抄録
Ninety six oocytes from 44 females were cultured in various hours in the chemically defined medium. Ultrastructures of the cultured oocytes were observed by both transmission and scanning electron microscopes. After 40 hours of culture, some of them resumed meiosis and reached to the second meiotic metaphase. The figure of clearly arborizating microvilli were observed. Tubular aggregates existed more in the matured oocyte than the follicular oocyte. The annulate lamellae could not be found in the present study. Other structures such as the granulosa cells, zona pellucida, cytoplasmic organelles and nucleus showed almost the same figures as observed in other studies.
