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21.
Meenakshi Mukherjee Jeryl C. Jones Ida Holásková Raymond Raylman Jean Meade 《Veterinary radiology & ultrasound》2017,58(5):565-580
Deep phenotyping tools for characterizing preclinical morphological conditions are important for supporting genetic research studies. Objectives of this retrospective, cross‐sectional, methods comparison study were to describe and compare qualitative and quantitative deep phenotypic characteristics of lumbosacral stenosis in Labrador retrievers using computed tomography (CT). Lumbosacral CT scans and medical records were retrieved from data archives at three veterinary hospitals. Using previously published qualitative CT diagnostic criteria, a board‐certified veterinary radiologist assigned dogs as either lumbosacral stenosis positive or lumbosacral stenosis negative at six vertebral locations. A second observer independently measured vertebral canal area, vertebral fat area, and vertebral body area; and calculated ratios of vertebral canal area/vertebral body area and vertebral fat area/vertebral body area (fat area ratio) at all six locations. Twenty‐five dogs were sampled (lumbosacral stenosis negative, 11 dogs; lumbosacral stenosis positive, 14 dogs). Of the six locations, cranial L6 was the most affected by lumbosacral stenosis (33%). Five of six dogs (83%) with clinical signs of lumbosacral pain were lumbosacral stenosis positive at two or more levels. All four quantitative variables were significantly smaller at the cranial aspects of the L6 and L7 vertebral foramina than at the caudal aspects (P < 0.0001). Fat area ratio was a significant predictor of lumbosacral stenosis positive status at all six locations with cranial L6 having the greatest predictive value (R2 = 0.43) and range of predictive probability (25–90%). Findings from the current study supported the use of CT as a deep phenotyping tool for future research studies of lumbosacral stenosis in Labrador retrievers. 相似文献
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M D Lindemann R J Meade S G Cornelius H E Hanke K P Miller J W Rust 《Journal of animal science》1983,56(4):853-857
In a series of five trials, 680 crossbred pigs were fed isolysine diets in which high protein (13.8 to 16.0%) oats constituted 0, 20, 40 or 60% of the cereal portion. There was a linear depression in average daily gain (P less than .001) and average daily feed intake (P less than .005) with increasing level of oats, but feed/gain was unaffected (P less than .05) during the growing period from 22 to 46 kg. There were no significant differences in average daily gain during the finishing period from 46 to 102 kg; however, feed/gain increased linearly (P less than .01) with increasing level of oats in the diet. Increases in the percentage of oats in the cereal portion of the diet resulted in a linear (P less than .01) decrease in average daily gain and an increase (P less than .01) in feed/gain for the entire feeding period. We conclude that high protein-high lysine oats of the quality used in these trials can be included at up to 20% of the cereal portion of the diet without greatly affecting performance. 相似文献
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The absorption of glycine and proline through the mid-intestines of chicks infected with Eimeria acervulina was impaired when the amino acids were presented to the mucosal surface as the dipeptide, glycylproline. 相似文献
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Boylan Malena O’Brien Megan B. Beynon Charlotte Meade Kieran G. 《Veterinary research communications》2020,44(2):83-88
Veterinary Research Communications - The faecal-oral route is a predominant mode of infectious disease transmission and yet the immunology of the bovine oral cavity is poorly understood. The... 相似文献
28.
Appreciable Amounts Of suspended matter (> 1.0 milligram per liter) in surface waters are restricted to within a few kilometers of the Atlantic coast. Particles that escape estuaries or are discharged by rivers into the shelf region tend to travel longshoreward rather than seaward. Suspended matter farther offshore, chiefly amorphous organic particles, totals 0.1 milligram per liter or less. Soot, fly ash, processed cellulose, and other pollutants are widespread. 相似文献
29.
Silver PG Beck SL Wallace TC Meade C Myers SC James DE Kuehnel R 《Science (New York, N.Y.)》1995,268(5207):69-73
The M(w) = 8.3 deep (636 kilometers) Bolivian earthquake of 9 June 1994 was the largest deep-focus earthquake ever recorded. Seismic data from permanent stations plus portable instruments in South America show that rupture occurred on a horizontal plane and extended at least 30 by 50 kilometers. Rupture proceeded at 1 to 3 kilometers per second along the down-dip azimuth of the slab and penetrated through more than a third of the slab thickness. This extent is more than three times that expected for a metastable wedge of olivine at the core of the slab, and thus appears to be incompatible with an origin by transformational faulting. These large events may instead represent slip on preserved zones of weakness established in oceanic lithosphere at the Earth's surface. 相似文献
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Measurements of the yield strength of SiO(2) glass to pressures as high as 81 gigapascals at room temperature show that the strength of amorphous silica decreases significantly as it is compressed to denser strctures with higher coordination. Above 27 gigapascals, as the silicon in amorphous SiO(2) is continuously transformed from fourfold to sixfold coordination, the strength of the glass decrases by more than an order of magnitude. These data confirm theoretical predictions that the mechanical properties of polymerized amorphous silicates are sensitive to pressure-induced structural transformations and suggest that the viscosity of silica-rich liquids decreases significantly at high pressures. Such a change in melt rheology could enhance the processes of chemical differentiation with depth in the Earth's mantle. 相似文献