|
|
Fewer than 10% of babies are born on their exact due dates, 50% are born within 1 week of the due date, and 90% are born within 2 weeks of the date.
During the twentieth century, a variant of the metric system was used in Russia and France in which the base unit of mass was the tonne. Instead of kilograms, this system used millitonnes (mt).
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
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.
More than nineteen million Americans carry the factor V gene that causes blood clots, pulmonary embolism, and heart disease.