Objective To investigate the application value of quantitative relaxation parameters based on synthetic MRI technology in the differential diagnosis of parotid gland tumors.Methods Conventional MRI and synthetic MRI data of 59 patients with patho-logically confirmed parotid gland tumors were analyzed retrospectively.T1,T2,and proton density(PD)values of the tumor were extracted from T1,T2 and PD mapping.The differences in quantitative relaxation parameters of pleomorphic adenomas,Warthin tumors,and malignant tumors were further compared.Diagnostic performance of each quantitative relaxation parameter was assessed and com-pared via receiver operating characteristic(ROC)curve and DeLong test.Results T2 value was significantly higher in pleomorphic adenomas than that in malignant tumors(P<0.05).The T1,T2,and PD values of pleomorphic adenomas and malignant tumors were significantly higher than those of Warthin tumors(P<0.05).The area under the curve(AUC)of the T2 value in differentia-ting pleomorphic adenomas from malignant tumors was 0.794.The AUC for T1 value(0.939)in differentiating Warthin tumors from malignant tumors was significantly higher than that of T2(0.873,P=0.341)and PD(0.927,P=0.891)values,without sta-tistically significant difference.The AUC for T2 value(0.968)in differentiating pleomorphic adenomas from Warthin tumors was significantly higher than that of T1(0.931,P=0.360)and PD(0.876,P=0.120)values,without statistically significant difference.Conclusion Quantitative relaxation parameters based on synthetic MRI technology may contribute to differentiating pleomorphic adenomas,Warthin tumors,and malignant tumors of the parotid gland.

Objective To study the population genetic structure and phylogenetic relationships by combining Y-STR haplotype genetic information from the Han population in Dalian with 32 domestic and foreign groups.Methods Blood samples of 958 Han male volunteers from Dalian were collected.Genetic typing of 42 genetic loci was completed using Y-STR fluorescent reagent kits and capillary electrophoresis.Related forensic parameters were calculated.Nei's standard genetic distances among 33 populations based on 17 Y-STR loci were computed,in order to create a principal coordinate analysis as well as construct a phylogenetic tree.Results The analysis of genetic polymorphisms at 42 Y-STR loci revealed 30 unconventional alleles at 10 loci.Genetic analysis of the population based on 17 Y-STR loci confirmed that Dalian's Han population had the closest genetic distance to the Anshan's Han population,followed by populations from Henan,Heilongjiang,Jilin,Shandong,and Chongqing.Furthermore,the genetic distances between the Han population in Dalian and the Qiang population in Beichuan or the Miao population in Guizhou were relatively closer than that to the Manchu population living in Liaoning.Conclusion The genetic distance between the Han population in Dalian and other groups is not entirely proportional to ethnicities and geographical proximity.Both population migration and ethnic assimilation or isolation may have influence on it.

Objective:To explore the feasibility of applying BOPPPS (B-bridge in, O-objective, P-pre-assessment, P-participatory learning, P-post-assessment, S-summary) course design mode in the teaching of internal medicine practice for nursing undergraduates.Methods:A total of 73 nursing interns of Kunming Medical University were selected as subjects and divided into the experimental group ( n=30) and the control group ( n=43). The experimental group adopted the practice teaching method based on BOPPPS model, while the control group adopted the traditional teaching method. Students' evaluation was collected by questionnaire. The students' comprehensive reasoning ability, holistic nursing skills ability and clinical nursing evaluation ability were evaluated by taking out questions from the question bank. And the results of teachers' evaluation on the participation of case study and problem solving in the process of students' internship were collected. SPSS 20.0 was used for t-test. Results:The students' evaluation of the practice process in the experimental group (86.81±2.85) was significantly better than that in the control group (82.61±3.82) ( P<0.001). The experimental group was significantly better than the control group in comprehensive reasoning of clinical thinking and assessment of holistic nursing ability ( P <0.001). Teachers' evaluation in the experimental group was better than that in the control group ( P <0.05). The overall effect of the experimental group (20.60±1.73) was significantly better than that of the control group (17.84±1.70) ( P <0.001). Conclusion:BOPPPS mode is helpful for teachers to carry out and demonstrate holistic nursing teaching with symptoms as the core according to the overall teaching objectives of nursing internal medicine, optimize the time arrangement and knowledge structure, improve the practice efficiency, and promote the establishment of holistic nursing thinking mode of students.

Dens invaginatus is a rare developmental anomaly of the teeth that is caused by the infolding of enamel organs or the penetration of their proliferations into dental papillae before calcification has occurred. The presence of double dens invaginatus is extremely rare. This paper describes the use of cone beam computed tomography in the evaluation of a maxillary lateral incisor with double dens invaginatus and periapical periodontitis. The tooth was treated through microscopic root canal therapy. The tooth was free of clinical symptoms, and the periradicular lesion narrowed during the follow-up period of 1 year.
Humans ; Dental Pulp Cavity/abnormalities* ; Dens in Dente/pathology* ; Incisor/pathology* ; Root Canal Therapy ; Periapical Periodontitis/pathology*

Objective    To investigate the effectiveness and safety of robotic lobectomy in clinical N0 lung malignant tumor≥3 cm. Methods    We retrospectively analyzed the clinical data of 182 patients with lung malignant tumor≥3 cm receiving robotic or thoracoscopic lobectomy at Shanghai Chest Hospital in 2019. The patients were divided into a robotic surgery group (RATS group) and a thoracoscopic surgery group (VATS group). There were 39 males and 38 females with an average age of 60.55±8.59 years in the RATS group, and 51 males and 54 females with an average age of 61.58±9.30 years in the VATS group. A propensity score matching analysis was applied to compare the operative data between the two groups. Results    A total of 57 patients were included in each group after the propensity score matching analysis. Patients in the RATS group had more groups of N1 lymph node dissected (2.53±0.83 groups vs. 2.07±0.88 groups, P=0.005) in comparison with the VATS group. No statistical difference was found in operation time, blood loss, postoperative hospital stay, number of N1 and N2 lymph nodes dissected, groups of N2 lymph node dissected, lymph node upstage rate or postoperative complications. The hospitalization cost of RATS was higher than that of VATS (P<0.001). Conclusion    In contrast with thoracoscopic lobectomy, robotic lobectomy has similar operative safety, and a thorough N1 lymphadenectomy in patients with clinical N0 lung malignant tumor≥3 cm.

Objective    To compare the perioperative outcomes between robot-assisted complex segmentectomy and simple segmentectomy for stage ⅠA non-small cell lung cancer (NSCLC). Methods    The clinical data of 285 patients with NSCLC undergoing robot-assisted thoracic surgery (RATS) in our hospital from January 2015 to August 2021 were retrospectively analyzed. There were 105 males and 180 females aged 23-83 years. The patients were divided into a complex segmentectomy group (n=170) and a simple segmentectomy group (n=115) according to tumor location and surgical method. The clinical pathological baseline characteristics and perioperative outcomes between the two groups were compared, including operative time, blood loss volume, dissected lymph nodes, conversion rate, postoperative duration of drainage, postoperative hospital stay, the incidence of persistent air leakage and postoperative 30 d mortality. Results    There was no statistical difference in baseline data between the two groups (P>0.05). No postoperative 30 d death was observed. One patient in the complex segmentectomy group was transferred to thoracotomy. No statistical difference was observed between the two groups in the operative time (97.36±38.16 min vs. 94.65±31.67 min, P=0.515),  postoperative duration of drainage (3.69±1.85 d vs. 3.60±1.90 d, P=0.679), postoperative hospital stay (4.07±1.85 d vs. 4.05±1.97 d, P=0.957), dissected lymph nodes (5.15±3.53 vs. 5.13±2.93, P=0.952), incidence of blood loss volume<100 mL (98.2% vs. 99.1%, P=0.650), and incidence of postoperative persistent air leakage (6.5% vs. 5.2%, P=0.661). Conclusion    The safety and effectiveness of robot-assisted complex segmentectomy and simple segmentectomy are satisfactory in the treatment of stage ⅠA NSCLC. The perioperative results of RATS complex segmentectomy and simple segmentectomy are similar.

Objective:To explore the present situation of medical students' professionalism cognition and provide reference for medical personnel training and medical education.Methods:A cross-sectional survey was conducted on medical students among 2 affiliated hospitals of a medical university in H province by cluster sampling. Exploratory factor analysis and reliability and validity test were carried out and a descriptive analysis of the present situation of professionalism was conducted by SPSS 20.0. Amos21.0 software was used for a confirmatory factor analysis on the samples.Results:The measurement scale had good reliability and validity, and the Cronbach alpha coefficient of the scale was 0.901. The average professionalism score of the medical students was about 80 points. The score of "physical and mental status and self-development ability" was the highest (83.65 points), and the lowest score was "academic ability" (72.21 points). There was a little difference in the professionalism cognition between the two hospitals, with significant differences between the dimension "respect and care" and "responsibility".Conclusion:This study has initially formed a medical professionalism measurement scale with good reliability and validity. The professionalism of medical students in the 2 affiliated hospitals of a medical school in Province H is in good condition as a whole. In the future, medical education should pay more attention to the combination of basic professional knowledge and clinical practice of medical students, and change the training model of medical students in order to improve the academic ability of medical students and medical students' overall cognition of professionalism.

Objective:To dynamically trace the migration and therapeutic effects of human bone marrow mesenchymal stem cells (MSCs) in mice with liver injury after cell transplantation through in vivo bioluminescent imaging (BLI).Methods:The MSCs were transfected with the lentivirus CMV-Luciferase2-mKate2 and mKate2 positive cells were purified and screened by fluorescence-activated cell sorting (FACS) after 96 h. The purified MSCs-R (MSCs-CMV-Luciferase2-mKate2) were used by in vitro and in vivo BLI. The mice (male BALB/c nude mice) were divided into 4 groups with 9 mice per group by random number table method, including (1) Liver injury experimental group: The liver injury model was established by intraperitoneal injection of CCl 4, and MSCS-R transplantation through spleen injection was performed 24 h later; (2) Control experimental group: The same volume of phosphate buffer (PBS) was injected intraperitoneally, and MSCS-R transplantation through spleen injection was performed 24 h later; (3) Liver injury group: Liver injury model was established and PBS was injected into the spleen;(4) Blank group: The mice were intraperitoneally injected of PBS.BLI was performed daily after cell transplantation until light signals disappeared in the liver region, and the pathological examination of liver tissue was obtained 14 d after MSCs-R transplantation. Linear regression analyses were performed to determine the correlation between the optical signal intensity and the number of cells, and statistical differences of the optical signal intensity between liver injury experimental group and control experimental group were evaluated using the Student′s t test. Results:The MSCs were readily transfected with lentivirus CMV-Luciferase2-mKate2 for 96 h. The transfected MSCs were purified by FACS and more than 95% of MSCs were mKate2 positive. The optical signal intensity of MSCs-R detected by BLI in vitro significantly correlated with cell numbers in vitro (R 2=0.980). In both of liver injury experimental group and control experimental group, cell migration to the liver was observed on the first day after intrasplenic transplantation of MSCs-R, and the optical signal intensity in the area of liver of liver injury experimental group was higher than that of control experimental group ( t=15.476, P<0.001). The optical signal intensity in the hepatic area was observed in 11 d after transplantation in liver injury experimental group, compared to control experimental group in 5 d. Optical signal was not detected in mice in the other two groups. Histopathology showed that the degree of liver injury after MSCs-R transplantation was significantly lower in liver injury experimental group than control experimental group. Conclusions:The dynamical migration of MSCs transplanted to the spleen and settled in the damaged liver could be tracked by BLI, and liver injury can prompt MSCs directionally migrate to the damaged tissues and play their role in repairing liver injury.

Objective:Based on the current medical environment, to learn about cognition status of doctor-patient relationship among medical students and analyze causes of the tension between doctors and patients.Methods:Using the self-designed questionnaire "Clinical Medical Students' Cognition Survey on Occupational Status and Doctor-Patient Relationship", a cross-sectional survey was conducted on 527 medical students from 5-year and 7-year clinical program in Batch 2014 in a medical university in Heilongjiang Province. The survey mainly analyzed the causes of the tension between doctors and patients from the level of medical staff, patients and their families, hospitals and society. SPSS 22.0 was used for descriptive statistics and chi-square test.Results:The results showed that 93.7% of the medical students believed that the current doctor-patient relationship was not harmonious. There were cognitive differences among medical students in different gender ( P=0.029), first contact clinical grade ( P=0.003) and professional identity ( P<0.001). Conclusion:Medical students have a poor evaluation towards the current doctor-patient relationship. In order to construct harmonious doctor-patient relationship in the future, we can try to take measures such as carrying out relevant courses of doctor-patient communication, improving the medical students' communication skills and enhancing their professional identity.

Objective The purpose of this study was to evaluate whether whole-tumor histogram-based analysis of readout-segmented echo-planar diffusion-weighted imaging (RESOLVE-DWI) ADC map can help in the discrimination of parotid gland tumors(pleomorphic adenoma, Warthin tumor, malignant parotid gland tumor). Methods The MR images(pre / post-contrast enhanced MRI, RESOLVE-DWI, ADC map) of 47 patients with a biopsy-or surgery-proven pleomorphic adenomas, 25 patients with Warthin tumors and 36 patients with malignant parotid gland tumors were retrospectively analyzed. Histogram-based analysis was performed with the software MaZda. ROIs were drawn on every section of the ADC map containing the tumor, then 12 Parameters(Area, MinNorm, MaxNorm, Mean,Variance, Skewness, Kurtosis, Perc.1％, Perc.10％, Perc.50％, Perc.90％, Perc.99％) derived from histogram were calculated. Statistical analysis among the three groups (One-way ANOVA or Kruskal-Wallis test) were performed to find out the statistical significance of each histogram parameter. Then LSD test or Mann-Whitney U test was used for pairwise comparison between groups. And the differential efficiency of each parameter was determined using ROC analysis. Results Overall, 9 parameters (MinNorm, MaxNorm, Mean, Variance, Skewness, Perc. 10％, Perc. 50％, Perc. 90％, Perc. 99％) among three groups were shown to be statistically significant (P<0.05). Between the pleomorphic adenomas and Warthin tumors, these 9 parameters were of statistical significance. Perc.50％revealed the highest diagnostic efficiency, followed by Mean and Perc.10％. Between the pleomorphic adenomas and malignant parotid gland tumors, also all these 9 parameters were of statistical significance. Mean was revealed to have the highest diagnostic efficiency, followed by Perc. 10％ and Perc. 90％. However, between the Warthin tumors and malignant parotid gland tumors, only 5 parameters (MinNorm, Mean, Skewness, Perc. 10％, Perc. 50％) were statistically significant. MinNorm was revealed to have the highest diagnostic efficiency, followed by Perc. 50％ and Perc. 10％. Generally, Mean, Perc. 10％ and Perc. 50％ were more effective in the differential diagnosis of these three types common parotid neoplasms. Conclusion Whole-tumor histogram analysis of ADC maps are effective in differentiating common parotid neoplasms.