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In 1864, the first barbiturate (barbituric acid) was synthesized.
Signs of depression include feeling sad most of the time for 2 weeks or longer; loss of interest in things normally enjoyed; lack of energy; sleep and appetite disturbances; weight changes; feelings of hopelessness, helplessness, or worthlessness; an inability to make decisions; and thoughts of death and suicide.
Serum cholesterol testing in adults is recommended every 1 to 5 years. People with diabetes and a family history of high cholesterol should be tested even more frequently.
There are 20 feet of blood vessels in each square inch of human skin.
The senior population grows every year. Seniors older than 65 years of age now comprise more than 13% of the total population. However, women outlive men. In the 85-and-over age group, there are only 45 men to every 100 women.
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