tissue (redirected from critical tissue)

tissue /tis·sue/ (tish´u) an aggregation of similarly specialized cells which together perform certain special functions.

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adenoid tissue  lymphoid t.

adipose tissue  connective tissue made of fat cells in meshwork of areolar tissue.

areolar tissue  connective tissue made up largely of interlacing fibers.

bony tissue  bone.

brown adipose tissue  a thermogenic type of adipose tissue containing a dark pigment, and arising during embryonic life in certain specific areas in many mammals, including humans; it is prominent in the newborn.

cancellous tissue  the spongy tissue of bone.

cartilaginous tissue  the substance of cartilage.

chromaffin tissue  a tissue composed largely of chromaffin cells, well supplied with nerves and vessels; it occurs in the adrenal medulla and also forms the paraganglia of the body.

cicatricial tissue  the dense fibrous tissue forming a cicatrix, derived directly from granulation tissue.

connective tissue  the stromatous or nonparenchymatous tissues of the body; that which binds together and is the ground substance of the various parts and organs of the body.

elastic tissue , elastic tissue, yellow connective tissue made up of yellow elastic fibers, frequently massed into sheets.

endothelial tissue  endothelium.

epithelial tissue  epithelium.

erectile tissue  spongy tissue that expands and becomes hard when filled with blood.

extracellular tissue  the total of tissues and body fluids outside the cells.

fatty tissue  adipose t.

fibrous tissue  the common connective tissue of the body, composed of yellow or white parallel fibers.

gelatinous tissue  mucous t.

glandular tissue  an aggregation of epithelial cells that elaborate secretions.

granulation tissue  the newly formed vascular tissue normally produced in healing of wounds of soft tissue, ultimately forming the cicatrix.

gut-associated lymphoid tissue  (GALT) lymphoid tissue associated with the gut, including the tonsils, Peyer's patches, lamina propria of the gastrointestinal tract, and appendix.

indifferent tissue  undifferentiated embryonic tissue.

interstitial tissue  connective tissue between the cellular elements of a structure.

lymphadenoid tissue  tissue resembling that of lymph nodes, found in the spleen, bone marrow, tonsils, and other organs.

lymphoid tissue  a latticework of reticular tissue, the interspaces of which contain lymphocytes.

mesenchymal tissue  mesenchyme.

mucous tissue  a jellylike connective tissue, as occurs in the umbilical cord.

muscle tissue , muscular tissue the substance of muscle, consisting of muscle fibers, muscle cells, connective tissue, and extracellular material.

myeloid tissue  red bone marrow.

nerve tissue , nervous tissue the specialized tissue making up the central and peripheral nervous systems, consisting of neurons with their processes, other specialized or supporting cells, and extracellular material.

osseous tissue  the specialized tissue forming the bones.

reticular tissue , reticulated tissue connective tissue consisting of reticular cells and fibers.

scar tissue  cicatricial t.

sclerous tissues  the cartilaginous, fibrous, and osseous tissue.

skeletal tissue  the bony, ligamentous, fibrous, and cartilaginous tissue forming the skeleton and its attachments.

subcutaneous tissue  the layer of loose connective tissue directly under the skin.

white adipose tissue , yellow adipose tissue the adipose tissue comprising the bulk of the body fat.

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tis·sue (tsh)

n.

An aggregation of morphologically similar cells and associated intercellular matter acting together to perform specific functions in the body. There are four basic types of tissue: muscle, nerve, epithelial, and connective.

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tissue

[tish′o̅o̅]

Etymology: Fr, tissu, fabric

a collection of similar cells in a matrix acting together to perform a particular function.

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tissue [tish´u]

a group or layer of similarly specialized cells that together perform certain special functions.

adenoid tissue lymphoid tissue.

adipose tissue connective tissue made of fat cells in a meshwork of areolar tissue.

areolar tissue connective tissue made up largely of interlacing fibers.

bony tissue osseous tissue.

brown adipose tissue (brown fat tissue) brown fat.

bursa-equivalent tissue (bursal equivalent tissue) a hypothesized lymphoid tissue in nonavian vertebrates including human beings, equivalent to the bursa of Fabricius in birds: the site of B lymphocyte maturation. It now appears that B lymphocyte maturation occurs primarily in the bone marrow.

cancellous tissue the spongy tissue of bone.

cartilaginous tissue the substance of cartilage.

chordal tissue the tissue of the notochord.

chromaffin tissue a tissue composed largely of chromaffin cells, well supplied with nerves and vessels; it occurs in the adrenal medulla and also forms the paraganglia of the body.

cicatricial tissue the dense fibrous tissue forming a cicatrix, derived directly from granulation tissue; called also scar tissue.

connective tissue the tissue that binds together and is the support of the various structures of the body; see also connective tissue.

elastic tissue connective tissue made up of yellow elastic fibers, frequently massed into sheets.

endothelial tissue peculiar connective tissue lining serous and lymph spaces.

epithelial tissue a general name for tissues not derived from the mesoderm.

erectile tissue spongy tissue that expands and becomes hard when filled with blood.

fatty tissue connective tissue made of fat cells in a meshwork of areolar tissue.

fibrous tissue the common connective tissue of the body, composed of yellow or white parallel elastic and collagen fibers.

gelatinous tissue mucous tissue.

granulation tissue material formed in repair of wounds of soft tissue, consisting of connective tissue cells and ingrowing young vessels; it ultimately forms cicatrix.

gut-associated lymphoid tissue (GALT) lymphoid tissue associated with the gut, including the tonsils, Peyer's patches, lamina propria of the gastrointestinal tract, and appendix.

indifferent tissue undifferentiated embryonic tissue.

interstitial tissue connective tissue between the cellular elements of a structure.

lymphadenoid tissue tissue resembling that of lymph nodes, spleen, bone marrow, tonsils, and lymph vessels.

lymphoid tissue a latticework of reticular tissue whose interspaces contain lymphocytes.

mesenchymal tissue embryonic connective tissue composed of stellate cells and a ground substance of coagulable fluid.

mucous tissue a jellylike connective tissue, such as occurs in the umbilical cord. Called also gelatinous tissue.

muscular tissue the substance of muscle.

myeloid tissue red bone marrow.

nerve tissue (nervous tissue) the specialized tissue forming the elements of the nervous system.

osseous tissue the specialized tissue forming the bones.

reticular tissue (reticulated tissue) connective tissue composed predominantly of reticulum cells and reticular fibers.

scar tissue cicatricial tissue.

sclerous t's the cartilaginous, fibrous, and osseous tissues.

skeletal tissue the bony, ligamentous, fibrous, and cartilaginous tissue forming the skeleton and its attachments.

splenic tissue red pulp.

subcutaneous tissue the layer of loose connective tissue directly under the skin.

tissue typing identification of tissue types for purposes of predicting acceptance or rejection of grafts and transplants. The process and purposes of tissue typing are essentially the same as for blood typing. The major difference lies in the kinds of antigens being evaluated. The acceptance of allografts depends on the hla antigens (HLA); if the donor and recipient are not HLA identical, the allograft is rejected, sometimes within minutes. The HLA genes are located in the major histocompatibility complex, a region on the short arm of chromosome 6, and are involved in cell-cell interaction, immune response, organ transplantation, development of cancer, and susceptibility to disease. There are five genetic loci, designated HLA-A, HLA-B, HLA-C, HLA-D, and HLA-DR. At each locus, there can be any of several different alleles.



Each person inherits one chromosome 6 from the mother and one from the father; that is, each parent transmits to the child one allele for each kind of antigen (A, B, C, D, and DR). If the parents are different at both alleles of a locus, the statistical chance of one sibling being identical to another is one in four (25 per cent), the chance of being identical at one allele only (half-identical) is 50 per cent, and the chance of a total mismatch is 25 per cent.

Techniques for Tissue Typing. Histocompatibility testing involves several basic methods of assay for HLA differences. The most widely used method uses the polymerase chain reaction to compare the DNA of the person, organ, or graft being tested with known pieces of the genes encoding MHC antigens. The variability of these regions of the genes determines the tissue type of the subject.



Serologic methods are used to detect serologically defined antigens on the surfaces of cells. In general, HLA-A, -B, and -C determinants are primarily measured by serologic techniques. A second method, involving lymphocyte reactivity in a mixed lymphocyte culture, for determining HLA-D or lymphocyte-defined antigens, is now only rarely used.

Essentially, the serologic method is performed by incubating target lymphocytes (isolated from fresh peripheral blood) with antisera that recognize all known HLA antigens. The cells are spread in a tray with microscopic wells containing various kinds of antisera and are incubated for 30 minutes, followed by an additional 60-minute complement incubation. If the lymphocytes have on their surfaces antigens recognized by the antibodies in the antiserum, the lymphocytes are lysed. A dye is added to show changes in the permeability of the cell membrane and cellular death. The proportion of cells destroyed by lysis indicates the degree of histologic incompatibility. If, for example, the lymphocytes from a person being tested for HLA-A3 are destroyed in a well containing antisera for HLA-A3, the test is positive for this antigen group.

white adipose tissue (yellow adipose tissue) the adipose tissue composing the bulk of the body fat.

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tissue (tish´oo),

n an aggregation of similarly specialized cells united in the performance of a particular function.

tissue adhesives,

n agents or materials that may be used to seal two cut tissue surfaces together or cover a surgically exposed surface such as butyl cyanoacrylate, which is used to cover palatal donor sites in periodontal surgery.

tissue, compression of,

n See tissue displaceability.

tissue conditioning,

n a disciplined program of patient-performed plaque control measures designed for gingiva that is soft, spongy, and bleeds easily from poor oral hygiene habits, in order to improve gingival health before subgingival scaling is performed.

tissue, connective,

n the binding and supportive tissue of the body; derived from the mesoderm; depending on its location and function, it is composed of fibroblasts, primitive mesenchymal cells, collagen fibers, and elastic fibers, with associated blood and lymphatic vessels and nerve fibers.

tissue, critical,

n tissue that reacts most unfavorably to radiation or by its nature attracts and absorbs specific radiochemicals.

tissue displaceability,

n the quality of oral tissues that permits them to be placed in or assume other positions than their relaxed position.

tissue displacement,

n change in the form or position of tissues as a result of pressure.

tissue, engineering,

n the interdisciplinary field that uses life science and engineering principles in the development of biologic substitutes for tissue restoration or replacement.

tissue, flabby,

n See tissue, hyperplastic.

tissue, hyperplastic,

n in dentistry, excessively movable tissue about the mandible or maxillae resulting from increases in the number of normal cells.

tissue, interdental,

n the gingivae, cementum of the teeth, free gingival and transseptal fibers of the periodontal membrane (ligament), and alveolar and supporting bone.

tissue molding,

n See border molding.

tissue, peripheral,

n See border structures.

tissue, redundant,

n See epulis fissuratum.

tissue sloughing,

n a surface layer of flesh peeling away. Possible causes are extensive exposure to topical anesthetic, overly abrasive toothpaste, smokeless tobacco, tissue burn, or mouthrinses. Also called
epithelial desquamation.

tissue, subjacent,

n the structures that underlie or are in border contact with a denture base; they may or may not have a supporting relationship to the overlying base.

tissue-borne partial denture,

n See denture, partial, tissue-borne.

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tissue

a group or layer of similarly specialized cells that together perform certain special functions. For anatomically specific tissues see under their identifying titles, e.g. adipose, connective.

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tissue death

see necrosis.

tissue density

the penetrability of tissue by x-rays, bone and tooth being most dense, blood and soft tissue the next, fat the next, and gas and air least.

tissue edema

an abnormal accumulation of tissue fluid.

tissue factor

see tissue thromboplastin.

tissue fluid

the extracellular fluid that constitutes the environment of the body cells. It is low in protein, is formed by filtration through the capillaries, and the excess drains away as lymph. See also interstitial fluid.

tissue inhibitors

inhibitors of fibrinolysis; present in placenta.

indifferent tissue

undifferentiated embryonic tissue.

tissue necrosis fever

fever caused by pyrogens released by necrotic pyrogens.

tissue plasminogen activator

see plasminogen activator.

tissue reacting agent

substances that have a poorly defined but advantageous local effect on tissues.

tissue receptor site

a cell receptor common to cells of a particular tissue.

tissue residue

residues of chemical substances that are unacceptable to local pure food legislation especially sulfonamides, estrogens, chlorinated hydrocarbons, heavy metals. These are thought or known to have a deleterious effect on people eating or drinking the relevant animal product. See also chemical food residue.

tissue sensitivity

the susceptibility of individual tissues to injury by x-ray. The injury may be by way of inflammation, necrosis or cessation of cell growth. Fast-growing tissues in which the cells have a high mitotic index are the most sensitive, especially gonads, germinative layer of skin and erythropoietic tissues.

supportive t's

cartilage and bone.

tissue therapy

see glandular therapy.

tissue typing

identification of tissue types for purposes of predicting acceptance or rejection of grafts and organ transplants. The process and purposes of tissue typing are essentially the same as for blood typing. The major difference lies in the kinds of antigens being evaluated. White blood cells, particularly lymphocytes, are used for tissue typing. The acceptance of allografts depends particularly on the matching of MHC antigens. If the donor and recipient are not MHC identical, the allograft is rejected. See also typing.

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tissue

A basic anatomical and physiological component of the living organism, consisting of a collection of similar cells and their intercellular substances. Examples: connective tissue, epithelial tissue, muscular tissue, nervous tissue.

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tissue

A group of similar cells and stroma, which perform a specific function. See Adipose tissue, Bronchiole-associated lymphoid tissue, Chromaffin tissue, Connective tissue, Granulation tissue, Gut-associated lymphoid tissue, Mucosa-related lymphoid tissue, Skin-associated lymphoid tissue, Soft tissue.

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Patient discussion about tissue.

Q. My neighbor's kid had a lens dislocation due to Marfan's disease. Is this a contagious thing? My neighbor's have a sweet 8 year old boy. he had a lens dislocation due to a connective tissue disease named Marfan (I think that the name). It sounds like a very serious condition. My boy is playing with this kid several hour a week. should I take him to the GP to see that his is not infected with this marfan thing?

A. Don't worry. Marfan's syndrome is a connective tissue disease that is genetic. This means that You can't "get" this disease. Either you are borne with it or you will never suffer from it.
lens dislocation is a known symptom of marfan's syndrome, and is not connected to infectious diseases.

Q. I could feel hard tissues in my breasts.I suspect it the other way, any idea what it may be? I could feel hard tissues in my breasts. While reading article about breast cancer, I happened to note that these may be simple cyst and there is nothing to worry. My friend too had cyst and treated by the doctor with needle by removing the fluid out. But I suspect it the other way, any idea what it may be?

A. you cannot just guess it, I do encourage you to go see your doctor (oncologist is recommended), to have your breast checked.
first, your doctor will have a physical examination on you, and then it might help to find the correct diagnose by using some imaging procedures (ultrasound, mammography), or even by doing a fine needle aspiration on the lump. then it will be checked under microscopes to get the specific "what is that lump?"

Q. I want to get cure for asthma and develop my cardiac tissue. What is the best exercise for me to do? This is Daron, 20/m. I have had asthma since I was 3 yrs old, and suffer from exercise induced asthma as well as weather and food. Running is the worst thing that induces asthma in me. I want to get cure for asthma and develop my cardiac tissue to ensure fitness. What is the best exercise for me to do? I will be very thankful if I get suitable suggestion or advice..

A. daron,their is no cure for asthma--asthma is controlled by meds--if you dont have one get a pulmonary DR.--you can try riding a bike,and walking,i was born with asthma and i have the same problem as you,--you can try walking or biking for a little amount of time each day,--you can also try taking your meds before doing any exercize,THere are meds on the market,that can help you to do the things that you like.--mrfoot56---peace