Objective:To explore the technical advantages of MR cholangiopancreatography (MRCP) with single breath holding high parallel acquisition factor 3-D variable flip angle fast spin echo (3D-SPACE) sequence.Methods:From November 2018 to March 2019, 75 patients who underwent MRCP examination in our hospital were prospectively enrolled, with single breath holding high parallel acquisition factor 3D-SPACE sequence and free breathing navigation gated 3D-SPACE sequence. Three experienced radiologists scored the overall image quality, artifacts, CBD visibility, left and right hepatic ducts, right anterior and posterior branches, second and third branches, main pancreatic duct and gallbladder duct with four scales. Paired t test was used for statistical analysis. Results:The scanning time of single breath holding method (18 s) was significantly shorter than that of free breathing diaphragm navigation method［264（226，313）s］, and the difference between the two methods was statistically significant ( Z=-7.520， P<0.001). The SNR, CR and CNR (8.31±4.23, 0.92±0.30, 11.46±5.77) of single breath holding method were lower than those of free breathing diaphragm navigation method (11.23±5.70, 0.93±0.38, 15.06±7.37), and the differences between the two methods were also statistically significant ( t=4.378, 3.429, 4.063, P<0.05). The overall image quality, artifact, the CBD, left and right hepatic duct, right anterior and posterior branchs, the second and third branches, main pancreatic duct and cystic duct of single breath holding method were higher than those of free breathing diaphragm navigation method, and the differences between the two methods were statistically significant ( P<0.001). Conclusions:Compared with the free breathing diaphragm navigation gated 3D-SPACE MRCP imaging method, the single breath holding high parallel acquisition factor 3D-SPACE MRCP imaging method has less artifacts and examination time, but higher visibility to pancreaticobiliary tree and work efficiency, which is worthy of further promotion.

Objective To evaluate the protective effect of epigallocatechin-3-gallate(EGCG)on cisplatin(CIS)-induced acute kidney injury(AKI)in rats based on network pharmacology and in vivo animal model experiments.Methods Targets of EGCG and AKI were collected from the TCMSP,Gene Cards,and OMIM websites,and a protein-protein interaction network was constructed based on the intersection.The intersection targets were analyzed visually using Cytoscape 3.9.1 and the key targets were screened out.Kyoto Encyclopedia and of Genes and Genomes and Gene Ontology enrichment analyses were carried out using the DAVID database.Thirty-two male Wistar rats were divided randomly into four groups:CON group,EGCG group,CIS group,and CIS+EGCG group.Rats in the control and CIS groups were given normal saline every day,rats in the EGCG and CIS+EGCG groups were given EGCG(40 mg/kg)every day for 28 d,and rats in the CIS and CIS+EGCG groups received an intraperitoneal injection of CIS(7 mg/kg)on the 26th day.Blood and tissue samples were obtained on the 29th day.Serum urea nitrogen and creatinine levels were detected,renal pathology was observed by HE staining,and apoptosis in renal tissue was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling.Western Blot,qRT-PCR,and immunohistochemistry were used to verify the result.Results Eighty-seven genes intersecting EGCG and AKI and 25 core targets were screened from network pharmacology,which influenced the development of AKI via signal pathways such as PI3K/Akt and various biological processes.EGCG pretreatment significantly reduced serum levels of serum urea nitrogen and creatinine,improved the renal pathology,and reduced renal tissue apoptosis in AKI rats.Western Blot,qRT-PCR and immunohistochemistry showed that pretreatment with EGCG activated the PI3K/Akt pathway.Conclusions EGCG alleviates CIS-induced AKI in rats via the PI3K/Akt signaling pathway.