摘要
In order to obtain the intact nucleic acid of virus particles, on the basis of one-stepreleased method, two-step-released method and phages we have observed nucleic acid released from some sorts of insect virus particles under electron microscope. It has been found that under the condition of reacting on the urea of low concentration for a long time, the nucleic acid from four sorts of viruses could not only be released directly, but also be observed clearly.
