title: Grief: its nature and significance.
mesh_terms: D000222:Adaptation, Physiological; D000223:Adaptation, Psychological; D001007:Anxiety; D003469:Culture; D004644:Emotions; D006117:Grief; D006167:Guilt; D006791:Hostility; D006801:Humans; D009042:Motivation; D010827:Physiology