| Xanthelasma |
fatty
deposits around the eyes that are common in elderly people
and are associated with high levels of cholesterol in the
blood |
| Xanthine |
a
bronchodilator drug that is used to treat asthma |
| Xanthomatosis |
a
condition in which fatty deposits occur in various parts of
the body, possibly leading to atherosclerosis |
| X
chromosome |
one
of the two sex chromosomes; determines female sex characteristics
|
| Xeroderma
pigmentosum |
a
genetic disorder in which the skin is extremely sensitive
to sunlight, causing it to age prematurely and leaving the
individual particularly susceptible to skin cancer |
| Xerophthalmia |
excessive
dryness of the cornea and conjunctiva due to a lack of vitamin
A |
| X-linked
disorder |
a
genetic disorder in which the abnormal gene is located on
the X chromosome; those affected are almost always men |
| X-ray |
see
Radiography |
| XYY
syndrome |
a
disorder in which a man has an extra Y chromosome, causing
him to be unusually tall and to have behavioral disorders |
