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 an infection that can cause dogs to seize. If your dog has not been vaccinated against distemper, then this could be the reason for the seizure. Vaccines. Although vaccines are essential to keeping your pet safe from nasty diseases, they do on occasion cause convulsions when an animal is genetically predisposed to such occurrences. If this is the case for your dog, vaccinations can be managed in a way that reduces the risk of seizure.