Type O negative blood (red cells) can be transfused to patients of all blood types. It is always in great demand and often in short supply. Type AB positive plasma can be transfused to patients of all other blood types. AB plasma is also usually in short supply.
Blood-brain barrier. A blockade of cells separating the circulating blood from elements of the central nervous system (CNS); it acts as a filter, preventing many substances from entering the central nervous system.
About. The blood brain barrier (BBB) is a dynamic interface that separates the brain from the circulatory system and protects the central nervous system (CNS) from potentially harmful chemicals while regulating transport of essential molecules and maintaining a stable environment.