In this task, you are given a sentence from the research paper and your task is to classify the given sentence into the following categories: Background (Why is this problem important? What relevant works have been created before? What is still missing in the previous works? What are the high-level research questions? How might this help other research or researchers?), Purpose (What specific things do the researchers want to do? What specific knowledge do the researchers want to gain? What specific hypothesis do the researchers want to test?), Method (How did the researchers do the work or find what they sought? What are the procedures and steps of the research?), or Finding (What did the researchers find out? Did the proposed methods work? Did the thing behave as the researchers expected?). 

Q: In the current study , we reported concurrent up-regulation of adenovirus E1a-associated 300 kDa protein p300 and GFAP in Tat-expressing human astroytoma cells and primary astrocytes.

A: finding
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Q: The low pH environment of the endosome facilitates passage of the viral genome into the cytoplasm.

A: background
****
Q: Methods Patients with COVID-19 pneumonia ( confirmed by next-generation sequencing or RT-PCR ) who were admitted to one of two hospitals in Wuhan and who underwent serial chest CT scans were retrospectively enrolled.

A:
method
****