ATP是磷脂果糖激酶的底物，为什么ATP高于一定浓度时该酶催化的反应速度会下降？

罗斯福新政的中心措施( )。

A．对工业的调整

B．恢复银行信用

C．新建公共工程

D．对农业的调整

患者男，42岁。因“反复心前区疼痛2年，伴气短6个月”来诊。既往史无特殊。查体：T36.5℃，P95次/min，R28次/min，BP108/65mmHg。口唇无发绀，颈静脉怒张。HR95次/min，律不齐，偶有期前收缩，肺动脉瓣听诊区第二心音增强，胸骨右缘第3肋间可闻及持续的机械性杂音。双下肢轻度水肿。

需要在体外循环下修复瘘孔的情况有（）(提示 经治疗1周后患者症状有所缓解，准备行手术治疗。)

A.行瘘口切线缝合术有可能损伤血管壁引起大出血者

B.难于显露的瘘口

C.冠状动脉有明显病变须同期行主动脉-冠状动脉旁路移植者

D.合并心内畸形须同期手术矫正者

E.多发性瘘须经心腔、肺动脉或冠状动脉径路修补瘘口者

F.冠状动脉分支瘘或冠状动脉主干终末支瘘

Traditional Internet access methods like dial-up were so slow that host computers were connected to the dial-up （71） at the customer premise over slow （72） ports. PPP was designed to run directly over these serial links. But with the advent of broadband Internet （73）technologies such as ADSL and cable modems there has been a considerable increase in the bandwidth delivered to the end users. This means that the host computers at the customer premise connect to the （74） or cable "modem" over a much faster medium such as Ethernet.It also means that multiple （75） can connect to the Internet through the same connection.

75（）

A．cables

B．hosts

C．servers

D．modems

简述宋代话本小说的分类。

架棚支护安全注意事项有哪些？