At present,total hip arthroplasty (THA) is the primary treatment for hip diseases such as femoral head necrosis and developmental dysplasia of the hip.It has good effects in reducing pain and improving joint function.The appearance of modular hip prosthesis facilitates adjustment of limb length and femoral offset.However,the wear between the interface of hip prosthesis can lead to inflammatory pseudotumor,osteolysis and other adverse reactions.To explore the risk factors of wear between hip prosthesis interface is helpful to improve the design and manufacturing concept of the product,improve the product performance,help surgeons optimize the operation technology and reduce the impact of human factors on the wear of the prosthesis.Many literatures have reported the mechanism of wear between the head-acetabula interface of prosthesis.The mechanism of wear between the interfaces has been described relatively clearly.In addition to the head-acetabula interface,the wear between the head-neck interface is another major cause of unexplained pain around the joint and prosthesis loosening after hip replacement.Many factors affect head-neck wear.The design of prosthesis (such as prosthesis material and prosthesis taper),surgical technology (such as impact strength and prosthesis mismatch) and patient factors (such as age,gender and activity) have important impact on head-neck wear.Adverse reactions caused by head-neck wear have also been widely concerned.However,there is no considerable solution for wear prevention.Thus,we should optimize the design of prosthesis,improve the surgical technology,and guide the rehabilitation of patients to prevent wear.In order to improve the attention of joint surgeons,the present paper reviews the literatures and analyzes the risk factors of head-neck interface wear and the clinical manifestations caused by head-neck wear.
At present the viscosity survey is developed to high accuracy,automation,real-time on-line direction.This design aimed at the control system of the rotation mode of vibrations,high temperature melt system viscometer,carried out the design on its software and hardware.The hardware included the module of profile synthesis,time survey,data acquisition.The software was realized in the environment designated visible Windows operating system,used LabVIEW as the development tool,developed one kind of practical reliable control system
锅炉微计算机控制,是近年来开发的一项新技术,它是微型计算机软、硬件、自动控制、锅炉节能等几项技术紧密结合的产物,我国现有中、小型锅炉30多万台,每年耗煤量占我国原煤产量的1/3,目前大多数工业锅炉仍处于能耗高、浪费大、环境污染等严重的生产状态。提高热效率,降低耗煤量,用微机进行控制是一件具有深远意义的工作。