So a 74xx244 works at a commercial operating temperature, while a 54xx244 which is the same logic device [maybe the same pinout, and package] will continue to operate to the military operating temperature range [which is wider].
A distemper vaccine is more than a preventive against canine distemper virus. This vaccine, considered a core vaccine for all dogs in the United States, also protects against a host of other diseases you may not know your dog is susceptible to. These can include adenovirus, parvovirus, and others.
DHPP. DHPP is a combination vaccine for distemper, hepatitis, pavovirus and parainfluenza. Canine distemper is a virus that affects a dog's respiratory, gastrointestinal and central nervous system. There is no cure. Canine hepatitis attacks the liver, eyes and kidneys. Death can occur.