OBJECTIVE：To inves tigate the application effect and safety of modified compound polyethylene glycol electrolyte powder（SF-PEG）in intestinal preparation method for patients with constipation undergoing colonoscopy. METHODS ：From Jan. 2020 to Aug. 2020，160 patients with constipation undergoing colonoscopy in anorectal department of the affiliated hospital of North Sichuan Medical College were randomly divided into observation group and control group ，with 80 cases in each group. The patients in the control group took 2 boxes of SF-PEG （mixed into 3 000 mL warm water ）orally at 3：00 a.m. on the day of examination，and finished within 2 hours. The patients in the observation group took 1 box of SF-PEG （mixed into 1 500 mL warm water）at 20：00 the night before the examination and 5：00 in the morning of the day of examination ，and drank it within 1 hour；1 bottle of Dimethylsiloxane powder （mixed into 75 mL warm water ）was taken orally at 7：00 a.m. on the inspection day. The satisfaction of intestinal preparation ，intestinal bubble score ，operation time of colonoscopy ，detection of polyps ，tolerance rate ， acceptance rate of repeating intestinal preparation of patients and incidence of adverse reactions were compared between the two groups. RESULTS ：The patients of 2 groups successfully completed bowel preparation and colonoscopy. The intestinal preparation total satisfaction rate ，intestinal bubble satisfaction rate ，polyp detection rate ，tolerance rate and repeating intestinal preparation acceptance rate of patients of observation group were significantly higher than control group （P＜0.05），while the incidence of nausea and vomiting and total incidence of adverse reactions were significantly lower than control group （P＜0.05），and the operation time of colonoscopy was significantly shorter than control group （P＜0.05）. CONCLUSIONS ：Oral administration of SF-PEG in batches combined with Dimethylsiloxane powder for bowel preparation in patients with constipation before colonoscopy have the advantages of high satisfaction with bowel preparation ，less intestinal bubbles ，short operation time ，high detection rate of polyps，high tolerance rate of patients ，high acceptance rate of repeating intestinal preparation and less adverse reactions. It is a safe and effect method for intestinal preparation.

OBJECTIVE To investigate the effects of Tongxie yaofang （TXYF） on the symptoms of rats with irritable bowel syndrome with diarrhea （IBS-D） by regulating colonic tryptophan hydroxylase 1 （TPH1）， serotonin transporter （SERT） and intestinal flora. METHODS Forty-two SD rats were randomly divided into control group （7 rats） and modeling group （35 rats）. In modeling group， rat model of IBS-D was established by intragastrical administration of 0.45 g/L senna leaf solution [10 mL/（kg·d）] combined with chronic unpredictable stimulation. Thirty-five successfully modeled rats were randomly divided into model group， pinaverium bromide group [15 mg/（kg·d）] and TXYF low-dose， medium-dose and high-dose groups [3.75、7.5、15 g/（kg·d）， calculated by crude drug]， with 7 rats in each group. Each administration group was orally administered the corresponding drug， once a day， for 10 consecutive days. The general condition and weight changes of each group of rats were compared before modeling， after modeling and before administration， after the last drug intervention； the diarrhea index and visceral sensitivity were detected， and pathological changes of colon tissue were observed after modeling and before administration， after the last drug intervention. The level and expression of 5-hydroxytryptamine （5-HT）， protein and mRNA expressions of TPH1 and SERT were determined in colon tissue. The diversity and structural changes of fecal intestinal flora of rats were analyzed. RESULTS There was no significant change in colon histopathology in each group. Compared with model group， the general condition of rats in each medication group improved. The daily body weight gain of rats was significantly increased， while diarrhea index， visceral sensitivity， the expressions of 5-HT and TPH1 in colon tissue were significantly decreased； SERT expression of colon tissue was significantly increased in TXYF medium-dose and high-dose groups （P＜0.05 or P＜0.01）. The diarrhea index， colon TPH1 protein expression and colon 5-HT protein positive rate in the TXYF low-dose group decreased while the mRNA expression of SERT increased significantly （P＜0.05）. There was a dose- dependent trend in the effect of TXYF. Compared with model group， Chao1 index and Shannon index of the rats in TXYF high- dose group were significantly decreased （P＜0.05 or P＜0.01）， the beneficial bacteria such as Firmicutes and Lactobacillus increased significantly， while the pathogenic bacteria such as Proteobacteria， Escherichia-Shigella and Rikenellaceae_RC9_gut_ group decreased significantly （P＜0.05 or P＜0.01）. CONCLUSIONS TXYF can decrease the level of 5-HT and improve intestinal flora disorder by inhibiting the expression of TPH1 and up-regulating the expression of SERT in colon tissue， thus promoting the symptoms of IBS-D rats.