Objective To observe imaging characteristics and changes of vivo two-dimension multi-voxel proton magnetic resonance spectroscopy (~1H-MRS) in the rabbit models of VX2 hepatic carcinoma after high intensity focused ultrasound (HIFU) treatment. Methods VX2 hepatic carcinoma models were established in 20 New Zealand rabbits. Routine MR and 2-dimentional ~1H-MRS scanning were performed before and after HIFU treatment. The central regions of interest (ROI) of the VX2 tumor, tumor border and paratumor normal liver tissues were selected. The Cho/Cr and Lip/Cr of the same ROI before and after HIFU treatment were compared. Results Total 28 satisfied spectrogram diagram of ~1H-MRS were brought into statistical analysis. Of all the spectra, 6 metabolite peaks were detected as lipids (Lip), glutamine and glutamate complex (Glx), choline (Cho), lactate (Lac) and creatine (Cr). Cho and Lac peak in tumor center and tumor border regions after HIFU treatment were higher than those before HIFU treatment. Lip peak was lower than before, and major metabolites of paratumor normal liver tissues did not changed significantly. Statistical differences of Cho/Cr and Lipid/Cr of tumor center and border region were found between before and after HIFU treatment (P＜0.05). Conclusion Two-dimension multi-voxel ~1H-MRS can reflect major changes in the level of metabolites of different ROI for hepatic VX2 carcinoma after HIFU treatment.

Objective To assess the clinical significance of endoscopic ultrasonography (EUS) in the diagnosis and preoperative staging of gastric cancer. Methods EUS was carried out in 22 patients inclu-ding 17 gastric cancer patients and 5 patients in suspicion. Helical CT scanning was performed in all of the patients and fine needle aspiration biopsies ( FNAB) were administrated to 5 suspicious patients. Compared the results of operation and pathology with those of tumor staging by estimating the depth of tumor invasion ( T) , local lymph node metastasis ( N) and metastasis to neighboring or remote organs ( M) in order to esti-mate the accuracy of diagnosis and TNM staging. The sensitivity and specificity of tumor-node-metastasis staging of gastric cancer by EUS were compared with those of the spiral CT according to the final histopatho-logical results. Results In 5 suspicious patients specimens were successfully obtained by FNAB under the guide of EUS with the pathological diagnosis of adenocarcinoma in 4 cases and signet ring cell carcinoma, 1 case. All patients underwent radical gastrectomy except one in T1N0M0, staging was treated by endoscopic mucosal resection (EMR). The sensitivity and specificity of EUS in T, N, and M stage were 84.9% and 74. 2% , 92. 1% and 77. 1% , 63. 4% and 87. 5% respectively; whereas those of CT in T, N, and M stage were 27. 3% and 75% , 31.5% and 100% , 50% and 100% respectively. The sensitivity of EUS in T and N staging were higher than those of CT with significant statistical difference (P

Objective To explore the teaching effect of case-integrated scenario simulation instruction model on proba-tionary instruction of acute upper gastrointestinal bleeding.Methods A total of 40 medical students of grade 2021 majoring in clinical medicine,namely,Nanshan Class,from Guangzhou Medical University were selected as participants.The students were randomly divided into two groups,with 22 as an experimental group and 18 as a control group.The former group received the case-integrated based scenario simulation teaching model,while the latter adopted the traditional bedside teaching model.The teaching content was on acute non-variceal upper gastrointestinal bleeding.Results There was no statistically significant differ-ence in the total score of gastroenterology between the experimental group and the control group(P＞0.05).The experimental group scored significantly higher in the gastrointestinal bleeding-related contents compared to the control group(P＜0.05).The post-class survey revealed that the majority of the students in the research group expressed their high-level satisfaction with the new instruction model and demonstrated their greater interests in participation in the new instruction model.Conclusion The case-integrated scenario simulation instruction model demonstrates significant superiority to the traditional bedside teaching model in terms of stimulating learning interests,cultivating medical professionalism,and enlivening classroom atmosphere.It is suitable for practical teaching in gastroenterology and can be widely adopted as routine probationary teaching for undergraduate students.

The incidence of stroke increases year by year.It seriously affects the quality of life in patients.The pathogenesis of stroke is related to a variety of factors,involving genetic polymorphisms,biochemical mechanisms,and inflammatory effect.Among them,vascular endothelial growth factor (VEGF) has become one of the hotspots of research on the pathogenesis of stroke in recent years.This article reviews the correlation between VEGF gene polymorphism and stroke.