1. Effects of tibolone on plasma levels of nitric oxide in postmenopausal women 
Ettore Cicinelli, M.D., Louis J Ignarro, M.D., Pietro Galantino, M.D., Vincenzo Pinto, M.D., Bruno Barba, M.D., Sergio Schonauer, M.D. 
Fertility and Sterility 
Volume 78, Issue 3, Pages (September 2002)
DOI: /S (02)

2. FIGURE 1
Plasma levels of nitrite and nitrate, the nitric oxide (NO) stable metabolites, in nine women treated for 1 month with tibolone 2.5 mg/day and with placebo for the following month (group A) (solid bars) and in nine women receiving inverted treatment (group B) (open bars). Data are means + SD. An asterisk at month 1 indicates that the differences between NO mean values in group A and group B and between month 1 and baseline values in group A are statistically significant; conversely, an asterisk at month 2 indicates that levels in group B are higher than at baseline and in group A.
Cicinelli. Tibolone and NO in menopausal women. Fertil Steril 2002.
Fertility and Sterility  , DOI: ( /S (02) )