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.
Distemper is a crude form of tempera made by mixing dry pigment into a paste with water, which is thinned with heated glue in working or by adding pigment to whiting (a mixture of fine-ground chalk and size). It is used for stage scenery and full-size preparatory cartoons for murals and tapestries.