period December 1967 through April 1969 eight spontaneous cases of pseudorabies in Danish red foxes were demonstrated by virus isolation. One fox had been kept in captivity, the remaining seven were free-living. Five of the foxes were found dead, while three, presenting abnormal behaviour when encountered, had been killed. 相似文献
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Repeat patient testing shows promise as a quality control method for veterinary hematology testing 下载免费PDF全文
Bente Flatland Kathleen P. Freeman 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2018,47(2):252-266
Background
Repeat patient testing‐based quality control (RPT‐QC) is a potential method for veterinary laboratories (eg, that have a limited budget for quality commercial control material [QCM] or that wish to use material with a species‐specific matrix).Objectives
To determine whether total error (TEa), probability of error detection (Ped), and probability of false rejection (Pfr) similar to that achievable with QC materials can be controlled using RPT‐QCMethods
Control limits (WBC, RBC, HGB, HCT, MCV, and PLT) for the Advia 120 (n = 23) and scil Vet ABC (n = 22) were calculated using data from normal canine specimens from a routine caseload. Specimens were measured at accession and again after 24 hours. Control limits were validated using 23 additional canine specimens tested similarly. Achievable TEa, Ped, and Pfr were investigated using the Westgard EZRules3 and compared to those achievable with commercial QCM.Results
Theoretical performance of RPT‐QC and commercial QCM‐QC are similar for 1‐3s with both n = 1 and 1‐3s with n = 2 for all measurands and both instruments. Achievable TEa values for RPT‐QC were close to ASVCP recommendations for most measurands; exceptions were PLT (both instruments) and WBC (scil Vet ABC).Conclusions
Repeat patient testing‐based quality control advantages include a species‐specific matrix, low‐cost, and absence of QC material deterioration over time (since a fresh specimen is used each day). A potential disadvantage is daily access to normal canine specimens. A challenge is determining control limits, which has a subjective element. Further study is needed to confirm actual RPT‐QC performance and to determine if RPT‐QC with abnormal patient specimens is feasible. 相似文献4.
Evidence for genetic distinction among sympatric ecotypes of Arctic char (Salvelinus alpinus) in south‐western Alaskan lakes 下载免费PDF全文
Shannan L. May‐McNally Thomas P. Quinn Pamela J. Woods Eric B. Taylor 《Ecology of Freshwater Fish》2015,24(4):562-574
Resource polymorphism may play an important role in the process of speciation. The Arctic char (Salvelinus alpinus) exhibits great phenotypic and genetic diversity across its range, making it an ideal species for studies of resource polymorphism and divergence. Here, we investigated genetic variation at 11 microsatellite loci among 287 Arctic char from five isolated yet proximate postglacial lakes in south‐western Alaska that were previously examined for resource polymorphism. Significant differences in pairwise FST were detected among all lakes (range from 0.05 to 0.28, all P < 0.02). In one lake (Lower Tazimina Lake), we found evidence for two genetic groups of char and for significant differences in the distribution of microsatellite variability among at least two of the three previously described body size morphotypes (‘large’‐, ‘medium’‐, and ‘small’‐bodied char; maximum FST = 0.09; differences in admixture proportions). We also found a significant association between genetic admixture proportions and gill raker counts among body size morphs (r = ?0.73, P < 0.001). Our data represent the first record of genetically distinct sympatric morphs of Arctic char in Alaska and provide further evidence that differences in morphology associated with feeding (gill rakers) and growth trajectories reflect niche diversification and promote genetic divergence in Holarctic populations of Arctic char. 相似文献
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Eleven strains of the avian pathogen Mycoplasma synoviae were evaluated for the presence of sialidase activity with the use of the fluorogenic substrate 2'-(4-methylumbelliferyl)-alpha-D-N-acetylneuraminic acid and the sialidase inhibitor 2-deoxy-2,3- didehydro-N-acetylneuraminic acid. The kinetics of in vitro growth in modified Frey medium were also assessed for each strain. Five strains had been isolated from clinically symptomatic chickens, and strains WVU 1853T and K3344 have been demonstrated to be capable of reproducing disease in specific-pathogen-free chickens. All strains exhibited sialidase activity, although the amount varied 65-fold among strains (P < 0.0001) from 1.3 x 10(-7) to 2.0 x 10(-9) activity units per colony-forming unit. Strains originally isolated from clinically symptomatic birds had more (P < 0.05) sialidase activity than strains from asymptomatic birds. Strain WVU1853T exhibited the most sialidase activity (P < 0.0001) and grew to the highest culture density (P < 0.0001) among strains, but across strains, the rank correlation of growth rate with sialidase activity was not significant. Negligible activity was detected in conditioned culture supernatant fluid. This is the first report of sialidase activity in pathogenic strains of M. synoviae, which suggests a potential enzymatic basis for virulence of the organism. 相似文献
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Nabity MB Boggess MM Kashtan CE Lees GE 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(3):425-430
BACKGROUND: Interpretation of serial urine protein:creatinine (UPC) values is confounded by a lack of data regarding random biologic variation of UPC values in dogs with stable glomerular proteinuria. HYPOTHESIS: That there is minimal day-to-day variability in the UPC of dogs with unchanging proteinuria and the number of measurements needed to reliably estimate UPC varies with the magnitude of proteinuria. ANIMALS: Forty-eight heterozygous (carrier) female dogs with X-linked hereditary nephropathy (XLHN) causing stable proteinuria. METHODS: Urine samples were obtained daily by cystocentesis for 3 consecutive days on 183 occasions (549 samples). The UPC was measured for each sample with a single dry-film chemistry auto-analyzer. Data were analyzed retrospectively by a power of the mean model because the variance of UPC values within the 3-day evaluation periods increased as the magnitude of proteinuria increased. RESULTS: To demonstrate a significant difference (P < .05) between serial values in these proteinuric dogs, the UPC must change by at least 35% at high UPC values (near 12) and 80% at low UPC values (near 0.5). One measurement is adequate to reliably estimate the UPC when UPC <4, but 2-5 determinations are necessary at higher UPC values. CONCLUSIONS AND CLINICAL IMPORTANCE: These guidelines for interpretation of serial UPC values in female dogs with XLHN may also be helpful for interpretation of UPC values in dogs with other glomerulopathies. 相似文献
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Ray KA Warnick LD Mitchell RM Kaneene JB Ruegg PL Wells SJ Fossler CP Halbert LW May K 《Preventive veterinary medicine》2007,79(2-4):204-223
The objective of this study was to determine the prevalence of antimicrobial resistance among Salmonella isolated from dairy herds in New York, Minnesota, Michigan, and Wisconsin, USA. Serogroup and antimicrobial susceptibility characteristics were determined for Salmonella from cattle and environmental samples collected during August 2000–October 2001 as part of a longitudinal study where 129 herds were visited at 2-month intervals. Salmonella isolates were tested (using a broth microdilution method) for susceptibility to amoxicillin/clavulanic acid, ampicillin, ceftiofur, ceftriaxone, cephalothin, chloramphenicol, ciprofloxacin, gentamicin, kanamycin, nalidixic acid, streptomycin, sulfamethoxazole, tetracycline, and trimethoprim/sulfamethoxazole. Of the 1506 isolates tested for minimum inhibitory concentrations to these 14 antimicrobial agents, 81.2% were pan-susceptible and for most herds (81.6%) the predominant antimicrobial resistance pattern was pan-susceptible. At least 1 Salmonella isolate resistant to 5 or more antimicrobial agents was found on 23.6% of herds. This resistance phenotype was most common among serogroups B and E1 and among samples from calves and farmer-designated sick cows. Resistant samples most frequently exhibited resistance to tetracycline, streptomycin, and/or ampicillin. No samples were resistant to ceftriaxone (though 13 were in the intermediate range), and very few samples were resistant to ciprofloxacin (n = 1), nalidixic acid (n = 5), or trimethoprim/sulfamethoxazole (n = 7). 相似文献
9.
Susan May F. Calumpang 《Pest management science》1996,46(1):93-102
Filipino farmers resist wearing protective garments while spraying, preferring to wear long-sleeved cotton polyester shirts and short or long trousers. The exposure of farmers while wearing this attire and spraying was assessed to determine what degree of protection it afforded farmers under tropical conditions. Absorbent pads were placed on the outer and inner wear on various body parts. Applicators sprayed parathion-methyl on fruiting string beans at the recommended rate and residues were analyzed by gas chromatography. Each farmer had a characteristic spraying pattern which resulted in peculiar residue levels in some body parts. Inner exposure did not exceed the tolerable dermal exposure level during warm days while using proper spraying techniques. The use of long-sleeved cotton polyester shirt and thick polyester trousers provides, to a certain degree, protection for farmers during warm days. A change of clothing would be a more acceptable measure for farmers than wearing uncomfortable and impractical protective garments. The following spraying techniques reduced farmer exposure: fully outstretched arm, minimal body twisting and smooth hand movements. The use of thick polyester long trousers, gloves or a suitable substitute and the removal of weeds within the crop area also reduce farmer exposure to insecticides. Re-designing the bottle to include a plastic lip, in order to avoid spillage, is also recommended to reduce exposure during the critical mixing stage. Laundering the shirt immediately after use removes a significant amount of residues (96–97%) and contributes towards the protection of farm workers. These recommendations should provide useful data for incorporation in farmer-training programes on the proper use of pesticides. 相似文献
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C Ross K K Haussler J D Kenney D Marks J J Bertone K Henneman K J May 《Veterinary Clinics of North America: Equine Practice》2001,17(2):351-377
Vigorous and prolonged effort is required to gain true mastery of the healing arts. Conventional and complementary medicine have complementary strengths and weaknesses. Like the yin and yang of traditional Chinese medicine, they naturally flow into one another by a process of induction, creating balance. Integrative medicine is the frontier; it is the future. If we are to progress beyond our current understanding and ability to heal, we must work with theoretic models that allow us and our perception to operate "outside the box." For some, this understanding is intuitive. It is through cooperative and collaborative efforts of intuitively adept and technologically adept minds that we can integrate and advance our understanding; increase our ability to predict, prevent, and diagnose disease; and expand our therapeutic options. 相似文献