Long-term culture refers to a research area in which cells, tissues, or organoids are maintained in culture for an extended period of time, typically for several weeks or months. This approach allows researchers to study cellular processes, responses to stimuli, and disease progression over an extended period of time in a controlled environment. Long-term culture can help to model complex biological systems more accurately and provide valuable insights into developmental processes, disease mechanisms, and potential therapeutic targets. This research area is commonly used in fields such as regenerative medicine, drug discovery, and cancer research.