entrez_citmatch         Fetch pubmed ids matching specially formatted
                        citation strings
entrez_db_links         List available links for records from a given
                        NCBI database
entrez_db_searchable    List available search fields for a given
                        database
entrez_db_summary       Retrieve summary information about an NCBI
                        database
entrez_dbs              List databases available from the NCBI
entrez_fetch            Download data from NCBI databases
entrez_global_query     Find the number of records that match a given
                        term across all NCBI Entrez databases
entrez_info             Get information about EUtils databases
entrez_link             Get links to datasets related to records from
                        an NCBI database
entrez_post             Post IDs to Eutils for later use
entrez_search           Search the NCBI databases using EUtils
entrez_summary          Get summaries of objects in NCBI datasets from
                        a unique ID
extract_from_esummary   Extract elements from a list of esummary
                        records
linkout_urls            Extract URLs from an elink object
parse_pubmed_xml        Summarize an XML record from pubmed.
set_entrez_key          Set the ENTREZ_KEY variable to be used by all
                        rentrez functions
