Biorheology - Volume 17, issue 1-2

Authors: Copley, Alfred L.

Article Type: Editorial

DOI: 10.3233/BIR-1980-171-201

Citation: Biorheology, vol. 17, no. 1-2, pp. 1-2, 1980

Authors: Copley, Alfred L.

Article Type: Editorial

DOI: 10.3233/BIR-1980-171-202

Citation: Biorheology, vol. 17, no. 1-2, pp. 3-4, 1980

Authors: Copley, Alfred L.

Article Type: Editorial

DOI: 10.3233/BIR-1980-171-203

Citation: Biorheology, vol. 17, no. 1-2, pp. 5-7, 1980

Authors: Dawidson, Ingemar J.A. | Gelin, Lars-Erik | Haglind, Eva

Article Type: Research Article

Abstract: The viscosity of whole blood (WB), plasma (P), and packed cells (PC) was measured in a Wells-Brookfield cone plate viscometer on blood from dogs undergoing surgical shock and hemodilution with different plasma substitutes and on human ACD-blood diluted in vitro to comparable concentrations of colloids. Erythrocyte sedimentation rate (ESR) and microscopic red cell aggregate count were used as in vitro indices of red cell aggregation. During three hours of intestinal shock WB viscosity increased by 20 %, hematocrit increased from 50.9 to 59. 1 %, P viscosity was unchanged and PC viscosity increased by 6 %. When compared at equal …hematocrit drop, Ringer’s acetate decreased WB viscosity more than albumin, ACD-plasma, dextran 70 and gelatin in this order both on blood diluted in vitro and in vivo. Since the duration of volume expansion in vivo after Ringer’s solution was very transient the absolute decrease of viscosity was less than that observed after all other solutions except gelatin. P viscosity increased with dextran 70, was unchanged with ACD-plasma, dextran 40, and gelatin and decreased with albumin and Ringer’s acetate dilution. A marked red cell aggregation occurred with dextran 70 and gelatin with increasing concentration. No aggregation of red cells was seen with dextran 40, albumin, or Ringer’s acetate. It is concluded that lasting hemodilution in vivo is best achieved with albumin and dextran 40 based on their viscosity influences, volume expansion duration and their lack of red cell aggregation properties. Show more

DOI: 10.3233/BIR-1980-171-204

Citation: Biorheology, vol. 17, no. 1-2, pp. 9-16, 1980

Authors: Heuser, G. | Opitz, R.

Article Type: Research Article

Abstract: A Couette viscometer with axial flow is proposed which allows blood to be exposed to defined shear stresses of short duration. A prototype of this viscometer is tested. By measurements and simple calculations the range of application is established. Measurements with blood show the possibility to control the flow conditions which may lead to haemolysis.

DOI: 10.3233/BIR-1980-171-205

Citation: Biorheology, vol. 17, no. 1-2, pp. 17-24, 1980

Authors: Downs, A. | Litt, M. | Kron, R.E.

Article Type: Research Article

Abstract: A capillary viscosmeter is described which allows measurement of the shear rate dependency of fresh blood viscosity at low shear rates. The instrument has been used in a preliminary study to evaluate differences between fresh and EDTA anticoagulated blood. In a shear rate range of 0.5 to 1.3 sec−1 the viscosity of fresh blood is more strongly dependent on hematocrit than is the viscosity of EDTA anticoagulated blood. Also, the viscosity of anticoagulated blood is more sensitive to day-to-day variations than is that of fresh blood. For some subjects, such variations may amount to as much as 30%.

DOI: 10.3233/BIR-1980-171-206

Citation: Biorheology, vol. 17, no. 1-2, pp. 25-35, 1980

Authors: Woo, Savio L-Y.

Article Type: Introduction

DOI: 10.3233/BIR-1980-171-207

Citation: Biorheology, vol. 17, no. 1-2, pp. 37-37, 1980

Authors: Woo, Savio L-Y.

Article Type: Research Article

DOI: 10.3233/BIR-1980-171-208

Citation: Biorheology, vol. 17, no. 1-2, pp. 39-43, 1980

Authors: Hoffman, Allan S.

Article Type: Research Article

Abstract: Enzymes are widely used to remove selectively various stress bearing components of connective tissues before, during or after application of stress. This paper surveys and critically reviews these techniques.

DOI: 10.3233/BIR-1980-171-209

Citation: Biorheology, vol. 17, no. 1-2, pp. 45-50, 1980

Authors: Nimni, Marcel E.

Article Type: Research Article

Abstract: Crosslinking of collagen is a prerequisite for the collagen fibers to withstand the physical stresses to which they are exposed. Significant progress has been made in understanding the functional groups on the molecule which are involved in the formation of crosslinks. Chemical agents, in particular bifunctional aldehydes such as glutaraldehyde, have found applications in the area of bioprostheses. They increase the resistance of collagen to biological degradation while increasing its mechanical resistance and decreasing its immunogenicity. It is to be expected that our increasing understanding of the molecular structure of collagen will allow us to further modulate its process of …biosynthesis and turnover as well as to benefit from the use of chemically modified collagen fibers in the development of novel bioprostheses. Show more

DOI: 10.3233/BIR-1980-171-210

Citation: Biorheology, vol. 17, no. 1-2, pp. 51-82, 1980