Medical terms - Letter S (page 13) | MedicalVocabulary.org

Slapped cheek

See: Fifth disease
SLE (systemic lupus erythematosus)

A chronic inflammatory condition caused by an autoimmune disease. An autoimmune disease occurs when the body's tissues are attacked by its own immune system. Patients with lupus have unusual antibodies in their blood…
Sleep

Sleep: The body's rest cycle. Sleep is triggered by a complex group of hormones that are active in the main, and that respond to cues from the body itself and the environment. About 80 percent of sleep is dreamless, and…
Sleep apnea

Sleep apnea: The temporary stoppage of breathing during sleep, often resulting in daytime sleepiness. Apnea is a Greek word that means 'want of breath.' The most common form of sleep apnea is obstructive sleep apnea. In…
Sleep apnea, central

A breathing disorder characterized by brief interruptions of breathing during sleep. Central sleep apnea occurs when the brain fails to send the appropriate signals to the breathing muscles to initiate respirations…
Sleep apnea, obstructive

Sleep apnea is a breathing disorder characterized by brief interruptions of breathing during sleep. It owes its name to a Greek word, apnea, meaning 'want of breath.' There are two types of sleep apnea: central and…
Sleep disorders

Sleep disorders: Any disorder that affects, disrupts, or involves sleep. The most common sleep disorder is probably snoring, although it is usually not medically significant. Insomnia, sleep apnea, restless leg…
Sleep drug

Any drug used to help sleep. Most prescription sleep drugs are sedative hypnotic agents. They include Valium, Xanax, Restoril, Ambien, and Sonata
Sleep jerk

See: Hypnic jerk
Sleep paralysis

A frightening form of paralysis that occurs when a person suddenly finds himself or herself unable to move for a few minutes, most often upon falling asleep or waking up. Sleep paralysis is due to an ill-timed…
Sleep restriction therapy

A type of therapy in which the number of hours of sleep are restricted. Sleep restriction therapy is used in insomnia. Some people with insomnia spend too much time in bed unsuccessfully trying to sleep. They may…
Sleep start

See: Hypnic jerk
Sleep talking

NREM (non-rapid eye movement) sleep is dreamless sleep. During NREM, the brain waves on the electroencephalographic (EEG) recording are typically slow and of high voltage, the breathing and heart rate are slow and…
Sleep, non-rapid eye movement

Sleep, non-rapid eye movement: NREM (non-rapid eye movement) sleep is dreamless sleep. During NREM, the brain waves on the electroencephalographic (EEG) recording are typically slow and of high voltage, the breathing…
Sleep, NREM

Sleep, NREM: NREM (non-rapid eye movement) sleep is dreamless sleep. During NREM, the brain waves on the electroencephalographic (EEG) recording are typically slow and of high voltage, the breathing and heart rate are…
Sleep, paroxysmal

Sleep, paroxysmal: A neurological disorder marked by a sudden recurrent uncontrollable compulsion to sleep. Also known as narcolepsy. The disorder is often associated with cataplexy (a sudden loss of muscle tone and…
Sleep, rapid eye movement

Sleep, rapid eye movement: REM sleep is the portion of sleep when there are rapid eye movements (REMs). Dreams occur during REM sleep. We typically have 3 to 5 periods of REM sleep per night. They occur at intervals of…
Sleep, REM

Sleep, REM: REM sleep is the portion of sleep when there are rapid eye movements (REMs). Dreams occur during REM sleep. We typically have 3 to 5 periods of REM sleep per night. They occur at intervals of 1-2 hours and…
Sleep, twilight

Sleep, twilight: A term applied to the combination of analgesia (pain relief) and amnesia (loss of memory) produced by a mixture of morphine and scopolamine ('scope') given by a hypodermic injection (an injection under…
Sleep-disordered breathing

A condition characterized by repeated episodes of hypopnea (underbreathing) and apnea (not breathing) during sleep. A significant proportion of adults are thought to experience sleep-disordered breathing…
Sleepiness, excessive daytime (EDS)

A neurological disorder marked by a sudden recurrent uncontrollable compulsion to sleep. Also known as narcolepsy. It is often associated with cataplexy (a sudden loss of muscle tone and paralysis of voluntary muscles…
Sleeping disease

A neurological disorder marked by a sudden recurrent uncontrollable compulsion to sleep. Also known as narcolepsy. The disorder is often associated with cataplexy (a sudden loss of muscle tone and paralysis of voluntary…
Sleeping sickness, African

See: African sleeping sickness
Sleeplessness

Insomnia. See also Fatal familial insomnia
Sleepwalking

Sleepwalking: Purposeful moving, usually but not always including walking, while in a deep stage of sleep. Sleepwalking occurs most frequently in children, particularly boys. Sedatives tend to exacerbate rather than…
Sliding hiatal hernia

Hiatal hernias are categorized as being either sliding or para-esophageal. Sliding hiatal hernias are those in which the junction of the esophagus and stomach, referred to as the gastro- esophageal junction, and part of…
Slipped disc

Rupturing of the tissue that separates the vertebral bones of the spinal column. The center of the disc, which is called the nucleus, is soft, springy and receives the shock of standing, walking, running, etc. The outer…
Slipped elbow

See: Nursemaid's elbow
Slipped spine

See: Spondylolisthesis
Slipped vertebra

See: Spondylolisthesis
Slow virus

1. A virus that has a long incubation period before the onset of a gradually progressive disease. 2. Specifically, one of the Lentivirinae, a subfamily of viruses that are nononcogenic retroviruses such as Visna virus…
Slow-wave sleep

Sleep: Stage 3 and 4 non-rapid eye movement (non-REM) sleep. Slow-wave sleep is characterized by brain wave patterns (electroencephalogram or EEG) with a frequency of less than 4 Hz and peak-to-peak amplitude of 75…
SLS (Sjogren-Larsson syndrome)

The Sjogren-Larsson syndrome is a genetic (inherited) disease usually characterized by a triad of clinical findings consisting of ichthyosis (thickened fish-like skin), spastic paraplegia (spasticity of the legs) and…
Sludge, biliary

A mixture of microscopic particulate matter in bile that occurs when particles of material precipitate from bile. (Bile is the fluid that is made by the liver. It is stored in the gallbladder until after a meal when it…
SLV

Sapporo-like virus. See: Sapovirus
Sly syndrome

A disorder of mucopolysaccharide metabolism characterized by short stature, coarsening of the facial features, clouding of the cornea, striking enlargement of the liver and spleen, skeletal abnormalities, and…
SMA

Spinal muscular atrophy
Smad3

A protein in a pathway that helps prevent tumors. Smad3 is a player in a cellular network relay system called the transforming growth factor B (TGF-B) signaling cascade. TGF-B binds to receptors on the surface of blood…
SMAD4

See: MADH4
SMAD4/DPC4

See: MADH4
Small bowel

Another name for the small intestine. The word 'bowel' originated from the Latin 'botulus' meaning 'sausage.'
Small calorie

See: Calorie
Small calorie (Calorie)

A type of lung cancer in which the cells appear small and round under the microscope. Also called oat cell lung cancer.
Small cell lung cancer

A type of lung cancer in which the cells appear small and round under the microscope. Also called oat cell lung cancer
Small eye

Also called microphthalmia, an abnormally small eye, a congenital malformation (birth defect) of the globe. The related term 'anophthalmia' means no eye and refers to absence of the globe and ocular tissue from the…
Small for gestational age (SGA)

SGA infants weigh 2500 g or less at birth and are considered to have intrauterine growth retardation (IUGR), given their gestational age. By contrast, an infant may weighs 2500 g or less simply because of prematurity.
Small inducible cytokine A2

See: MPC1
Small inhibitory RNA

See: siRNA
Small intestine

The part of the digestive tract that extends from the stomach to the large intestine
Small intestine insufficiency

See: Short bowel syndrome