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
1946 2
1948 2
1950 5
1951 12
1952 7
1953 4
1954 1
1955 16
1956 3
1957 5
1958 5
1959 4
1960 4
1961 3
1962 11
1963 18
1964 15
1965 13
1966 31
1967 34
1968 28
1969 50
1970 33
1971 29
1972 26
1973 29
1974 40
1975 34
1976 36
1977 45
1978 38
1979 44
1980 33
1981 50
1982 54
1983 39
1984 47
1985 56
1986 64
1987 69
1988 57
1989 50
1990 59
1991 82
1992 99
1993 113
1994 99
1995 100
1996 92
1997 130
1998 119
1999 123
2000 174
2001 136
2002 154
2003 161
2004 239
2005 156
2006 228
2007 257
2008 240
2009 319
2010 340
2011 318
2012 393
2013 388
2014 447
2015 472
2016 435
2017 415
2018 447
2019 458
2020 356
2021 253
2022 132
2023 88
2024 107

Search Results

8,698 results

Results by year

Filters applied: . Clear all
Page 1
8,698 results