Classification-Index

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Classification 2025 Summer Edition

Worldwide source of medical classification resources

Class Index

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National Institutes of Health See National Institutes of Health (U.S.)

National Institutes of Health (U.S.)

General

WA 24

History

WA 24

Specific institutes

(Form number 24 in any NLM schedule where applicable)

History

(Form number 24 in any NLM schedule where applicable)

National Security See Security Measures

Native Alaskans See Alaska Natives

Native Americans See American Indian or Alaska Native

Native Americans, Federally-Recognized See American Indian or Alaska Native

Native Hawaiian or Other Pacific Islander See Native Hawaiian or Pacific Islander

Native Hawaiian or Pacific Islander

Anthropology (General)

GN 662 - GN 671

Native Hawaiians

GN 671.H3

By region or country

GN 550 - GN 674

Health issues

WA 300

In medicine

Biography

Collective

WZ 150

Prefer classification by specialty if applicable

Individual

WZ 100

History

WZ 80.5.N2

Mental health issues

WA 305

Native Hawaiians (General)

E 184.H3

Specific topics, by topic

Native Hawaiians See Native Hawaiian or Pacific Islander

Native Peoples See Indigenous Peoples

Native-Born See Indigenous Peoples

Natively Unfolded Protein See Intrinsically Disordered Proteins

Natively Unfolded Proteins See Intrinsically Disordered Proteins

Natives See Indigenous Peoples

Natpara See Parathyroid Hormone

Natriuretic Agent See Natriuretic Agents

Natriuretic Agents QV 160

Natriuretic Effect See Natriuretic Agents

Natriuretic Effects See Natriuretic Agents

Natriuretic Factor See Natriuretic Agents

Natriuretic Factors See Natriuretic Agents

Natriuretic Hormone See Natriuretic Agents

Natriuretic Hormones See Natriuretic Agents

Natriuretic Peptides, Atrial See Atrial Natriuretic Factor

Natto Bacteria See Bacillus subtilis

Natural Attenuation, Pollution See Biodegradation, Environmental

Natural Childbirth WQ 152

Natural Family Planning See Natural Family Planning Methods

Natural Family Planning Methods WP 630

Natural Fertility See Fertility

Natural Food See Food, Organic

Natural History QH 15 - QH 45.2

Natural History of Drugs See Pharmacognosy

Natural Immunity See Immunity, Innate

Natural Increase See Population Growth

Natural Killer Cells See Killer Cells, Natural

Natural Language Processing

General (medical)

W 26.55.A7

General (non-medical)

QA 76.9.N38

Natural Law See Ethics

Natural Product See Biological Products

Natural Products See Biological Products

Natural Radiation See Background Radiation

Natural Resources Conservation See Conservation of Natural Resources

Natural Rubber See Rubber

Natural Rubber Latex Allergy See Latex Hypersensitivity

Natural Science Disciplines

General works

QH 45 - QH 45.2