The thoroughfare vessel is one of eight extra meridians and named sea of viscera, sea of blood and sea of twelve meridians. The thoroughfare vessel is closely related to qi and blood and has important guiding significance for clinical practice. Analysis of literature about the thoroughfare vessel finds that the literature of past dynasties has different descriptions of the initial site of the thoroughfare vessel. Qichong, infrarenal, Guanyuan and uterus were considered as its initial site. By summarizing the related statements of past dynasties, this article analyzes different initial sites of the thoroughfare vessel and considers that infrarenal uterus is the initial site of the thoroughfare vessel. That not only enriches and develops the physiological and pathological theories of the thoroughfare vessel and endows the thoroughfare vessel with more extensive contents but also provides more clinical guidance.

Umbilical needling therapy of I-Ching is a new kind of acupuncture therapy conducted by Professor Qi Yong, based on and the comprehension of Zhou Yi, and enormous clinical experiences. It has now been accepted and usedgradually. Umbilical needling treatments of various diseases are with obvious effect. There are few clinical studies on the application of this therapy alone, and it is more combined with other therapies such as acupuncture, moxibustion and Traditional Chinese Medicine (TCM) for the purpose of healing. A wide range of diseases could be traeated by the combination of umbilical needling therapy and acupuncture. Umbilical needling therapy combined with moxibustion is often used to treat gynecological diseases. Internal diseases could be traeated by the combination of umbilical needling therapy and TCM. The umbilical needling therapy still lacks of systematic research and uniformed curative effect standard, and there are some difficulties and risks in practice. Therefore, its development has limitations. Besides, there are few studies on the "preventive treatment of disease" . The future research should base on the original theory, overcome the operational difficulties and carry out systematic research.