单词：orcin
obtained from certain lichens (Roccella, Lecanora, etc.), also from
extract of aloes, and artificially from certain derivatives of toluene.
It changes readily into orcein.
单词：orcin 相关文章
Millions More Children to Receive Vaccines More than one million children die each year from severe diarrhea and pneumococcal disease. Today (Tuesday), the GAVI Alliance announced an expanded campaign against the two leading killers of children world
VOA标准英语2011年(九月)
Sorry,there is not text temporarily, Please help tingroom to look for it! 如果您能找到更好的听力原文，请发贴到 听力原文收集区 ，您将会获得10到30积分的奖励! Thank you！
单词解析速记
US Scientists Expand Scope of HIV Vaccine Study The worlds largest ongoing HIV vaccine study has been expanded to consider multiple ways a vaccine might boost immune response to the AIDS virus. The U.S. Institute of Allergy and Infectious Diseases (N
VOA标准英语2011年(八月)
Broadcast on Coast to Coast: November 7, 2002 Rebroadcast on VOA News Now: November 10, 2002 AA: I'm Avi Arditti with Rosanne Skirble, and this week on WORDMASTER -- slang and idioms in American politics. RS: Tuesday was Election Day, and Slangman Da
词汇大师(Wordmaster)
By Jessica Berman Washington 11 May 2006 French researchers at the Sanofi Pasteur Institute say they have developed a bird flu vaccine that, so far, appears to be safe and effective in humans. But obs
2006年VOA标准英语（五月）