Polio vaccine attenuated vaccine strains. In 1958, the National Institutes of Health created a special committee on live polio vaccines. The various vaccines were carefully evaluated for their ability to induce immunity to polio, while retaining a low incidence of neuropathogenicity in monkeys. Large-scale clinical trials performed in the Soviet Union in late 1950s to early 1960s by Mikhail Chumakov and his colleagues demonstrated safety and high efficacy of the vaccine. Based on these results, the Sabin strains were chosen for worldwide distribution. Fifty-seven nucleotide substitutions distinguish the attenuated Sabin 1 strain from its virulent parent (the Mahoney serotype), two nucleotide substitutions
His Name Is Legs (Ladies and Gentlemen) Newmark, all of whom were part of Harrison's 1974 tour band. The song's arrangement reflects Harrison's adoption of the funk genre. As with the album's humorous artwork, the inclusion of "His Name Is Legs" on "Extra Texture" marked a rare example of light-heartedness among a collection of mostly downbeat songs. Several commentators view the track as an indulgence by Harrison. These detractors cite the in-joke nature of the composition, together with the largely unintelligible vocals on the recording. Harrison acknowledged that the song's appeal might be limited to "maybe two people". Although often noted for the serious, religious nature of