双重免疫组织化学染色的原理是（）

A.在两张切片或细胞学涂片上，同时或先后对两种抗原进行染色，标记物不同

B.在两张切片或细胞学涂片上，先后对两种抗原进行染色，标记物相同

C.在同一张切片或细胞学涂片上，同时或先后对两种抗原进行染色，标记物不同

D.在同一张切片或细胞学涂片上，先后对两种抗原进行染色，标记物相同

E.在两张连续切片上同时对两种抗原进行染色，标记物不同

A client with coronary artery disease reports intermittent chest pain that occurs with exertion. The physician prescribes sublingual nitroglycerin. When teaching the client about nitroglycerin administration, the nurse should include which instruction（）

A. "Be careful after taking nitroglycerin because it may cause dizziness. "

B. "Make sure you replace your nitroglycerin tablets every 6 months to ensure potency. "

C. "A burning sensation after taking nitroglycerin indicates medication potency. "

D. "When you experience chest pain, take one tablet every 30 minutes until the pain is relieved. "