Ekspresi IGF-I, IGFBP-1, Leptin, dan Reseptor Leptin Pada Plasenta Ibu Hamil yang Terinfeksi Plasmodium falciparum di Timika, Papua = Expression of IGF-I, IGFBP-1, Leptin, and Leptin Receptors in the placentae of Plasmodium falciparum-infected pregnant women in Timika, Papua