问题 单项选择题

洋地黄酊中主成分不稳定的主要原因在于其易()。

A.水解

B.氧化

C.异构化

D.聚合

E.脱羧

答案

参考答案:A

解析:本题考查的要点是"药物的化学降解类型"。洋地黄酊易水解,多采用70%乙醇浸出。穿心莲内酯在pH值为7时内酯环水解极其缓慢,在偏碱性溶液中则水解加快。具有酚羟基或潜在酚羟基的有效成分易氧化,如黄芩苷。

判断题
填空题

Stress is our response to threatening or (1) events. We may experience different levels of stress depending on the (2) , meaning the events or circumstances that cause us to feel stress. Stressors can be classified into (3) main categories: (4) events, personal stressors, and (5) stressors. Cataclysmic events are major events that cause stress (6) , immediately, for a great many people at once. Personal stressors are major life events that create stress, including (7) life events. Background stressors are (8) hassles, or minor irritations, or (9) background stressors. Repeated exposure to stressors has both psychological and (10) consequences. The long- term consequence is that body tissues such as the heart and blood vessels can begin to (11) . The (12) system functions less effectively, and (13) our ability to fight off illnesses.
The General Adaptation (14) explains the sequence of physiological reactions to stress. There are three phases to G. A. S. The first is the " alarm and (15) " phase: we respond with alarm, and take (16) to remove the stressor. The second phase is the (17) stage: we fight against the stressor or try to cope with the stressor. This can lead to the third phase. (18) . The exhaustion phase may be an (19) way of trying to avoid the stressors. The body may be telling us that we need to do whatever is (20) to remove the stressor.

Stress is our response to threatening or (1) events. We may experience different levels of stress depending on the (2) , meaning the events or circumstances that cause us to feel stress. Stressors can be classified into (3) main categories: (4) events, personal stressors, and (5) stressors. Cataclysmic events are major events that cause stress (6) , immediately, for a great many people at once. Personal stressors are major life events that create stress, including (7) life events. Background stressors are (8) hassles, or minor irritations, or (9) background stressors. Repeated exposure to stressors has both psychological and (10) consequences. The long- term consequence is that body tissues such as the heart and blood vessels can begin to (11) . The (12) system functions less effectively, and (13) our ability to fight off illnesses.
The General Adaptation (14) explains the sequence of physiological reactions to stress. There are three phases to G. A. S. The first is the " alarm and (15) " phase: we respond with alarm, and take (16) to remove the stressor. The second phase is the (17) stage: we fight against the stressor or try to cope with the stressor. This can lead to the third phase. (18) . The exhaustion phase may be an (19) way of trying to avoid the stressors. The body may be telling us that we need to do whatever is (20) to remove the stressor.