选择题：为会计核算提供了必要手段的会计假设是（　　）。

与Th细胞活化、增殖、分化无关的成分是A.IL－1B.MHC－Ⅱ类分子C.IL－2D.APCE.补体

It is said that this job is open to all,____previous experience. A.regardless of B.prior to C.because of D.in case of

单项扩散试验中双环现象产生的原因是A.出现了抗原性相同、扩散率不同的组分B.抗体不纯C.抗原不纯D

资料：When we see well，we do not think about our eyes very often. It is only when we cannot see perfectly that we realize how important our eyes are. People who are near-sighted can only see things that are very close to their eyes，Everything else seems blu

浆细胞白血病的临床诊断标准是A.外周血白细胞分类浆细胞>20%和绝对值>2×109??／L??B.外周血白细胞