In order to fulfill the new requirement of educational and teaching reform in the new era, the Teaching and Research Section of Parasitology in Guangxi Medical University have constructed online courses of Parasites Invasion— Human Parasitology on the platform of Xueyin Online, providing resources in professional learning and general education. In the construction concept, we recombine teaching content to give consideration to both scientificity and interest. In terms of the curriculum content, the curriculum includes micro lecture, PPT, in-lass quiz, case analysis and other diversified teaching resources. In the curriculum management, teachers interact with students in real time with the help of various functions of the platform to fully play the role of supervision. In the assessment, teachers pay attention to students' learning process and carry out comprehensive evaluation. Since the online course was put into operation, good teaching effects has been achieved.

Objective:To evaluate the efficacy and safety of endoscopic submucosal dissection (ESD) for early hypopharyngeal carcinoma and precancerous lesions.Methods:Clinical data of 41 patients who received ESD for early hypopharyngeal carcinoma and precancerous lesions from August 2013 to August 2019 in the Department of Endoscopy of Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College were retrospectively analyzed. Main outcome measurements included operation completion rate, operation time, en bloc resection rate, R0 resection rate, complication rate and recurrence.Results:ESD was successfully completed in all 41 cases, with a success rate of 100.0% and a mean time of 49.1 min (ranged 10-110 min). Fifty-four lesions underwent en bloc resection, with an en bloc resection rate of 98.2% (54/55), of which 41 had negative horizontal and vertical margins, and the R0 resection rate was 74.5% (41/55). During the operation of 55 lesions, there was a small amount of blood oozing on the wound surface, and electrocoagulation with thermal biopsy forceps could successfully stop the bleeding. No perforation occurred, and 2 cases (4.3%) had delayed bleeding after ESD, and hemostasis was successful under emergency endoscopy. Postoperative endoscopy showed that 1 case (2.2%) had esophageal entrance stenosis, and the obstruction was relieved after repeated water balloon dilatation. The follow-up period ranged from 3 to 72 months, and the median time was 18 months. One case was found to have mucosal lesions in the same part of the hypopharynx and received ESD treatment again. Follow-up to October 2020, no residual lesions and recurrence were found.Conclusion:ESD is a safe and effective option for the treatment of early hypopharyngeal carcinoma and precancerous lesions, which is worthy of clinical application.

Three cases of lower lumbar nerve root gangliomas with spinal instability or lumbar disc herniation are reported. The first patient was treated for lumbosacral pain and discomfort for more than 10 days. Preoperative diagnosis was L 5S 1 intervertebral instability, L 5 bilateral spondylolysis, and L 5S 1 left intervertebral foraminal space occupying lesions to be investigated, the tumor was removed intraoperatively and sent to pathology. Meanwhile, L 5S 1 posterior interbody bone graft fusion and internal fixation were performed. The second patient presented for 1 month due to left lumbar and leg pain and discomfort. Preoperative diagnosis was L 4-5 intervertebral instability and L 4-5 intervertebral disc herniation. Intraoperative exploration revealed a nerve root mass on the left side of L 5, which was surgically removed and sent to pathology. Meanwhile, posterior decompression of L 4 and L 5 intervertebral bone grafting and internal fixation were performed. The third patient presented for 4 days with right lumbar and leg pain and discomfort. Preoperative diagnosis was L 3-4, L 4-5 and L 5S 1 intervertebral disc herniation. Intraoperative exploration found a right nerve root mass of S 1, which showed invasive growth and was closely surrounded by nerve fibers. Partial resection of the mass was sent to pathology, and posterior decompression and internal fixation of L 4-5 and L 5S 1 bone grafting and fusion were performed at the same time. All 3 patients were confirmed to be ganglion neuroma by postoperative pathological examination. Three patients recovered well after surgery. Spinal ganglion cell tumor is mainly originated from primitive neural crest cell migration differentiation of sympathetic ganglion cells, and can also be derived from the sympathetic nerve and peripheral nerves. It is seen more at retroperitoneal and mediastinal, lumbosacral nerve root ganglion cells tumor is rare. Clinically, it is very close to intervertebral disc herniation and difficult to distinguish, often found during operations and less can be clearly diagnosed before operation. Surgical resection is the main treatment for ganglion cell neuroma.

Objective:To discuss the efficacy and safety of endoscopic papillectomy of major duodenal papilla neoplasms.Methods:The clinical-pathological data of 21 patients who were admitted to the Department of Endoscopy, Cancer Hospital, Chinese Academy of Medical Sciences and underwent endoscopic papillectomy of major duodenal papilla neoplasms from January 2014 to January 2020 were retrospectively studied, their postoperative outcomes and complication were also analyzed.Results:Tweenty-one patients were successfully performed endoscopic papillectomy of major duodenal papilla neoplasms. The resected lesions varied between 0.5-2.8 cm. Completed lesion was resected in 19 cases and lesion blocks in 2 cases. The incidence of postoperative complication was 52.4% (11/21), including 8 cases of postoperative bleeding (38.1%). Five patients stopped bleeding after endoscopic hemostasis and 3 patients stopped after interventional embolization. Two patients experienced perforation (9.5%) and recovered after conservative treatment including anti-inflammatory treatment and abdominal drainage. Five patients had pancreatitis (23.8%) and recovered after treatment with pre-somatostatin and anti-inflammatory rectal suppository. Preoperative pathological results of 21 patients suggested that 11 were high-grade intraepithelial neoplasia and 8 were low-grade intraepithelial neoplasia, and 2 were chronic inflammation. Postoperative pathological results suggested that 4 were adenocarcinoma, and the rest 17 were adenoma. The coincidence rate of preoperative biopsy results and postoperative pathology was 38.1%(8/21), and underestimate of the pathological stage occurred in 11 patients (52.4%) during the preoperative biopsy, overestimate occurred in two patients (9.5%). Four cases had a positive incisal margin. All patients had good prognoses and no death event occurred during the follow-up period.Conclusions:Early-stage major duodenal papilla neoplasms should be treated with aggressive resection. Endoscopic papillectomy of duodenal papilla neoplasms is safe, effective, and can be recommended as the preferred procedure for major duodenal papilla neoplasms.

Objective:To determine the potential risk factors of delayed hemorrhage after endoscopic submucosal dissection (ESD) in patients with early gastric carcinomas or precancerous lesions.Methods:The clinical data of 637 patients with early gastric carcinomas (EGC) who treated with ESD in Department of Endoscopy at Cancer Hospital, Chinese Academy of Medical Sciences, from August 2013 to August 2019, were retrospectively analyzed. Univariate analysis and multivariate logistic analysis were conducted to evaluate the risk factors associated with delayed bleeding.Results:A total of 699 lesions in 637 patients, of which 696 lesions were resected enbloc, the curative resection rate was 92.1% (644/699). The pathological diagnosis after ESD showed that 46 cases were low-grade intraepithelial neoplasia, 71 were high-grade intraepithelial neoplasia, and 582 were cancer. Delayed bleeding occurred in 74 lesions, while other 625 lesions without postoperative bleeding. The incidence was 10.6%. Compared with the non-bleeding group, there were statistically significant differences in the maximum length of the lesion, the gross shape of the lesion, the control of intra operative bleeding, and the operation time in the delayed bleeding group ( P<0.05). Multivariate logistic regression analysis showed that the maximum length of the lesion and the gross shape of the lesion were independent factors of delayed bleeding after ESD. Delayed bleeding was inclined to occur in patients with lesion size ≥3.0 cm ( OR=1.958, 95% CI: 1.162-3.299) and the superficial and flat lesion ( OR=10.598, 95% CI: 1.313-85.532) after ESD. Conclusions:The maximum length of the lesion and the gross shape of the lesion are independent impact factors of delayed bleeding occurring in patients with EGC and precancerous lesions after ESD. Patients with lesion size≥3 cm, or superficial flat lesion should be paid attention after ESD operation. It needs to take timely measures to prevent the very likely bleeding in order to ensure postoperative recovery and improve the quality of life for postoperative patients.

Objective:To discuss the efficacy and safety of endoscopic papillectomy of major duodenal papilla neoplasms.Methods:The clinical-pathological data of 21 patients who were admitted to the Department of Endoscopy, Cancer Hospital, Chinese Academy of Medical Sciences and underwent endoscopic papillectomy of major duodenal papilla neoplasms from January 2014 to January 2020 were retrospectively studied, their postoperative outcomes and complication were also analyzed.Results:Tweenty-one patients were successfully performed endoscopic papillectomy of major duodenal papilla neoplasms. The resected lesions varied between 0.5-2.8 cm. Completed lesion was resected in 19 cases and lesion blocks in 2 cases. The incidence of postoperative complication was 52.4% (11/21), including 8 cases of postoperative bleeding (38.1%). Five patients stopped bleeding after endoscopic hemostasis and 3 patients stopped after interventional embolization. Two patients experienced perforation (9.5%) and recovered after conservative treatment including anti-inflammatory treatment and abdominal drainage. Five patients had pancreatitis (23.8%) and recovered after treatment with pre-somatostatin and anti-inflammatory rectal suppository. Preoperative pathological results of 21 patients suggested that 11 were high-grade intraepithelial neoplasia and 8 were low-grade intraepithelial neoplasia, and 2 were chronic inflammation. Postoperative pathological results suggested that 4 were adenocarcinoma, and the rest 17 were adenoma. The coincidence rate of preoperative biopsy results and postoperative pathology was 38.1%(8/21), and underestimate of the pathological stage occurred in 11 patients (52.4%) during the preoperative biopsy, overestimate occurred in two patients (9.5%). Four cases had a positive incisal margin. All patients had good prognoses and no death event occurred during the follow-up period.Conclusions:Early-stage major duodenal papilla neoplasms should be treated with aggressive resection. Endoscopic papillectomy of duodenal papilla neoplasms is safe, effective, and can be recommended as the preferred procedure for major duodenal papilla neoplasms.

Objective:To determine the potential risk factors of delayed hemorrhage after endoscopic submucosal dissection (ESD) in patients with early gastric carcinomas or precancerous lesions.Methods:The clinical data of 637 patients with early gastric carcinomas (EGC) who treated with ESD in Department of Endoscopy at Cancer Hospital, Chinese Academy of Medical Sciences, from August 2013 to August 2019, were retrospectively analyzed. Univariate analysis and multivariate logistic analysis were conducted to evaluate the risk factors associated with delayed bleeding.Results:A total of 699 lesions in 637 patients, of which 696 lesions were resected enbloc, the curative resection rate was 92.1% (644/699). The pathological diagnosis after ESD showed that 46 cases were low-grade intraepithelial neoplasia, 71 were high-grade intraepithelial neoplasia, and 582 were cancer. Delayed bleeding occurred in 74 lesions, while other 625 lesions without postoperative bleeding. The incidence was 10.6%. Compared with the non-bleeding group, there were statistically significant differences in the maximum length of the lesion, the gross shape of the lesion, the control of intra operative bleeding, and the operation time in the delayed bleeding group ( P<0.05). Multivariate logistic regression analysis showed that the maximum length of the lesion and the gross shape of the lesion were independent factors of delayed bleeding after ESD. Delayed bleeding was inclined to occur in patients with lesion size ≥3.0 cm ( OR=1.958, 95% CI: 1.162-3.299) and the superficial and flat lesion ( OR=10.598, 95% CI: 1.313-85.532) after ESD. Conclusions:The maximum length of the lesion and the gross shape of the lesion are independent impact factors of delayed bleeding occurring in patients with EGC and precancerous lesions after ESD. Patients with lesion size≥3 cm, or superficial flat lesion should be paid attention after ESD operation. It needs to take timely measures to prevent the very likely bleeding in order to ensure postoperative recovery and improve the quality of life for postoperative patients.

Objective:To provide a scientific basis for reducing the rate of invalid ambulance attendance and the establishment of grades dispatch system through a retrospective analysis of the invalid ambulance attendance in prehospital emergency care.Methods:The data of the invalid ambulance attendance was collected in Huazhong University of Science and Technology Union Shenzhen Hospital (the only tertiary hospital of in Nanshan District) from 2014 to 2018, and the reasons of the invalid ambulance attendance, the time period during the invalid ambulance attendance occurred (every 3 hours was divided into one time period), and the reasons of ambulance calling were statistically analyzed.Results:① The invalid ambulance attendance rates showed a fluctuating decrease trend year by year from 2014 to 2018, the rates were 31.22% (2 515/8 055), 26.94% (2 147/7 970), 29.80% (2 398/8 046), 25.69% (1 844/7 177) and 21.89% (1 686/7 703), respectively. The total invalid ambulance attendance rate was 27.19% (10 590/38 951) in the five years. ② The top three reasons for the invalid ambulance attendance were cancelled calls, departure before the ambulance arrived, and going to hospital by themselves, accounting for 36.87%, 25.08%, and 17.03%, respectively. The constituent ratios of the causes of invalid ambulance attendance in each year were different with statistical significance (χ 2 = 217.626, P < 0.001). ③ The top three time period of invalid ambulance attendance occurred at 21:00-23:59, 18:00-20:59 and 09:00-11:59, accounting for 16.86%, 14.95% and 13.54%, respectively. There was no statistical significance in the distribution of time period in each year (χ 2 = 32.571, P = 0.252). ④ The top five reasons for ambulance calling of invalid ambulance attendance were fainting/syncope, trauma, alcoholism, traffic accident injuries, and brawls, accounting for 20.13%, 15.67%, 9.97%, 8.64%, and 6.45%, respectively, and there was statistically significant difference in the distribution of the reason for ambulance calls in each year (χ 2 = 194.213, P < 0.001). Conclusion:The invalid ambulance attendance rate is high in Nanshan District of Shenzhen. Improving the professional level and triage ability of the dispatchers, improving the system construction of prehospital emergency care system and increasing social education are conducive to reduce invalid ambulance attendance rate.

Objective: To evaluate the short-term outcomes and safety of submucosal tunneling endoscopic resection (STER) for submucosal tumors (SMT) originating from muscularis propria (MP) layer at esophagogastric junction. Methods: The clinical data of 31 patients with SMT originating from MP layer at esophagogastric junction underwent STER were collected and retrospectively analyzed. Results: The success rate of STER of the thirty-one patients was 100%. The mean tumor size was (2.5±1.3) cm and the average operative time was (95.9±56.7) min. Perforation occurred in 3 patients and was successfully clipped by endo-clips during operation. One patient developed delayed bleeding and the bleeding was stopped by endoscopic hemostasis. Twenty-nine leiomyomas and two stromal tumors (GIST) were finally pathologically diagnosed. No local recurrence and distant metastasis were noted during the mean 15.4 months follow-up of 20 cases. According to the lesion size, 31 patients who received STER were divided into two groups. The operation time of maximum diameter ≥3.5 cm group was (134.0±70.6) min, significantly longer than (80.3±42.6) min of maximum diameter <3.5 cm group (P=0.014). However, the en bloc removal rate, postoperative hospital stay and the complication incidence between the two groups had no obvious differences (P>0.05). Univariate analysis showed that the piecemeal removal group had longer tumor diameter, higher incidence of irregular tumor morphology, and longer operative time than the en bloc removal group (all P<0.05). Stepwise logistic regression analysis showed that irregular shape was a risk factor for failure of en bloc removal (OR=18.000, 95% CI: 1.885~171.88, P=0.012). Conclusion As a new method of minimally invasive treatment, STER technology appears to be a safe and effective option for patients with SMT originating from MP layer at esophagogastric junction.

Objective To explore the value of applying flipped classroom in human parasitology. Methods Totally 430 students of 5-year program were divided into experimental group and control group. The experimental class received human parasitology teaching through flipped classroom teaching mode, while the control class received traditional teaching. The effect of teaching was evaluated by questionnaire and examination. The data were analyzed through t-test. Result Meanwhile, statistical difference was found in aver age score of total between experiment group and control group [(68.2 ±8.6) vs. (66.6 ±11.0), P=0.032]. There was also statistical difference in average score of comprehensive analysis [(16.4±3.2) vs. (16.1 ±3.9), P=0.038]. Questionnaire survey of satisfaction showed that 191 students of experimental class (90.95%) felt new teaching mode could improve autonomous learning ability, 199 students (94.76%) in-creased interest in learning;185 students (88.10%) had more interactive with teachers, 178 students (84.76%) enhanced cooperation between st udents, 186 students (88.57%) approved of small group discussion learning and 165 students (78.57%) had no extra burden. Conclusion Flipped classroom teaching mode can improve students' autonomous learning ability and cultivate their abilities of independent thinking, cooperation, criti-cism, innovation, analyzing and solving problems. Thus this new teaching mode is worthy of reference and popularization.