TABLE OF CONTENTS
Volume 20, Issue 3 (May/June 2008)
Reviews
The relationship between hypogonadism and erectile dysfunction
T I S Hwang and Y-C Lin
Int J Impot Res 20: 231-235; advance online publication, February 28, 2008; doi:10.1038/sj.ijir.3901633
Erectile dysfunction as a harbinger for increased cardiometabolic risk
K L Billups, A J Bank, H Padma-Nathan, S D Katz and R A Williams
Int J Impot Res 20: 236-242; advance online publication, January 17, 2008; doi:10.1038/sj.ijir.3901634
Stem and endothelial progenitor cells in erection biology
T D Strong, M A Gebska, H C Champion, A L Burnett and T J Bivalacqua
Int J Impot Res 20: 243-254; advance online publication, February 7, 2008; doi:10.1038/sj.ijir.3901635
Original Articles
Relaxant effects of an alkaloid-rich fraction from Aspidosperma ulei root bark on isolated rabbit corpus cavernosum
A R Campos, K M A Cunha, F A Santos, E R Silveira, D E A Uchoa, N R F Nascimento and V S N Rao
Int J Impot Res 20: 255-263; advance online publication, November 29, 2007; doi:10.1038/sj.ijir.3901624
The application of quantitative methods for identifying and exploring the presence of bias in systematic reviews: PDE-5 inhibitors for erectile dysfunction
G E Bekkering, A M Abou-Setta and J Kleijnen
Int J Impot Res 20: 264-277; advance online publication, December 6, 2007; doi:10.1038/sj.ijir.3901626
Role of the soluble guanylyl cyclase 
1-subunit in mice corpus cavernosum smooth muscle relaxation
S Nimmegeers, P Sips, E Buys, K Decaluwé, P Brouckaert and J Van de Voorde
Int J Impot Res 20: 278-284; advance online publication, December 6, 2007; doi:10.1038/sj.ijir.3901627
The engineering analysis of bioheat equation and penile hemodynamic relationships in the diagnosis of erectile dysfunction: part I—theoretical study and mathematical modeling
W K Ng, E Y K Ng and S J Chia
Int J Impot Res 20: 295-306; advance online publication, December 13, 2007; doi:10.1038/sj.ijir.3901629
The engineering analysis of bioheat equation and penile hemodynamic relationships in the diagnosis of erectile dysfunction: part II—model optimization using the ANOVA and Taguchi method
E Y K Ng, W K Ng, J Huang and Y K Tan
Int J Impot Res 20: 285-294; advance online publication, December 13, 2007; doi:10.1038/sj.ijir.3901628
Vascular endothelial growth factor (VEGF) gene therapy using a nonviral gene delivery system improves erectile function in a diabetic rat model
J E Dall'Era, R B Meacham, J N Mills, S Koul, S N Carlsen, J B Myers and H K Koul
Int J Impot Res 20: 307-314; advance online publication, February 14, 2008; doi:10.1038/ijir.2008.1
Evidence for the existence of an estrogen-responsive sexually dimorphic group of cells in the medial preoptic area of the 129SvEv mouse strain
R A Hill, E R Simpson and W C Boon
Int J Impot Res 20: 315-323; advance online publication, February 14, 2008; doi:10.1038/ijir.2008.2
Evaluation of an internet-based psychological intervention for the treatment of erectile dysfunction
M P McCabe, E Price, L Piterman and D Lording
Int J Impot Res 20: 324-330; advance online publication, February 28, 2008; doi:10.1038/ijir.2008.3
Letters to the Editor
Response to: Efficacy of changing testosterone gel preparations (Androgel or Testim) among suboptimally responsive hypogonadal men
A Morgentaler
Int J Impot Res 20: 331; doi:10.1038/ijir.2008.5