Trachea to prevent swallowed matter from entering the trachea. In the fourth week of development of the human embryo as the respiratory bud grows, the trachea separates from the foregut through the formation of tracheoesophageal ridges which fuse to form the tracheoesophageal septum and this separates the future trachea from the oesophagus and divides the foregut tube into the laryngotracheal tube. Before the end of the fifth week, the trachea begins to develop from the laryngotracheal tube which develops from the laryngotracheal groove. The first part of the cephalic region of the tube forms the larynx, and the next part forms
Traditional Chinese medicines derived from the human body centuries after Li Shizhen considered the bioethical and biomedical dilemmas of using human drugs, 20th-century technological and medical advances have raised new related questions of organ transplants, transplantation medicine, organ trade, tissue banks, human cloning, and the commodification of human body parts (Awaya 1999, Nie 2002, Scheper-Hughes and Wacquant 2002). Traditional Chinese medicines derived from the human body Li Shizhen's (1597) "Bencao gangmu", the classic materia medica of traditional Chinese medicine (TCM), included 35 human drugs, including organs, bodily fluids, and excreta. Crude drugs derived from the human body were commonplace in the early history of medicine. Some of these