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排序方式: 共有468条查询结果,搜索用时 15 毫秒
1.
Sean G. Sanders DVM Russell L. Tucker DVM Rodney S. Bagley DVM Patrick R. Gavin DVM PhD 《Veterinary radiology & ultrasound》2001,42(4):291-296
Magnetic resonance imaging (MR) was used to make a diagnosis of equine nigropallidal encephalomalacia in a horse. Equine nigropallidal encephalomalacia is a neurodegenerative disease that has many characteristics with Parkinson-like diseases in humans. Historically, horses were euthanized based on clinical signs and exposure to the toxic weed, yellow star thistle (Centaurea solstitialis). Previously, the disease has only been confirmed on necropsy. MR imaging can provide accurate and sensitive visualization of typical lesions seen in the brain of horses affected with equine nigropallidal encephalomalacia. Lesions were seen on T1-weighted, T2-weighted and proton density images. There was no contrast enhancement following Gd-DTPA administration. Lesions seen on MR were confirmed at necropsy. Using MR to confirm a diagnosis of equine nigropallidal encephalomalacia will prevent unnecessary suffering of horses and expense to owners that would otherwise incur, while further diagnostics are performed. 相似文献
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Chloroform-methanol (2:1 v/v), absolute methanol, and 90% acetone were evaluated for their effectiveness as extractants of chlorophyll a from samples of phytoplankton communities collected from catfish ponds. Chloroform-methanol consistently extracted more chlorophyll a than either 90% acetone or methanol. Precision for the methanol extraction was also unacceptably low, with an average coefficient of variation of 17%. Average coefficients of variation for the chloroform-methanol and 90% acetone extraction procedures were 6 and 5%, respectively. Filtered samples should be steeped in chloroform-methanol for at least 4 h to obtain maximum chlorophyll extraction, and the addition of MgCO3 to the extractant as a buffer is not necessary. 相似文献
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T. Dale I. Hannay M. R. Bedford G. A. Tucker J. M. Brameld T. Parr 《British poultry science》2020,61(4):471-481
ABSTRACT 1. This study quantified xylanase-induced changes in soluble monosaccharides, xylooligosaccharides (XOS) and volatile fatty acid (VFA) contents of the different sections of the gastrointestinal tract (GIT) and whether these were related to altered bird performance. 2. An in vitro digestion of the wheat-based diet was carried out with the xylanase (Econase XT at 16,000BXU/kg diet) to compare the in vitro and in vivo generation of these XOS and monosaccharides. For the in vivo study, 80 male Ross 508 b roiler chicks were split into two groups fed a wheat-based diet with or without Econase XT (16,000BXU/kg diet) for 21 days. 3. There were no effects of Econase XT inclusion on growth performance characteristics, likely a result of the high-quality wheat diet, the corresponding high performance of the control group (FCR average of 1.45 in controls) and the relatively young age of the birds (from four to 26 days of age). 4. Econase XT supplementation increased the xylotetraose (X4) content in the colon (P = 0.046, enzyme x GIT section interaction) and the xylose contents in the colon and caeca (P < 0.001, enzyme x GIT section interaction). 5. The trend for increased acetate production in the caeca of Econase XT treated birds (P = 0.062) suggested that the XOS generated were subsequently fermented in the caeca, potentially impacting upon the types of microbiota present. 6. The present study suggested that wheat arabinoxylan degradation was enhanced by xylanase supplementation, which may have increased the production of beneficial volatile fatty acids (VFA) in the caeca, and thereby potentially modulated the caecal microbiome, but without affecting bird performance at this early age. 相似文献
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Talegawkar SA Johnson EJ Carithers TC Taylor HA Bogle ML Tucker KL 《Public health nutrition》2008,11(10):989-997
OBJECTIVES: Intake and status of carotenoids have been associated with chronic disease. The objectives of this study were to examine the association between carotenoid intakes as measured by two regional food-frequency questionnaires (FFQs) and their corresponding measures in serum, and to report on dietary food sources of carotenoids in Jackson Heart Study (JHS) participants. DESIGN: Cross-sectional analysis of data for 402 African American men and women participating in the Diet and Physical Activity Sub-Study (DPASS) of the JHS. RESULTS: Mean serum carotenoid concentrations and intakes in this population were comparable to those reported for the general US population. After adjustment for covariates, correlations between serum and dietary measures of each carotenoid, for the average of the recalls (deattenuated), the short FFQ and the long FFQ, respectively, were: 035 and 0-carotene; 026 and 0-carotene; 017 and 0-carotene; 034 and 0-cryptoxanthin; 015 and 037, 014 for lycopene. Major dietary sources of -carotene and lutein plus zeaxanthin, mustard, turnip and collard greens; of beta-cryptoxanthin, orange juice; and of lycopene, tomato juice. CONCLUSIONS: On average, carotenoid intakes and serum concentrations are not lower in this southern African American population than the general US population. The two regional FFQs developed for a southern US population and used as dietary assessment tools in the JHS appear to provide reasonably valid information for most of these carotenoids. 相似文献
7.
Claude E. Boyd Craig S. Tucker Benjaporn Somridhivej 《Journal of the World Aquaculture Society》2016,47(1):6-41
Total alkalinity and total hardness are familiar variables in aquatic animal production. Aquaculturists—both scientists and practitioners alike—have some understanding of the two variables and of methods for adjusting their concentrations. The chemistry and the biological effects of alkalinity and hardness, however, are more complex than generally realized or depicted in the aquaculture literature. Moreover, the discussions of alkalinity and hardness—alkalinity in particular—found in water chemistry texts are presented in a rigorous manner and without explanation of how the two variables relate to aquaculture. This review provides a thorough but less rigorous discussion of alkalinity and hardness specifically oriented toward aquaculture. Alkalinity and hardness are defined, their sources identified, and analytical methods explained. This is followed by a discussion of the roles of the two variables in aquaculture, including their relationships with carbon dioxide, pH, atmospheric pollution, ammonia, and other inorganic nitrogen compounds, phytoplankton communities, trace metals, animal physiology, and clay turbidity. Liming and other practices to manage alkalinity and hardness are explained. Changes in alkalinity and hardness concentrations that occur over time in aquaculture systems are discussed. Emphasis is placed on interactions among alkalinity, hardness, water quality, and aquacultural production. 相似文献
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