Detection of intestinal flora can be done by means of stool culture tests. Usually, new human stool is placed in a special bacterial culture medium for bacterial culture, and the bacteria obtained from the culture can be used to know the types of bacteria and the specific number of each type of bacteria. Under normal circumstances, the types of bacteria in the human intestine are relatively fixed, and the ratio of the number of bacteria among the various types is also relatively fixed. The bacteria in each ratio interact with each other to maintain the normal flora environment of the human intestine and ensure the normal function of the intestine. If the ratio of bacterial species or the number of bacteria is detected to be out of balance, the overgrowth of certain pathogenic bacteria will affect the normal function of the intestine and lead to diarrhea and other symptoms, which can be regulated by taking probiotics.