Trachea into left and right main bronchi. The trachea begins level with the sixth cervical vertebra and the carina is found at the level of the fifth thoracic vertebra (T5), opposite the sternal angle and can be positioned up to two vertebrae lower or higher, depending on breathing. The trachea is surrounded by rings of hyaline cartilage; these rings are incomplete and C-shaped. The cricoid cartilage is attached to the first tracheal ring at top of the trachea and acts as the bottom of the larynx. There are fifteen to twenty rings in total, separated by narrow intervals. These reinforce the
Traditional Chinese medicines derived from the human body being are no more used medically, it seems rude to list them as drugs." Note the medical terms "dystocia" "A slow or difficult labor or delivery" and "stranguria" (i.e., "strangury" "A painful, frequent need to urinate, when the bladder is largely empty or with little urine production"). Reflecting the well-known Confucianist inhibition against mutilating one's body (Cooper & Sivin 1973: 212), Li Shizhen's preface to chapter 52 ethically condemns the use of some human drugs. The human is a different species from all the other organisms used as sources of drugs. In later times, Taoist alchemists [方伎之士] considered that many