a prospective , double-blind , randomized , controlled clinical trial compared the efficacy and safety of fixed combinations of low-molecular weight heparin or standard unfractionated heparin plus dihydroergotamine mesylate in the prevention of deep vein thrombosis in high-risk patients undergoing elective major abdominal surgery .
C0019139
low-molecular weight heparin
C0019134
unfractionated heparin