Obesity and Metabolism

English
ISSN: 1825-3865
EISSN: 1826-7572
FREE
2005 - present

Non-printable PDFs are available to non-subscribers, printable PDFs are reserved to subscribers. A free registration on the journal's website must be completed, before accessing documents.

Obesity Research

English
ISSN: 1071-7323
EISSN: 1550-8528
FREE
2000 - 2005

Title has changed, since 2006, to 'Obesity'.

Obstetrician and Gynaecologist, [The]

English
ISSN: 1467-2561
EISSN: 1744-4667
Free after 24 months
1999 - present

Obstetrics and Gynecology

English
ISSN: 0029-7844
EISSN: 1873-233X
Free after 12 months
1999 - present

Not all articles are freely available.

Obstetrics and Gynecology International

English
ISSN: 1687-9589
EISSN: 1687-9597
FREE
2009 - present

Obstetrics and Gynecology Science

English
ISSN: 2287-8572
EISSN: 2287-8580
FREE
2013 - present

Title was 'Korean Journal of Obstetrics and Gynecology' until 2012.

Occasional Papers: Royal College of General Practitioners

English
ISSN: 1352-2450
FREE
1988 - 2006

Occupational and Environmental Medicine

English
ISSN: 1351-0711
EISSN: 1470-7926
FREE
1994 - 2006

Continues 'British Journal of Industrial Medicine'. Free access to all articles prior to 2006. A one-time registration needs to be completed to access the archive, here: http://journals.bmj.com/cgi/register

Occupational Medicine

English
ISSN: 0962-7480
EISSN: 1471-8405
Free after 12 months
1996 - present

Ochsner Journal, [The]

English
ISSN: 1524-5012
FREE
2002 - present

Ocular Oncology and Pathology

English
ISSN: 2296-4681
EISSN: 2296-4657
FREE
2014 - present

Odonto

English Portuguese
ISSN: 1518-7004
EISSN: 2176-1000
FREE
2007 - present

Odontoestomatología

ISSN: 1688-9339
FREE
2009 - present

Odontología Pediátrica

ISSN: 1814-487X
FREE
2004 - 2012

Odontos

ISSN: 1659-1046
EISSN: 2215-3411
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2004 - 2011

Okajimas Folia Anatomica Japonica

English
ISSN: 0030-154X
EISSN: 1881-1736
FREE
1936 - present

Title was 'Folia Anatomica Japonica' until 1935.

Oman Journal of Ophthalmology

English
ISSN: 0974-620X
EISSN: 0974-7842
FREE
2008 - present

Oman Medical Journal

English
ISSN: 1999-768X
EISSN: 2070-5204
FREE
2007 - present

Oncogene

English
ISSN: 0950-9232
EISSN: 1476-5594
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1997 - 2009

Oncogenesis

English
EISSN: 2157-9024
FREE
2012 - present

Oncología

ISSN: 0378-4835
FREE
2004 - 2007

Ceased publication in 2007.

Oncologist, [The]

English
ISSN: 1083-7159
EISSN: 1549-490X
Free after 12 months
1996 - present

Oncology Reports

English
ISSN: 1021-335X
EISSN: 1791-2431
Free after 12 months
2006 - present

Oncoscience

English
EISSN: 2331-4737
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2014 - present

Oncotarget

English
EISSN: 1949-2553
FREE
2010 - present

OncoTargets and Therapy

English
EISSN: 1178-6930
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2008 - present

Onderstepoort Journal of Veterinary Research

English
ISSN: 0030-2465
EISSN: 2219-0635
FREE
2004 - present

Onkologia w Praktice Klinicznej

ISSN: 1734-3542
FREE
2005 - present

Only in the Polish version of the website it is possible to download the fulltext of the documents.

Onkologische Welt, [Der]

German
ISSN: 1869-0874
FREE
2010 - 2012

Preceeded by 'Internistische Welt: Onkologie, [Der]'.

Online Brazilian Journal of Nursing

English Portuguese
ISSN: 1676-4285
FREE
2005 - present

Online Journal of Biological Sciences

English
ISSN: 1608-4217
FREE
2006 - present

Online Journal of Health and Applied Sciences

English
ISSN: 0972-5997
FREE
2002 - present

Online Journal of Health Ethics

English
ISSN: 1551-4218
FREE
2004 - present

Online Journal of Issues in Nursing

English
EISSN: 1091-3734
FREE
1996 - present

Online Journal of Public Health Informatics

English
ISSN: 1947-2579
FREE
2009 - present

Online Journal of Rural Nursing and Health Care

English
ISSN: 1539-3399
FREE
2000 - present

Ontario Health Technology Assessment Series

English
EISSN: 1915-7398
FREE
2001 - present

Open Access Animal Physiology

English
ISSN: 1179-2779
FREE
2009 - present

Open Access Emergency Medicine

English
EISSN: 1179-1500
FREE
2009 - present

Open Access Journal of Clinical Trials

English
EISSN: 1179-1519
FREE
2009 - present

Open Access Journal of Medicinal and Aromatic Plants

English
ISSN: 0974-7877
FREE
2010 - present

Open Access Journal of Sports Medicine

English
EISSN: 1179-1543
FREE
2010 - present

Open Access Journal of Urology

English
EISSN: 1179-1551
FREE
2009 - 2011

Title changed to 'Research and Reports in Urology' since 2012.

Open Access Rheumatology: Research and Reviews

English
EISSN: 1179-156X
FREE
2009 - present

Open Access Surgery

English
EISSN: 1178-7082
FREE
2008 - present

Open AIDS Journal

English
EISSN: 1874-6136
FREE
2007 - present

Open Allergy Journal

English
ISSN: 1874-8384
FREE
2008 - present

Open Anesthesiology Journal

English
ISSN: 1874-3218
FREE
2007 - present

Open Autoimmunity Journal

English
ISSN: 1876-8946
FREE
2009 - present

Open Bioactive Compounds Journal

English
ISSN: 1874-8473
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2008 - present

Open Biochemistry Journal

English
EISSN: 1874-091X
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2007 - present

Open Biology

English
EISSN: 2046-2441
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2011 - present

Open Biomarkers Journal

English
ISSN: 1875-3183
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2008 - present

Open Biomedical Engineering Journal

English
EISSN: 1874-1207
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2007 - present

Open Biotechnology Journal

English
ISSN: 1874-0707
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2007 - present

Open Cancer Immunology Journal

English
ISSN: 1876-4010
FREE
2010 - present

Open Cancer Journal

English
ISSN: 1874-0790
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2007 - present

Open Cardiovascular Medicine Journal

English
EISSN: 1874-1924
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2007 - present

Open Clinical Cancer Journal

English
ISSN: 1874-1894
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2007 - present

Open Dentistry Journal

English
EISSN: 1874-2106
FREE
2007 - present

Open Dermatology Journal

English
ISSN: 1874-3722
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2007 - present

Open Diabetes Journal

English
ISSN: 1876-5246
FREE
2009 - present

Open Drug Metabolism Journal

English
ISSN: 1874-0731
FREE
2009 - present

Open Forum Infectious Diseases

English
EISSN: 2328-8957
FREE
2014 - present

Open Gene Therapy Journal

English
ISSN: 1875-0370
FREE
2008 - present

Open Genomics Journal

English
ISSN: 1875-693X
FREE
2008 - present

Open Health Data

English
EISSN: 2054-7102
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2013 - present

Open Heart

English
EISSN: 2053-3624
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2014 - present

Open Hematology Journal

English
ISSN: 1874-2769
FREE
2007 - present

Open Immunology Journal

English
ISSN: 1874-2262
FREE
2008 - present

Open Infectious Diseases Journal

English
ISSN: 1874-2793
FREE
2007 - present

Open Journal of Cardiovascular Surgery

English
EISSN: 1179-0652
FREE
2008 - present

Open Journal of Occupational Therapy

English
ISSN: 2168-6408
FREE
2012 - present

Open Medical Devices Journal

English
ISSN: 1875-1814
FREE
2009 - present

Open Medical Informatics Journal

English
EISSN: 1874-4311
FREE
2007 - present

Open Medicinal Chemistry Journal

English
EISSN: 1874-1045
FREE
2007 - present

Open Medicine

English
EISSN: 1911-2092
FREE
2007 - present

Open Medicine

English
EISSN: 2391-5463
FREE
2015 - present

Title was 'Central European Journal of Medicine' until 2014.

Open Microbiology Journal

English
EISSN: 1874-2854
FREE
2007 - present

Open Neuroimaging Journal

English
EISSN: 1874-4400
FREE
2007 - present

Open Neurology Journal

English
EISSN: 1874-205X
FREE
2007 - present

Open Neuropsychopharmacology Journal

English
ISSN: 1876-5238
FREE
2009 - present

Open Neuroscience Journal

English
ISSN: 1874-0820
FREE
2007 - present

Open Nursing Journal

English
EISSN: 1874-4346
FREE
2007 - present

Open Pain Journal

English
ISSN: 1876-3863
FREE
2009 - present

Open Pharmacology Journal

English
ISSN: 1874-1436
FREE
2007 - present

Open Proteomics Journal

English
ISSN: 1875-0397
FREE
2008 - present

Open Respiratory Medicine Journal

English
EISSN: 1874-3064
FREE
2007 - present

Open Rheumatology Journal

English
EISSN: 1874-3129
FREE
2007 - present

Open Spine Journal

English
ISSN: 1876-5327
FREE
2009 - present

Open Surgical Oncology Journal

English
ISSN: 1876-5041
FREE
2009 - present

Open Tissue Engineering and Regenerative Medicine Journal

English
ISSN: 1875-0435
FREE
2008 - present

Open Toxicology Journal

English
ISSN: 1874-3404
FREE
2007 - present

Open Tropical Medicine Journal

English
ISSN: 1874-3153
FREE
2008 - present

Open Vaccine Journal

English
ISSN: 1875-0354
FREE
2008 - present

Open Veterinary Journal

English
ISSN: 2226-4485
EISSN: 2218-6050
FREE
2011 - present

Open Virology Journal

English
EISSN: 1874-3579
FREE
2007 - present

Open Women's Health Journal

English
ISSN: 1874-2912
FREE
2007 - present

Operative Techniques in Cardiac and Thoracic Surgery

English
ISSN: 1085-5637
FREE
1996 - 1998

Title changed to 'Operative Techniques in Thoracic and Cardiovascular Surgery' in 1998.

Operative Techniques in Cardiac and Thoracic Surgery

English
ISSN: 1085-5637
FREE
1996 - 1998

Title changed, since 1999, to 'Operative Techniques in Thoracic and Cardiovascular Surgery'. Articles 1996-1998 are free.

Operative Techniques in Thoracic and Cardiovascular Surgery

English
ISSN: 1522-2942
Free after 24 months
1998 - present

Title was 'Operative Techniques in Cardiac and Thoracic Surgery' until 1998.

Ophthalmology and Eye Diseases

English
ISSN: 1179-1721
FREE
2009 - present

Ophthalmology and Therapy

English
ISSN: 2193-8245
EISSN: 2193-6528
FREE
2012 - present

Optics Express

English
EISSN: 1094-4087
FREE
1997 - present

Optometry and Vision Science

English
ISSN: 1040-5488
EISSN: 1538-9235
Free after 12 months
1989 - present

ORAL & Implantology (Odontostomatology Research Anatomy Learning and Implantology)

English
ISSN: 1974-5648
EISSN: 2035-2468
FREE
2008 - present

This is an open access journal. A free registration, however, must be done to see fulltext articles.

Oral Oncology Extra

English
ISSN: 1741-9409
FREE
2004 - 2006

Ceased publication in 2007.

Oral Sciences

Portuguese
ISSN: 1808-8821
FREE
2005 - 2012

Organic and Medical Chemistry Letters

English
EISSN: 2191-2858
FREE
2011 - present

Organogenesis

English
ISSN: 1547-6278
EISSN: 1555-8592
Free after 12 months
2004 - present

Oriental Pharmacy and Experimental Medicine

English
ISSN: 1598-2386
EISSN: 2211-1069
FREE
2001 - 2010

Orphanet Journal of Rare Diseases

English
EISSN: 1750-1172
FREE
2006 - present

Orthopaedic Journal of Sports Medicine

English
EISSN: 2325-9671
FREE
2013 - present

Orthopedics and Traumatology: Surgery and Research

English
EISSN: 1877-0568
FREE
2009 - present

This journal is open access. However, a free registration must be completed in order to access the articles.

Ortodoncia Clínica

ISSN: 1139-4714
FREE
2000 - 2009

This journal is open access. However, a free registration must be completed in order to access the articles.

Ortopedia Traumatologia Rehabilitacja

English
ISSN: 1509-3492
FREE
2005 - present

Osetrovatelství a Porodní Asistence

ISSN: 1804-2740
FREE
2010 - 2013

Title changed to 'Central European Journal of Nursing and Midwifery' since 2014.

Osteologie

German
ISSN: 1019-1291
FREE
2002 - 2007

Osteopathic Medicine and Primary Care

English
EISSN: 1750-4732
FREE
2007 - 2010

Osteopatía Científica

ISSN: 1886-9297
Free after 24 months
2008 - 2011

Ostomy Wound Management

English
ISSN: 0889-5899
EISSN: 1943-2720
FREE
2001 - present

Only HTML version is free without registration. A free registration is needed to access PDF version of the documents.

Oxford Medical Case Reports

English
EISSN: 2053-8855
FREE
2014 - present

Oxidative Medicine and Cellular Longevity

English
ISSN: 1942-0900
EISSN: 1942-0994
FREE
2008 - present