PARAPARESIS
PARATHYROID GLANDS
P
A paranoid person builds up an elabo-
rate
set
of
beliefs
based
on
the
interpretation of chance remarks or
events. Typical themes are persecution,
jealousy (see
jealousy, morbid),
love,
and grandeur.
Paranoia may be
chronic
or
acute.
Chronic paranoia may be caused by
brain damage, abuse of alcohol or am-
fetamines,
manic-depressive illness,
or
schizophrenia
and is likely in those with
a
personality disorder.
Acute paranoia,
lasting for less than
6
months, may
occur in people, such as refugees, who
have experienced radical changes. In
shared paranoia (see
folie a
deux), delu-
sion
develops
because
of
a
close
relationship with someone else who
has a delusion.
There are usually no other symptoms
of mental illness apart from occasional
hallucinations
. In time, anger, suspicion,
and social isolation may become severe.
If acute illness is treated early with
antipsychotic drugs,
the outlook is good.
In longstanding paranoia, delusions are
usually firmly entrenched, but antipsy-
chotics may make them less prominent.
paraparesis Partial
pardysis
or weak-
ness of both legs and sometimes part of
the trunk.
paraphimosis Constriction of the
penis
behind the
glans
(head) by an extremely
tight foreskin that has been pulled back,
causing swelling and pain. Paraphim-
osis often occurs as a complication of
an abnormally tight foreskin (see
phimo-
sis
). The foreskin can often be returned
manually to its normal position after
application of an ice-pack. Otherwise,
an injection or an operation to cut the
foreskin may be necessary.
Circumcision
prevents recurrence.
paraplegia Weakness or
paralysis
of
both legs and sometimes of part of the
trunk, often accompanied by loss of
feeling and by loss of urinary control.
Paraplegia is a result of nerve damage
in the
brain
or
spinal cord
.
parapsychology The branch of
psy-
chology
dealing with experiences and
events that cannot be scientifically
accounted for. These include forms of
extrasensory perception (ESP), such as
telepathy (communication of thoughts),
telekinesis (movement of objects with
the mind), and precognition (being able
to see into the future).
Many “paranormal” experiences can
probably be explained by mental distur-
bances; others are probably due to
coincidence, self-deception, or fraud.
paraquat A poisonous weedkiller that is
available in high concentrations for agri-
cultural use and which can be fatal if
swallowed, inhaled, or absorbed through
the skin. Paraquat poisoning requires
urgent medical attention. The symptoms
may include breathing difficulties, mouth
ulcers, nosebleeds, diarrhoea, and later,
respiratory and kidney failure. Treat-
ments include eating activated charcoal
or Fuller's earth.
Haemodidysis
may
also be used.
parasite Any organism living in or on
another living creature and deriving
advantage from it, while causing the
host disadvantage. The parasite obtains
food from the host's blood, tissues, or
diet. Parasites may spend only part of
their life-cycles with the host or remain
there permanently. Some parasites cause
few symptoms, while others cause dis-
ease or even death.
Animal parasites of humans include
protozoa, worms, flukes, leeches, lice,
ticks,
and
mites. Viruses
and disease-
causing
fungi
and
bacteria
are also
essentially parasites.
parasitology The scientific study of
parasites
. Although viruses and many
types of bacteria and fungi are para-
sites, their study is conducted under the
title of
microbiology
.
parasuicide See
suicide, attempted.
parasympathetic
nervous
system
One of the 2 divisions of the
autonomic
nervous system
.
parathion A highly poisonous agricul-
tural
organophosphate
insecticide.
parathyroid glands Two pairs of oval,
pea-sized glands that lie behind the
thyroid gland
in the neck. Some people
have only
1
parathyroid gland or have
extra glands in the neck or chest. The
glands produce parathyroid
hormone
,
which helps regulate the level of calci-
um in the blood; even small variations
in calcium level can impair muscle and
nerve function. Rarely, the parathyroid
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