|
|
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
Pope Sylvester II tried to introduce Arabic numbers into Europe between the years 999 and 1003, but their use did not catch on for a few more centuries, and Roman numerals continued to be the primary number system.
According to the Migraine Research Foundation, migraines are the third most prevalent illness in the world. Women are most affected (18%), followed by children of both sexes (10%), and men (6%).
The types of cancer that alpha interferons are used to treat include hairy cell leukemia, melanoma, follicular non-Hodgkin's lymphoma, and AIDS-related Kaposi's sarcoma.