Mathematical modeling of oxygen consumption in the human body

Oxygen uptake as increment above the resting value was measured after the onset of constant-load exercise, the value of uptake increases approximately exponentially to its steady-state value Vs according to the equation. V[t] = V[s] [1-e[-kt]]K rate constant can be calculated either graphically or analytically. The results of others on eight subjects we used to determine K by both methods. Good agreement were found between the two techniques

Counter-current flow in artificial kidneys

The he parameters controlling the design and function of artificial 1 kidney systems, namely surface area of the transfer medium, [membrane], its permeability as well as operating conditions such as the rate of flow of both the blood and dialysate were correlated, The obtained correlation provides a means For calculating the artificial kidney performance [dialysance] in terms of blood flow rat blood to dialysate flow rate ratio, membrane surface area and membrane permeability : D= Q B[1- [1-k] / [e[1-k] PA / Q[B-k]] < 1 Considering the equation commonly used for calculating membrane permeability i.e. Renkin formula it is worth noting that it can only be applied for specific cases where blood to dialysate flow rates are extremely low and it may be considered as a specific case of the predicted equation

formula blood viscosity with critical appraisal of the available ones

The aim of this work is to criticize the available formulas and utilizing such as formulas with a correction factor to develop new formulas with a correction factor to develop a new formula for blood viscosity. Also, some of viscosity syndromes are presented

Unsteady state behaviour of the nephron in case of renal vein occlusion

Disturbances in circulatory dynamics in some parts of the vascular bed may initiate disturbances [disorders] to some vital organ functions. Disturbances in Renal circulatory dynamics may lead, if not reated, to renal disorder of different degrees of complexity according to the prevailing dynamic pattern. The paper presents the effect of renal vein occlusion on the perpetuation of renal diseases as manifested by the biochemical changes. The two coaxial cylinders model proves to be effective in elucidating the qualitative pathogenic features of renal disease as indicated by the elevation of the blood urea level. The exact quantitative picture depends upon the availability of micro puncture data. It is suggested that the results is equally valid for renal artery stenosis

Effects of the major parameters affecting the clot formation

The effects of the major parameters affecting the clot formation such as time, temperature, and flowrate are investigated using a constant-low machine of a closed loop-circuit type. Furthermore, the effects of adding different concentrations of [heparin] as anticoagulant; capramol and [trasylol] are also investigation both stationary tanks and agitated tanks in addition to the closed loop-circuit of constant flow. The following relations were deduced from the results of this study: I] W[c] = 35.995 W[0.01 z]/ j[0.052] T [1.23] L[0.Iz6] where w[e] is the weight ratio of the clot. J is the time, t is the temperature, w is the angular velocity. L is the flowrate. Although the injection of heparin at low concentrations [below 5000 units / body] has no effect, yet at high concentrations [in the range of 15000, 20000 and 25000 units/adult body] heparin acts as fibrinolytic drug. Also it is shown that both [capramol] and trasylol reveal fibrinolytic activity, which is attributed to their known inhibitory action to plasmin

new concept in the design of an intensive care unit for haemodialysis

The intensive care units are extensively used in Egypt for haemodialysis. The paper discussed the development of the basis utilized for the design of renal intensive care units. The design should fulfill, maximum utilization of resources, area and time. The paper suggested an integrated concept for the planning of such units. The suggested design presented in the paper suits developing countries

Steady state behaviour of the ascending limb of Henle's loop in a nephron below the juxta-medullary apparatus

The nature of many kidney diseases is still unknown and so the therapy. The reasons for such uncertainty are numerous but, the most important is the great difficulty to study events successfully in the cellular level and the inaccurate results for experiments obtained at such level. So many of the phenomena which cause disease are still unknown and subsequently they are the subject of many contradicting theories. The strong tools of modeling is now adapted to predict concentration profile along the ascending limb of Henle. The reason for such a choice lies in its difference from that of the descending limbs as being performing active transport and satisfying requirements of modeling. It is greatly similar to plug flow reactor in nature

economic evaluation of hemodialysis in Egypt

The annual mortality due to renal failure in Egypt is estimated to be three thousands. About half of this figure may be saved by regular dialytic treatment and the remainder represents cases of acute renal failure. Also, the artificial kidney is used successfully in the treatment of poisoning. The previous facts impose the need for developing artificial kidney service in Egypt. Planning for haemodialysis in Egypt necessitates the analysis of the cost of Haemodialysis Center for different types of machines with the aim of reducing the cost of such expensive service. The following study is based on the available cost data of the foreign companies, since no data are available about the local materials for the following reasons: No units have been built in Egypt yet; the materials produced locally are for other purposes and need some modification before being used for haemodialysis