Bone Marrow Cells/physiology; Cytokines/pharmacology; Glioma/therapy; Stromal Cells/physiology; Animals; Antigens, CD/metabolism; Blotting, Northern/methods; Blotting, Southern/methods; Bone Marrow Cells/drug effects; Cell Count/methods; Cell Survival/physiology; Cells, Cultured; Coculture Techniques/methods; Culture Media, Conditioned/metabolism; Cytokines/metabolism; Drug Combinations; Enzyme-Linked Immunosorbent Assay/methods; Fas Ligand Protein; Flow Cytometry/methods; Gene Expression/drug effects; Gene Expression/physiology; Green Fluorescent Proteins/metabolism; In Situ Nick-End Labeling/methods; Interleukin-4/metabolism; Male; Membrane Glycoproteins/genetics; Membrane Glycoproteins/metabolism; RNA, Messenger/biosynthesis; Rats; Rats, Sprague-Dawley; Reverse Transcriptase Polymerase Chain Reaction/methods; Transfection/methods; Tumor Necrosis Factors/genetics; Tumor Necrosis Factors/metabolism