淋巴系统解剖精选文档.ppt

淋巴系统解剖淋巴系统解剖本讲稿第一页，共十五页Overview of the Lymphatic SystemIncludes,vessels,fluid,and nodes or nonsecreting glands.Lymphatic vessels convey fluid from the periphery to the veins.The fluid,lymph(=clear spring water),is what seeps out of the blood at the peripheral capillaries.Composition is similar to plasma without the proteinsLymphatic organs or tissues(glands)are filtering areas and arenas of lymphocyte maturation and competency.本讲稿第二页，共十五页Major Functions of Lymphatic SystemFiltration of lymphReturn of seeped fluid to c.v.system“Education”and production of immune system lymphocytesTransport of digested lipids from small intestinal lacteals 本讲稿第三页，共十五页Lymph CapillariesThin walled endothelium(no BM)with periodic one way valves.In general they parallel veins.Closed ends allow fluid flow inward only Pick up and recycle extra tissue fluid Lymph circulation due to?Compare to Fig.23.2本讲稿第四页，共十五页Location of Lymph CapillariesEverywhere,except for CNS and bone marrow,as well as cornea and cartilage.Special set of lymph capillaries in villi of small intestine=Lacteals本讲稿第五页，共十五页Damaged valves or blockedlymph vessels?Lymphatic vesselscomparable in structure to veins本讲稿第六页，共十五页Lymph capillaries converge to become collecting vessels and end up as eitherThoracic duct or right lymphatic ductThoracic(left lymphatic)ductLeft subclavian veinRight lymphatic ductRight subclavian veinCysterna ChyliFig 23.4本讲稿第七页，共十五页largest本讲稿第八页，共十五页LymphocytesAgranulocytes-large nuclei and small amount of cytoplasm Function in identification and inactivation/destruction of pathogensTypes of Lymphocytes1.T Cells-cellular immunity-specific for previously identified pathogensT Helper,T Killer,T Suppressor,and memory cells2.B Cells-humoral immunity-plasma cells produce antibodies specific to the antigen or pathogen;memory cells3.NK cells-non-specific,provide immunological surveillance本讲稿第九页，共十五页Bone Marrow:LymphopoiesisLymphocytes are later also produced in thymus,spleen and tonsilsFig 23.7本讲稿第十页，共十五页122lC.t.loaded with LymphocyteslLymphoid nodules are unencapsulated clusters of lymphocytes(1mm).Found beneath epithelial lining of respiratory,digestive&urinary tractslMucosa associated lymphatic tissue(MALT)in GI tract 5 tonsilsaggregate lymphoid nodules in small intestine(=Peyers patches)appendix-walls contain lymphoid tissueLymphoid Tissue=adenoids本讲稿第十一页，共十五页Lymph Nodes 500(1mm to 25 mm)Bean-shaped with hilusseveral afferent vessels,one efferent vessel Function?Popular term“lymph gland”is misnomer.Why?Contain lots of lymphocytes&MacrophagesClinical application:Swollen lymph nodesFig 23.9本讲稿第十二页，共十五页Distribution of LNsCervical lymph nodes-drain head and neckAxillary lymph nodes-drain arms and breastsPopliteal lymph nodes-drain legs,drain into Inguinal lymph nodes-drain lower limbThoracic lymph nodes-drain thoracic visceraAbdominal lymph nodes-drain pelvic regionIntestinal and mesenteric lymph nodes-drain abdominal viscera本讲稿第十三页，共十五页ThymusLocation above heart,posterior to sternumDivided into lobulesOnly lymphoid organ that does NOT fight antigens,it functions as“T-cell academy”Blood thymus barrier prevents premature stimulation of developing T-cellsInvolution after pubertyEpithelial cells produce thymic hormones本讲稿第十四页，共十五页Largest lymphoid organSoft and very blood richRed pulp sinusoids containing RBCswhite pulpwhite pulp lymphoid tissueMajor Functions:1.Initiation of Immune response to antigens in blood2.Removal of aged and defective RBCs3.Repository for new RBCs4.Fe salvaging,storage and recyclingSpleenFig 23-17Surfaces named for contacts:diaphragmatic,visceral,gastric,renal本讲稿第十五页，共十五页