Medical terms - Letter D (page 4) | MedicalVocabulary.org

Dementia complex, AIDS

See: AIDS dementia complex
Dementia, hereditary multi-infarct

See CADASIL
Dementia, MELAS

Dementia, MELAS: MELAS is the acronym for Mitochondrial Encephalopathy, Lactic Acidosis, and Strokelike episodes. MELAS is a form of dementia. It is caused by mutations in the genetic material (DNA) in the mitochondria…
Dementia, multi-infarct

See Vascular dementia
Dementia, vascular

See Vascular dementia
Demonophobia

An abnormal and persistent fear of evil supernatural beings in persons who believe such beings exist and roam freely to cause harm. Those who suffer from this phobia realize their fear is excessive or irrational…
Demulcent

Soothing. The word 'demulcent' comes from the Latin verb, 'demulcere' meaning 'to caress.' Something that is demulcent is caressing. The term 'demulcent' refers to an agent, such as an oil, that forms a soothing film…
Demyelination

A degenerative process that erodes away the myelin sheath that normally protects nerve fibers. Demyelination exposes these fibers and appears to cause problems in nerve impulse conduction that may affect many physical…
Dendrite

A short arm-like protuberance from a nerve cell (a neuron). Dendrites from neurons next to one another are tipped by synapses (tiny transmitters and receivers for chemical messages between the cells). The word…
Dendritic

Referring to a dendrite, a short arm-like protuberance from a nerve cell (a neuron). Dendrites from neurons next to one another are tipped by synapses (tiny transmitters and receivers for chemical messages between the…
Dendritic cell

A special type of cell that is a key regulator of the immune system, acting as a professional antigen-presenting cell (APC) capable of activating naïve T cells and stimulating the growth and differentiation of B cells…
Denervate

To deprive of the nerve supply. Denervate is the opposite of innervate
Denervation

Loss of nerve supply. There are many causes of denervation. Denervation may be due to a disease as, for example, in polio where the death of motor neurons causes the denervation of muscle fibers. Denervation may be due…
Dengue

Also known as Dengue fever, an acute mosquito-borne viral illness of sudden onset that usually follows a benign course with headache, fever, prostration, severe joint and muscle pain, swollen glands (lymphadenopathy)…
Dengue fever

Dengue fever: An acute mosquito- borne viral illness of sudden onset that usually follows a benign course with headache, fever, prostration, severe joint and muscle pain, swollen glands (lymphadenopathy) and rash. The…
Dengue hemorrhagic fever (DHF)

Fever (DHF): A syndrome due to the dengue virus that tends to affect children under 10, causing abdominal pain, hemorrhage (bleeding) and circulatory collapse (shock). DHF starts abruptly with high continuous fever and…
Dengue shock syndrome

A syndrome due to the dengue virus that tends to affect children under 10, causing abdominal pain, hemorrhage (bleeding) and circulatory collapse (shock). Known also as dengue hemorrhagic fever (DHF), it starts abruptly…
Dental and Craniofacial Research, National Inst.

E of (NIDCR): One of the National Institutes of Health (NIH) in the U.S., the NIDCR is for dental and other craniofacial diseases. NIDCR's mission is, in formal terms, to 'provide leadership for a national research…
Dental Association, American (ADA)

The mission statement of the ADA reads as follows: 'The ADA is the professional association of dentists dedicated to serving both the public and the profession of dentistry. The ADA promotes the public's health through…
Dental braces (orthodontics)

Dental braces (orthodontics): The use of devices to move teeth or adjust underlying bone. The ideal age for starting orthodontic treatment is between ages 3 to 12 years. Temporomandibular joint (TMJ) problems can be…
Dental drill

A device that dentists use to drill into teeth. Primitive dental drills were used in the 18th and early 19th centuries. In 1868, American dentist George F. Green added power to the drill with a pneumatic version run by…
Dental impaction

Teeth pressing together. For example, molar teeth (the large teeth in the back of the jaw) can be impacted, cause pain and require pain medication, antibiotics, and surgical removal.
Dental pain (toothache)

The most common cause of a toothache is a dental cavity. The second most common is gum disease. Toothache can be caused by a problem that does not originate from a tooth or the jaw
Dentin

Dentin is the hard tissue of the tooth surrounding the central core of nerves and blood vessels (pulp).
Denture

An artificial set of teeth that can be removed
Denver Developmental Screening Test

The Denver Developmental Screening Test (DDST) is a widely used assessment for examining children 0-6 years of age as to their developmental progress. The name 'Denver' reflects the fact that this screening test was…
Deoxyhemoglobin

The form of hemoglobin without oxygen, the predominant protein in red blood cells. Hemoglobin forms an unstable, reversible bond with oxygen. In its oxygen-loaded form it is oxyhemoglobin and is bright red. In the…
Deoxyribonucleic acid

DNA. One of two types of molecules that encode genetic information. (The other is RNA. In humans DNA is the genetic material; RNA is transcribed from it. In some other organisms, RNA is the genetic material and, in…
Department of Energy (DOE).

One of the U.S. government agencies contributing to the Human Genome Project
Department of Health and Human Services

The United States government's principal agency for 'protecting the health of all Americans and providing essential human services, especially for those who are least able to help themselves.' Also known as DHHS and…
Depigmentation

Loss of color (pigment) from the skin, mucous membranes, hair, or retina of the eye. The color of the skin, mucous membranes, hair, and retina is due to the deposition of melanin, which is a coloring matter. Melanin is…
Depo-Provera contraceptive

Injectable progestin (Depo-Provera) was approved by the U.S. Food and Drug Administration (FDA) for contraception in 1992. It is injected by a health professional into the woman's buttocks or arm muscle every three…
Depression

Depression: An illness that involves the body, mood, and thoughts, that affects the way a person eats and sleeps, the way one feels about oneself, and the way one thinks about things. A depressive disorder is not the…
Depression, agitated

See: Agitated depression
Depression, bipolar

See: Bipolar disorder
Depression, dysthymia

A type of depression involving long-term, chronic symptoms that are not disabling, but keep a person from functioning at 'full steam' or from feeling good. Dysthymia is a less severe type of depression than what is…
Depression, major

Depression, major: A disease that interferes with the ability to work, sleep, eat, and enjoy once pleasurable activities. The signs and symptoms of major depression include loss of interest in activities that were once…
Depression, winter

Depression, winter: See: SAD
Dercum disease

A condition characterized by painful fatty tumors (lipomas) beneath the skin. The diseases tends to be associated with obesity and is about 5 times more frequent in females than in males. Onset of symptoms is generally…
Dermabrasion

Dermabrasion: Dermabrasion is a surgical procedure that involves the controlled abrasion (wearing away) of the upper layers of the skin with sandpaper or other mechanical means. The purpose of dermabrasion is to…
Dermal

Pertaining to the skin. From the Greek word derma for skin
Dermal

Suffix indicating a relationship to the skin. As in ectodermal, endodermal, and mesodermal; epidermal; and an intradermal injection. From the Greek word derma for skin
Dermatan sulfate

An glycosaminoglycan (formerly called a mucopolysaccharide) found mostly in skin but also in blood vessels, the heart valves, tendons, and the lungs. Dermatan sulfate accumulates abnormally in several of the…
Dermatitis

Inflammation of the skin, either due to direct contact with an irritating substance, or to an allergic reaction. Symptoms of dermatitis include redness, itching, and in some cases blistering. There are two types of…
Dermatitis and diarrhea, zinc deficiency

Diarrhea, zinc deficiency:Among the consequences of zinc deficiency, dermatitis (skin inflammation) and diarrhea are particularly prominent features. A genetic disease called acrodermatitis enteropathica in which there…
Dermatitis, atopic

A skin disease characterized by areas of severe itching, redness, scaling, and loss of the surface of the skin (excoriation). When the eruption (rash) has been present for a prolonged time, chronic changes occur due to…
Dermatitis, stasis

A skin irritation on the lower legs, generally related to circulatory problems. Stasis refers to a stoppage or slowdown in the flow of blood (or other body fluid such as lymph). A stasis ulcer is an ulcer (a crater)…
Dermatofibroma

A common type of benign skin tumor that is small, slow-growing, typically firm, red-to-brown and most often on the legs. Also called a fibrous histiocytoma. They can grow up to about 1 cm (less than a half inch) in…
Dermatofibrosarcoma protuberans

The heart is reversed and is in the right side of the chest rather than in its normal location on the left. This is a true anatomic reversal. With dextrocardia, for example, the apex (tip) of the heart points to the…
Dermatoglyphic

Pertaining to dermatoglyphics -- the study of dermal ridges on the fingers, palms, toes, and soles