Which of the following cells down-regulates cellular immune response?
A. Th1 cell
B. DC
C. NK cell
D. Treg
E. B cell
查看答案
Cells that secrete perforin and granzyme are
A. CTLs and B cell
B. CTLs and NK cells
C. B cells and NK cells
D. CTLs and macrophages
E. B lymphocytes and macrophages
Which of the following is caused by type I hypersensitivity?
A. Hyperthyroidism
B. Urticaria (荨麻疹)
C. Serum Diseases
D. Contact dermatitis
E. Blood transfusion reaction
Complement-mediated hypersensitivity reactions include
A. Only type II hypersensitivity
B. Only type III hypersensitivity
C. Type I, II and III hypersensitivity reactions
D. Type IV hypersensitivity
E. Type II and Type III hypersensitivity reactions
公司准备组织优秀职工外出活动,在疗养、游览风景名胜或考察民俗三方面进行考虑,三者对旅游企业来说,属于
A. 愿望竞争者
B. 一般竞争者
C. 产品形式竞争者
D. 品牌竞争者
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