Area under curve (cell array)

Hi

I have the following cell array and I need to find the area under each vector (curve) [columns 1 and 2] between two points [columns 3 to 6]. Each vector is composed of number of cells (e.g. the first vector is composed of 39 cells) and each cell is composed to two elements (strain, stress). So I need the area under the curve just between (starin1, stress1) and (strain2, stress2). Please help.

summary3 =

Columns 1 through 3
                                               Strain1
  {1x39 cell}    {1x75 cell}    [ 7.669142585357160e-04]
  {1x75 cell}    {1x75 cell}    [-1.206232786783515e-04]
  {1x39 cell}    {1x41 cell}    [ 8.630787019556518e-04]
  {1x41 cell}    {1x65 cell}    [-2.445883525841570e-05]
  {1x65 cell}    {1x97 cell}    [ 9.109657363289406e-04]

Columns 4 through 6
     Strain2       stress1  stress2
  [-1.206232786783515e-04]    [150]   [ -40]    
  [     0.001808452047926]    [-40]   [ 330]    
  [-2.445883525841570e-05]    [170]   [ -20]    
  [ 9.109657363289406e-04]    [-20]   [ 180]    
  [-6.645138877833179e-04]    [180]   [-140]

[Jan]

What is the contents of e.g the {1x39 cell} in Strain1? Please explain this again.