Certain reducible compounds are useful in analytical compositions, elements and methods, e.g. for {HEAD ~ assays} of {TAIL ~ bacterial cells} 
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Certain reducible compounds are useful in analytical compositions , elements and methods , e.g. for { HEAD ~ assays } of { TAIL ~ bacterial cells }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL