For example, prolongation of the alkaline lysis step for {TAIL ~ 4 to 24 hours} together with the addition of lysozyme has been employed to reduce {HEAD ~ the levels} of RNase.  
For example , prolongation of the alkaline lysis step for { TAIL ~ 4 to 24 hours } together with the addition of lysozyme has been employed to reduce { HEAD ~ the levels } of RNase .
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH