Embryo Implantation/physiology; L-Selectin/physiology; Oligosaccharides/physiology; Antibodies/pharmacology; Apoptosis/drug effects; Apoptosis/physiology; Cell Adhesion/drug effects; Cell Adhesion/genetics; Cell Adhesion/physiology; Cells, Cultured; Embryo Implantation/drug effects; Embryo Implantation/genetics; Epithelial Cells/drug effects; Epithelial Cells/metabolism; Epithelial Cells/physiology; Female; Fucosyltransferases/genetics; Fucosyltransferases/metabolism; Humans; L-Selectin/metabolism; Models, Theoretical; Oligosaccharides/antagonists & inhibitors; Oligosaccharides/immunology; Oligosaccharides/pharmacology; Sialyl Lewis X Antigen; Transfection; Trophoblasts/drug effects; Trophoblasts/metabolism; Trophoblasts/physiology; Up-Regulation/drug effects; Up-Regulation/genetics; Uterus/cytology; Uterus/metabolism; Uterus/physiology