Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation

Search Page

Filters

My NCBI Filters

Results by year

Table representation of search results timeline featuring number of search results per year.

Year Number of Results
1967 1
1974 1
1986 1
1987 7
1988 5
1989 36
1990 101
1991 106
1992 105
1993 130
1994 156
1995 150
1996 142
1997 172
1998 229
1999 238
2000 263
2001 317
2002 391
2003 406
2004 495
2005 457
2006 463
2007 491
2008 483
2009 529
2010 468
2011 412
2012 369
2013 355
2014 320
2015 305
2016 289
2017 241
2018 237
2019 193
2020 188
2021 160
2022 72
2023 42
2024 23

Text availability

Article attribute

Article type

Publication date

Search Results

8,764 results

Results by year

Filters applied: . Clear all
Page 1
8,764 results
-