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.
Executive Summary. 1  The bloodâbrain barrier (BBB) is a significant obstacle to therapeutic delivery for CNS disorders. Among various strategies, nanobiotechnology plays an important role in facilitating drug delivery across the BBB. 2  Desirable characteristics of the ideal method of therapeutic delivery across the BBB are described in this article.