除哪项外，APUD细胞与下列肿瘤的发生有关（）
A.胰岛细胞腺瘤
B.甲状腺髓样癌
C.乳腺髓样癌
D.肾上腺髓质肿瘤
E.肺燕麦细胞癌
参考答案：C
腰丛由____________、_____________构成，位于______间隙内，腰丛的阻滞点常取此间隙。
The store had to ________ a number of clerks because sales were down.
A．layout
B．layoff
C．layaside
D．laydown
