|
|
Most strokes are caused when blood clots move to a blood vessel in the brain and block blood flow to that area. Thrombolytic therapy can be used to dissolve the clot quickly. If given within 3 hours of the first stroke symptoms, this therapy can help limit stroke damage and disability.
The horizontal fraction bar was introduced by the Arabs.
The tallest man ever known was Robert Wadlow, an American, who reached the height of 8 feet 11 inches. He died at age 26 years from an infection caused by the immense weight of his body (491 pounds) and the stress on his leg bones and muscles.
When Gabriel Fahrenheit invented the first mercury thermometer, he called "zero degrees" the lowest temperature he was able to attain with a mixture of ice and salt. For the upper point of his scale, he used 96°, which he measured as normal human body temperature (we know it to be 98.6° today because of more accurate thermometers).
Ether was used widely for surgeries but became less popular because of its flammability and its tendency to cause vomiting. In England, it was quickly replaced by chloroform, but this agent caused many deaths and lost popularity.
![The approval of a new drug is a four-stage process: (1) preclinical investigation, (2) clinical inve](https://biology-forums.com/gallery/47/medium_246815_06_04_15_9_49_12_21219513.jpeg)
![The Land Ordinance of 1785 called for surveying and dividing the Western Territories into square mil](https://biology-forums.com/gallery/47/medium_374628_16_08_15_9_46_10_22249558.jpeg)