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Images from spacecraft show areas with winding valleys that apparently were eroded by runningwater.
The first oncogene was discovered in 1970 and was termed SRC (pronounced "SARK").
Bacteria have been found alive in a lake buried one half mile under ice in Antarctica.
Blood in the urine can be a sign of a kidney stone, glomerulonephritis, or other kidney problems.
On average, the stomach produces 2 L of hydrochloric acid per day.
Human stomach acid is strong enough to dissolve small pieces of metal such as razor blades or staples.
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