Request for article (yellow fever research)

I am an independent biochemical biological researcher. I am looking for a way to access scientifcic papers on the biochemical activity of plant medicines inside of the human body. I live in Sao Paulo, Brasil, close to the atlantic forest.

An example of a paper: https://www.researchgate.net/publication/26554835_Brazilian_medicinal_plants_used_by_the_Dr_Joao_Ferreyra_da_Rosa_according_to_his_Treatise_on_Pestilence_in_Pernambuco_at_the_end_of_the_17th_century