PubMed is a free search engine accessing the MEDLINE database of references and abstracts on life sciences and biomedical topics. The United States National Library of Medicine at the National Institutes of Health maintain the database as part of the Entrez system of information retrieval. From 1971 to 1997, online access to the MEDLINE database had been through institutional facilities, such as university libraries. PubMed, first released in January 1996, ushered in the era of private, home- and office-based MEDLINE searching; the PubMed system was offered free to the public starting in June 1997. In addition to MEDLINE, PubMed provides access to: older references from the print version of Index Medicus, back to 1951 and earlier references to some journals before they were indexed in Index Medicus and MEDLINE, for instance Science, BMJ, Annals of Surgery recent entries to records for an article before it is indexed with Medical Subject Headings and added to MEDLINE a collection of books available full-text and other subsets of NLM records PMC citations NCBI BookshelfMany PubMed records contain links to full text articles, some of which are available in PubMed Central and local mirrors such as UK PubMed Central.

Information about the journals indexed in MEDLINE, available through PubMed, is found in the NLM Catalog. As of 27 January 2020, PubMed has more than 30 million citations and abstracts dating back to 1966, selectively to the year 1865, selectively to 1809; as of the same date, 20 million of PubMed's records are listed with their abstracts, 21.5 million records have links to full-text versions. Over the last 10 years, an average of nearly 1 million new records were added each year. 12% of the records in PubMed correspond to cancer-related entries, which have grown from 6% in the 1950s to 16% in 2016. Other significant proportion of records correspond to "chemistry", "therapy", "infection". In 2016, NLM changed the indexing system so that publishers are able to directly correct typos and errors in PubMed indexed articles. PubMed has been reported to include some articles published in predatory journals. MEDLINE and PubMed policies for the selection of journals for database inclusion are different.

Weaknesses in the criteria and procedures for indexing journals in PubMed Central may allow publications from predatory journals to leak into PubMed. Simple searches on PubMed can be carried out by entering key aspects of a subject into PubMed's search window. PubMed translates this initial search formulation and automatically adds field names, relevant MeSH terms, Boolean operators, and'nests' the resulting terms appropriately, enhancing the search formulation in particular by combining textwords and MeSH terms; the examples given in a PubMed tutorial demonstrate how this automatic process works: Causes Sleep Walking is translated as AND Likewise, soft Attack Aspirin Prevention is translated as AND AND A new PubMed interface was launched in October 2009 and encouraged the use of such quick, Google-like search formulations. By default the results are sorted by Most Recent, but this can be changed to Best Match, Publication Date, First Author, Last Author, Journal, or Title. For optimal searches in PubMed, it is necessary to understand its core component, MEDLINE, of the MeSH controlled vocabulary used to index MEDLINE articles.

They may require complex search strategies, use of field names, proper use of limits and other features. The search into PubMed's search window is only recommended for the search of unequivocal topics or new interventions that do not yet have a MeSH heading created, as well as for the search for commercial brands of medicines and proper nouns, it is useful when there is no suitable heading or the descriptor represents a partial aspect. The search using the thesaurus MeSH will give us fewer irrelevant results. In addition, it saves the disadvantage of the free text search in which the spelling, singular/plural or abbreviated differences have to be taken into consideration. On the other side, we will lose those articles more incorporated into the database to which descriptors have not yet been assigned. Therefore, to guarantee an exhaustive search, we must use a combination of controlled language headings and free text terms; when a journal article is indexed, numerous article parameters are extracted and stored as structured information.

Such parameters are: Article Type, Secondary identifiers, Country of the Journal or publication history. Publication type parameter allows searching by the type of publication, including reports of various kinds of clinical research

R2 expressway (Slovakia)

R2 is an expressway in Slovakia. It ends near Košice, it goes through or around Bánovce nad Bebravou, Prievidza, Žiar nad Hronom, Zvolen, Lučenec, Rimavská Sobota and Rožňava. The sections between Žiar nad Hronom and Zvolen are shared with R1 and R3. There is planned shared section between Ráztočno and Žiar nad Hronom with R3. From the total length of 303.8 km, these sections are in operation: 9.6 km Ruskovce - Pravotice 5.8 km Žiar nad Hronom bypass 18.2 km Zvolen, East - Kriváň 6.1 km Ožďany bypass 14.0 km Figa and Tornaľa bypass Highways portal by INEKO Institute Exit list of the sections opened in 2006

Echo Films

Echo Films is an American production company founded in April 2008 by American actress Jennifer Aniston and production partner Kristin Hahn. Echo Films has a production deal with Universal Pictures; the company produces projects for both television. Most of the projects star Jennifer Aniston; this is Jennifer Aniston's second production company. She found Plan B Entertainment with Brad Pitt and Brad Grey in 2002. In 2006, after Pitt and Aniston divorced, Grey became the CEO of Paramount Pictures, Pitt became the sole owner of the company. Kristin Hahn has another production company that she created in 2015 named Hahnscape Entertainment. On the choice of the projects Hahn said: "We like working from books and real-life stories about distinct characters that embody something relatable and relevant about human nature's double-sided coin of vulnerability and mettle." On the name of the company, Aniston add "We're drawn to stories about people finding their voice and finding their way because they help us as listeners and viewers do what we feel we're all trying to do, making sense of our lives through the stories of others.

That's why we chose the name Echo, to echo back an idea, a challenge, something that resonates through all of us." Chemistry, screenplay by David SussmanCounter-Clockwise, screenplay by Paul BernbaumFirst Ladies, screenply by Tig Notaro and Stephanie Allynne, with Tig NotaroGetting Rid of Matthew, based on the novel of Jane Fallon and adapted by Jane FallonLove: Todd, screenplay by Kristen StavolaSignificant Other, directed by Jason BatemanThe Divorce Party, based on the novel of Laura Dave, adapted by Gwyn LurieThe Fixer, directed by James GrayThe Goree Girls, screenplay by John Lee Hancock & Margaret Nagle, directed by Mimi Leder with Ellen Pompeo, Sandra Oh, Jennette McCurdy, Jennifer Landon, Kelly Rowland, Pam Tillis, Melissa DiMarco, Jimmy Bennett, Laura Breckenridge, Cristine RoseUntitled Aniston/Goodhart Comedy Project, directed by Sophie GoodhartWhat Alice Forgot, directed by David Frankel Echo Films on IMDb