Decoodt P, Du Bois R, Gassee J P, Verniory A, Lambert P P
Comput Programs Biomed. 1975 Mar;4(3):180-8. doi: 10.1016/0010-468x(75)90019-7.
The transport of water and of macromolecules across the glomerular membrane of the kidney depends on the membrane parameters (radius, length and number of pores) as well as on the hydrostatic and oncotic pressures on either side of the membrane. The filtration pressure decreases along the capillary loops from afferent to efferent end. Water and solute flows are thus given by a system of two differential equations. The sieving coefficient of the macromolecules is the ratio of solute to water flow. In the program described the differential equations are solved by the Runge-Kutta method (fourth order). Rosenbrock's method of minimization is used to adjust the theoretical to the experimental sieving coefficients. The pore radius, total pore area per unit of path length and conductance of the membrane, as well as the intracapillary hydrostatic pressure and its gradient can thus be determined.
水和大分子物质通过肾肾小球膜的转运取决于膜参数（半径、长度和孔隙数量），以及膜两侧的流体静压和胶体渗透压。滤过压沿着毛细血管袢从入球端到出球端逐渐降低。因此，水和溶质的流动由一个包含两个微分方程的系统给出。大分子物质的筛滤系数是溶质流量与水流量的比值。在所描述的程序中，微分方程采用龙格 - 库塔方法（四阶）求解。使用罗森布罗克最小化方法将理论筛滤系数调整为实验筛滤系数。由此可以确定孔隙半径、单位路径长度的总孔隙面积、膜的传导率，以及毛细血管内流体静压及其梯度。
