[Role of factors affecting the diameter of capillaries in postmortem examinations]

In 20 mongrel dogs by means of four methods (injection of Indian ink and gelatin, impregnation after Bielschowsky--Gros, injection of 1% colloid silver solution and erythrocytes staining with benzidine) capillaries in the musculus sternomastoideus have been revealed. The capillary diameters are measured with a screw ocular micrometer and treated by means of variational statistics methods, three-factor dispersion analysis including. The role of the factors affecting the capillary diameters in the process of their revealing is defined. The controlled factors determine 81% of total variation, out of them the investigation methods--70%, individual variability of the animals--1.2%, conditions for making preparations--0.1% and 2.9% are connected with the interrelations of the factors mentioned. Each method makes certain distortions in the measurements, but, at the same time, is specific for revealing various structural details. Therefore, in order to study the capillaries, it is necessary to apply their combinations.