re = /\b(?:MIM#|OMIM:|(?<!:))(\d{6})\b/m
str = '111111;Dystonia-1,222222,OMIM:555555; 3333333 Dystonic disorder1,MIM#444444'
# Print the match result
str.scan(re) do |match|
puts match.to_s
end
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html