1Goldstein I, Lue TF, Padma-Nathan H, et al. Oral sidenafil in the treatment of erectile dysfunction[ J]. N Engl J Med, 1998,338 (20) :1397-1404.
2Atiemo HO, Szostak M J, Sklar GN, et al. Salvage of sildenafil failures referred from primary care physicians [ J ]. Urology,2003, 170(6 Pt 1) :2356-2358.
3Jian BP, Yu CC, Su CC, et al. Rechallenge prior sildenafil nonresponders[J]. Int J Impot Res, 2004, 16(1) :64-68.
4Basu A, Ryder RE. New treatment options for erectile dysfunction in patients with diabetes mellitus [ J ]. Drugs, 2004, 64 ( 23 ):2667-2688.
5McCullough AR, Barada JH, Fawzy A, et al. Achieving treatment optimization with Viagra in patients with ED [ J ]. Urology,2002, 60(2 Suppl 2) :28-38.
4Attino T M, Malatino L S.Phosphodiesterase type5 inhibition reverse impaired forearm exercise induced vasodilatation in hypertensive patients[J].J Hypertens, 2008, 26 ( 3 ) : 501.
5Chau E M C, Fan K Y Y.Effect of chronic sildenafil in parients with Eisenmenger syndrome versus idiopathic pulmonary arterial hypertension[J].Jeardiol, 2007, I20 ( 3 ) : 301-305.
6Duong HT, Comhair SA, Aldred MA, et al. Pulmonary artery en- dothelium resident endothelial colony-forming ceils in pulmonary arterialhypertension[J]. Pulm Circ, 2011, 1:475-486.
7Sastry BK,Narasimban C, Reddy NK,et al. Clinical effi- cacy of sildenafil in primary pulmonary hyperteasion a ran- domized placebo-controlled ,double-blind ,crossover study[J].AM Coil Cardiol,2010,43(7):1149-1153.