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141.
Magnetic resonance imaging susceptibility artifact due to pigmented intraorbital silicone prosthesis
D. Dustin Dees Amy M. Knollinger Jeffery P. Simmons Ravi Seshadri Nicole E. MacLaren 《Veterinary ophthalmology》2012,15(6):386-390
Magnetic resonance imaging (MRI) findings of two cases with intracranial disease and pigmented intraorbital prosthetics are presented. A brown prosthetic (Case 1) caused a significant magnetic susceptibility artifact, which necessitated removal to properly image the brain. The artifact observed on MRI images is likely due to ferromagnetic pigments used for coloring. A black prosthetic (Case 2) caused no imaging artifact. The carbon‐based pigments used to color the black prosthetic implant do not appear to cause imaging artifact. The pigments currently used to color the brown pigmented orbital prostheses cause significant magnetic susceptibility artifact and may require removal to evaluate the brain and surrounding structures completely. 相似文献
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湖羊是世界上稀有的绵羊地方品种,以多胎、早熟、早期生长发育快、宜舍饲等优良性能而著名。为系统了解湖羊生长发育的基本规律,更好地开发利用湖羊这一优良地方品种资源,本研究以3,6,12和24月龄湖羊公羊为对象,每个时间点随机选择6只,共24只,测定其体重、组织器官及消化道各个部分重量、肠道长度及肉品质相关参数。结果表明,3~6月龄湖羊生长速率最快,6月龄之后逐渐降低;3~6月龄之间心、肝、脾、肺、肾、头蹄和皮的增长强度随着日龄的增大而增长,除头、蹄、皮外,其他内脏器官的生长强度逐渐降低,12月龄之后趋于稳定;头、蹄、皮的生长在6月龄之后趋于稳定,仍然保持较高的生长强度;瘤胃的生长强度始终大于体重生长强度,小肠的生长始终小于体重,而除直肠外,大肠的生长强度与体重相近。6月龄湖羊公羔与12月龄相比屠宰率、眼肌面积无显著差异,而6月龄湖羊公羔背膘厚极显著增高,随着年龄的增长肉色逐渐变暗。综合以上各项指标认为,本试验条件下,6月龄为肥羔生产最佳屠宰日龄。 相似文献
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AI Peña M Barrio JJ Becerra LA Quintela PG Herradón 《Reproduction in domestic animals》2007,42(5):471-478
A 4-year-old Basque Shepherd male dog was presented for breeding soundness evaluation after the dog failed to impregnate the three bitches he had mated. Clinical examination showed no anomaly of the reproductive system. Semen evaluation showed normal sperm count (640 x 10(6)), 80% had progressively motile spermatozoa, and 96% had morphologically abnormal sperm of which 84% had proximal cytoplasmic droplet and 12% had proximal droplet plus other anomaly. A zona pellucida-binding assay, using canine oocytes derived from frozen-thawed ovaries, was performed in order to investigate the zona-binding ability of dog spermatozoa with proximal cytoplasmic droplets. For the zona pellucida-binding assay, ovaries were thawed and minced in phosphate-buffered saline + 0.4% bovine serum albumin, the oocytes recovered were divided into two groups of 35-40 oocytes to be, respectively, used with the infertile dog and with a control fertile dog. Spermatozoa were capacitated in Canine Capacitating Medium (CCM) at 38.5 degrees C and 5% CO(2) in air for 2 h before oocyte insemination. Groups of five to six oocytes placed in 45 microl droplets of CCM were incubated for 1 h. Afterwards, 5 microl of CCM containing 25,000 spermatozoa were added to each droplet and co-incubated for 2 h before fixation and evaluation of the complexes. After oocyte insemination, sperm motility and viability were evaluated: the sample from the infertile dog had 85% sperm motility with fast and linear progressive movement, and sperm viability of 92%. The sample from the control dog showed 40% sperm motility with fast and highly curvilinear and erratic movement, high degree of sperm agglutination and sperm viability of 32%. For the infertile dog the mean number of bound spermatozoa/oocyte was 0.33 whereas for the control dog it was 1.80. It was concluded that dog sperm with proximal cytoplasmic droplets seem to lack normal capacitating ability in vitro, and consequently, they may have reduced capacity to bind to the zona pellucida of canine oocytes. 相似文献
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本试验旨在探究不同蛋白质水平补饲料对3月龄早期断奶犊牦牛生产性能、血液指标和胃肠道发育的影响。选取3月龄(90±5)日龄]健康大通母犊牦牛48头,随机分为4组,每组4个重复,每个重复3头。对照组犊牛全放牧,试验组犊牛在放牧基础上分别补饲不同蛋白质水平(粗蛋白质水平分别17%、18%、19%)的3种等能量(增重净能5.6 MJ/kg)饲粮。预试期7 d,正试期60 d。结果表明:1)与对照组相比,补饲能够显著提高犊牦牛的平均日增重,17%、18%和19%补饲组分别提高了28.87%、47.47%和28.61%(P0.05)。2)与对照组相比,补饲显著提高了血清尿素氮浓度(P0.05),17%、18%和19%补饲组分别增加了10.57%、16.64%、21.84%(P0.05)。3)与对照组组相比,补饲料粗蛋白质水平为18%时,显著提高了瘤胃和大肠的绝对重量和相对重量(P0.05),显著提高了十二指肠、盲肠、结肠的绒毛高度以及十二指肠和盲肠的绒毛高度/隐窝深度(P0.05)。因此,补饲能够提高早期断奶母犊牦牛生产性能和促进胃肠道发育,早期断奶母犊牦牛的补饲料的适宜粗蛋白质水为18%。 相似文献
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