一本有关强迫症的书,这一段求翻译

一本有关强迫症的书,这一段求翻译
Each subtype of OCD can occur by itself or in concert with other categories of
obsessions and compulsions. It is not unusual to have a mix of symptoms or
for OCD to morph and change over time. Having a mix of symptoms can make
treatment a little more challenging, but certainly not impossible.
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