We've learned two pathogen-removing herbs that can be used for both food and medicine. Now let's move on. First, I'd like to talk about another one for both food and medicine: Sang Ye (Folium Mori). Actually Sang (the mulberry) is a real treasure. Its leaves are called Sang Ye, its root bark is called Sang Bai Pi (Cortex Mori), it twig is called Sang Zhi (Ramulus Mori), and its fruit is called Sang Shen (Fructus Mori). All these are of great medicinal value. Here we'll mainly introduce Sang Ye. In Chinese medicine, Sang Ye falls under the category of wind-removing and heat-clearing type. In this sense, it can undoubtedly release the exterior. However, it is not pungent, but sweet and bitter in flavor, and cold in property. We know that sweet and cold moisten, and bitter and cold clear. That's why it was classified as a exterior-releasing herb. I'd like to summarize the functions of Sang Ye into four words: dispersing, dissipating, clearing and moistening. It is mainly used to treat problems of the lung and liver. First, let's take a look at its function on the lung. It can be used to treat the lung in two aspects. First, since it can remove wind and clear heat, it shares similar function with Niu Bang Zi (Fructus Arctii) we have learned in the tretment of common cold due to wind cold and early stage of febrile diseases. I'd like to clarify that Sang Ye can release the exterior although the effect in this regard is not so strong. This is the first aspect. The second aspect in the treatment of lung problems is to stop coughing. This is one of its major functions: it has good effect in stopping cough. Even when it's used to clear heat and dispel wind, it's used more when patients also experience cough. Speaking of which, it's almost a specific herb for cough through multiple means. First, it can dispel wind and clear heat and can therefore disperse the lung and stop coughing in externally contracted conditions, including cough due to common cold. Sang Ye can be used for all kinds of cough in an exterior syndrome, such as wind cold, wind-heat or autumn dryness. Of course it's best indicated for cough in common cold related to heat or dryness. The second aspect: since it is bitter in flavor and cold in property, it can clear heat. In addition, it enters the lung meridian and can therefore be used to clear lung heat and stop coughing, i.e., it's indicated for cough due to lung heat, For exampke, cough with phlegm, yellow sticky phlegm can be treated with Sang Ye. The third aspect: it is sweet and cold and can therefore moisten. What does it moisten? It enters the lung meridian and can therefore moisten the lung and stop coughing. Moist is opposite to dryness. Cough here often refers to unproductive cough. The characteristics of Sang Ye in treating unproductive cough is that it can be used to treat external dryness, such as dry cough in autumn or unproductive cough due to lung yin deficiency. It can also moisten the lung and stop coughing. Consequently Sang Ye has remarkable effect on cough. It is frequently used to stop coughing because it can disperse, clear and moisten the lung. Additionally, you can use a large dose from 15 g to 30 g. This is its first function on the lung, manifesting as releasing the exterior and stopping cough. The second major application of Sang Ye is for the liver. This also manifests in two aspects. One is that it soothes liver yang. Since it soothes liver yang, it can be used to treat hyperactivity of liver yang. Sang Ye is effective for headache and vertigo due to hyperactivity of liver yang. Its second function on the liver is to improve the eyesight. Compared with soothing liver yang, it's more often used to benefit eyes. We know that in Chinese medicine, eyes are associated with the liver since the liver opens into the eyes. Ascending of liver fire may cause redness, swelling and pain of the eyes. In this case, we need to clear liver fire. Sang Ye enters the liver meridian and it is also bitter in flavor and cold in property, so it can clear liver fire and benefit the eyes. The second aspect: when we say 'the liver opens into the eyes', we also mean liver blood or liver yin nourishes the eyes. Deficiency of liver blood or liver yin may cause malnourishment of the eyes, leading to deficiency eye problems, such as blurred vision, cataract, senile cataract. We've mentioned that Sang Ye is sweet and cold and enters the liver meridian, so it can nourish liver yin and benefit the eyes. It can therefore be used to treat deficient eye conditions due to liver yin deficiency. So in summary, for liver problems, Sang Ye can soothe the liver and can be used to treat vertigo due to hyperactivity of liver yang; it benefits the eyes and can be used for eye problems in either excess or deficiency syndrome. Generally speaking, Sang Ye has no adverse reactions. We can use a large dose betwen 10 and 30 g. So much for Sang Ye. Next, I'd like to talk about another pathogen-removing herb that can be used for both food and medicine Bai Zhi (Radix Angelicae Dahuricae). This herb also falls under the category of cold-dissipating and wind-removing herbs. Actually it's of great value in our daily life. For example, when preserving snake in wine, you can use Bai Zhi to remove turbidity and abnormal odor. In addition, around the dragon boat festival, many people wear a sachet, which contains fragrant herbs, including Bai Zhi. Zhi means the root of grass. So we make sachets using Bai Zhi and Ai Ye (mugwort leaf) and wear them for disease prevention and treatment. This is how we use Bai Zhi in our life. We've mentioned Bai Zhi can remove wind and dissipate cold. In terms of property, it is fragrant, pungnet and warm, and mainly acts on the lung and stomach. I'd like to summarize the application of Bai Zhi into two aspects. From its flavor, it is fragrant. From its application, Bai Zhi is extensively used in clinical practice. It can be used in all clinical subspecialties, including internal medicine, external medicine, pediatrics, ENT and dermatology. Let's take a look. First, since it can remove wind and dissipate cold, it can release the exterior, which is called remove wind and release the exterior. Actually its effect in dissipating cold and removing wind is not very strong but it can also release the exterior. What's the characteristic? Other than releasing the exterior, it is fragrant, ascending and dispersing, and therefore it can open noses and at the same time, alleviate pain. As a result, it's not commonly used for wind-cold exterior syndrome. However, it is very effective for wind-cold exterior syndrome coupled with nasal obstruction and headache. So when we say it can release the exterior, it's mainly used for headache and nasal obstruction due to wind-cold exterior syndrome. This is its second function. I've mentioned that it opens the noses. We say Bai Zhi is mainly used for nasal problems. We can also say, Bai Zhi is a special herb for nasal problems, such as nasal bleeding or nasal obstruction. In modern medicine, Bai Zhi can be used for allergic rhinitis, nasal sinusitis and accessory sinusitis. In other words, it's specially used for nasal problems. This is the second aspect. Thirdly, we've mentioned Bai Zhi has very good pain-relief effect. But it mainly dissipates cold and alleviates pain. Therefore it's mainly used for cold pain, especially cold pain in the head and face. We've mentioned pain like frontal headache, supra-orbital pain, toothache can all be treated with Bai Zhi. In addition, it can be used for rheumatic joint pain (related to wind and dampness in Chinese medicine). This is its third function. We've mentioned that Bai Zhi can be used to treat common cold or pain that are mainly associated with internal medicine and pediatrics. Also, it's a special herb for nasal problems that are related to ENT. Its next function is about gynecological conditions. It can dry dampness and relieve leucorrhea. In Chinese medicine, leucorrhea is one of the major four gynecological conditions... menstruation, leucorrhea, pregnancy and childbirth. In Chinese medicine, leucorrhea is caused by dampness, i.e., dampness is the main contributing factor of leucorrhea. To treat leucorrhea, you need to resolve dampness. How? The most direct and effective method is to dry dampness. Bai Zhi is fragrant, warm and dry and can dry dampness and stop leucorrhea. So it can be mainly used in gynecological department for leucorrhea. Its last function is about the external and dermatological conditions, because it can resolve swelling and drain pus in sores or ulcers. In Chinese medicine, sores or ulcers are often classified into initial, middle and late stages. During the initial stage, patients often present with local redness, swelling and burning pain. We can use Bai Zhi to resolve swelling and alleviate pain. We can also combine with herbs that can clear heat and remove toxins. During the middle stage when pus has been formed, the treatment principle is to drain the pus and remove toxins. Bai Zhi can help to drain pus. In this stage, we can combine with herbs that can clear heat, remove toxins, circulate blood and resolve stasis. Bai Zhi cannot help with wound healing in the late stage. So Bai Zhi is used to resolve swelling and drain pus during initial and middle stages of sores or ulcers. It can be seen that Bai Zhi can be used in internal medicine, pediatrics, gynecology, ENT, external medicine and dermatology. Consequently, Bai Zhi has extensive use in clinical practice. In this class, I've mainly introduced two herbs: one is Sang Ye for the liver and lung; and other is Bai Zhi for extensive clincal application. So much for this class.