In one aspect the present invention provides indented structures that each include (a) a body defining a plurality of indentations, substantially all of the plurality of indentations including a surface layer including a biologically active substance; and (b) a body surface, wherein each of the plurality...http://www.google.de/patents/US6558422?utm_source=gb-gplus-sharePatent US6558422 - Structures having coated indentations
