But it’s a study way back in 1999 that actually offers a possible explanation for these counterintuitive findings: “the antigenic distance hypothesis.” That is, the more different a particular vaccine’s strains are from the previous year, the more effective the vaccine is likely to be (assuming the vaccine strains match the circulating strains that year). But vaccine strains that are more similar to the previous year’s vaccine strains — such as last year’s H3N2 A strain, identical to the strain in the 2013-2014 season’s vaccine — may end up less effective, and we did see very low effectiveness last year because of the H3N2 strain.
And now please welcome President Abraham Lincoln.
Good morning. Just a second while I get this connection to work. Do I
press this button here? Function-F7?
No, that's not right. Hmmm. Maybe I'll have to reboot. Hold on a minute.
Um, my name is Abe Lincoln and I'm your president. While we're waiting, I want to thank Judge David Wills,
chairman of the committee supervising the dedication of the Gettysburg cemetery.
It's great to be here, Dave, and you and the committee are doing a great
job. Gee, sometimes this new technology does have
glitches, but we couldn't live without it, could we? Oh - is it ready? OK, here we go:
Click here to start
Table of Contents Gettysburg Cemetery Dedication
The most commonly used AAS in medicine are testosterone and its various esters (but most commonly testosterone undecanoate , testosterone enanthate , testosterone cypionate , and testosterone propionate ),  nandrolone esters (most commonly nandrolone decanoate and nandrolone phenylpropionate ), stanozolol , and metandienone (methandrostenolone).  Others also available and used commonly but to a lesser extent include methyltestosterone , oxandrolone , mesterolone , and oxymetholone , as well as drostanolone propionate , metenolone (methylandrostenolone), and fluoxymesterone .  Dihydrotestosterone (DHT; androstanolone, stanolone) and its esters are also notable, although they are not widely used in medicine.  Boldenone undecylenate and trenbolone acetate are used in veterinary medicine .