The circulation of RNA records in tissue areas by the utilization of radiolabeled, correlative oligonucleotides or ribonucleic acids ("riboprobes") is brought in situ hybridization histochemistry. Radioactive antecedents of DNA and RNA, [3H]-thymidine and [3H]-uridine individually, might be acquainted with living cells to decide the circumstance of a few periods of the cell cycle.
