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排序方式: 共有6521条查询结果,搜索用时 15 毫秒
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Patrick M. McCue DVM PhD Jill Thayer DVM Edward L. Squires PhD Steven P. Brinsko DVM PhD Dirk K. Vanderwall DVM PhD 《Journal of Equine Veterinary Science》1998,18(12):832-834
Spontaneous development of identical or monozygotic twins is a rare event in the horse. Monozygotic twins develop after division of a single embryo. This report documents three cases in which twin embryos developed following surgical transfer of a single morula stage embryo into the uterus of a synchronized recipient mare. 相似文献
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Barbara Page DVM 《Journal of Equine Veterinary Science》1998,18(12):784-785
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B.D. Nielsen PhD G.D. Potter PhD L.W. Greene PhD E.L. Morris DVM M. Murray-Gerzik MS W.B. Smith PhD M.T. Martin DVM 《Journal of Equine Veterinary Science》1998,18(3):190-200
This study was conducted to determine physiologic responses reflective of bone metabolism during the onset of training and to relate those responses to the mineral requirements of young racehorses. Ten previously untrained Quarter Horse geldings were put into race training. They were fed a diet balanced to meet NRC recommendations for young horses in training. Feed, feces and urine were collected, weighed and analyzed over the experiment to determine mineral balance. Radiographs were taken of the left front leg to determine mineral content of a cross-sectional area of the third metacarpal. Blood samples were taken to determine osteocalcin, parathyroid hormone, 25-hydroxyvitamin D, Ca and inorganic P concentrations. Horses were gentled to ride, trained to gallop on the track and maintained in training for four 28-day periods. Blood serum was collected every 14 day, while radiographs and 72-hr total collections of urine and feces were taken every 28 d. Radiographs demonstrated that mineral content was lowest at day 56 in the dorsal, palmar and medial cortices of the third metacarpal. Urinary Ca declined dramatically from day 0 to day 28, then remained constant to day 56, before decreasing at day 84. Fecal Ca peaked at day 28 and remained elevated above day 0 amounts until day 112. calcium retention was negative at day 0, became slightly positive by day 28 and increased through day 112. Phosphorus and Mg balance remained relatively unchanged throughout the duration of the study. This study demon-strated changes in the mineral content of the third metacarpal and Ca balance during early training and suggests that further studies be performed. 相似文献
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Valerie F. Samii DVM David S. Biller DVM Philip D. Koblik DVM MS 《Veterinary radiology & ultrasound》1999,40(5):486-490
Magnetic resonance images of two adult domestic short-haired cats were obtained with a whole body scanner. Images of the abdomen were compared with cross-sectional anatomy cadaver specimens from the same two cats. Anatomic structures were first identified on the cadaver specimens with the aid of anatomy texts and references and were then identified and labeled on the magnetic resonance images. Results from this project provide an atlas of normal cross-sectional MRI anatomy of the feline abdomen. 相似文献