Merge multiple row or column values into one row or column:

df.loc[colSelected,].apply(lambda x: ';'.join(x.astype(str)), axis=0)
df.loc[,rowSelected].apply(lambda x: ';'.join(x.astype(str)), axis=1)

Source:
https://stackoverflow.com/questions/33098383/merge-multiple-column-values-into-one-column-in-python-pandas