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排序方式: 共有509条查询结果,搜索用时 31 毫秒
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Isabelle Ann Kagan PhD Brett H. Kirch DVM PhD Craig D. Thatcher DVM PhD Chris D. Teutsch PhD François Elvinger Dr Med Vet PhD Dare M. Shepherd BS Scott Pleasant DVM MS 《Journal of Equine Veterinary Science》2011,31(9):521-529
Seasonal and diurnal patterns of sugar accumulation in bermudagrass (Cynodon dactylon) pastures were monitored to evaluate risk factors for pasture-associated laminitis of ponies and horses. Bermudagrass was collected from four plots in the morning and afternoon on a weekly basis, from mid-July until late August. Tissue was air-dried to simulate hay, or frozen to retain the sugar profiles of fresh pasture. Samples were analyzed colorimetrically for total water-soluble and ethanol-soluble carbohydrates, and electrochemically for starch. In addition, sugars were separated and quantified by high-performance liquid chromatography coupled to pulsed amperometric detection. The dominant sugars in extracts were glucose, fructose, and sucrose. Some minor peaks, corresponding to tri- and tetrasaccharides, were also detected in some extracts. Starch increased over time in fresh and dried tissue, and concentrations varied diurnally in fresh, but not in dried tissue (P = .021). Sucrose in dried tissue decreased and then increased, with higher concentrations than in fresh tissue on all sampling dates (P = .024). Glucose and fructose exhibited diurnal variation on one and two dates, respectively (P = .034 and .0028, respectively). These results reveal trends in carbohydrate concentrations and profiles that may help to evaluate the likelihood of equine laminitis outbreaks on bermudagrass. 相似文献
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Sturgill TL Strong D Rashid C Betancourt A Horohov DW 《Veterinary immunology and immunopathology》2011,141(1-2):124-127
Production of the Th1 cytokine interferon gamma (IFNγ) is associated with resistance to intracellular pathogens, including Rhodococcus equi. While neonatal foals are initially deficient in IFNγ production, expression of this cytokine increases throughout their first year of life. This is presumably the result of stimulation by environmental antigens including pathogen associated molecular patterns (PAMPS) signaling through toll-like receptors (TLR). This increased expression of IFNγ is likewise associated with an age-related resistance to R. equi infection. While immunostimulants containing PAMPS have been administered to adult horses in an attempt to modify their immune response, the effect of these materials on IFNγ expression in foals is unknown. The main objective of this study was to determine the effect of administering a commercial immunomostimulant EqStim? (Propionibacterium acnes) on IFNγ production measured using intracellular staining (IFNγ) and RT-PCR. 相似文献
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Neeru Narula Prof. Dr BS Saharan Vivek Kumar Ranjana Bhatia LK Bishnoi BPS Lather 《Archives of Agronomy and Soil Science》2013,59(1):69-77
High nitrogen fixing, phosphate solubilizing, phytohormones producing isolates of Azotobacter, Azospirillum, Acetobacter and Pseudomonas were used as inoculants for cotton. Important cultures were selected on the basis of their effect on root/shoot length and chemotactic behaviour. Selected bioinoculants were earlier tested for their beneficial properties like nitrogen fixation (ARA), ammonia excretion, IAA production etc. These bio-inoculants were further tested for phosphate solubilization property. Various chosen strains were tested with Desi (HD 123) and American (H 1098) cotton under field conditions (as for wheat). Plant height and boll weight were determined at the time of harvesting whereas survival rate of inoculated bacteria was determined after 30, 80 and 130 days respectively. In the year 2000–01, on the basis of boll number and boll weight plant?1 AVK 51 (36; 76.2?g plant?1), HT 57 (27; 56.9?g plant?1), AC18 (33; 61.5?g plant?1), Ala 27 (36; 61.4?g plant?1) and Pseudomonas (34; 71.3?g plant?1) were identified as significant both for American and desi cotton varieties. Highest survival rate was observed with Mac 68 (33.4 × 105) followed by HT54 (31.5 × 105) after 30 days of sowing, which decreased after 80 days and remained constant up to 130 days. This trend was observed with all the cultures. Similar results were observed in 2001–02. 25?kg ha?1 N saving was observed with A. chroococcum (AVK51) bioinoculant for cotton crop. 相似文献
97.
Rebecca L. Stepien DVM MS Keith G. Benson DVM Lisa J. Wenholz BS 《Veterinary radiology & ultrasound》2000,41(5):452-456
M-mode and Doppler echocardiographic values were obtained from 30 normal adult ferrets (14 neutered females, 13 neutered males, 3 intact males) sedated with an intramuscular combination of ketamine hydrochloride and midazolam. Routine M-mode measurements of the left and right ventricle, left atrium (LA) and aorta (AO) and Doppler measurements of aortic and pulmonic outflow, and mitral inflow were recorded. The following values were calculated: LA:AO diameter, ratio of peak E: peak A wave velocity (E:A ratio) for mitral inflow, and stroke volume (SV), cardiac output (CO) and cardiac index (CI) for both pulmonary and aortic outflow tracts. Maximal aortic velocities (AOmax) and velocity-time integral values (AO VTI) were significantly less than corresponding pulmonary outflow tract values (PAmax, PA VTI) but there was no difference in calculated values for SV, CO or CI. Calculated CO values were in the range expected based on the size of the species. Difficulties in aligning the aortic outflow tract for Doppler imaging may make pulmonary outflow Doppler values more consistent for use in estimating volume flow in ferrets. 相似文献
98.
Takayoshi Miyabayashi BVS MS PhD Mark Smith BS RT MS † Yoshihiro Tsuruno BVSc 《Veterinary radiology & ultrasound》2000,41(4):308-312
Various magnetic resonance (MR) imaging techniques have been used to assess lumbar spinal abnormalities in people. Four, young adult, clinically normal dogs were used to compare images of the spinal cord acquired using conventional spin-echo and rapid acquisition relaxation-enhanced (RARE), commonly called fast spin-echo (FSE), magnetic resonance imaging techniques. Lateral myelograms were made as an anatomic control. The T2-weighted FSE technique was characterized by better image quality than the T2-weighted conventional spin-echo technique. The short acquisition time with the FSE technique allowed increases in the matrix size and number of excitations, thus improving resolution and signal-to-noise ratio. In canine lumbar spinal MR imaging, use of a FSE technique is recommended to reduce the overall time for imaging and to improve image quality. 相似文献
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