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
1960 15
1961 17
1962 27
1963 41
1964 88
1965 84
1966 82
1967 265
1968 119
1969 127
1970 144
1971 187
1972 217
1973 218
1974 317
1975 282
1976 259
1977 291
1978 257
1979 290
1980 261
1981 242
1982 230
1983 232
1984 247
1985 257
1986 293
1987 279
1988 294
1989 295
1990 366
1991 471
1992 424
1993 464
1994 420
1995 457
1996 507
1997 469
1998 501
1999 351
2000 339
2001 316
2002 279
2003 331
2004 360
2005 335
2006 306
2007 355
2008 375
2009 372
2010 364
2011 365
2012 353
2013 396
2014 403
2015 491
2016 549
2017 599
2018 535
2019 486
2020 562
2021 561
2022 511
2023 358
2024 363
2025 85

Publication date

Text availability

Article attribute

Article type

Additional filters

Article Language

Species

Sex

Age

Other

Search Results

19,464 results

Results by year

Filters applied: . Clear all
Page 1
19,464 results
You have reached the last available page of results. Please see the User Guide for more information.