Webster's New World Medical Dictionary

parts. Most patients are children. Because impetigo
is caused by a bacterium that is transmitted onto the
skin, it is contagious and easily contracted by per-
sons who might touch the affected person.
Treatment involves the use of antibiotics.
implant, cochlear
See 
cochlear implant.
implantable cardiac defibrillator
See 
cardiac
defibrillator, implantable.
implantable pacemaker
See 
pacemaker,
internal.
impotence
See 
erectile dysfunction.
imprinting, psychological
A remarkable phe-
nomenon that occurs in animals, and theoretically
in humans, in the first hours of life. The newborn
creature bonds to the type of animals it meets at
birth and begins to pattern its behavior after them.
In humans, this is often called bonding, and it usu-
ally refers to the relationship between the newborn
and its parents.
in.
Abbreviation for inch.
in situ
In the normal location. An in situ tumor is
one that is confined to its site of origin and has not
invaded neighboring tissue or gone elsewhere in the
body. For example, squamous cell carcinoma in situ
is an early stage of skin cancer.
in situ, carcinoma
See 
carcinoma in situ.
in situ hybridization
The use of a DNA or RNA
probe to detect complementary genetic material in
cells or tissue. In situ hybridization involves
hybridizing a labeled nucleic acid to suitably pre-
pared cells or tissues on microscope slides to allow
visualization in situ (in the normal location).
in vitro
In glass, as in a test tube. An in vitro test
is one that is done in glass or plastic vessels in the
laboratory. In vitro is the opposite of in vivo.