Given a passage with a question and an answer to that question, classify if the answer actually answers the question into 'yes' or 'no'. Output 'yes' if the answer answers the question and output 'no' if the answer does not answer the question.
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Question: Question: Is kREX2 essential for either procyclic or bloodstream form Trypanosoma brucei?
Answer: KREX2 is a U-specific exonuclease that is dispensable for RNA editing in vivo in T. brucei BFs and PFs. This result suggests that the U deletion activity, which is required for RNA editing, is primarily mediated in vivo by KREX1 which is normally found associated with only one type of editosome. The retention of the KREX2 gene implies a non-essential role or a role that is essential in other life cycle stages or conditions.

Answer: no

Question: Question: Do an update in the palliative management of malignant dysphagia?
Answer: Palliative treatment for oesophageal cancer should be individualized and relate to tumour stage, size and location, the patient's medical condition and his/her personal wishes. The palliative treatment largely includes self-expanding metal stents (SEMS), laser (including photodynamic therapy (PDT)) or a combination of the two to relieve symptoms, this may be employed with or without other treatments such as radiotherapy/chemotherapy (RT/CT) with the aim of reducing tumour bulk and possibly prolonging survival. A multi-disciplinary approach is vital in patients with advanced oesophageal cancer.

Answer: yes

Question: Question: Is helicobacter pylori associated with the manifestations of gastroesophageal reflux disease?
Answer: Helicobacter pylori plays no role in the pathogenesis of gastroesophageal reflux disease or its complications.

Answer:
no