邮政，电报和电话

Postal Telegraph and Telephone在美国地区以外的电话服务提供者 Public Telephone & Telegraph公用电话和电报 Push To Talk单键讲话 Public Telephone and Telegraph公共电话电报，类似于PSTN。 protein truncation test错配接合蛋白质截短测试法 Postal, Telegraph and Telephone邮政，电报和电话 Professional Trainer Training职业培训师的培训 Project Tracking Tool项目跟踪工具 Professional Technical Trainer专业技术的教练 Property Transfer Tax产权转让税 Platform Transmitter Terminal平台的终端。发射机 Post Telephone and Telegraph邮政电话和电报 Physical Training Test体育锻炼测试 Petroleum Authority of Thailand (Bangkok, Thailand)石油部门泰国(泰国首都曼谷) Pittsburg Tank & Tower Company Inc.美国坦克和塔公司