Scientists at the Goddard Space Flight Center in Greenbelt,Maryland, found the substance glycine in material brought back to Earth from a comet.
VOA: special.2009.09.30
He made everything - except coffee - from sourdough, a substance used in making sourdough bread.
VOA: special.2009.01.24
Cells in the airways begin to produce too much of a thick, sticky substance called mucous.
VOA: special.2009.07.28
Later,Mizz Blackburn and Mizz Greider discovered the substance in the body that builds telomeres.
VOA: special.2009.10.07
Ultraviolet light from the sun changes a substance in the skin into vitamin D.
VOA: special.2009.04.21
Later,it became the active substance in a medicine that Bayer called aspirin.
VOA: special.2009.10.20
It is also needed to make a light-sensitive substance in the eyes.
VOA: special.2009.04.21
He was studying a substance in the hull that covers rice.
VOA: special.2009.04.21
The competition includes acetaminophen, the active substance in products like Tylenol.
VOA: special.2010.12.14
The substance is used in toothpaste and medicine for stomach problems.
VOA: special.2009.08.25
Scientific eExpert in WHO's Mental Health and Substance Abuse Department, Alexandra Fleischmann says risk factors vary in different cultures.
VOA: standard.2009.09.10
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