%0 Journal Article %T Transsulfuration Is a Significant Source of Sulfur for Glutathione Production in Human Mammary Epithelial Cells %A Andrea D. Belalc¨¢zar %A John G. Ball %A Leslie M. Frost %A Monica A. Valentovic %J ISRN Biochemistry %D 2013 %I Hindawi Publishing Corporation %R 10.1155/2013/637897 %U http://dx.doi.org/10.1155/2013/637897