tailieunhanh - Ebook For the first aid USMLE step 1 2017: Part 2

Part 2 book “For the first aid USMLE step 1 2017” has contents: Neurology and special senses, musculoskeletal, skin, and connective tissue, anatomy, embryology, and neuroscience, behavioral science, cell biology and histology, microbiology and immunology, pharmacology, pharmacology, how to use the database, and other contents. | HIGH-YIELD SYSTEMS Hematology and Oncology “Of all that is written, I love only what a person has written with his own blood.” —Friedrich Nietzsche “I used to get stressed out, but my cancer has put everything into perspective.” —Delta Goodrem ` Anatomy 386 ` Physiology 389 ` Pathology 394 ` Pharmacology 413 “The best blood will at some time get into a fool or a mosquito.” —Austin O’Malley “Carcinoma works cunningly from the inside out. Detection and treatment often work more slowly and gropingly, from the outside in.” —Christopher Hitchens Study tip: When reviewing oncologic drugs, focus on mechanisms and side effects rather than details of clinical uses, which may be lower yield. 385 386 SEC TION III HEMATOLOGY AND ONCOLOGY ` HEMATOLOGY AND ONCOLOGY—ANATOMY ` HEMATOLOGY AND ONCOLOGY—ANATOMY Erythrocyte A Thrombocyte (platelet) A Leukocyte Neutrophil A Carries O2 to tissues and CO2 to lungs. Anucleate and lacks organelles; biconcave A , with large surface area-to-volume ratio for rapid gas exchange. Life span of 120 days. Source of energy is glucose (90% used in glycolysis, 10% used in HMP shunt). Membrane contains Cl−/HCO3− antiporter, which allows RBCs to export HCO3− and transport CO2 from the periphery to the lungs for elimination. Eryth = red; cyte = cell. Erythrocytosis = polycythemia = q hematocrit. Anisocytosis = varying sizes. Poikilocytosis = varying shapes. Reticulocyte = immature RBC; reflects erythroid proliferation. Bluish color on Wright-Giemsa stain of reticulocytes represents residual ribosomal RNA. Involved in 1° hemostasis. Small cytoplasmic fragment A derived from megakaryocytes. Life span of 8–10 days. When activated by endothelial injury, aggregates with other platelets and interacts with fibrinogen to form platelet plug. Contains dense granules (ADP, Ca2+) and α granules (vWF, fibrinogen, fibronectin). Approximately 1⁄3 of platelet pool is stored in the spleen. Thrombocytopenia or r platelet function results in