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
1966 1
1967 2
1968 3
1971 1
1973 4
1974 53
1975 106
1976 91
1977 91
1978 85
1979 114
1980 77
1981 72
1982 69
1983 57
1984 67
1985 69
1986 64
1987 60
1988 68
1989 64
1990 75
1991 66
1992 73
1993 58
1994 50
1995 39
1996 30
1997 41
1998 42
1999 49
2000 61
2001 52
2002 62
2003 40
2004 66
2005 56
2006 70
2007 53
2008 69
2009 73
2010 74
2011 66
2012 56
2013 64
2014 55
2015 61
2016 54
2017 61
2018 60
2019 35
2020 40
2021 42
2022 10
2023 11
2024 16

Text availability

Article attribute

Article type

Publication date

Search Results

2,919 results

Results by year

Filters applied: . Clear all
Page 1
2,919 results
-