Colles骨折手法整复后竹夹板固定与石膏固定的疗效比较

目的 通过随访对Colles骨折手法整复后竹夹板固定与石膏固定的疗效进行比较,确定Colles骨折手法整复后的有效治疗方案。方法 将120例Colles 骨折患者按随机数字表法随机分为竹夹板外固定组60例及石膏外固定组60例,骨折手法整复成功后,按照组别分别给予竹夹板固定及石膏固定治疗,外固定拆除后均给予中药熏洗1个月,6个月后进行随访,并按照Gartland and Werley 腕关节评分比较两组骨折患者的腕关节评分,以评价疗效。结果 竹夹板固定组优良率为83.3%,优于石膏固定组的56.7%（P<0.01）。结论 Colles骨折手法整复后竹夹板固定的疗效优于石膏固定。     

INCOMPLETE OSSIFICATION OF THE HUMERAL CONDYLE IN VIETNAMESE POT-BELLIED PIGS

The purpose of this study was to evaluate the occurrence of humeral condylar fractures in Vietnamese pot-bellied pigs and to postulate a possible predisposing cause for these fractures. Thirteen Vietnamese pot-bellied pigs (Group A) were evaluated over an eight year period (1990-1998), each with a history of either a unilateral or bilateral forelimb lameness. The cause of lameness was localized to the elbow region. Of the thirteen pigs, twenty-one elbows were evaluated radiographically. Pigs ranged in age from six months to four years old. All pigs over the age of seven months showed radiographic evidence of elbow degenerative joint disease. Fractures involving the medial aspect of the humeral condyle were identified in 8/21 studies (38%). A well-defined linear intracondylar articular lucency was identified in 7/21 studies (33%) on the craniocaudal projection. The site of this lucency corresponded to the location of the articular component of the fractures seen involving the humeral condyle. The elbows of five pot-bellied pigs with no known history of forelimb lameness or trauma (Group B) were evaluated radiographically following euthanasia. All five pigs were of unknown age and gender. An intracondylar vertical linear lucency was identified bilaterally in three pigs (60%). Concurrent degenerative joint disease was present in all instances. The remaining two pigs were radiographically normal. Computed tomography of the elbows was performed in one affected pig from Group B. The radiographic findings in this pig were verified. Histopathology of the right elbow of this affected pig was diagnostic for incomplete endochondral ossification of the humeral condyle. A similar condition involving the humeral condyle has been previously described in Cocker and Brittany Spaniels. These canine breeds also have a high incidence of humeral condylar fractures. It is postulated that Vietnamese pot-bellied pigs are similarly prone to humeral condylar fractures, even in the absence of known trauma, due to incomplete ossification of the humeral condyle.     

反拱水垫塘全拱圈3个底板块运动特性的研究

【目的】揭示反拱底板局部稳定和失稳破坏的机理。【方法】结合溪落渡水电站工程,制作了水垫塘精细物理模型,采用先进的模拟方法和测量手段,研究了在底板块止水完全破坏、锚筋失效,其四周及底部完全贯通的情况下,反拱水垫塘拱圈3个活动底板块的运动特性。【结果】反拱底板块振动的优势频率为0.001~0.1 Hz,沿程(x)划分为上下游强振区和冲击弱振区,在x=(-0.30~0.60)m底板块易失稳。【结论】底板块为低频窄带振动,不会发生共振破坏和材料的疲劳破坏。由于底板块形成了长期和局部拱作用,使拱圈保持稳定。     

火灾后预应力混凝土连续板力学性能试验与分析

完成了7块火灾后两跨无黏结预应力混凝土单向连续板受力性能试验.基于试验结果,拟合出火灾后预应力混凝土连续板中无黏结筋剩余应力、极限应力的计算公式,提出了火灾后预应力混凝土连续板正截面承载力计算公式.根据火灾下温度场分布沿板厚方向将截面分条带,引入火灾后钢筋、混凝土本构关系,基于截面轴力、弯矩平衡,获得了火灾下预应力混凝土板任意截面的弯矩-曲率关系全曲线.基于支座变形协调方程,可用割线刚度法对支座反力进行迭代求解,计算板在外荷载(曲率荷载)与支座反力共同作用下的弯矩、挠度和支座位移,进而对截面曲率积分可求得连续板的变形.试验结果表明:初始有效应力越高、受火时间越长,火灾后连续板预应力钢丝应力损失越严重;保护层厚度越小、受火时间越长、荷载水平越大,火灾后板跨中截面承载力降低幅度越大;受火时间越长、荷载水平越大,板中支座截面承载力降低幅度越大.     

现浇楼板在设计和施工中应注意的问题

在设计和施工中,随着新材料、新工艺、新设备、新方法的应用,加快了设计和施工进度,提高了工程质量,但同时也产生了一些新问题,本文阐述了现浇楼板在设计和施工中应注意的问题及应采取的措施和方法。     

浅谈公路桥涵台背回填施工质量控制

本文作者结合工程实践,对公路桥涵台背回填施工工艺及质量控制进行了全面论述,提出了具体措施。     

对工程中预制楼板板缝开裂原因分析

本文从设计、材料、施工三方面,详细分析了工程中预制楼板板缝开裂的原因。