|
|
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.
Interferon was scarce and expensive until 1980, when the interferon gene was inserted into bacteria using recombinant DNA technology, allowing for mass cultivation and purification from bacterial cultures.
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 heart is located in the center of the chest, with part of it tipped slightly so that it taps against the left side of the chest.
Common abbreviations that cause medication errors include U (unit), mg (milligram), QD (every day), SC (subcutaneous), TIW (three times per week), D/C (discharge or discontinue), HS (at bedtime or "hours of sleep"), cc (cubic centimeters), and AU (each ear).
![A typical variable cam timing control valve. The solenoid is controlled by the engine computer and ...](https://biology-forums.com/gallery/29/medium_548020_30_05_17_3_43_29_29648118.png)
![Typical ignition timing map developed from testing and used by the vehicle computer to provide the ...](https://biology-forums.com/gallery/29/medium_548020_30_05_17_8_05_57_29883514.png)