|
|
Asthma is the most common chronic childhood disease in the world. Most children who develop asthma have symptoms before they are 5 years old.
Elderly adults are at greatest risk of stroke and myocardial infarction and have the most to gain from prophylaxis. Patients ages 60 to 80 years with blood pressures above 160/90 mm Hg should benefit from antihypertensive treatment.
Only one in 10 cancer deaths is caused by the primary tumor. The vast majority of cancer mortality is caused by cells breaking away from the main tumor and metastasizing to other parts of the body, such as the brain, bones, or liver.
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.
In 1835 it was discovered that a disease of silkworms known as muscardine could be transferred from one silkworm to another, and was caused by a fungus.