stenosis Narrowing of a duct, canal,
passage, or tubular organ.
stent A rigid tube that is surgically inser-
ted to open up or keep open any body
canal that may have become narrowed or
closed up due to disease. Stents are used
to open narrowed coronary arteries in
heart disease. They are also used to
relieve blockages caused by a tumour, for
example in the
sterculia A bulk-forming
treat constipation. It is especially useful
when stools are small and hard. Stercu-
lia should only be used if fibre intake
cannot be increased; adequate fluid
intake must be maintained to avoid in-
testinal obstruction. Side effects may
include flatulence, bloating, and gastro-
intestinal obstruction or impaction.
stereotaxic surgery Brain operations
carried out by inserting delicate instru-
ments through a surgically created hole
in the skull and guiding them, with the
, to a specific area.
Stereotaxic procedures can be used to
; for a brain
or to destroy small areas of the brain to
treat disabling neurological disorders.
sterility The state either of being germ-
free or of permanent
sterilization The complete destruction
or removal of living organisms, usually to
prevent spread of infection; any proce-
dure that renders a person infertile (see
sterilization, female; vasectomy).
sterilization, female A usually perma-
nent method of
the fallopian tubes are sealed in order
to prevent sperm reaching the ova.
small incisions in the abdomen. Some-
times it is done by minilaparotomy, in
which a single incision is made in the
pubic area. The fallopian tubes are
sealed using clips or by cutting and
tying. The operations have a low failure
rate. Fertility can sometimes be restored
after sterilization using
sterilization, male See
sternum The long, narrow, flat plate of
bone at the front of the chest. The ster-
num has 3 parts: an upper, triangular
portion (manubrium); a long middle part
(body); and, at the lower end, a small,
leaf-shaped projection (xiphoid process).
The upper manubrium articulates with
the inner ends of the
are attached to the sides of the manubri-
um and body by cartilage. Between the
manubrium and body is a
joint, allowing slight movement when
the ribs rise and fall during breathing.
Great force is required to fracture the
sternum. The main danger of such an
injury is the possibility that the broken
bone may be driven inwards, damaging
the heart, which lies behind the sternum.
steroid drugs A group of drugs includ-
steroids, anabolic Drugs that have an
anabolic (protein-building) effect similar
. Anabolic steroids build
tissue, promote muscle recovery after
an injury, and strengthen bones. They
are used to treat
steroids are often
abused by athletes.
effects of the drugs
, damage to the
liver and adrenal
impotence in men,
instrument that is
used for listening
SITES OF INCISION
LAPAROSCOPIC CLIP STERILIZATION