a LANGE medical book CURRENT ESSENTIALS of MEDICINE Fourth Edition Edited by Lawrence M. Tierney, Jr., MD Professor of Medicine University of California, San Francisco Associate Chief of Medical Services Veterans Affairs Medical Center San Francisco, California Sanjay Saint, MD, MPH Associate Chief of Medicine, Ann Arbor VA Medical Center Director, VA/UM Patient Safety Enhancement Program Professor of Internal Medicine, University of Michigan Medical School Ann Arbor, Michigan Mary A. Whooley, MD Professor of Medicine, Epidemiology and Biostatistics University of California, San Francisco Department of Veterans Affairs Medical Center San Francisco, California New York Chicago San Francisco Lisbon London Madrid Mexico City Milan New Delhi San Juan Seoul Singapore Sydney Toronto Copyright © 2011, 2005, 2002, 1997 by The McGraw-Hill Companies, Inc. All rights reserved. Except as permitted under the United States Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or by any means, or stored in a database or retrieval system, without the prior written permission of the publisher. ISBN: 978-0-07-176665-4 MHID: 0-07-176665-0 The material in this eBook also appears in the print version of this title: ISBN: 978-0-07-163790-9, MHID: 0-07-163790-7. All trademarks are trademarks of their respective owners. Rather than put a trademark symbol after every occurrence of a trademarked name, we use names in an editorial fashion only, and to the benefit of the trademark owner, with no intention of infringement of the trademark. Where such designations appear in this book, they have been printed with initial caps. McGraw-Hill eBooks are available at special quantity discounts to use as premiums and sales promotions, or for use in corporate training programs. To contact a representative please e-mail us at
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