Schiff-Sherrington syndrome in a 7-year-old zebra mare (Equus quagga)

A 7-year-old plains zebra (Equus quagga) mare was presented to the Clinic for Horses, University of Veterinary Medicine Hannover, Foundation, Germany as an emergency. The owner reported that the mare was unable to stand after a suspected traumatic episode at the home yard. The mare was transported in lateral recumbency in a trailer. Clinical examination revealed tachycardia (up to 102 beats/min), tachypnoea (28 breaths/min), mild fever (38.7°C) and clinical dehydration with elastic skin and dry and red mucous membranes. Neurological examination showed paraplegia with complete loss of nociception of the mid-thoracic region and caudal to it. In contrast, examination of the thoracic limbs revealed marked extensor rigidity and hyperaesthesia resulting in an enhanced acute response to minimal touch of the neck and shoulder region. Lateral radiographs of the thoracic vertebral column led to the diagnosis of a complete fracture of the vertebral body of the 7th thoracic (T) vertebra with suspected traumatic compression of the spinal cord. Post-mortem examination confirmed the diagnosis. Gross pathology revealed a complete comminuted fracture of T7 with marked compression of the spinal cord. This is the first report describing the clinical, radiological and pathological findings of a fracture of a thoracic vertebra leading to a Schiff-Sherrington syndrome in a zebra (Equus quagga).     

THE MIXED MODE FRACTURE CRITERION OF BRITTLE ROCK UNDER COMPRESSION-SHEAR STRESS STATE

In this paper the test results of mixed mode fracture of three kinds of brittle rock under two kinds of stress paths are reported. The fracture mechanism and failure patterns of brittle lock under different stress paths are discussed. Theory analysis and test results show that the Compression- Shear fracture criterion of brittle rock can be expressed:     

THE SIZE EFFECT OF THE FRACTURE ENERGY OF CONCRETE TESTED BY THREE POINT BENDING

This paper ainalyses the size effect of the fracture energy of concrete tested bythree point bending. It is shown that positive errors of test results of fracture energy increase,ornegative errors decrease with increasing of the specimen ize. The phenomenon is one of main causesresulting in the size effect of fracture energy.     

A STUDY ON FRACTURE MECHANICS OF BRITTLE MATERIAL WITH PER-CRACKS

In this paper the fracture process of specimen,with single crack, double cracks and triple cracks is observed and analysed. The experimental results show that the fracture process of specimen is different because of the differention of the number, the distance and the type of array of cracks. And the fracture propagation of specimen with triple cracks and double cracks is foundmentally the same.     

Z-形钛合金钢板前路内固定术治疗胸腰椎爆裂性骨折的疗效观察

目的观察Z-形钛合金钢板前路内固度定术对胸腰椎爆裂性骨折患者的临床疗效。方法对60例胸腰段脊柱爆裂性骨折患者进行前方减压、椎体间植骨、Z-形钛钢板内固定,术后卧床3周,3周后戴支架起床活动。结果随访平均12.5个月,术后CT或MR显示椎管内压迫去除,植骨愈合。脊柱后凸Cobb角较术前改善12.7°,无继发脊柱后凸畸形。神经功能较术前有1~2级以上的改善。结论Z-形钛合金钢板前路内固定术对胸腰椎爆裂性骨折减压彻底,固定牢固,不破坏后稳定结构,并能一期重建脊柱系列。     

壮筋补骨丸促进家兔人工骨折愈合的组织学观察

为客观评价壮筋补骨丸促进骨折愈合的作用,选用30只雄性新西兰兔造成右侧桡骨3 mm完全缺损的骨折模型,随机分为模型组、伤科组和壮筋组,分别给予生理盐水、伤科接骨片和壮筋补骨丸灌胃,连续4周.各组动物每周处死3只,取样进行HE染色、Masson染色和PAS染色观察,并于术后28 d取右侧桡骨(骨折骨)进行扫描电镜观察.结果表明,壮筋组较模型组及伤科组提前1周PAS和Masson染色呈阳性,于2周后观察到胶原纤维大量出现,成骨过程明显快于模型组.电镜观察显示模型组术后4周骨痂生长,胶原纤维交错排列,未出现成熟的骨细胞,而伤科组及壮筋组术后4周胶原纤维平行簇状排列,出现了板质骨和骨细胞,与模型组比较差异明显,表明壮筋补骨丸能促进新西兰兔骨折愈合.     

疲劳/蠕变交互作用下竹木复合层合板断裂损伤研究

该文研究了在疲劳/蠕变交互作用下竹木复合层合板的断裂损伤行为.结果表明,在交变载荷最大值为竹木复合层合板破坏载荷的75%时,其疲劳/蠕变断裂曲线为三段式曲线;在交变载荷最大值为破坏载荷的55%时,6h内其疲劳/蠕变曲线为两段式曲线.随着蠕变时间的增加,层合板的断裂寿命降低.在交变载荷最大值为破坏载荷的75%时,蠕变时间为300s时,层合板的疲劳/蠕变负交互损伤程度大于蠕变时间为180s的.疲劳/蠕变交互作用下层合板的破坏形式主要为纤维撕裂、界面剪切破坏和层间开裂3种形式的综合表现.     

高强度管道钢氢致开裂门槛应力测定

采用恒载荷和慢应变速率动态拉实验方法。测定了X80管道钢在不同充氢条件下的氢致开裂门槛应力和断裂应力，测试结果表明，X80管道钢在0．5mol/L H2SO4 0.25g/L As2O3溶液中充氢时，试样中可扩散氢浓度（C0）和充气电流的方根（√i）呈线性关系，不同充氢条件下慢应变速率拉伸时断裂应力均随氢浓度升高而下降，恒载荷下氢致滞后断裂门槛应力随氢浓度的对数而呈线性下降。