在初生根的横切面上，初生木质部和初生韧皮部各三束，故为“六原型”。

So great was the influence of Thomas Paine on his time that John Adams suggested that the era was called "The Age of Paine".

典型十二指肠球部溃疡的腹痛规律是（）

A.无明显规律性

B.疼痛一排便一加重

C.进食一疼痛一缓解

D.疼痛一进食一缓解

E.疼痛一便意一缓解

试述颈段脊髓受损的临床表现。

NB_TS_MPDCH=4，则有（）PCCCH信道

A.2

B.1

C.3

D.4

装置中设备散热量与外界风速有关。