Small, sacculated organs found within the DERMIS. Each gland has a single duct that emerges from a cluster of oval alveoli. Each alveolus consists of a transparent BASEMENT MEMBRANE enclosing epithelial cells. The ducts from most sebaceous glands open into a HAIR FOLLICLE, but some open on the general surface of the SKIN. Sebaceous glands secrete SEBUM.

Sebaceous gland neoplasms are uncommon cutaneous tumors that originate from the sebaceous glands, which can be benign (e.g., seborrheic keratosis, syringoma, trichofolliculoma) or malignant (e.g., sebaceous carcinoma, sebaceomatosis, mucoepidermoid carcinoma).

The oily substance secreted by SEBACEOUS GLANDS. It is composed of KERATIN, fat, and cellular debris.

Diseases of the sebaceous glands such as sebaceous hyperplasia and sebaceous cell carcinoma (SEBACEOUS GLAND NEOPLASMS).

A chronic disorder of the pilosebaceous apparatus associated with an increase in sebum secretion. It is characterized by open comedones (blackheads), closed comedones (whiteheads), and pustular nodules. The cause is unknown, but heredity and age are predisposing factors.

A malignant tumor composed of cells showing differentiation toward sebaceous epithelium. The tumor is solitary, firm, somewhat raised, more or less translucent, and covered with normal or slightly verrucose epidermis. It may be yellow or orange. The face and scalp are the commonest sites. The growth can be slow or rapid but metastasis is uncommon. Surgery cures most of the cases. (From Rook et al., Textbook of Dermatology, 4th ed, pp2403-4)

A tube-like invagination of the EPIDERMIS from which the hair shaft develops and into which SEBACEOUS GLANDS open. The hair follicle is lined by a cellular inner and outer root sheath of epidermal origin and is invested with a fibrous sheath derived from the dermis. (Stedman, 26th ed) Follicles of very long hairs extend into the subcutaneous layer of tissue under the SKIN.

Large, branched, specialized sweat glands that empty into the upper portion of a HAIR FOLLICLE instead of directly onto the SKIN.

The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of EPITHELIUM: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis).

Absence of hair from areas where it is normally present.

Glands that secrete SALIVA in the MOUTH. There are three pairs of salivary glands (PAROTID GLAND; SUBLINGUAL GLAND; SUBMANDIBULAR GLAND).

A filament-like structure consisting of a shaft which projects to the surface of the SKIN from a root which is softer than the shaft and lodges in the cavity of a HAIR FOLLICLE. It is found on most surfaces of the body.

The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.

Sweat-producing structures that are embedded in the DERMIS. Each gland consists of a single tube, a coiled body, and a superficial duct.

MAMMARY GLANDS in the non-human MAMMALS.

Simple sweat glands that secrete sweat directly onto the SKIN.

The sebaceous glands situated on the inner surface of the eyelids between the tarsal plates and CONJUNCTIVA.

Glands of external secretion that release its secretions to the body's cavities, organs, or surface, through a duct.

One of two salivary glands in the neck, located in the space bound by the two bellies of the digastric muscle and the angle of the mandible. It discharges through the submandibular duct. The secretory units are predominantly serous although a few mucous alveoli, some with serous demilunes, occur. (Stedman, 25th ed)

Neoplasms composed of sebaceous or sweat gland tissue or tissue of other skin appendages. The concept does not refer to neoplasms located in the sebaceous or sweat glands or in the other skin appendages.

The outer covering of the calvaria. It is composed of several layers: SKIN; subcutaneous connective tissue; the occipitofrontal muscle which includes the tendinous galea aponeurotica; loose connective tissue; and the pericranium (the PERIOSTEUM of the SKULL).

The functions of the skin in the human and animal body. It includes the pigmentation of the skin.

The outer covering of the body composed of the SKIN and the skin appendages, which are the HAIR, the NAILS; and the SEBACEOUS GLANDS and the SWEAT GLANDS and their ducts.

A chronic inflammatory disease of the skin with unknown etiology. It is characterized by moderate ERYTHEMA, dry, moist, or greasy (SEBACEOUS GLAND) scaling and yellow crusted patches on various areas, especially the scalp, that exfoliate as dandruff. Seborrheic dermatitis is common in children and adolescents with HIV INFECTIONS.

An increase in the number of cells in a tissue or organ without tumor formation. It differs from HYPERTROPHY, which is an increase in bulk without an increase in the number of cells.

Tumors of cancer of the EYELIDS.

The largest of the three pairs of SALIVARY GLANDS. They lie on the sides of the FACE immediately below and in front of the EAR.

A family of G-protein-coupled receptors that have specificity for MELANOCYTE-STIMULATING HORMONES and ADRENOCORTICOTROPIC HORMONE. There are several subtypes of melanocortin receptors, each having a distinct ligand specificity profile and tissue localization.

'Skin diseases' is a broad term for various conditions affecting the skin, including inflammatory disorders, infections, benign and malignant tumors, congenital abnormalities, and degenerative diseases, which can cause symptoms such as rashes, discoloration, eruptions, lesions, itching, or pain.

Transmembrane proteins belonging to the tumor necrosis factor superfamily that play an essential role in the normal development of several ectodermally derived organs. Several isoforms of the ectodysplasins exist due to multiple ALTERNATIVE SPLICING of the MRNA for the protein. The isoforms ectodysplasin A1 and ectodysplasin A2 are considered biologically active and each bind distinct ECTODYSPLASIN RECEPTORS. Genetic mutations that result in loss of function of ectodysplasin result in ECTODERMAL DYSPLASIA 1, ANHIDROTIC.

A topical dermatologic agent that is used in the treatment of ACNE VULGARIS and several other skin diseases. The drug has teratogenic and other adverse effects.

A benign, non-neoplastic, usually self-limiting epithelial lesion closely resembling squamous cell carcinoma clinically and histopathologically. It occurs in solitary, multiple, and eruptive forms. The solitary and multiple forms occur on sunlight exposed areas and are identical histologically; they affect primarily white males. The eruptive form usually involves both sexes and appears as a generalized papular eruption.

Diseases affecting the orderly growth and persistence of hair.

Epidermal cells which synthesize keratin and undergo characteristic changes as they move upward from the basal layers of the epidermis to the cornified (horny) layer of the skin. Successive stages of differentiation of the keratinocytes forming the epidermal layers are basal cell, spinous or prickle cell, and the granular cell.

Cell surface receptors that bind CORTICOTROPIN; (ACTH, adrenocorticotropic hormone) with high affinity and trigger intracellular changes. Pharmacology suggests there may be multiple ACTH receptors. An ACTH receptor has been cloned and belongs to a subfamily of G-protein-coupled receptors. In addition to the adrenal cortex, ACTH receptors are found in the brain and immune systems.

De novo fat synthesis in the body. This includes the synthetic processes of FATTY ACIDS and subsequent TRIGLYCERIDES in the LIVER and the ADIPOSE TISSUE. Lipogenesis is regulated by numerous factors, including nutritional, hormonal, and genetic elements.

A circumscribed benign epithelial tumor projecting from the surrounding surface; more precisely, a benign epithelial neoplasm consisting of villous or arborescent outgrowths of fibrovascular stroma covered by neoplastic cells. (Stedman, 25th ed)

A salivary gland on each side of the mouth below the TONGUE.

The scientific discipline concerned with the physiology of the nervous system.

An unctuous substance composed of sebum and desquamated epithelial cells, which covers the skin of the fetus.

Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)

Eyelid diseases refer to various medical conditions that affect the function, structure, or appearance of the eyelids, including inflammatory, infectious, neoplastic, congenital, and traumatic disorders, which can impact vision, comfort, and overall ocular health.

The hairs which project from the edges of the EYELIDS.

A class of fibrous proteins or scleroproteins that represents the principal constituent of EPIDERMIS; HAIR; NAILS; horny tissues, and the organic matrix of tooth ENAMEL. Two major conformational groups have been characterized, alpha-keratin, whose peptide backbone forms a coiled-coil alpha helical structure consisting of TYPE I KERATIN and a TYPE II KERATIN, and beta-keratin, whose backbone forms a zigzag or pleated sheet structure. alpha-Keratins have been classified into at least 20 subtypes. In addition multiple isoforms of subtypes have been found which may be due to GENE DUPLICATION.

Highly keratinized processes that are sharp and curved, or flat with pointed margins. They are found especially at the end of the limbs in certain animals.

An order of ungulates having an odd number of toes, including the horse, tapir, and rhinoceros. (Dorland, 27th ed)

Cytoplasmic filaments intermediate in diameter (about 10 nanometers) between the microfilaments and the microtubules. They may be composed of any of a number of different proteins and form a ring around the cell nucleus.

Cold-blooded, air-breathing VERTEBRATES belonging to the class Reptilia, usually covered with external scales or bony plates.

A keratin subtype that includes keratins that are generally larger and less acidic that TYPE I KERATINS. Type II keratins combine with type I keratins to form keratin filaments.