chronic stress Animals 8 Stress, Psychological 8 Female 6 T lymphocyte 6 animal experiment 6 article 6 controlled study 6 nonhuman 6 priority journal 6 Behavior, Animal 4 CD4-Positive T-Lymphocytes 4 CD4/CD8 4 Cell Proliferation 4 Chronic Disease 4 Chronic stress 4 Cytokines 4 Interferon-gamma 4 Killer Cells, Natural 4 Mice 4 Mice, Inbred BALB C 4 Restraint, Physical 4 T-Lymphocytes 4 Tumor Necrosis Factor-alpha 4 animal cell 4 animal model 4 cellular immunity 4 female 4 gamma interferon 4 glucocorticoid 4