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The study of blood and hematologic disorders has special importance for medical students as well as physicians at all stages of their training. Few specialties have such a broad impact on other medical disciplines. A competent hematologist must be well grounded in pathology, internal medicine, pediatrics, and surgery. Conversely, both generalists and other specialists regularly encounter patients with anemia, hemorrhage, thrombosis, and hematologic malignancies. For many students, the close kinship of hematology with laboratory medicine is an added virtue. Few medical disciplines enjoy such a rich array of reliable and informative diagnostic tests, and none has stronger underpinnings in contemporary molecular and cell biology and molecular pathology.
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The focus of the second edition of our book continues to be the physiologic principles underlying the regulation and function of blood cells and hemostasis as well as the pathophysiologic mechanisms responsible for the development of blood disorders. Throughout the book, we place more emphasis on principles than practice, avoiding technical details pertaining to diagnostic tests and procedures as well as the compilation of specific drugs and dosages. Instead, we frame our discussion of disease diagnosis and management around underlying pathogenesis, in the belief that a firm grounding in physiologic and pathophysiologic mechanisms is the bedrock of medical education.
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The organization and contents of the book are based on a 3-week hematology course given to students at Harvard Medical School. All of the authors are lecturers in this course, and many of the figures have been taken directly or adapted from their lectures. These authors also are the sources of updates and revisions found in the second edition, which include new summary boxes, revised and improved figures, and new formatting that improves the "readability" of our text. All figures were redrawn by a single artist and vetted by both of the editors, as was all of the text. We hope that these measures have reinforced what we view as the strengths of our book: uniformity of style, clarity, brevity, and a high level of scientific rigor and clinical relevance.
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Although our book originated as a companion to a second-year medical school hematology course, we are well aware of curriculum changes under way that may postpone or eliminate such courses. Indeed, the Harvard Medical School second-year hematology course is being phased out as of 2017, to be "replaced" by an upper year course that can be selected by students with a particular interest in hematology and hematologic disorders. We note that while the teaching of hematology and the clinical management of hematologic disorders change with time, the underlying pathogenic principles are constants. Thus, while we anticipate that future readers may seek out our book at later stages of their medical education, we also believe that the relevance and value of the text for students will remain strong. In fact, as the teaching of hematology and its underlying principles becomes more diffuse, our text may take on even greater value as a focused primer to be referred to when students first encounter patients with hematologic disorders.
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We are indebted to a number of individuals who helped bring our book to fruition. Karen Edmonson, Harriet Lebowitz and Vastavikta Sharma at McGraw-Hill provided critical editorial advice including guidance on how to make the book useful and interesting to students. Muriel Goutas provided invaluable secretarial help. Dr. Jeff Kutok (Brigham and Women's Hospital) and Carola von Kapff contributed images of some of the peripheral smears used in the book. We thank students at Harvard Medical School who have provided valuable feedback about strengths and weaknesses of the first edition. Finally, we thank our wives, Erin Malone and Betsy Bunn, for their love and support.
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Jon C. Aster
H. Franklin Bunn
January 2016