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【简答题】
是 人或高等动物体内的内分泌腺或内分泌细胞分泌的具有高度活性的有机物质,它们经过血液循环,作用于一定的器官、组织或细胞(分别称之为靶器官、靶组织、靶细胞),发挥调节作用,并通过反馈调节机制以维持内、外环境的适应与平衡。
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【单选题】some views in the old edition of Three Character Classic, some schools in Hubei Province demand to delete those sentences.
A.
Exposed to
B.
Opposed to
C.
Addicted to
D.
Accustomed to
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