tailieunhanh - Ebook High-Yield histopathology (second edition): Part 2

(BQ) Part 2 book "High-Yield histopathology" presents the following contents: Lymph node, spleen, esophagus and stomach, small intestine, large intestine, liver and gallbladder, exocrine pancreas and islets of langerhans, respiratory system, urinary system, hypophysis, thyroid, parathyroid,. Invite you to consult. | Chapter 13 Lymph Node General Features Figure 13-1 . A lymph node is a small encapsulated ovoid to bean-shaped gland that lies in the course of lymphatic vessels draining various anatomic regions. Histologically a lymph node is divided into the cortex and medulla. Migrating lymphocyte Figure 13-1 A Diagram of a lymph node. Note the afferent lymphatic vessels AL along the convex surface efferent lymphatic vessel EL artery A and vein V at the hilus outer cortex OC with lymphatic follicles LF many of which contain germinal centers inner cortex IC and medulla M . B Diagram showing the flow of lymph and blood through the lymph node. PCV postcapillary venule. C Light micrograph of a normal lymph node showing the subcap-sular sinus S outer cortex OC inner cortex IC and germinal center GC of a lymphatic follicle. D Electron micrograph of the boxed area in C showing a postcapillary venule within the inner cortex. Note the lymphocytes exiting the bloodstream to repopulate the lymph node. 135 136 CHAPTER 13 Outer Cortex consists of A. MATURE VIRGIN B CELLS. Mature B cells are organized into lymphatic follicles that may contain germinal centers. Germinal centers are evidence of activated B cells that begin the transformation into plasma cells. B. FOLLICULAR DENDRITIC CELLS. Follicular dendritic cells have an antigen-presenting function. C. MACROPHAGES D. FIBROBLASTS RETICULAR CELLS . Fibroblasts secrete type III collagen reticular fibers that form a stromal meshwork. 4 Inner Cortex also called the paracortex or thymic-dependent zone consists of A. MATURE T CELLS B. DENDRITIC CELLS. Dendritic cells have an antigen-presenting function. C. MACROPHAGES D. FIBROBLASTS RETICULAR CELLS . Fibroblasts secrete type III collagen reticular fibers that form a stromal meshwork. Medulla consists of A. LYMPHOCYTES B. PLASMA CELLS. Plasma cells increasingly populate the medulla of antigen-stimulated lymph nodes so that the medulla becomes a major site of immunoglobulin secretion. C. .