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Biomedical subjects

J F Stoltz

Publications and source records attributed to J F Stoltz.

At least 235 records · Page 13Linked to original sources
PubMed1975

[Measurement of blood viscosity using a rotatory viscosimeter with coaxial cylinders].

The authors describe a microviscosimeter with coaxial cylinders which requires only a small volume of sample. They draw up formulae permitting to obtain in a simplified way, fluid rheograms, in particular for biological fluids. Furthermore, they consider the use of this viscosimeter for the study of the rheological properties of blood and plasma. Thus, at 30 degrees C, the plasma and serum have a newtonian behaviour, whilst the viscosity of total blood depends mainly on the hematocrit and the rate of shearing. One may thus verify Casson's law (tau 1/2 = tauo 1/2 + S gamma 1/2) which represents approximately the rheological equation of normal blood and permits one to calculate a threshold for viscous outflow.

Blood Viscosity↗
PubMed1975

[An invariant of plasma viscosity].

Determination of "m" invariant cannot lead to an absolute measurement of plasmatic viscosity, because "m" increases with temperature. It allows however to compare data determined in various conditions.

Blood Viscosity↗
PubMed1975

[Physicochemical study of platelet aggregation by 3 polylysines].

The action of polylysines of various molecular weight on platelet behaviour is studied with the help of 3 techniques: photometric test, screen filtration pressure on PRP and electrophoretic mobility. Polylysines, which are polybasic substances, produce a platelet aggregation studied by photometry after a short period of latency. Aggregation, depending on the doses of poly-lysine and chiefly on the optic density, shows a "plateau" with the dose of 100 gamma/ml for poly-lysine L, of molecular weight 17000. The screen filtration pressure increases continuously in the presence of the polylysines studies. Finally, the platelet charge decreases. The results depend on the concentration of poly-lysine, and the optimal concentration which involves the more marked alterations is inversely proportional to the molecular weight of the polylysine studied.

Blood Platelets↗