DataMed - an open source discovery index for finding biomedical datasets by Chen, X, Gururaj, A, Ozyurt, B, Liu, R, Soysal, E, Cohen, T, Tiryaki, F, Li, Y, Zong, N, Jiang, M, Rogith, D, Salimi, M, Kim, H, Rocca-Serra, P, Gonzalez-Beltran, A, Farcas, C, Johnson, T, Margolis, R, Alter, G, Sansone, S, Fore, I, Ohno-Machado, L, Grethe, J, Xu, H