You can load
into a variable (preferably a cell array)
results = cell( 2, 4 ); % allocate
for testi=1:2
for resi = 1:4
filename = sprintf('results_test%d_%d.mat', testi, resi );
results{testi,resi} = load( filename );
end
end
Now you have all the results stored in results
cell array and you may access the stored variables, e.g.,
results{1,3}.someVar % access variable someVar (assuming such variable was saves to the corresponding mat file