For the points one 1 and 2 you could also use a hash:

my %hash = ( 1 => { desc=>'Alzheimer disease (5, 6)', keyword=>'alz'},
             2 => { desc=>'Something', keyword=>'bb' },
...);
[download]

And then you can loop over this hash for the print statement and also you don't need this long if elsif switch.

ciao knoebi