Webster's New World Medical Dictionary

Listeria
A group of bacteria that can infect both
animals and humans. See also 
Listeriosis.
Listeriosis
A disease that is caused by eating
food contaminated with the bacterium Listeria
monocytogenes. Listeriosis is an important public
health problem in North America. The disease
affects primarily pregnant women, newborns, and
anyone who is immunocompromised. Symptoms
include fever, muscle aches, nausea, and diarrhea.
If infection spreads to the nervous system, symp-
toms such as headache, stiff neck, confusion, loss of
balance, or convulsions can occur. Infection during
pregnancy may appear mild but can lead to still-
birth, premature delivery, and infection of the new-
born. Persons who are at risk of contracting
Listeriosis can prevent the infection by avoiding cer-
tain high-risk foods and by handling food properly.
Raw food from animal sources (such as beef, pork,
or poultry) should be thoroughly cooked and
uncooked meats should be kept separate from veg-
etables, cooked foods, and ready-to-eat foods. Raw
vegetables should be washed thoroughly before
being eaten, and raw (unpasteurized) milk or foods
made from raw milk should be avoided.
liter
A metric measure of capacity that is equal to
the volume of 1 kilogram of water at 4° Celsius and
at standard atmospheric pressure of 760 millime-
ters of mercury. There are 1,000 cubic centimeters,
or 1 cubic decimeter, in 1 liter. A liter is a little more
than 1 quart (1.057 US liquid quarts). Abbreviated
L or l.
lithium
A naturally occurring salt that, in purified
form, is used to treat certain psychiatric disorders,
especially bipolar disease The therapeutic level of
lithium—the amount needed to treat bipolar disor-
ders—is perilously close to the level that can cause
toxicity, so monitoring of blood levels is required.
Symptoms of lithium toxicity include diarrhea, vom-
iting, blurred vision, loss of coordination, and loss
of motor control. Treatment of lithium toxicity
involves immediately reducing or discontinuing
lithium use under medical supervision.