http://www.nlm.nih.gov/medlineplus/spanish/ency/esp_imagepages/9129.htm
Actualizado: 2/16/2011
Versión en inglés revisada por: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc