2367
We conducted a search of MEDLINE from January 1980 to July 2011 using PubMed , Cochrane Database of Systematic Reviews and Controlled Trials , CINAHL , and EMBASE .
 None
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 None