BOIL
blood transfusion, autologous
The use of a person’s own blood, which
had been donated at an earlier time, for
blood transfusion.Autologous
transfusion
eliminates the slight but serious risk of
contracting an infectious illness from
contaminated blood. Another advantage
is that there is no risk of a reaction
occurring as a result of incompatibility
between donor and recipient blood.
Up to 2.5 litres of a person’s blood
can be removed and stored in several
sessions up to three days before planned
surgery. There must be at least four days
between each session. Blood may also
be taken during surgery. The blood is fil-
tered and returned to the body.
blood transfusion, incompatible
A
blood transfusion
in which the recipi-
ent’s blood and the donor’s blood are
mismatched. As a result,
antibodies
that
are present in the recipient’s circulation
lead to destruction of the transfused
red
blood cells.
This can have serious conse-
quences, including
kidney failure
and
occasionally even death. Careful cross-
matching of blood in the laboratory
make incompatible transfusions rare.
blood vessels
A general term for arteries, veins, and
capillaries (see
circulatory system).
Bloom’s syndrome
A
genetic disorder
that is most commonly
found among people of East European
Jewish descent. Physical characteristics
of the syndrome include short stature, a
butterfly-shaped red rash on the face,
and
photosensitivity
(an abnormal reaction
to sunlight). Individuals with Bloom’s
syndrome may also be at increased risk
of certain cancers, such as
leukaemia
.
blue baby
An infant with a cyanotic (bluish) com-
plexion, especially visible on the lips
and tongue, caused by a relative lack of
oxygen in the blood. This is usually due
to a structural defect of the heart or the
major arteries leaving the heart. Such
defects may need to be corrected surgi-
cally (see
heart disease, congenital).
blue bloater
An outdated term to describe a person
with bluish lips and tongue and
oedema
(a buildup of fluid in the tissues). The
cause is long-term lung damage that has
led to heart failure (see
pulmonary dis-
ease, chronic obstructive).
blue naevus
A type of
naevus
(skin blemish) with a
dark blue or black coloration and a
clearly defined border. Blue naevi are
noncancerous and they are made up of
a collection of pigment-producing cells
called
melanocytes
.
blurred vision
Indistinct,
or
fuzzy,
visual
images.
Blurred vision, which should not be
confused with
double vision
(diplopia),
can occur in one eye or both, for epi-
sodes of varying lengths of time, and
can develop gradually or suddenly. The
usual cause of longstanding blurred
vision is a refractive error such as
astig-
matism
(unequal curvature of the front
of the eye),
hypermetropia
(longsighted-
ness), or
myopia
(shortsightedness), all
of which can be corrected by glasses or
contact lenses. After the age of 40,
pres-
byopia
(reduced ability to focus on near
objects) becomes more common.
Vision may also be blurred or im-
paired as a result of damage, disease, or
abnormalities of parts of the eye or its
connections to the brain. Blurred vision
as a result of disease is most commonly
caused by
cataract
or
retinopathy
.
blushing
Brief reddening of the face, and some-
times the neck, caused by widening of
the blood vessels close to the skin’s sur-
face. Blushing is often an involuntary
reaction to
embarrassment.
In some
women, blushing is a feature of the
hot
flushes
that occur during the
menopause
.
Flushing of the face also occurs in asso-
ciation with
carcinoid syndrome
.
B-lymphocyte
A type of
white blood cell,
also referred to
as a B-cell. B-lymphocytes play a vital
part in the
immune system,
the body’s
natural defence mechanism, by produc-
ing
antibodies
(special proteins) to find
and destroy harmful microorganisms.
BMI
The abbreviation for
body mass index.
BMR
The abbreviation for
basal metabolic rate.
BM-test 1-44
A brand-named
blood glucose monitoring
test strip for analysing the blood glu-
cose level in
diabetes mellitus.The
strip is
sensitive to blood glucose levels ranging
from 1 mmol to 44 mmol.
body contour surgery
Surgery that is performed to remove
excess fat, skin, or both, from various
parts of the body, especially from the
abdomen, the thighs, and the buttocks.
One of the most commonly used opera-
tions is abdominal wall reduction, also
called abdominoplasty, which involves
removing excess skin and fat from the
abdominal area.
To miminize scarring, a less invasive
procedure, such as suction lipectomy
(liposuction), may be performed. In
this operation, a rigid hollow tube is
inserted through a small incision in the
skin and is used to break up large areas
of fat. The fat can then be sucked out
through the instrument.
All body contour surgery carries a
risk of complications, including wound
infection. Minor irregularities and some
dimpling of the skin commonly occur
following liposuction.
body dysmorphic disorder
A psychiatric disorder in which a person
suffers intense anxiety about an imag-
ined defect in part of his or her body.
body image
A person’s perception of the different
parts of his or her own body.
body mass index (BMI)
An indicator of healthy body weight.
BMI is calculated by dividing weight
in kilograms by the square of height in
metres.The normal range is 20 to 25.
body odour
The smell caused by the action of
bac-
teria
on sweat. It is most noticeable in
the armpits and around the genital area,
where the
apocrine glands
contain pro-
teins and fatty materials favourable to
bacterial growth.
body temperature
See
temperature
.
boil
An inflamed, pus-filled area of skin,
usually an infected hair follicle. A more
severe and extensive form of boil invol-
ving several hair follicles is known as a
carbuncle.
The usual cause of a boil is
infection with the bacterium S
taphtio
-
coccus
aureus
. Recurrent boils may occur
in people with known or unrecognized
diabetes mellitus
or in those with other
conditions in which general resistance
to infection is impaired.
B
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