1·对于欧洲各国的探险来说，公元1453年土耳其攻陷君士坦丁堡是个关键时期。
The fall of Constantinople to the Ottoman Empire in 1453 was a pivotal reason for European exploration.
2·欧洲历史上的古代与文艺复兴之间的时期，通常被认为是从公元476年到1453年。
The period in European history between antiquity and the Renaissance, often dated from a. d. 476 to 1453.
3·方法：对52例慢性牙周炎患者的1453颗牙进行龈下刮治及根面平整术，随访3个月。
METHODS: 1453 teeth of 52 patients with chronic periodontitis were given scaling and root-planing procedures.
4·1453年君士坦丁堡的陷落所造成的震动，仍然笼罩着大部分西方世界，这一事件似乎孕育着更多的东西。
Over much of the western world there still hung the shock of the fall of Constantinople in 1453, an event which seemed the more pregnant.
5·采用实验研究法对1453名中学生进行为期5个月的体育与健康运动处方的干预教育。
With the experimental research method, 1453 middle school students receive the intervention education of sport and health prescription for 5 months.
6·侧重于君士坦丁堡330和1453之间的艺术，这本书探讨的基本动机和社会产生如此丰富而微妙的艺术形式和态度。
Focusing on the art of Constantinople between 330 and 1453, this book probes the underlying motives and attitudes of the society which produced such rich and delicate art forms.