Sentence:  In our work the best procedure for removing substances causing nonspecific staining in order to obtain specific conjugates was to pass the conjugates through a DEAE-cellulose <WSD>column</WSD> and in some cases to absorb the first and second milliliter fractions with sweet clover tissue powder . 
Meaning of the word marked with <WSD> tags:  a vertical glass tube used in column chromatography; a mixture is poured in the top and washed through a stationary substance where components of the mixture are adsorbed selectively to form colored bands