Only in the 1990s was their actual mechanism of action demonstrated.

What the other mechanisms of action are is still unknown.

We also know that their mechanisms of action are not the same in every species.

They are, however, entirely different drugs, with separate mechanisms of action.

The proposed mechanism of action is depicted in figure 3.

First, it was said to have a unique mechanism of action.

The side effects are often associated with the medication's mechanism of action.

The mechanism of action within the body will be the same, producing similar side effects.

For at least one significant use, the mechanism of action is unclear.

"Further research to determine the mechanism of action is required, however the results are very encouraging."