[单选题]实施清创术的最佳时机应该是()
A.伤后2~4小时内进行
B.伤后4~6小时内进行
C.伤后6~8小时内进行
D.伤后8~12小时内进行
E.在应用抗生素的情况下可延至24小时

{{B}}US Signs Global Tobacco Treaty{{/B}}
1 The United States has taken the first step toward approving a global tobacco treaty that promises to help control the deadly effects of tobacco use throughout the world. Health and Human Services Secretary Tommy Thompson signed the Framework Convention on Tobacco Control (FCTC) this week at the United Nations. The Senate must still approve the treaty before the US can implement its provisions.
2 The FCTC was developed by the World Health Organization and approved by members of the World Health Assembly, including the United States, last year. Countries that ratify it would be required to enact strict tobacco control policies.
3 For instance, cigarettes sold in those countries would have to have health warnings on at least 30