Responsiveness to progesterone and potassium channel blockers 4-aminopyridine, tetraethylammonium and free Ca2+ contentration in spermatozoa of patients with oligozoospermia/leucocytospermia - R. V. Fafula; G. V. Danylovych; A. S. Besedina; O. V. Melnyk; Z. D. Vorobets (The Ukrainian Biochemical Journal, 2018)