PubMed Central® (PMC) is a free full-text archive of biomedical and life sciences journal literature at the U.S. National Institutes of Health's National Library of Medicine (NIH/NLM).
BMC Public Health is an open access, peer-reviewed journal that considers articles on the epidemiology of disease and the understanding of all aspects of public health.
PLOS Medicine gives the highest priority to papers on the conditions and risk factors that cause the greatest losses in years of healthy life worldwide.
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eMedicineeMedicine is an open access comprehensive medical textbook with over 6500 articles, and 10,000 contributors. The eMedicine point-of-care clinical reference features up-to-date, searchable, peer-reviewed medical articles organized in specialty-focused textbooks.