端面铣削时，若铣床主轴与进给方向不垂直，则相当于用一个倾斜的圆环将工件表面切出一个（

If he____ that he____ to work there then, everything would be OK now.

[      ]

A. insisted; be sent

B. insisted; was sent

C. had insisted; be sent

D. had insisted; was sent

—Don’t you know your computer has been inflected with viruses?

— Really？No wonder it hasn’t_______ as properly as before.

A．managed

B．controlled

C．operated

D．appeared

符合再生障碍性贫血诊断的是

A．全血细胞减少

B．骨髓增生低下，三系减少

C．血清铁及骨髓细胞内外铁均减少

D．肝、脾和淋巴结不大

E．有出血倾向

下列哪项不是检验幽门螺杆菌的常用方法（）

A.血培养

B.快速尿素酶试验

C.胃粘膜组织切片染色

D.呼气试验

E.血清抗幽门螺杆菌抗体检测

在下列哪种条件下贮藏果实的效果好（）

A.高二氧化碳浓度、低氧浓度和高乙烯浓度

B.低二氧化碳浓度、高氧浓度和无乙烯

C.低氧浓度、高二氧化碳浓度和无乙烯

D.无氧、无乙烯和高二氧化碳浓度