From Big Medical Encyclopedia

FAVORSKII METHOD (B. A. Favorskii; a synonym a method Ramón-and-Kakha-la — Favorskii) — a way of impregnation by silver of pieces of fabric for identification of nervous cells, fibers and the terminations. It is offered by B. A. Favorskii in 1930.

Thin (to 0,5 cm) plates of fabric fix during 24 hours in 80% alcohol, on each 50 ml to-rogo add 30 drops ant (at identification of nervous cells) or ice acetic (at identification of nerve fibrils and their terminations) to - you. The enveloping layer of pieces is cut off then them for the purpose of fixing place in 85% alcohol again for 24 hours, and then postpone to 48 hours in 96% alcohol, on 50 ml to-rogo add 1 ml of 25% of spirit of ammonia. After that pieces wash out in the replaced distilled water (3 — 6 hours) and on 24 — 48 hours place in anhydrous pyridine. After washing in flowing (24 hours) and in replaced distilled (3 — 6 hours) to water pieces during

1 — 2 week impregnate in the solution of az of tnokisly silver replaced 2 — 3% (in the thermostat at f 37 ° in the dark). Silver is recovered in developer (2 — 4 g pyrogallic to - you or hydrochinone, 100 ml of a distilled water and 10 ml of neutral formalin), and in the beginning pieces rinse in a small amount of developer, and then place on 1 — 3 days in fresh solution. From developer pieces transfer to 70% alcohol (not longer than for 90 min.), dehydrate and fill in in photoxylin or paraffin; microtome cuts are concluded in balm. Intracellular neurofibrilla, axial cylinders of nerve fibrils, nerve terminations gain dark brown color and are well emitted on a light yellow background. Advantage of a method before a classical way (see Ramone-and-Kakhalya methods) consists in uniform impregnation and rather small compression of fabric.

See also Histologic methods of a research, Impregnation, Silverings methods.

Bibliography: Merkulov G. A. Course

of the patologogistologichesky equipment, page 209, L., 1969; F and in about r with to and y B. A. Elected heads of histology and histopathology of a nervous system, D., 1946.

Ya. E. Hesinonim