fluctuations
It is believed that most patients on long-term levodopa therapy will,        sooner or later, develop response fluctuations of varying types and severity       (Riley and Lang, 1993).
It is believed that most  @OBJECT$  on long-term levodopa therapy will,        sooner or later,  @PREDICAT$  response  @SUBJECT$  of varying types and severity       (Riley and Lang, 1993).