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71.
J M Mastro M G Lewis L E Mathes R Sharpee M J Tarr R G Olsen 《Veterinary immunology and immunopathology》1986,11(3):205-213
An effective subunit vaccine against feline leukemia virus infection and related diseases has been developed. The source of the vaccine immunogen is feline retrovirus persistently infected cells that continuously synthesize and shed virus polypeptides. Western blot analysis identifies FeLV-gp70, p27, p15, p12, and p10 in the subunit vaccine preparation. Cats immunized with the vaccine developed antibodies to a 70,000 MW protein of the vaccine that seems to be distinct from, but related to the FeLV-gp70 polypeptide. 相似文献
72.
Tissue DT Lewis JD Wullschleger SD Amthor JS Griffin KL Anderson OR 《Tree physiology》2002,22(15-16):1157-1166
Trees exposed to elevated CO2 partial pressure ([CO2]) generally show increased rates of photosynthesis and growth, but effects on leaf respiration are more variable. The causes of this variable response are unresolved. We grew 12-year-old sweetgum trees (Liquidambar styraciflua L.) in a Free-Air CO2 Enrichment (FACE) facility in ambient [CO2] (37/44 Pa daytime/nighttime) and elevated [CO2] (57/65 Pa daytime/nighttime) in native soil at Oak Ridge National Environmental Research Park. Nighttime respiration (R(N)) was measured on leaves in the upper and lower canopy in the second (1999) and third (2000) growing seasons of CO2 fumigation. Leaf respiration in the light (R(L)) was estimated by the technique of Brooks and Farquhar (1985) in the upper canopy during the third growing season. There were no significant short-term effects of elevated [CO2] on R(N) or long-term effects on R(N) or R(L), when expressed on an area, mass or nitrogen (N) basis. Upper-canopy leaves had 54% higher R(N) (area basis) than lower-canopy leaves, but this relationship was unaffected by CO2 growth treatment. In August 2000, R(L) was about 40% of R(N) in the upper canopy. Elevated [CO(2)] significantly increased the number of leaf mitochondria (62%), leaf mass per unit area (LMA; 9%), and leaf starch (31%) compared with leaves in ambient [CO(2)]. Upper-canopy leaves had a significantly higher number of mitochondria (73%), N (53%), LMA (38%), sugar (117%) and starch (23%) than lower-canopy leaves. Growth in elevated [CO2] did not affect the relationships (i.e., intercept and slope) between R(N) and the measured leaf characteristics. Although no factor explained more than 45% of the variation in R(N), leaf N and LMA were the best predictors for R(N). Therefore, the response of RN to CO2 treatment and canopy position was largely dependent on the magnitude of the effect of elevated [CO2] or canopy position on these characteristics. Because elevated [CO2] had little or no effect on N or LMA, there was no effect on R(N). Canopy position had large effects on these leaf characteristics, however, such that upper-canopy leaves exhibited higher R(N) than lower-canopy leaves. We conclude that elevated [CO2] does not directly impact leaf respiration in sweetgum and that barring changes in leaf nitrogen or leaf chemical composition, long-term effects of elevated [CO2] on respiration in this species will be minimal. 相似文献
73.
本论文研究了饲料加工的两个关键参数(调质温度和时间)对育肥猪颗粒饲料淀粉糊化度和维生素沉积的影响。日粮配方为含30%干酒糟及其可溶物的玉米-豆粕型基础日粮。整个试验中配方保持不变。本试验采用2×3双因子设计,调质温度分别为77℃和88℃,调质时间分别15秒、30秒和60秒。此外,本试验还设置一个对照组,对照组饲料不采用调质制粒工艺,而是采用粉料饲喂。因此,本试验共有7个处理组。采集调质后制粒前(热干粉)、制粒后冷却前(热制粒)、以及制粒冷却后(冷制粒)的样品,并分析这三种样品的总淀粉率、淀粉糊化 相似文献
74.
Perception of Teaching and Assessing Technical Proficiency in American College of Veterinary Surgeons Small Animal Surgery Residency Programs
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75.
76.
Cryopreservation of Piau‐Breed Wild Boar Sperm: Assessment of Cooling Curves and Centrifugation Regimes
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HH Shiomi RO Pinho DMA Lima JB Siqueira MCR Santos EV Costa PS Lopes SEF Guimarães JD Guimarães 《Reproduction in domestic animals》2015,50(4):545-553
This study aimed to assess the effects of different cooling curves and centrifugation regimes used in cryopreservation protocols on the post‐thaw viability of Piau‐breed wild boar (Sus scrofa) sperm using in vitro assessment tests. Two centrifugations (800 g for 10 min and 2400 g for 3 min) and two cooling curves (conventional cooling using nitrogen vapour – freezing 1 and automated cooling using a programmed freezing machine – freezing 2) were tested. Therefore, the treatments were divided into M3 – centrifugation at 2400 g for 3 min and freezing 2; M10 – centrifugation at 800 g for 10 min and freezing 2; R3 – centrifugation at 2400 g for 3 min and freezing 1; and R10 – centrifugation at 800 g for 10 min and freezing 1. No significant differences (p > 0.05) between treatments occurred post‐thawing regarding the total sperm motility means recorded. The mean values of the different treatments were not different from each other regarding the supravital staining (SV), hypo‐osmotic test (HO), sperm–egg binding assay or sperm morphology. This study showed that both the cooling curve and the centrifugation regime affected the quality of post‐thaw sperm, and centrifugation for shorter times and cooling curves using automated cooling are the most suitable for minimizing sperm injury. 相似文献
77.
78.
Bryszewska MA Ambroziak W Langford NJ Baxter MJ Colyer A Lewis DJ 《Plant foods for human nutrition (Dordrecht, Netherlands)》2007,62(3):121-126
The potential of selenium-enriched rye/wheat sourdough bread as a route for supplementing dietary selenium intakes is reported.
In addition to their normal diets, 24 female volunteers (24 to 25 years old) were fed either selenium-enriched bread or non-enriched
bread each day (68.02 and 0.84 μg selenium day−1 respectively) for 4 weeks. The chemical form of the selenium in the bread had been characterised using HPLC-ICP-MS, which
showed that 42% of the extractable selenium was present as selenomethionine. Plasma selenium levels and plasma platelet glutathione
peroxidase (GPx1) activity were measured in the volunteers’ blood over a 6-week period. A statistically significant difference
(p = 0.001) was observed in the mean percentage change data, calculated from the plasma selenium level measurements for the
enriched and control group, over the duration of the study. A comparable difference was not observed for the platelet GPx1
activity (p = 0.756), over the same period. Two weeks after cessation of the feeding stage, i.e., at t = 6 weeks, the mean percentage change value for the selenium plasma levels in the enriched group was still significantly
elevated, suggesting that the absorbed selenium had been incorporated into the body’s selenium reserves, and was then being
slowly released back into the volunteers’ blood. 相似文献
79.
Georgina Limon Elisa G. Lewis Yu-Mei Chang Hugo Ruiz Maria Elba Balanza Javier Guitian 《Preventive veterinary medicine》2014
Livestock disease surveillance is particularly challenging in resource-scarce settings, where disease events are often unreported. Surveillance performance is determined as much by the quantifiable biological attributes of the disease, as it is by motivations and barriers perceived by livestock keepers for disease reporting. Mixed methods designs, which integrate the collection, analysis and interpretation of qualitative and quantitative data in a single study, are increasingly used across different disciplines. These designs allow for a deeper exploration of the topic under investigation, than can be achieved by either approach alone. 相似文献
80.
The Potential for Replacement of Live Feeds in Larval Culture 总被引:6,自引:0,他引:6
David A. Jones Mohd. Salleh Kamarudin Lewis Le Vay 《Journal of the World Aquaculture Society》1993,24(2):199-210