| #281 | Proceedings of the National Academy of Sciences of the United States of America. -- Washington : National Academy of Sciences, 1914-. -- ISSN 0027-8424 print. -- ISSN 1091-6490 online |
| #282 | Proceedings of the National Science Council, Republic of China, Part B, Life sciences. -- Taipei : National Science Council, 1984-2001. -- ISSN 0255-6596 |
| #283 | Proceedings of the Royal College of Physicians of Edinburgh. -- Edinburgh : Royal College of Physicians of Edinburgh, 1986-2001. -- ISSN 0953-0932 |
| #284 | Proceedings of the Royal Society of Medicine. -- London : Royal Society of Medicine Press, 1907-1977. -- ISSN 0035-9157 |
| #285 | Proceedings of the Society for Experimental Biology and Medicine. -- Malden : Blackwell Science, 1904-2000. -- ISSN 0037-9727 |
| #286 | Profi medicína : odborné fórum pracovníků ve zdravotnictví. -- Praha : A 11 s.r.o., 2019-. -- ISSN 2571-252 |
| #287 | Progress in clinical and biological research. -- New York : Wiley-Liss, 1975-1998. -- ISSN 0361-7742 |
| #288 | Przegląd Lekarski. -- Kraków : Przeglad lekarski, 1945-. -- ISSN 0033-2240 |
| #289 | Pulsus. -- Bratislava : Schneider Group, 1992-1994. -- ISSN 1210-3136 |
| #290 | Pulsus Plus. -- Bratislava : Vista Group, 1994-1995. -- ISSN 1335-0870 |