Biological Characterization of a ?-Galactosidase Expressing Clone of Trypanosoma cruzi CL Strain Ana Le-Senne, Susana Muelas-Serrano, Carlos Fernández-Portillo, José Antonio Escario, Alicia Gómez-Barrio PAGE: 1101-1105

Experimental Evidence for a Demographic Cline in Panstrongylus megistus Populations Silvia E Barbosa*, Rodrigo PP Soares*, Herton HR Pires, Liléia Diotaiuti PAGE: 773-775

Characterization of Subpopulations (Clones and Subclones) of the 21 SF Strain of Trypanosoma cruzi after Long Lastin Rozalia MF Campos, Sonia G Andrade PAGE: 795-800

Biological Characterization of Clones Derived from the Edmonston Strain of Measles Virus in Comparison with Schwarz and CAM-70 Vaccine Strains Maria Beatriz Junqueira Borges, George F Mann, Marcos da Silva Freire PAGE: 507-514

Biological Comparison between Three Clones of Trypanosoma cruzi and the Strain of Origin (Bolivia) with Reference to Clonal Evolution Studies P Penin, C Gamallo, JA de Diego PAGE: 285-291