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 Custom Filters

Results by year

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

Year Number of Results
1955 40
1956 69
1957 93
1958 122
1959 171
1960 177
1961 209
1962 245
1963 228
1964 256
1965 268
1966 286
1967 296
1968 285
1969 306
1970 370
1971 371
1972 416
1973 380
1974 368
1975 385
1976 449
1977 477
1978 437
1979 478
1980 447
1981 498
1982 424
1983 425
1984 380
1985 370
1986 372
1987 388
1988 459
1989 452
1990 528
1991 639
1992 637
1993 640
1994 661
1995 765
1996 646
1997 568
1998 550
1999 536
2000 595
2001 497
2002 465
2003 539
2004 498
2005 564
2006 719
2007 692
2008 669
2009 623
2010 556
2011 443
2012 410
2013 469
2014 528
2015 477
2016 427
2017 398
2018 379
2019 319
2020 217
2021 227
2022 186
2023 241
2024 304

Publication date

Text availability

Article attribute

Article type

Additional filters

Article Language

Species

Sex

Age

Other

Search Results

27,493 results

Results by year

Filters applied: . Clear all
Page 1
27,493 results
You have reached the last available page of results. Please see the User Guide for more information.