9858
In this study , the EC ( 50 ) estimation was performed using a comparative approach based on various regression models implemented in six specialized computer programs : GraphPad Prism (R) version 5 . 01 , BLeSq , OriginPro (R) 8 . 5 . 1 , SigmaPlot (R) 12 , BioDataFit (R) 1 . 02 , and IBM SPSS Statistics (R) Desktop 19 . 0 .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
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