parenthetically       
adverb  formal uk/ˌpær.ənˈθet.ɪ.kəl.i/ us/ˌper.ənˈθet̬.ɪ.kəl.i/
 分开单独地|附带地
in a way that is in addition to the main part of what you are saying or writing
  Quotations from this text will be cited parenthetically. 出自本文的引用会分开单独收录。 
 I might add, parenthetically, that she was a great supporter of the party. 我要补充一点,附带说一下,她是我们党派的大力支持者。 
 See: parenthetical
 - More examples
 - "Not that I'm saying it's all over now," he said parenthetically.
 - It seems with young people, that the word "like" must be used parenthetically at least once in every sentence.
 - It should be noted parenthetically that the board asked for his support.