Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «S»:
Study, gastric emptying
Study, gastric emptying: A gastric emptying study evaluates the emptying of food from the stomach.
For a gastric emptying study, a patient eats a meal in which the solid food, liquid food or both are mixed with a small amount of radioactive material. A scanner (acting like a Geiger counter) is pl...
Study, linkage: A study aimed at establishing linkage between genes. Linkage is the tendency for genes and other genetic markers to be inherited together because of their location near one another on the same chromosome.
A gene is a functional physical unit of heredity that can be passed from paren...
Study, longitudinal: A study done over the passage of time. For
example, a longitudinal study of children with Down syndrome (trisomy 21) might involve
the study of 100 children with this condition from birth to 10 years of age. Also called a
diachronic study. The opposite of a cross-sectional (sync...
Study, preclinical: A study to test a drug, procedure or medical
treatment in animals. The aim is to collect data in support of safety. Preclinical studies
are required before clinical trials can be started....
Study, stomach emptying
Study, stomach emptying: Also called a gastric emptying study, this test evaluates the emptying of food from the stomach.
For a gastric emptying study, a patient eats a meal in which the solid food, liquid food or both are mixed with a small amount of radioactive material. A scanner (acting like ...
Study, synchronic: See: Study, cross-sectional. ...
Stuffy nose: The presence of increased secretions and mucus in the nasal
passages, most commonly arising as a result of a common cold, allergic reaction, or inflammation or infection of the paranasal sinuses (sinus infection)....
Sturge-Weber syndrome: A congenital, but
not inherited, disorder that affects the skin, the
neurological system, and sometimes the eyes and internal
organs. The main sign of Sturge-Weber syndrome is a port
wine stain birthmark. Neurological symptoms may include
seizures and developmental delay...
Stye: A stye is a red tender bump on the eyelid that is caused
by an acute infection of the oil glands of the eyelid. A stye can also be a
complication of blepharitis.
Other spellings, sty...
Sub-: Prefix meaning meaning under, below, less than normal, secondary, less than fully. As in subacute, subaortic stenosis, subarachnoid, subclavian, subclinical disease, subcutaneous, subdural, subglottis, subjacent, sublingual, subluxation, and subtotal hysterectomy.
From the Latin preposition...
Rather recent onset or somewhat rapid change. The term "subacute" is used in contrast to acute which indicates very sudden onset or rapid change and chronic which indicates indefinite duration or virtually no change. A chronic condition is one lasting 3 months or more, by the definition of...
Subacute sclerosing panencephalitis (SSPE)
Subacute sclerosing panencephalitis
(SSPE): A chronic brain disease of children and
adolescents that occurs months to often years after an
attack of measles, causing convulsions, motor
abnormalities, mental retardation and, usually, death.
Subacute spongiform encephalopathy
Subacute spongiform encephalopathy: See: Gerstmann-Straussler-Scheinker syndrome....
Subaortic stenosis: Narrowing
of the left ventricle of the heart just below the aortic valve through
which blood must pass on its way up into the
aorta. The narrowing
cuts the flow of blood. Subaortic stenosis may be congenital (present at birth)
as part of a particular form of...
Subarachnoid: Literally, beneath the arachnoid, the middle of three membranes that cover the central nervous system. In practice, subarachnoid usually refers to the space between the arachnoid and the pia mater, the innermost membrane surrounding the central nervous system.
The subarachnoid space i...