|
|
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.
Malaria was not eliminated in the United States until 1951. The term eliminated means that no new cases arise in a country for 3 years.
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.
There can actually be a 25-hour time difference between certain locations in the world. The International Date Line passes between the islands of Samoa and American Samoa. It is not a straight line, but "zig-zags" around various island chains. Therefore, Samoa and nearby islands have one date, while American Samoa and nearby islands are one day behind. Daylight saving time is used in some islands, but not in others—further shifting the hours out of sync with natural time.
The familiar sounds of your heart are made by the heart's valves as they open and close.
![Much of the dark space between stars, as seen in the sky of the image above, is due to the human eye](https://biology-forums.com/gallery/47/medium_27605_22_04_12_6_16_47.jpeg)
![The meninges from the outside in: dura mater, arachnoid, and pia mater. Also showing the subarachnoi](https://biology-forums.com/gallery/47/medium_14755_07_10_12_3_19_31_93231166.jpeg)