Yes / no in Syrian Arabic.

regional variants of Arabic

As I have noted before the Arabic language has many regional forms along with Modern Standard Arabic (MSA).

One of them is Syrian Arabic which belongs to the bigger regional group of Levantine Arabic. Other members of the same group have their own variations and influences. 

For example Lebanese Arabic- another member of Levantine Arabic is influenced a lot by French probably due to the Crusader States in the region during Medieval  times and its French colonial past.

French colonial Middle East.

So,yes in Syrian Arabic is 
اي

eh

yes

لاء

la' (with a glottal stop)

no

Some people say la without  a glottal stop

لا

la

no

cultural note 

Arabs move their head upwards to say no, unlike westerners who move their head sideways.

So,pay attention to the body language, too.