患者，女，24岁。主诉：上唇部肿胀。既往史：起床时偶然发现上唇部肿胀，入睡前上唇并无异常感觉。查：以上唇为中心可见弥漫性肿胀，肿胀处按之可触及硬结，无疼痛等自觉症状。肿胀持续数小时后完全消失。实验室检查无明显异常。

本病的病因是（）

A.细菌感染

B.病毒感染

C.自主神经紊乱

D.遗传因素

E.变态反应

China is to send its top negotiator on North Korea’s nuclear program to Pyongyang (36) amid international concern over the launch of (37) .
While the (38) and its ally Japan push for (39) against North Korea, China is (40) , not sanctions.
Also, the (41) to Japan says sanctions on North Korea will (42) efforts to bring the secluded state back to (43) on its nuclear program.
North Korea (44) the six-party talks in (45) after Washington imposed financial sanctions for alleged counterfeiting and (46) activities.
A broadcast on North Korean State Television (47) the missile tests, in what it called a "successful (48) ".
It said North Korea will take action against anyone who (49) them.
The Minister is reported to have told a (50) that the missile launches were (51) because of America’s sanctions against Pyongyang.
North Korea remains (52) in the face of international condemnation and has warned (53) could be carried out.
UN Security Council members will (54) discussions tonight on whether a (55) condemning the missile launches should call for sanctions.