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

Literature

PubMed

PubMed® comprises more than 37 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full text content from PubMed Central and publisher web sites.

Featured Bookshelf titles

LiverTox

Clinical and Research Information on Drug-Induced Liver Injury

Browse the Bookshelf

Literature databases

Bookshelf

Books and reports

MeSH

Ontology used for PubMed indexing

NLM Catalog

Books, journals and more in the NLM Collections

PubMed

Scientific and medical abstracts/citations

PubMed Central

Full-text journal articles

Data

Genes

Gene sequences and annotations used as references for the study of orthologs structure, expression, and evolution

Gene

Collected information about gene loci

GEO DataSets

Functional genomics studies

GEO Profiles

Gene expression and molecular abundance profiles

PopSet

Sequence sets from phylogenetic and population studies

Proteins

Protein sequences, 3-D structures, and tools for the study of functional protein domains and active sites

Conserved Domains

Conserved protein domains

Identical Protein Groups

Protein sequences grouped by identity

Protein

Protein sequences

Protein Family Models

Models representing homologous proteins with a common function

Structure

Experimentally-determined biomolecular structures

BLAST

A tool to find regions of similarity between biological sequences

blastn

Search nucleotide sequence databases

blastp

Search protein sequence databases

blastx

Search protein databases using a translated nucleotide query

tblastn

Search translated nucleotide databases using a protein query

Primer-BLAST

Find primers specific to your PCR template

Genomes

Genome sequence assemblies, large-scale functional genomics data, and source biological samples

Assembly

Genome assembly information

BioCollections

Museum, herbaria, and other biorepository collections

BioProject

Biological projects providing data to NCBI

BioSample

Descriptions of biological source materials

Genome

Genome sequencing projects by organism

Nucleotide

DNA and RNA sequences

SRA

High-throughput sequence reads

Taxonomy

Taxonomic classification and nomenclature

Clinical

Heritable DNA variations, associations with human pathologies, and clinical diagnostics and treatments

ClinicalTrials.gov

Privately and publicly funded clinical studies conducted around the world

ClinVar

Human variations of clinical significance

dbGaP

Genotype/phenotype interaction studies

dbSNP

Short genetic variations

dbVar

Genome structural variation studies

GTR

Genetic testing registry

MedGen

Medical genetics literature and links

OMIM

Online mendelian inheritance in man

PubChem

Repository of chemical information, molecular pathways, and tools for bioactivity screening

BioAssays

Bioactivity screening studies

Compounds

Chemical information with structures, information and links

Pathways

Molecular pathways with links to genes, proteins and chemicals

Substances

Deposited substance and chemical information

News

Research news

The Scientist AUG. 13, 2024

Study Reveals a Cell-Eat-Cell World

From normal vertebrate development to tumor cell cannibalism, cell-in-cell events occur in many different contexts across the tree of life

The Scientist AUG. 8, 2024

Researchers Bioengin-Ear Tissue Scaffolds to Human Scale

A new approach to sculpting human-like ears merges 3D printing, xenografts, and tissue engineering.

NPR News AUG. 8, 2024

Do cats experience grief? New research suggests they might

Joe Hernandez

Researchers from Oakland University surveyed hundreds of cat caregivers and found that cats exhibited behaviors associated with grief after a fellow cat or dog in the household died.

More news

Recent blog posts

NLM Musings YESTERDAY

DiscoverWHR: Centralizing NIH’s Investments in Women’s Health Research

With DiscoverWHR—a new resource from the NIH Office of Research on Women’s Health (ORWH) and NLM—users now have easy access to NIH-funded research on the important topic of women’s health research. Explore studies, grants, clinical trials, and more on topics like menopause, PCOS, and autoimmune diseases.

NIH Director's Blog NOV. 12, 2024

Advancing a Whole-Person Approach to Women’s Health Research

So many women—myself included—have benefitted from significant medical breakthroughs over the past 60 years. As a breast cancer survivor, I’ve been fortunate to have access to excellent care. And the evidence that guided that care came directly from NIH-funded research over the past five decades. From the development of the HPV vaccine to prevent cervical cancer, to the use of statins to reduce heart disease and stroke, to effective approaches to maintaining bone health after menopause—NIH research has led to numerous breakthroughs that improve the health and well-being of women and people assigned female at birth (referred to hereafter as women). However, we know that women across the country are searching for answers to improve their health. They're trying to manage flare-ups from autoimmune diseases. They're dealing with chronic pain. They're coping with postpartum depression. For these experiences and more, we still have much work to do.

NIH Director's Blog NOV. 7, 2024

Salivary Enzyme Behind Our Carb Cravings May Have Unexpectedly Ancient History

Digestion involves much more than just your stomach. The digestive process that fuels your body begins in your mouth each time you take a bite of food and chew. An enzyme in your saliva, called amylase, then starts to break down complex carbohydrates—or starches found in many fruits, vegetables, and grains—into simpler sugars to give you their sweet flavor followed by a burst of energy. Amylase is the reason we’re so good at turning starch into calories, but it isn’t the same for everyone. There’s plenty of genetic variation in the number of salivary amylase genes (AMY1) our cells carry and, therefore, in how much of this essential starch-busting enzyme people have. Studies have suggested a link between changes in amylase gene copy numbers over time and both the rise of agriculture and starch-heavy diets. Now a study in Science, supported in part by NIH, suggests that extra copies of AMY1 are not only connected to our ability to effectively digest carbs, but also may be more ancient than previously known, arising even before modern humans split from Neanderthals and long before the advent of farming.