With the exception of Google Scholar and PubMed, all of these databases (and most of the journal articles they index) are licensed by UC San Diego Library. As visitors, you can use them in the library, but you will not be able to access these off-campus.
If the article isn't available full-text within the database you're using, click on the orange UC-eLinks button to see if we have the article online elsewhere, usually at the journal publisher's website.
If we have the article online, 1) the article will open immediately, or 2) you'll get a list of options with Get It Online and a link to get to the article