lymph node


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lymph

 [limf]
a transparent, usually slightly yellow, often opalescent liquid found within the lymphatic vessels, and collected from tissues in all parts of the body and returned to the blood via the lymphatic system. It is about 95 per cent water; the remainder consists of plasma proteins and other chemical substances contained in the blood plasma, but in slightly smaller percentage than in plasma. Its cellular component consists chiefly of lymphocytes.

The body contains three main kinds of fluid: blood, tissue fluid, and lymph. The blood consists of the blood cells and platelets, the plasma, or fluid portion, and a variety of chemical substances dissolved in the plasma. When the plasma, without its solid particles and some of its dissolved substances, seeps through the capillary walls and circulates among the body tissues, it is known as tissue fluid. When this fluid is drained from the tissues and collected by the lymphatic system, it is called lymph. The lymphatic system eventually returns the lymph to the blood, where it again becomes plasma. This movement of fluid through the body is described under circulatory system.
lymph node any of the accumulations of lymphoid tissue organized as definite lymphoid organs along the course of lymphatic vessels (see accompanying illustration); they consist of an outer cortical and an inner medullary part. Lymph nodes are the main source of lymphocytes of the peripheral blood and, as part of the reticuloendothelial system, serve as a defense mechanism by removing noxious agents such as bacteria and toxins, and probably play a role in antibody formation. Sometimes called, incorrectly, lymph gland. Called also lymph or lymphatic follicle and lymphatic nodule.
Location of clusters of superficial lymph nodes. From Applegate, 2000.

node

 [nōd]
a small mass of tissue in the form of a swelling, knot, or protuberance, either normal or pathological. adj., adj no´dal.
node of Aschoff and Tawara atrioventricular node.
atrioventricular node (AV node) a collection of cardiac fibers at the base of the interatrial septum that transmits the cardiac impulse initiated by the sinoatrial node.
Bouchard's n's cartilaginous and bony enlargements of the proximal interphalangeal joints of the fingers in degenerative joint disease; such nodes on the distal joints are called Heberden's nodes.
Delphian node a lymph node encased in the fascia in the midline just above the thyroid isthmus, so called because it is exposed first at operation and, if diseased, is indicative of disease of the thyroid gland.
Flack's node sinoatrial node.
Heberden's n's nodular protrusions on the phalanges at the distal interphalangeal joints of the fingers in osteoarthritis. Similar nodes on the proximal joints are called bouchard's nodes.
Comparison of Heberden's nodes (seen in patients with osteoarthritis) with Bouchard's nodes (seen in patients with rheumatoid arthritis). From Copstead and Banasik, 2000.
hemal n's nodes with a rich content of erythrocytes within sinuses, found near large blood vessels along the ventral side of the vertebrae and near the spleen and kidneys in various mammals, especially ruminants, having functions probably like those of the spleen; their presence in humans is doubtful.
Keith's node (Keith-Flack node) sinoatrial node.
Legendre's n's Bouchard's nodes.
lymph node see lymph node.
Osler's n's small, raised, swollen, tender areas, bluish or sometimes pink or red, due to inflammation around the site of lodgement of small infected emboli in distal arterioles; they occur commonly in the pads of the fingers or toes, in the palms, or in the soles and are practically pathognomonic for subacute bacterial endocarditis.
Parrot's n's bony nodes on the outer table of the skull of infants with congenital syphilis.
n's of Ranvier constrictions of myelinated nerve fibers at regular intervals at which the myelin sheath is absent and the axon is enclosed only by Schwann cell processes.
Schmorl's node an irregular or hemispherical bone defect in the upper or lower margin of the body of a vertebra into which the nucleus pulposus of the intervertebral disk herniates.
sentinel node
1. the first lymph node to receive drainage from a tumor; used to determine whether there is lymphatic metastasis in certain types of cancer. If this node is negative for malignancy, others “upstream” from it are usually also negative.
signal node an enlarged supraclavicular lymph node; often the first sign of a malignant abdominal tumor.
singer's n's vocal cord nodules.
sinoatrial node a collection of atypical muscle fibers in the wall of the right atrium where the rhythm of cardiac contraction is usually established; therefore also referred to as the pacemaker of the heart. Called also SA node.
syphilitic node a swelling on a bone due to syphilitic periostitis.
node of Tawara atrioventricular node.
teacher's n's vocal cord nodules.
Troisier's node (Virchow's node) sentinel node.

lymph node

(limf nōd), [TA]
One of numerous round, oval, or bean-shaped bodies located along the course of lymphatic vessels, varying greatly in size (1-25 mm in diameter) and usually presenting a depressed area, the hilum, on one side through which blood vessels enter and efferent lymphatic vessels emerge. The structure consists of a fibrous capsule and internal trabeculae supporting lymphoid tissue and lymph sinuses; lymphoid tissue is arranged in nodules in the cortex and cords in the medulla of a node, with afferent vessels entering at many points of the periphery.

lymph node

n.
Any of the small bodies located along the vessels of the lymphatic system (in humans notably in the neck, armpits, and groin) that filter bacteria and foreign particles from lymph fluid. During infection, lymph nodes may become swollen with activated lymphocytes. Also called lymph gland.

lymph node

Etymology: L, lympha + nodus, knot
one of the many small oval structures that filter the lymph and fight infection and in which lymphocytes, monocytes, and plasma cells are formed. The lymph nodes are of different sizes, some as small as pinheads, others as large as lima beans. Each node is enclosed in a capsule, is composed of a lighter-colored cortical part and a darker medullary part, and consists of closely packed lymphocytes, reticular connective tissue laced by trabeculae, and three kinds of sinuses: subcapsular, cortical, and medullary. Lymph flows into the node through afferent lymphatic vessels that open into the subcapsular sinuses. Most lymph nodes are clustered in areas such as the mouth, the neck, the lower arm, the axilla, and the groin. The lymphatic network and nodes of the breast are especially crucial in the diagnosis and treatment of breast cancer. Also called lymph gland.
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Lymph node
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Lymph node

lymph node

(limf nōd) [TA]
One of numerous round, oval, or bean-shaped bodies located along the course of lymphatic vessels, varying greatly in size (1-25 mm in diameter) and usually presenting a depressed area, the hilum, on one side through which afferent lymphatic vessels enter and efferent lymphatic vessels emerge. The structure consists of a fibrous capsule and internal trabeculae supporting lymphoid tissue and lymph sinuses; lymphoid tissue is arranged in nodules in the cortex and cords in the medulla of a node, with afferent vessels entering at many points of the periphery.
Synonym(s): nodus lymphaticus [TA] , nodus lymphoideus [TA] , lymph gland, lymphoglandula, lymphonodus.
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LYMPH NODE

lymph node

A small encapsulated lymphoid organ that filters lymph. Lymph nodes are found at junctions or branches along the lymphatics. They provide sites where immune responses can be generated through the interaction of antigens, macrophages, dendritic cells and lymphocytes. See: illustration; immune response; inflammation; lymph; lymphocyteLymph nodes are 0.1-2.5 cm long kidney-shaped aggregates of lymphocytes and macrophages embedded in a meshwork reticulum composed of thin collagen fibers. At each lymph node, an artery enters through a surface indentation (the hilum) alongside an exiting vein and an exiting (efferent) lymphatic vessel; a number of afferent lymphatic vessels enter the lymph node at other sites. Inside lymph nodes, lymph slowly flows through endothelial sinuses lined by lymphocytes and macrophages. Macrophages remove macromolecules, particles, debris, and microorganisms from the lymph stream. Lymphocytes and antibodies move through the walls of the sinuses and into the passing lymph, while dendritic cells pass from the lymph into the lymphatic follicles, carrying antigens from the body's epithelia and from infected tissues. In the cortical region of the lymph node, the sinuses wind around lymphatic follicles, which are ovoid germinal centers packed with differentiating and proliferating B lymphocytes and surrounded by loose T lymphocytes. Lymphocytes and antibodies also enter and exit blood capillaries throughout the lymph node. Lymph nodes are most numerous in the neck, mediastinum, abdominal mesenteries, pelvis, the proximal limbs (the axillae and the groin), and along the posterior abdominal wall. Inside the chest and trunk, lymph nodes tend to be found along the veins near viscera.
See also: node

lymph node

or

lymphatic node

a mass of lymphoid tissue, important in producing antibodies containing macrophages which remove foreign bodies from the lymph. It is present only in mammals and birds.

Lymph node

A small mass of tissue in the form of a knot or protuberance. Lymph nodes are the primary sources of lymph fluid, which serve in the body's defense by removing toxic fluids and bacteria.

lymph node

(limf nōd) [TA]
One of numerous round, oval, or bean-shaped bodies located along the course of lymphatic vessels, varying greatly in size and usually presenting a depressed area, the hilum.

lymph

a transparent, usually slightly yellow, often opalescent liquid found within the lymphatic vessels, and collected from tissues in most parts of the body and returned to the blood via the lymphatic system. It is about 95% water; the remainder consists of plasma proteins and other chemical substances contained in the blood plasma, but in a slightly smaller percentage than in plasma. Its cellular component consists chiefly of lymphocytes.

lymph duct
large vessels carrying lymph from smaller collecting vessels. Include thoracic duct, right lymphatic duct.
lymph heart
a muscular dilatation in a lymph vessel, capable of contraction and moving lymph along the vessel. Seen in embryos and lower vertebrates.
lymph node
any of the accumulations of lymphoid tissue organized as definite lymphoid organs along the course of lymphatic vessels, consisting of an outer cortical and an inner medullary part; they are the main source of lymphocytes of the peripheral blood and, as part of the reticuloendothelial system, serve as a defense mechanism by removing noxious agents, e.g. bacteria and toxins, and play a critical role in antibody formation. Sometimes called, incorrectly, lymph glands.
lymph node abscess
hard, usually cold swellings containing pus; secondary to primary lesion in node's drainage area; a feature of some chronic infections, e.g. tuberculosis, caseous lymphadenitis of sheep; specific nodes may cause specific syndromes, e.g. retropharyngeal nodes.
lymph node hyperplasia
increase in size due to increase in number of normal cells but with preservation of natal architecture.
lymph node hypoplasia
occurs in cattle and causes antenatal edema of the fetus, leading to dystocia in many cases. The calves are not viable.
lymph nodule
germinal centers in lymph nodes which produce lymphocytes. Called also lymphatic or lymphoid nodule.
periarteriolar lymph sheath (PALS)
the white pulp, heavily populated with T lymphocytes, that surrounds arteries in the spleen.
lymph tissue
see lymphoid tissue.

node

pl. nodi; a small mass of tissue in the form of a swelling, knot or protuberance, either normal or pathological.

node of Aschoff and Tawara
atrioventricular node.
cutaneous node
an elevated, solid lump, without a necrotic center, about 0.5 inch diameter, caused by acute or chronic inflammation, with an unbroken surface. Called also cutaneous nodule.
Flack's node
see sinoatrial node.
hemal n's
see hemal node.
Keith's node, Keith-Flack node
see sinoatrial node.
lymph node
see lymph node.
n's of Ranvier
constrictions of myelinated nerve fibers at regular intervals of about 1 mm at which the myelin sheath is absent and theaxon is enclosed only by Schwann cell processes.
sinoatrial (S-A) node
see sinoatrial node.
node of Tawara
atrioventricular node.

Patient discussion about lymph node

Q. tender protuding lymph node lump rt. arm pit aprox. 1/2" dia. any concerns or recommend treatment necessary?

A. lymph nodes can flare up any time you get infected in the armpit and all the area that it drains. i had it several times and it went away in the same manner that it came. i think that sometimes it caused because of a blockade done by deodorant. so i try to use this Chinese salt stone that doesn't contain aluminum.

More discussions about lymph node
References in periodicals archive ?
To be counted as a lymph node, the specimen had to be a capsule and subcapsular sinus; lymphoid aggregates lacking these architectural features were not counted as lymph nodes.
Specifically, ovarian cancer metastatic to the breast parenchyma can present as a focal mass without definite characteristic radiographic features (6); however, a few studies reveal that serous ovarian carcinoma metastatic to axillary lymph nodes can occasionally demonstrate a peripheral amorphous lymph node calcification pattern on a mammogram (7), which is related to psammoma body formation.
All 18 institutions processed all of the lymph node tissue rather than submitting representative sections.
This new technique will decrease OR time because the surgical team need not wait for pathology reports, decrease time under anaesthesia, and decrease unnecessary surgery on noncancerous lymph nodes.
Summary: Lymph nodes are part of the lymphatic system.
This project consisted of a retrospective study designed to analyze lymph node distribution in patients diagnosed with PTC who underwent a ND from 2000 to 2007 under the supervision of one surgeon (F.
Table 1: Result of gross examination of cattle lymph nodes Regional lymph nodes Number % Retropharyngeal 20 10.
Forgoing the standard practice of axillary node dissection when sentinel nodes reveal metastasis constitutes a practice change that "would improve clinical outcomes in thousands of women each year by reducing the complications associated with axillary lymph node dissection and improving quality of life with no diminution in survival," they concluded.
Of those, 30,000 have only one lymph node involvement.
Patient selection was based on CT findings showing mediastinal lymph node enlargement (>1 cm in short-axis dimension).