Circulating angiogenic factors and HIV among pregnant women in Zambia: a nested case–control study oleh Megan E. Smithmyer, Chileshe M. Mabula-Bwalya, Humphrey Mwape, Gabriel Chipili, Bridget M. Spelke, Margaret P. Kasaro, Kristina De Paris, Bellington Vwalika, Yuri V. Sebastião, Jeffrey S.A. Stringer, Joan T. Price