|
|
As the western states of America were settled, pioneers often had to drink rancid water from ponds and other sources. This often resulted in chronic diarrhea, causing many cases of dehydration and death that could have been avoided if clean water had been available.
The modern decimal position system was the invention of the Hindus (around 800 AD), involving the placing of numerals to indicate their value (units, tens, hundreds, and so on).
Adolescents often feel clumsy during puberty because during this time of development, their hands and feet grow faster than their arms and legs do. The body is therefore out of proportion. One out of five adolescents actually experiences growing pains during this period.
Parkinson's disease is both chronic and progressive. This means that it persists over a long period of time and that its symptoms grow worse over time.
Every 10 seconds, a person in the United States goes to the emergency room complaining of head pain. About 1.2 million visits are for acute migraine attacks.