The Bulletin of Medical and Clinical Research (BMCR) is one of the new advanced Book series which focused on the new issues and developments in all aspects of general & scientific medical research and clinical practice. This volume is a welcome contribution to the all areas of Medical and Clinical Research. It is concise and accessible, yet covers the field comprehensively. Also, it demonstrates the deep understanding of the diverse theories, and presents the various viewpoints and approaches in an easily readable fashion. This book is of assistance to the medical students as well as the experienced practitioner.