中心骨髓活性受抑制是下列哪种血液病骨髓显像的典型征象（）。
A.再障
B.急性白血病
C.慢性溶血性贫血
D.真性红细胞增多症
E.霍奇金病
参考答案：B
如图4所示，甲是研究平抛运动的装置，乙是试验后在白纸上作的图(0点是抛出点).
(1).实验前应调节斜槽末端水平，是为了保证小球抛出时
(2).每次让小球从同一位置由静止释放，是为了保证每次小球抛出时_______________ _.
(3)该平抛运动的初速度 m/s.(g=9.8m/s)
A 35-year-old female client who complains of weight gain, facial hair, absent menstruation, frequent bruising, and acne is diagnosed with Cushing's syndrome. Cushing's syndrome is most likely caused by which of the following
A．An ectopic corticotropin-secreting tumor.
B．Adrenal carcinoma.
C．A corticotropin-secreting pituitary adenoma.
D．An inborn error of metabolisrn.
该平抛运动的初速度 m/s.(g=9.8m/s)