To save specific citations from PubMed, select the checkboxes next to the citations. Choose Collections under the Send to: drop-down menu and click Add to Collections:
You will be prompted to log in to My NCBI (or sign up for a new account) and create a new collection or add the citations to an existing collection.
For more information about saving results in PubMed, see PubMed Help: Saving and E-mailing Results and Searches.
EndNote and RefWorks
To export citations from PubMed to EndNote or RefWorks, select the checkboxes next to the citations. Choose Citation Manager under the Send to: drop-down menu and click Create File:
Download the file to your computer and import it into EndNote or RefWorks (under Add a Reference > Import from a file > Select a file from your computer). For RefWorks you can also click the Save to RefWorks bookmarklet while viewing the PubMed results page.
To export citations from PubMed to the Zotero add-on in Firefox, look for the yellow folder icon in the address bar (you may need to select Zotero under the Tools menu). When the icon is clicked, a list of citations will appear.
Select the citations of interest and click OK.
Install the Save to Mendeley button on your bookmarks toolbar. Clicking on this button will bring up a list of citations. Select the plus sign next to the citations of interest to add them to My Library, or click Save All to save the entire list.