PANTOTHENIC ACID
PARANOIA
pantothenic acid One of the vitamins
in the
vitamin B complex.
papain A naturally occurring mixture of
enzymes,
including chymopapain, which
is found in pawpaws. Papain breaks
down proteins and has been used to
remove clotted blood and dead tissue
from wounds and ulcers.
papilla Any small, nipple-shaped pro-
jection from a tissue's surface, such as
the mammary papilla (the breast nipple).
papilloedema Swelling of the head of
the
optic nerve,
which is visible with an
ophthalmoscope.
Also called optic disc
oedema, it usually indicates a danger-
ous rise in the pressure within the skull,
sometimes caused by a
brain tumour.
papilloma A noncancerous growth of the
epithelium
that resembles a wart and
most commonly affects the skin, tongue,
larynx, and urinary and digestive tracts.
pap smear See
cervical smear test.
papule A small, solid, slightly raised
area of skin. Papules are usually less
than 5 mm in diameter, are raised or
flat, have a smooth or warty texture,
and are either pigmented or the colour
of the surrounding skin.
par-/para- Prefixes that may mean be-
side or beyond, closely resembling or
related to, or faulty or abnormal.
para-aminobenzoic
acid The active
ingredient of many
sunscreen
prepara-
tions. Its abbreviation is PABA.
paracentesis A procedure in which a
body cavity is punctured with a needle
from the outside to remove fluid for
analysis, to relieve pressure from excess
fluid, or to instil drugs.
paracetamol An
analgesic drug,
used
to treat mild pain and to reduce fever.
Paracetamol may rarely cause nausea or
rash. An overdose may cause
liver dam-
age
and can be fatal.
paraesthesia Altered sensation in the
skin that occurs without a stimulus (see
pins-and-needles
).
paraffinoma A
tumour-like
swelling
under the skin caused by prolonged
exposure to paraffin. Paraffinomas may
form in the lungs if paraffin is inhaled.
paraldehyde A
sedative drug
used to
stop prolonged epileptic
seizures
. Par-
aldehyde can be administered as an
enema
or by injection into a muscle.
paralysis Complete or partial loss of
controlled movement caused by the in-
ability to contract
1
or more
muscles.
Paralysis may be temporary or perma-
nent. There may also be loss of feeling
in affected areas.
Paralysis of one half of the body is
called
hemiplegia;
paralysis of all 4 limbs
and the trunk is called
quadriplegia. Para-
plegia
is paralysis of both legs and
sometimes part of the trunk. Paralysis
may be flaccid, causing floppiness, or
spastic, causing rigidity.
Paralysis can be caused by brain disor-
ders such as
stroke, brain tumour, brain
abscess
, or
brain haemorrhage
. Some
types of paralysis are caused by damage
to parts of the nervous system (such as
the
cerebellum
and
basal ganglia
) con-
cerned with fine control of movement.
Paralysis can also be caused by damage
to or pressure on the spinal cord as a
result of injury or
disc prolapse
. Disea-
ses affecting the spinal cord (such as
multiple sclerosis
and
poliomyelitis
) and
muscle disorders (such as
muscular dys-
trophy
) may also cause paralysis. Nerve
disorders, called
neuropathies
, may cause
varying degrees of paralysis.
The underlying cause is treated, if
possible, and
physiotherapy
is used to
prevent joints from becoming locked
and to strengthen muscles and joints.
paralysis, periodic A rare, inherited
condition that affects young people.
Periodic paralysis is characterized by
episodes of muscle weakness, which
vary in frequency from daily to every few
years and last from a few minutes to a
few hours. In some cases, there is a drop
in the
potassium
levels in the blood; in
others, the levels rise. A carbohydrate-
rich meal may trigger an attack. The
condition often clears up without treat-
ment by age 40.
paramedic A term for any health-care
worker other than a doctor, nurse, or
dentist. The term usually refers to ambu-
lance staff who attend accidents or
medical emergencies.
paranoia A condition in which the cen-
tral feature is the
delusion
that people
or events are especially connected to
oneself. The term paranoia may also be
used to describe feelings of persecution.
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