[Proliferation of bone marrow cells upon exposure to constant magnetic fields of ultra-high strength].

A study was made of the 0.5--24 hour effects of the stable magnetic field (SMF), with 9.9--42.4 kOe strength and 0.2--3.5 kOe/cm strength gradient, on the mitotic activity and bone marrow cell number in mice. Short-term treatments were shown to stimulate, and prolonged ones to inhibit mitotic activity, the degree of inhibition correlating with the strength and strenght gradient of SMF. The rate of mitotic index recovery was the smaller the longer the treatment and the higher the strength of SMF. With the most pronounced inhibition of the mitotic activity, the number of bone marrow cells was seen reduced. No increased frequency of aberrant mitoses in bone marrow cells has been noticed following the effect of SMF.