 Rationale: Global analysis of biological markers is an established mechanism to study complex disease processes. The introduction of microarray technology and systems wide analysis has improved the understanding of various biological and disease processes. This revolution has been ongoing since the early 1990s. The rationale for performing these studies is to augment the understanding of the basic mechanisms of stroke in humans. As previously mentioned, there is no bona fide model of stroke and the researchers experimental design provides a rather simple in human model for cerebral ischemia. 