Scientists say an experimental vaccine reduced the risk of infection in human beings by thirty-one percent and was safe.
VOA: special.2009.10.13
Scientists say an experimental vaccine reduced the risk of infection in humans by thirty-one percent and was safe.
VOA: special.2009.09.30
"They were willing to risk their lives, in this case, to prevent Afghanistan from once again becoming a safe haven for al-Qaida and its extremist allies.
VOA: standard.2009.10.26
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