Abstract:Objective To explore the phenomenon of Deqi in the acupuncture process by modeling two different techniques of acupuncture therapy with viscoelastic theory. Methods Applying the established visoelastic theory and quasi-linear viscoelasticity theory of soft tissues, the calculated numerical results of two respective acupuncture techniques based on bi-dimensional polar coordinates by programming with Matlab 6.1 were analyzed. Results With the parameters of τ 1=0.0984,τ 2=8454.76 and C=0.0351, in low frequency domain(0～8Hz), energy consumption factor and Twirling-rotating technique were significantly affected by frequency. Furthermore, the whole plate energy consumption upon Lifting-Thrusting technique shows the extremism periodically with the cycle time of 8 Hz. Conclusion The energy consumption is significantly affected by those two different techniques in low frequency domain. In addition, the Lifting-Thrusting technique in low frequency domain would contribute to the explanation of the phenomenon of Deqi.

Abstract:Objective To measure arm's tremor of patients with neurological disease quantitatively. Methods Film images of light points which are irradiated to the center of cross, then the images are digitalized by computer. The maximum distance of light points departing the center of cross MR?the average distance of light points departing the center of cross AR and the total length of the track of light points TL are calculated. Results MR?AR?TL of patients with neurological disease are significantly different from those of normal people(P<0.05).Conclusion MR ?AR?TL can be referred as quantitative indexes of arm's tremor of patients with neurological disease.

Abstract:Objective To explore the influence of topical biomechanical environment in the fracture point after which was fixed with auto control micro motion locking nail (AMLN) on the fracture healing mode. Methods Twenty eight femoral shafts of fourteen sheep were fractured transversely and were fixed with AMLN or GK nails respectively. The animals were sacrificed at time point of one, two, four and eight weeks. The bony stiffness and intensity ,stress level in different fractural healing period and the rate of stress covered were measured. The mechanism of macro-and micro biomechanics in different fractural healing period were observed. Results ①The intensity of anti compression, anti flexion and anti-torsion in the fractural end after which fixed with AMLN is better than that fixed with GK nail. ② The stress level in the fractural end fixed with AMLN could recover completely at seven to eight weeks, which was four weeks earlier than GK nail fixation . ③ The rate of stress covered in the fractural end after which fixed with AMLN decline forty percent at initial stages, eighteen percent at metaphase and sixteen percent at advanced stage. Conclusion The design of AMLN accord with the guide line of plastic fixation. The geometry non anamorphosis which was constituted by the fixation set and the fractural far and near end was very firmly and settled. This fixation's disturbance to physical stress distribute in the fractural end was very lightly. AMLN fixation of fracture could resolve the balanced question between the stress conduct and the stress protection, it also could make the fracture end healing better, and make the fractural healing process speed up.

Abstract:Objective To obtain an experimental relationship between mechanical property and electrical property of an contracting muscle. Methods The tibial nerve of rabbits was stimulated by impulse current with different pulse width and different current intensity giving by electromyography, meanwhile the Conductive Amplitude of Motion Potential (CAMP) of the gastrocnemius and it's contractile force were recorded. Results Experimental curver of contractile force vs electromyographic signals were obtained.Conclusion The contractile force was positively correlative with the impulse current intensity, and had linear relationship with the Conductive Amplitude of Motion Potential (CAMP) as well as with the value of electromyographic integral.

Abstract:Objective To investigate the changes of the mechaniccal properties of hepatic portal vein in the pig with various ages and to provide mechanical data for pig-to-human liver xenotransplantation.Methods The hepatic portal vein of different ages of pig were used to conduct mechanical experiment, and the data of Pressure and Diameter was measuted to calculate the elastic modulus and compliance.Results The elastic modulus of hepatic portal vein of pig incresaed with aging and pressute in vessel, while the compliance descended with aging.Conclusion The mechanical properties of hepatic portal vein of pig change with aging, the pig matched the mechanical property of hepatic portal vein of human should be chosen for liver xenotransplantation.

Abstract:Objective The purpose of this study is to investigate the wave structure of cardiac tissue generated by action potential. Methods The used methods are numerical analysis of the cardiac model and Cmiss software of Graph tools. Results We obtain the spiral wave and its breakup on the surface of heart and the scroll wave in cardiac tissue. These theoretic results describe the changing of the action potential of cardiac tissue in detail.Conclusion The studying simulation results here identify with the experiment phenomena of excitable media.

Abstract:Objective To investigate the radial distribution of temperature for the oscillatory flow in artery, and its relationship with other mechanical quantities. Methods Considering oscillatory flow as the first-order terms, the equations of motion on the basis of Boussinesq's approximation can be treated by perturbation theory. Results The equations of oscillatory flow including temperature are derived, and the radial distributions of temperature, pressure and velocities for the oscillatory flow in artery are obtained. Conclusion (1)The distributions of temperature and velocities are closely related to oscillatory frequency, the amplitude of the temperature fluctuation is inverse proportional to oscillatory frequency.(2) With the increasing of the oscillatory frequency, the gradient of temperature and velocities is mainly restricted in the near-wall layers. (3) The distributions of temperature and axial velocity are comparable.

Abstract:Objective A testing apparatus for shear stress of endothelial cells was developed ,which provided a experimental platform for studying the response of the biological characteristics of cultured endothelial cells to hemodynamic environment. Methods Applying the theories of the hydrodynamics and hemodynamics, a testing apparatus for shear stress to endothelial cells was developed. Results Under both normal and abnormal physiological conditions, control and adjust this apparatus can accurately the values of the shear stress, vertical stress and pulsatile amplitude ,pulsatile frequency of the vertical stress. Conclusion This apparatus can simulate hemodynamic environment coincided with the physiological condition of the body.

Abstract:Objective Analyzed the biomechanical properties of cancellous bone in human femoral head. Methods The tension, compression, torsion, shear, bending and impact tests on the normal cancellous bones of femoral head were performed. Results The ultimate tensile and compressive strengths, modulus of elastic; ultimate torsional torque and shear strength; ultimate bending strength and impact work were obtained. Conclusion The ultimate strength and modulus of elastic are higher in compressive load than that in tensile load. The torsional strength is higher than shear strength. The bending strength is close to the compression strength.

Abstract:Objective To investigate the biomechanical behavior of patellar cartilage in human knee. Methods Eight human fresh patellar cartilage were used. One-dimensional tensile test and stress relaxation test were performed. Results The destructive load?stretchy ratio?Lagrange spreading stress?Lagrange spreading strain, creep were obtained. The data of stress and strain was fitting with polynomial by the least square method. In addition, the equations of stress relaxation and creep were also obtained. Based on Feng YZ's the semi-linear theory G(t) formula, the constitutive equation K(λ,t)=G(t)T (e) (λ) was obtained. Conclusion The destructive load in one-directional tensile test is 38.54±4.18N, the stretchy ratio is 1.312±0.018, the spreading stress is 6.65±0.83MPa and the strain is 34.0±3.6%; Stress relaxation occurs during the first 7200 second and both of stress relaxation curve and creep curve are the logarithmic relation relative to time.

Abstract:血流动力学、血液灌注、药物动力学、血管内介入疗法等临床诊断和研究领域对无创性血流测量的需求日益增多。作者在分析了无创性血流测量的临床和基础意义后 ,总结了无创性血流测量的各种方法。重点介绍了超声多普勒和核磁共振测速技术的原理、方法、应用及其优缺点。在流场定量测量和血流动力学基础研究方面 ,核磁共振测速技术显示出潜在的优势

Abstract:膝关节是人体最重要的关节之一。对膝关节的生物力学性质和行为的正确认识有助于临床上各类膝关节伤病的治疗。模型是研究生物力学系统的有效手段 ,本文回顾了近年来国内外学者提出的若干膝关节力学模型 ,分析了其优点及局限性。提出了膝关节模型的发展趋势 ,为进一步探讨膝关节模型提供了参考和借鉴