|
|
The horizontal fraction bar was introduced by the Arabs.
A strange skin disease referred to as Morgellons has occurred in the southern United States and in California. Symptoms include slowly healing sores, joint pain, persistent fatigue, and a sensation of things crawling through the skin. Another symptom is strange-looking, threadlike extrusions coming out of the skin.
Autoimmune diseases occur when the immune system destroys its own healthy tissues. When this occurs, white blood cells cannot distinguish between pathogens and normal cells.
All adults should have their cholesterol levels checked once every 5 years. During 2009–2010, 69.4% of Americans age 20 and older reported having their cholesterol checked within the last five years.
The average older adult in the United States takes five prescription drugs per day. Half of these drugs contain a sedative. Alcohol should therefore be avoided by most senior citizens because of the dangerous interactions between alcohol and sedatives.