барьер, преграда, препятствие
- biogeographical barrier to dispersal
- blood-air barrier
- blood-aqueous barrier
- blood-brain barrier
- blood-cerebrospinal fluid barrier
- blood-gas barrier
- blood-ocular barrier
- hematoencephalic barrier
- natural barrier
- permeability barrier
- placental barrier
- transplacental barrier
- transplantation barrier