Objective To investigate the clinical application of three-dimensional magnetic resonance(MR)visualization in difficult laparoscopic cholecystectomy.Methods A total of 100 patients with gallstones who were admitted to the Second People's Hospital of Shantou from January 2022 to December 2023 were selected as research objects.The patients met the criteria of"difficult gallbladder"and were assigned to two groups according to random number table.The control group(n=50)were treated with routine laparoscopic cholecystectomy.In the observation group(n=50),laparoscopic cholecystectomy was assisted by MR 3D visualization model.Surgical indexes,pain within 1 day after surgery,risk of intraoperative trauma,and incidence of postoperative complications were compared between the two groups.Results Surgical indexes and recovery indexes in the observation group were superior to those in the control group(P<0.05).The visual analogue scale(VAS)score within 1 d after operation was significantly lower than that before operation in both groups,and the improvement of VAS score in the observation group was better than that in the control group(P<0.05).The incidence of gallbladder rupture(0.00%vs 10.00%)and liver margin injury(0.00%vs 8.00%)in the observation group were lower than those in the control group(P<0.05).The incidence of complications in the observation group was significantly lower than that in the control group(2.00%vs 14.00%,P<0.05).Conclusion The construction of MR 3D visualization model can provide clearer surgical field for laparoscopic cholecystectomy,and enable the operator to clarify the anatomical structure of the gallbladder,avoid surgical trauma,improve the postoperative recovery,alleviate postoperative pain,and reduce the risk of complications.

Objective To investigate the mechanism of xCT on tumor metastasis in breast cancer cell MDA-MB-231. Methods Wound scratch assay and Transwell assay were performed to evaluate the effect of disruption and knockdown of xCT on cell migration and cell invasion in breast cancer cell MDA-MB-231 .Western Blot and RT-PCR were used to detect the expression levels of autophagy and EMT related markers in breast cancer cell MDA-MB-231 after treatment with sulfasalazine (SASP), an inhibitor of xCT activity and SLC7A11-RNAi.Results Both the scratch assay and the transwell migration assay showed that inhibition of xCT reduced the motility of MDA-MB-231 .The expression level of autophagy related protein LC3-Ⅱ/LC3-Ⅰwas elevated, the protein level of transcription factor Snail was down-regulated, while the mRNA level of Snail did not change in xCT inhibited MDA-MB-231 cells compared with MDA-MB-231 cells.Epithelial marker E-cadherin was up-regulated but mesenchymal marker Vimentin was down-regulated when xCT was deficient.Con-clusion Our current studies show that xCT is an endogenous regulator of tumor growth and metastasis in MDA -MB-231 and the expression level of xCT determines the phenotypes of MDA-MB-231 cells in invasion and migration in vitro.Inhibition of xCT can activate autophagy , induce the degradation of Snail ,and attenuate the EMT process in highly metastatic MDA-MB-231 cells.