Summary Seventeen strains of C virus representing 16 different antigenic varieties were tested for their capacity to remain active or multiply following consecutive passages in embryonated eggs inoculated on the chorioallantoic membrane. Viral activity was demonstrated in suckling mice with membranes infected by each of 10 strains after one egg passage, by 5 strains after an additional passage, by 3 strains after 3 passages and by one strain (Easton-10) after 5 passages. The findings indicated that multiplication of the Easton-10 virus had occurred.
Summary A technic has been described for the study of the excitability cycle of the heart employing permanent implantation of electrodes.
Main conclusion ::: Contrasting patterns of histone modifications between the X and Y chromosome in Silene latifolia show euchromatic histone mark depletion on the Y chromosome and indicate hyperactivation of one X chromosome in females.