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In this paper, numerical results on steady laminar flow of blood through an artery having two successive identical axisymmetric restrictions are presented, at varying degrees of restrictions. Physically, such a flow has features in common with steady blood flow through an artery with multiple stenoses. Additionally, results are presented for the blood flow through an artery in the presence of a single restriction, for comparison. The artery has been modelled as a tube with a rigid wall. The rheological characteristics of blood have been assumed both as Newtonian and non-Newtonian. Three different non-Newtonian models of blood – power law, Quemada, and Carreau–Yasuda models – have been considered in the analysis. The haemodynamic effects of the restrictions on the axial velocity distribution, recirculation zones formed downstream to the restrictions, the wall shear stress, and the pressure drop in the artery have been analysed. The irreversible pressure loss coefficient is calculated from the pressure drop and its variation with the degree of stenosis is obtained. [ABSTRACT FROM AUTHOR]

Platelet 3H ketanserin binding was studied in 33 patients of migraine and 30 healthy controls. The binding characteristics: equilibrium dissociation constant (Kd) and maximal number of binding sites (Bmax) determined by Scatchard analysis revealed a significant decrease in Kd and no change in Bmax in migraine cases. No correlation was observed between the Kd and Bmax with the clinical features of migraine. The findings of the present study show that there is a decreased affinity of platelet 5-HT2 receptors in migraine. [ABSTRACT FROM AUTHOR]