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
1972 3
1973 24
1974 58
1975 52
1976 101
1977 95
1978 83
1979 82
1980 77
1981 98
1982 71
1983 88
1984 83
1985 92
1986 105
1987 102
1988 94
1989 114
1990 147
1991 151
1992 175
1993 174
1994 199
1995 191
1996 177
1997 200
1998 225
1999 226
2000 192
2001 199
2002 225
2003 219
2004 201
2005 244
2006 286
2007 269
2008 259
2009 245
2010 217
2011 223
2012 214
2013 206
2014 209
2015 214
2016 225
2017 168
2018 172
2019 150
2020 140
2021 96
2022 75
2023 60
2024 25

Text availability

Article attribute

Article type

Publication date

Search Results

7,549 results

Results by year

Filters applied: . Clear all
Page 1
7,549 results