skin (skin) the outer protective covering of the body, consisting of the dermis (or corium) and the epidermis. 
skin
skin [skin]
)
Diagram of a cross-section of the skin.
elastic skin Ehlers-Danlos syndrome.
farmers' skin actinic elastosis.
lax skin , loose skin cutis laxa.
sailors' skin actinic elastosis.
skin (sk n)n. The membranous tissue forming an external protective covering or integument of an animal and consisting of the epidermis and dermis. v. To bruise, cut, or injure the skin of. skin  less adj. |
skin
Etymology: AS, scinn
the tough, supple cutaneous membrane that covers the entire surface of the body. It is composed of a thick layer of connective tissue called the dermis and an epidermis made of five layers of cells. Skin color varies according to the amount of melanin in the epidermis. Genetic differences determine the amount of melanin. The ultraviolet rays of the sun stimulate the production of melanin, which absorbs the rays and simultaneously darkens the skin. Modified skin continues into various parts of the body, such as mucous membrane, as in the lining of the vagina, the bladder, the lungs, the intestines, the nose, and the mouth. Mucous membrane lacks the heavily keratinized layer of the outside skin. The skin helps to cool the body when the temperature rises by radiating the heat of increased blood flow in expanded blood vessels and by providing a surface for the evaporation of sweat. When the temperature drops, the blood vessels constrict and the production of sweat diminishes. Also called cutaneous membrane, integument. See also dermis.
skin [skin]
the outer covering of the body. The skin is the largest organ of the body, and it performs a number of vital functions. It serves as a protective barrier against microorganisms. It helps shield the delicate, sensitive tissues underneath from mechanical and other injuries. It acts as an insulator against heat and cold, and helps eliminate body wastes in the form of perspiration. It guards against excessive exposure to the ultraviolet rays of the sun by producing a protective pigmentation, and it helps produce the body's supply of vitamin D. Its sense receptors enable the body to feel pain, cold, heat, touch, and pressure. The skin consists of two main parts: an outer layer, the epidermis, and an inner layer, the corium (or dermis).
Epidermis. The epidermis is thinner than the corium, and is made up of several layers of different kinds of cells. The number of cells varies in different parts of the body; the greatest number is in the palms of the hands and soles of the feet, where the skin is thickest.
The cells in the outer or horny layer of the epidermis are constantly being shed and replaced by new cells from its bottom layers in the lower epidermis. The cells of the protective, horny layer are nonliving and require no supply of blood for nourishment. As long as the horny outer layer remains intact, microorganisms cannot enter.
The cells in the outer or horny layer of the epidermis are constantly being shed and replaced by new cells from its bottom layers in the lower epidermis. The cells of the protective, horny layer are nonliving and require no supply of blood for nourishment. As long as the horny outer layer remains intact, microorganisms cannot enter.
Corium. Underneath the epidermis is the thicker part of the skin, the corium, or dermis, which is made up of connective tissue that contains blood vessels and nerves. It projects into the epidermis in ridges called papillae of the corium. The nerves that extend through the corium end in the papillae. The various skin sensations, such as touch, pain, pressure, heat, and cold, are felt through these nerves. The reaction to heat and cold causes the expansion and contraction of the blood capillaries of the corium. This in turn causes more or less blood to flow through the skin, resulting in greater or smaller loss of body heat (see temperature).
The sweat glands are situated deep in the corium. They collect fluid containing water, salt, and waste products from the blood and carry it away in canals that end in pores on the skin surface, where it is deposited as sweat. Perspiration helps regulate body temperature as well, because cooling of the skin occurs when sweat evaporates. The sebaceous glands are also in the corium. They secrete the oil that keeps the skin surface lubricated.
Beneath the corium is a layer of subcutaneous tissue. This tissue helps insulate the body against heat and cold, and cushions it against shock.
The hair and nails are outgrowths of the skin. The roots of the hair lie in follicles, or pockets of epidermal cells situated in the corium. Hair grows from the roots, but the hair cells die while still in the follicles, and the closely packed remains that are pushed upward form the hair shaft that is seen on the surface of the skin.
The nails grow in much the same way as the hair. The nail bed, like the hair root, is situated in the corium. The pink color of the nails is due to their translucent quality which allows the blood capillaries of the corium to show through.
The sweat glands are situated deep in the corium. They collect fluid containing water, salt, and waste products from the blood and carry it away in canals that end in pores on the skin surface, where it is deposited as sweat. Perspiration helps regulate body temperature as well, because cooling of the skin occurs when sweat evaporates. The sebaceous glands are also in the corium. They secrete the oil that keeps the skin surface lubricated.
Beneath the corium is a layer of subcutaneous tissue. This tissue helps insulate the body against heat and cold, and cushions it against shock.
The hair and nails are outgrowths of the skin. The roots of the hair lie in follicles, or pockets of epidermal cells situated in the corium. Hair grows from the roots, but the hair cells die while still in the follicles, and the closely packed remains that are pushed upward form the hair shaft that is seen on the surface of the skin.
The nails grow in much the same way as the hair. The nail bed, like the hair root, is situated in the corium. The pink color of the nails is due to their translucent quality which allows the blood capillaries of the corium to show through.
Normal skin. From Frazier et al., 2000.
skin test application of a substance to the skin, or intradermal injection of a substance, to permit observation of the body's reaction to it. Such a test detects a person's sensitivity to such allergens as dust and pollen, or to preparations of microorganisms believed to be the cause of a disorder.
There are several types of skin tests, including the patch test, the scratch test, and the intradermal test.
There are several types of skin tests, including the patch test, the scratch test, and the intradermal test.
Patch Test. This is the simplest type of skin test. A small piece of gauze or filter paper is impregnated with a minute quantity of the substance to be tested and is applied to the skin, usually on the forearm. After a certain length of time the patch is removed and the reaction observed. If there is no reaction, the test result is said to be negative; if the skin is reddened or swollen, the result is positive.
The patch test is used most often in testing for skin allergies, especially contact dermatitis.
The patch test is used most often in testing for skin allergies, especially contact dermatitis.
Scratch Test. In this test, one or more small scratches or superficial cuts are made in the skin, and a minute amount of the substance to be tested is inserted in the scratches and allowed to remain there for a short time. If no reaction has occurred after 30 minutes, the substance is removed and the test is considered negative. If there is redness or swelling at the scratch sites, the test is considered positive.
The scratch test is often used in testing for allergies. A complete screening for allergic sensitivity may require numerous skin tests. Only an extremely minute quantity of the substance can be used in each test since severe allergic reactions can occur.
The scratch test is also used in the diagnosis of tuberculosis. In Pirquet's reaction, for example, tuberculin is used, and the local inflammatory reaction that results is more marked in tuberculous persons than in normal ones.
The scratch test is often used in testing for allergies. A complete screening for allergic sensitivity may require numerous skin tests. Only an extremely minute quantity of the substance can be used in each test since severe allergic reactions can occur.
The scratch test is also used in the diagnosis of tuberculosis. In Pirquet's reaction, for example, tuberculin is used, and the local inflammatory reaction that results is more marked in tuberculous persons than in normal ones.
Intradermal Tests. In these tests, the substance under study is injected between the layers of skin. Intradermal tests are used for diagnosis of infectious diseases and determination of susceptibility to a disease or sensitivity to an allergen.
In the intradermal test for tuberculosis, the Mantoux test, a purified protein derivative (PPD), prepared from tubercle bacilli, is injected. In a positive result, the area becomes reddened or inflamed within 72 hours. This indicates past or present infection with or exposure to the tubercle bacillus. An infection that has been present for at least 2 to 8 weeks will usually be revealed by the test.
The Schick test is used to determine susceptibility to diphtheria. A very small dose of diphtheria antitoxin is injected into the forearm. In a positive reaction the area becomes red and remains so for about a week. If no reaction occurs, the person is immune to the disease.
The trichophytin test is sometimes used in diagnosing suspected cases of superficial fungus infection of the skin, such as ringworm. In the presence of infection by the fungus Trichophyton, an injection of trichophytin, which is prepared from cultures of the fungus, will produce a reaction similar to the tuberculin reaction. Skin tests, of course, are always made in an area separate from the infected area.
In addition to their frequent use in testing for allergies, intradermal tests are employed in the diagnosis of parasitic infections, such as schistosomiasis, other fungus diseases besides trichophytosis, and mumps.
In the intradermal test for tuberculosis, the Mantoux test, a purified protein derivative (PPD), prepared from tubercle bacilli, is injected. In a positive result, the area becomes reddened or inflamed within 72 hours. This indicates past or present infection with or exposure to the tubercle bacillus. An infection that has been present for at least 2 to 8 weeks will usually be revealed by the test.
The Schick test is used to determine susceptibility to diphtheria. A very small dose of diphtheria antitoxin is injected into the forearm. In a positive reaction the area becomes red and remains so for about a week. If no reaction occurs, the person is immune to the disease.
The trichophytin test is sometimes used in diagnosing suspected cases of superficial fungus infection of the skin, such as ringworm. In the presence of infection by the fungus Trichophyton, an injection of trichophytin, which is prepared from cultures of the fungus, will produce a reaction similar to the tuberculin reaction. Skin tests, of course, are always made in an area separate from the infected area.
In addition to their frequent use in testing for allergies, intradermal tests are employed in the diagnosis of parasitic infections, such as schistosomiasis, other fungus diseases besides trichophytosis, and mumps.
skin,
n the tough, supple cutaneous membrane that covers the entire surface of the body. It is the largest organ of the body and is composed of five layers of cells in the epidermis, which overlies the dermis. See also stratum.
skin
the outer covering and largest organ of the body. It serves as a protective barrier against microorganisms, helps shield delicate tissues underneath from mechanical and other injuries, insulates against heat and cold, and helps eliminate body wastes. It guards against ultraviolet radiation by producing a protective pigment and it helps produce vitamin D. Its sense receptors detect pain, cold, heat, touch and pressure.
The skin consists of an outer cellular, avascular epidermis, and an inner fibrous corium (dermis, true skin) resting upon a hypodermis of fat and panniculus muscle.
See also cutaneous, epidermal, epidermis.
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Basic structure of the skin. By permission from McCurnin D, Poffenbarger EM, Small Animal Physical Diagnosis and Clinical Procedures, Saunders, 1991
skin appendages
skin-associated lymphoid tissues (SALT)
see skin-associated lymphoid tissue.
autoimmune skin disease
skin biopsy
removal of a small section of skin for histopathological examination. See also keyes punch.
skin cancer
include squamous cell carcinoma, papilloma and fibropapilloma, intracutaneous cornifying epithelioma (keratoacanthoma), basal cell tumors and tumors of the adnexa, perianal gland and hair follicles.
congenital absence of skin
see epitheliogenesis imperfecta.
skin depigmentation
see hypopigmentation.
skin emphysema
see subcutaneous emphysema.
skin fold thickness
a measure of obesity in humans but not a valid indicator in dogs or cats as the skin lifts off the subcutaneous tissue.
skin fungal infection
skin gangrene
death of tissue and usually involves dermis, epidermis and subcutaneous tissue, e.g. severe saddle galls, heat burns, chemical burns, Claviceps purpurea poisoning. The affected area is cold and bluish in color. This changes to black and the area begins to lift at the edges and to dry out.
skin inflammation
see dermatitis.
skin leukosis
occurs in marek's disease. Called also cutaneous lymphosarcoma.
skin-maggot fly
see cordylobiaanthropophaga.
skin memory
see mnemodermia.
skin receptor
cutaneous sensory endorgans.
skin resiliency test
see skin tenting test (below).
skin tag
see fibrovascular papilloma.
skin tension lines
see tension line.
skin tenting test
a fold of skin is picked up and then quickly let go. The amount that it will stretch is an indication of its extensibility. The speed with which it returns to a normal position is determined by the degree of hydration of the skin and subcutaneous tissue and the amount of fat in the subcutaneous tissue, e.g. in an animal that is 10 to 12% dehydrated the skin fold will not disappear until 20 to 45 seconds have elapsed.
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Tenting of the skin in a dehydrated cow. By permission from Blowey RW, Weaver AD, Diseases and Disorders of Cattle, Mosby, 1997
skin test
application or intradermal injection of a substance to the skin to test the body's reaction to it. Such a test detects an animal's sensitivity to such allergens as dust and pollen, or to preparations of microorganisms believed to be the cause of a disorder.
There are several types of skin tests, including the patch test, the scratch test, and the intradermal test.
skin wool
scoured wool from a fellmonger.
skin
Vox populi adjective Cutaneous noun Anatomy Cutis The outer integument of the body which consists of epidermis and dermis, the latter of which rests on subcutaneous tissue. See Aging skin, Artificial skin, Blue skin, Cigarette-paper skin, Composite cultured skin, Diamond skin, Elephant skin, Glossy skin, Harlequin skin, Hide-bound skin, Leopard skin, Lizard skin, Moleskin, Moroccan leather skin, Paper money skin, Red skin, Sandpaper skin, Second
Skin®, Spray-on skin, Swiss cheese skin, Washerwoman skin.
Patient discussion about skin.
Q. is it dangerouse to stay in the sun even if you don't get burned? how bad is it if you only get a little tan? does it matter what is your skin type in the first place? is only getting burned dangerouse, or being in the sun alltogether?
A. It depends on skin type.
White skins are more prone to freckles and sunburn, and even worse, skin cancer than those who have darker skins. Most skin cancer patients are white-skinned.
Melanin, responsible for darkening of our skin. It is more dominant on people with darker skin than whiter skin. If the skin has high melanin content, they are less prone to have skin cancer.
It is not the sun who directly causes our skin to darken but the melanin. Melanin multiplies when we are exposed to sun.
By the way, this info doesn't intend to terrify white-skinned people but to be aware of our skin. We must take care of our largest organ in our body because it serves as a protection our inner organs.
White skins are more prone to freckles and sunburn, and even worse, skin cancer than those who have darker skins. Most skin cancer patients are white-skinned.
Melanin, responsible for darkening of our skin. It is more dominant on people with darker skin than whiter skin. If the skin has high melanin content, they are less prone to have skin cancer.
It is not the sun who directly causes our skin to darken but the melanin. Melanin multiplies when we are exposed to sun.
By the way, this info doesn't intend to terrify white-skinned people but to be aware of our skin. We must take care of our largest organ in our body because it serves as a protection our inner organs.
Q. How can you know if a mole is a skin cancer or not? I'm only 15, but I’ve had this small thing on my right shoulder for a reeeeaaaally long time. It's the same color as my skin. It’s smaller than the head of a pencil eraser, perfectly round, and its smooth. I've never worried about it seriously, until about a week ago, when I read an article in a magazine about skin cancer. Even then I wouldn't have worried about it, because It didn't really match any of the symptoms, except one. It did bleed once about 2 1/2 years ago. And it said bleeding was a big sign I don't know, what do you think? And please try and say something other than," go have it checked out". Because I currently have no insurance. Thanks :]
A. First off; you should know about what dermatologists call the ABCDE's of skin cancer.
A: Asymetrical. If you draw an imaginary line through it, doe both sides appear to be mirror images of each other?
B: Borders. Does the mole have irregular, jagged, or rough borders?
C: Color: Is is dark; especially black or grey or blue and has it changed colors?
D: Diameter. Is it bigger than the tip of a pencil eraser?
E: Evolving. Has any of the preceding A,B,C, or D's changed?
Ask yourself or a loved one to run those tests on it. And as had been previously said; make an appointment with your dermatologist. They would be happy to remove any moles that may be suspisious or unsightly and determine if it is cancerous or not. Milian is right; a mere month can be the difference between life and death. Melanoma is deadly. Be smart and stay safe. Hope this helped.
A: Asymetrical. If you draw an imaginary line through it, doe both sides appear to be mirror images of each other?
B: Borders. Does the mole have irregular, jagged, or rough borders?
C: Color: Is is dark; especially black or grey or blue and has it changed colors?
D: Diameter. Is it bigger than the tip of a pencil eraser?
E: Evolving. Has any of the preceding A,B,C, or D's changed?
Ask yourself or a loved one to run those tests on it. And as had been previously said; make an appointment with your dermatologist. They would be happy to remove any moles that may be suspisious or unsightly and determine if it is cancerous or not. Milian is right; a mere month can be the difference between life and death. Melanoma is deadly. Be smart and stay safe. Hope this helped.
Q. Is psoriasis contagious? My wife got psoriasis and I don’t want to get infected…
A. No, psoriasis is not contagious. It is not something you can "catch" or "pass on." The psoriatic lesions may not look good, but they are not infections or open wounds. People with psoriasis pose no threat to the health or safety of others.
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