Couldn't generate code for the following reason:
Encountered unsupported operator partialdiff; 
  In MathML apply element with ID J11_calculation.
  In MathML math element.
  In CellMLComponent element with name calcium_current.
  In Model element with cmeta:id mosekilde_lading_yanchuk_maistrenko_2001_version01 with name mosekilde_lading_yanchuk_maistrenko_2001_version01.