Google Scholar is a web search engine that broadly searches for published, scholarly literature. The results are not always full text and may be behind a paywall. Ask the library for help with accessing articles found through Google Scholar.
ScienceDirect provides access to a large database of scientific and medical research from the publisher Elsevier. While some resources are open source (available for free online) others may be behind a paywall.
PLOS One is a peer-reviewed open access scientific journal published by the Public Library of Science since 2006. The journal covers primary research from any discipline within science and medicine.
Trying to access a particular journal article that isn't available through school, your local public library, or the Boston Public Library databases? Try Illiad through the Boston Public Library. A free Boston Public Library E-Card is needed for use.