[Mitotic anomalies observed in fibroblasts of chicken embryo cultured in vitro with 80% oxygen].

Fibroblasts cultivated in vitro were observed during mitosis. Already after 24 h of culture in 80% oxygen, some anomalies affect mitosis (atypical mitosis): abnormalities of the usual mitosis stages, chromosomal aberrations. Mitosis is interrupted at metaphase during the first and second day of culture in hyperoxia and at prophase (prometaphase) during the third day. The new mode of nuclear division is discussed.