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排序方式: 共有774条查询结果,搜索用时 31 毫秒
121.
Jennifer Fazakerley Nicola Williams Stuart Carter Neil McEwan Tim Nuttall 《Veterinary dermatology》2010,21(6):578-585
Staphylococcus pseudintermedius is part of the normal canine flora but frequently causes pyoderma in canine atopic dermatitis (AD). This study aimed to determine whether particular S. pseudintermedius strains were associated with AD and/or pyoderma. Ninety‐six S. pseudintermedius isolates from the ear, nares, perineum and lesions of 21 atopic and 16 healthy dogs were lysed with proteinase K and digested with 40 U SmaI. Restriction products were separated using pulsed‐field gel electrophoresis (PFGE) with an Oxford S. aureus control and lambda‐ladder DNA concatomer markers. A dendrogram was constructed by the unweighted pair group method. All isolates showed a ≥56% similarity coefficient. Nine distinct PFGE clusters were identified, as follows: five from both atopic and healthy dogs; three from atopic dogs only; and one from healthy dogs only. Nine clusters were isolated from the nares, eight from the perineum, five from the ears and six from pyoderma lesions. There were no significant differences in the frequency of isolation from atopic or healthy skin, body sites or infected lesions for any of the clusters. Two of six healthy dogs and 18 of 20 atopic dogs with multiple isolates had closely related isolates (less than three band differences) at more than one sampling site. Isolates from pyoderma lesions were closely related to at least one mucosal isolate in 11 of 16 dogs. Staphylococcus pseudintermedius isolates appear to be heterogeneous, and colonization or infection of atopic skin was not associated with any particular strain or cluster of strains. 相似文献
122.
Mila Freire DVM James Brown DVM Diplomate ACVR Ian D. Robertson BVSc Diplomate ACVR Anthony P. Pease DVM MS Diplomate ACVR Jonathan Hash BA Stuart Hunter DVM Diplomate ACVP Wendy Simpson DVM Andrea Thomson Sumrell RVT 《Veterinary surgery : VS》2010,39(5):545-552
Objective: To (1) determine prevalence of radiographically detectable meniscal mineralization in domestic cats and (2) to evaluate the association between meniscal mineralization and degenerative joint disease (DJD). Study Design: Prospective study. Animals: Client‐owned cats (n=100) and 30 feline cadavers. Methods: Randomly selected client‐owned cats were used to determine the prevalence of meniscal mineralization. Stifles from feline cadavers were used to evaluate the relationship between meniscal mineralization (using high‐resolution X‐ray), radiographic DJD, and cartilage damage. Menisci were evaluated histologically. Results: Forty‐six percent of the client‐owned cats had meniscal mineralization detected in 1 or both stifles. Pain scores were not significantly different between stifles with meniscal mineralization and those with no radiographic pathology (P=.38). Thirty‐four of 57 cadaver stifles had meniscal mineralization, which was always located in the cranial horn of the medial meniscus. Percentage mineralization of the menisci was significantly correlated with the cartilage damage score of the medial femoral (r2=0.6; P<.0001) and tibial (r2=0.5; P<.0001) condyles as well as with the total joint cartilage damage (r2=0.36; P<.0001) score and DJD score (r2=0.8; P<.0001). Conclusion: Meniscal mineralization is a common condition in domestic cats and seems to indicate medial compartment DJD. Clinical Relevance: Clinical significance of meniscal mineralization is uncertain. Further work is needed to determine if the meniscal mineralization is a cause, or a consequence of joint degeneration. 相似文献
123.
Frederick B. Pierson C. Jason Williams Patrick R. Kormos Stuart P. Hardegree Patrick E. Clark Benjamin M. Rau 《Strength and Conditioning Journal》2010,63(6):614-629
Woodland encroachment on United States rangelands has altered the structure and function of shrub steppe ecosystems. The potential community structure is one where trees dominate, shrub and herbaceous species decline, and rock cover and bare soil area increase and become more interconnected. Research from the Desert Southwest United States has demonstrated areas under tree canopies effectively store water and soil resources, whereas areas between canopies (intercanopy) generate significantly more runoff and erosion. We investigated these relationships and the impacts of tree encroachment on runoff and erosion processes at two woodland sites in the Intermountain West, USA. Rainfall simulation and concentrated flow methodologies were employed to measure infiltration, runoff, and erosion from intercanopy and canopy areas at small-plot (0.5 m2) and large-plot (13 m2) scales. Soil water repellency and vegetative and ground cover factors that influence runoff and erosion were quantified. Runoff and erosion from rainsplash, sheet flow, and concentrated flow processes were significantly greater from intercanopy than canopy areas across small- and large-plot scales, and site-specific erodibility differences were observed. Runoff and erosion were primarily dictated by the type and quantity of ground cover. Litter offered protection from rainsplash effects, provided rainfall storage, mitigated soil water repellency impacts on infiltration, and contributed to aggregate stability. Runoff and erosion increased exponentially (r2 = 0.75 and 0.64) where bare soil and rock cover exceeded 50%. Sediment yield was strongly correlated (r2 = 0.87) with runoff and increased linearly where runoff exceeded 20 mm·h?1. Measured runoff and erosion rates suggest tree canopies represent areas of hydrologic stability, whereas intercanopy areas are vulnerable to runoff and erosion. Results indicate the overall hydrologic vulnerability of sagebrush steppe following woodland encroachment depends on the potential influence of tree dominance on bare intercanopy expanse and connectivity and the potential erodibility of intercanopy areas. 相似文献
124.
Rapid early growth of tree seedlings is critical to the success of plantation establishment. We investigated the effects of
seedling size (small and large) and container types (small [Lannen 121], medium [Lannen 81] and large [Forestry Tube]) in
the nursery and the effects of mammal browsing after planting on growth of Eucalyptus globulus in Tasmania’s Southern Forests. After planting, seedlings were either exposed to browsing or protected from browsing by wire-mesh
cages until age 6 months. Low browsing pressure resulted in around 20% and 5–10% of foliage being browsed in the large and
small size categories, respectively, between 1 and 3 months after planting the uncaged treatment. 6 months after planting,
height growth increment was lower, and 4 years after planting, mortality was higher in uncaged large than caged large seedling
treatments. Six and twelve months after planting, seedlings raised in Forestry Tube containers had significantly greater height
increment and root collar diameter relative to other treatments. By 4 years after planting, trees of the small seedling treatment
had significantly greater diameter than those of the large seedling treatment, but there was no effect of container type treatment.
Four years after planting there was no effect on diameter growth by browsing of <30% of foliage up to 3 months after planting,
although there was greater incidence of double leaders in trees that had been browsed as seedlings. Small seedlings produced
more growth 4 years after planting than large seedlings of E. globulus. 相似文献
125.
Fatty Acid Composition of Three Rice Varieties Following Storage 总被引:5,自引:0,他引:5
Zhongkai Zhou Chris Blanchard Stuart Helliwell Kevin Robards 《Journal of Cereal Science》2003,37(3):327-335
The petroleum ether extractable lipids (PEE-L) and aqueous propan-1-ol extractable lipids (PWE-L) of three varieties of rice were determined gravimetrically and characterised by fatty acid profiles. The content of PEE-L (22·5–28·2 mg g−1) was higher than that of PWE-L (7·4–11·5 mg g−1) in brown rice with the situation reversed in milled rice (3·0–4·5 mg g−1vs. 7·2–8·7 mg g−1). The ratio of unsaturated fatty acid to saturated fatty acid was about two times higher in PEE-L than that in PWE-L for both brown and milled rice reflecting the selective complexation of saturated fatty acids. Rice storage at 37 °C resulted in some minor but statistically significant changes in the fatty acid profile. In the case of brown rice, the only notable changes were a reduction in the amounts of oleic and linoleic acids in the aqueous propan-1-ol extractable fatty acid fraction (PWE-FA) following storage at the higher temperature. Milled rice of all three varieties showed a decrease in linoleic acid content of PEE-L following storage at 37 °C for 4 and 7 months compared to storage at 4 °C. There was no change in fatty acid contents of PWE-L of milled rice when stored at 4 and 37 °C for 4 and 7 months. This implies that the PWE-L (or bound lipids) were more stable than PEE-L (or free lipids) during storage. 相似文献
126.
127.
Fuchs T Nathues H Koehrmann A Andrews S Brock F Klein G Beilage Eg 《Berliner und Münchener tier?rztliche Wochenschrift》2011,124(1-2):22-27
The objective of this study was to determine the effect of using a gonadotrophin releasing factor (GnRF) vaccine on growth performance of male pigs. Vaccinated pigs were compared with surgically castrated pigs and entire males under conventionally managed farm conditions. Male pigs were randomly assigned to three treatment groups: pigs surgically castrated during the first week of life (group "C", n=274), pigs immunised twice during the fattening period with a GnRF vaccine, the first when 13-14 weeks of age and the second when 20-21 weeks of age (group "V" n=280) and entire males (group "E", n=56). Average daily weight gain (ADG) was measured during the study. Additionally, feed conversion ratio (FCR) as defined by feed intake/weight gain and feed consumption was assessed during the fattening period. No difference in the ADG during the fattening period could be determined between "C" and "V". From the start of the study until slaughter at study day 160/173 the ADG in group "E" was lower (625 g/day; P) than in group "C" (681 g/day; P < 0.001) and group "V" (675 g/day; P < 0.01). The FCR during the fattening period until study day 160, three days before the first batch of pigs were slaughtered at 24-25 weeks of age, was higher in group"C" (2.72 kg feed intake/kg weight gain) compared with group "V" (2.44 kg feed intake/kg weight gain; P < 0.001) and group "E" (2.44 kg feed intake/kg weight gain; P <0.01). Pigs in group "V" performed similarly to those in group "E" until the second vaccination (day 135) after which time they showed a substantial increase in feed intake and ADG, while retaining an FCR advantage over group C. 相似文献
128.
129.
Witchell TD Hoke DE Bulach DM Coutts SA Driesen SJ Cordwell SJ Adler B 《Veterinary microbiology》2011,149(1-2):157-162
The Vsp proteins are the major outer membrane proteins of Brachyspira hyodysenteriae, the causative agent of swine dysentery. Eight vsp genes have been identified in B. hyodysenteriae strain B204, arranged into two four-gene loci, and at least two of the corresponding proteins are produced in vitro. The aims of this study were to characterise the vsp genes of the virulent Australian B. hyodysenteriae strain X576 and their corresponding proteins, Genomic sequence comparison with strains B204 and WA1 demonstrated that the number of vsp genes varies between B. hyodysenteriae strains, although the chromosomal locations of the vsp gene loci are consistent. We identified two additional vsp-like genes, designated vspI and vspJ, in each of the three strains. Double SDS-PAGE was used to demonstrate that Vsp proteins of B. hyodysenteriae strain X576 form multimeric protein complexes in the outer membrane that are stable in 6M urea but dissociate after boiling. The Vsp complexes primarily consisted of VspF but also contain VspE and VspI. VspD was also found in a series of complexes slightly larger than the more abundant VspF complexes. Vsp proteins are purported to be antigenic; however little direct data are available to support this claim. In this study convalescent pig sera did not bind denatured Vsp proteins by Western blotting, but did bind the Vsp complexes on Western blots, showing that conformational epitopes may be important in immune recognition of these major outer membrane proteins. This is the first definitive demonstration of the antigenicity of these proteins in swine dysentery. 相似文献
130.
Stuart W. Paine Jane Bright James P. Scarth Pamela R. Hincks Clive M. Pearce Colette Hannan Marc Machnik Lynn Hillyer 《Journal of veterinary pharmacology and therapeutics》2020,43(2):162-170
In equine and racing practice, detomidine and butorphanol are commonly used in combination for their sedative properties. The aim of the study was to produce detection times to better inform European veterinary surgeons, so that both drugs can be used appropriately under regulatory rules. Three independent groups of 7, 8 and 6 horses, respectively, were given either a single intravenous administration of butorphanol (100 µg/kg), a single intravenous administration of detomidine (10 µg/kg) or a combination of both at 25 (butorphanol) and 10 (detomidine) µg/kg. Plasma and urine concentrations of butorphanol, detomidine and 3-hydroxydetomidine at predetermined time points were measured by liquid chromatography–tandem mass spectrometry (LC-MS/MS). The intravenous pharmacokinetics of butorphanol dosed individually compared with co-administration with detomidine had approximately a twofold larger clearance (646 ± 137 vs. 380 ± 86 ml hr−1 kg−1) but similar terminal half-life (5.21 ± 1.56 vs. 5.43 ± 0.44 hr). Pseudo-steady-state urine to plasma butorphanol concentration ratios were 730 and 560, respectively. The intravenous pharmacokinetics of detomidine dosed as a single administration compared with co-administration with butorphanol had similar clearance (3,278 ± 1,412 vs. 2,519 ± 630 ml hr−1 kg−1) but a slightly shorter terminal half-life (0.57 ± 0.06 vs. 0.70 ± 0.11 hr). Pseudo-steady-state urine to plasma detomidine concentration ratios are 4 and 8, respectively. The 3-hydroxy metabolite of detomidine was detected for at least 35 hr in urine from both the single and co-administrations. Detection times of 72 and 48 hr are recommended for the control of butorphanol and detomidine, respectively, in horseracing and equestrian competitions. 相似文献