Objective To investigate the diagnosis value of contrast-enhanced ultrasound (CEUS) in the differentiation of hepatocellular carcinoma (HCC) and focal nodular hyperplasia (FNH) of the liver with ≤3 cm of maximum diameter. Methods The image characteristics in 48 lesions of HCC with maximum diameter≤3 cm and 48 lesions of FNH with maximum diameter≤3 cm confirmed by pathology were retrospectively analyzed. The phase changes, enhancement patterns and enhancement characteristics of the lesions in the two groups were compared. Results All lesions in the two groups showed high-echo in the arterial phase. The contrast arrival time in HCC group and FNH group was 17(15, 19) s and 15(12, 18.75) s (P＝0.017); the peak time in the two groups was 21(17, 25) s and 22(19, 26) s (P＞0.05). The main enhancement patterns of HCC group and FNH group in arterial phase were homogeneous enhancement and centrifugal enhancement, respectively. All HCC lesions showed homogeneous enhancement, which was significantly higher than FNH (2.08%, P＜0.05); 97.91% of FHN lesions showed centrifugal enhancement, which was higher that of HCC lesions (0, P＜0.05). During the CEUS process, 87.5% of HCC lesions showed “rapid fill-in and rapid wash-out”, which was significantly higher than that of FNH lesions（8.33%，P＜0.05）; 91.67% of FNH lesions showed “rapid fill-in” and “synchronous/slow wash-out” which was significantly higher than that of HCC lesions （12.50%，P＜0.05）. Conclusion CEUS is helpful in the differential diagnosis of FNH and HCC with maximum diameter≤3 cm．

Objective:To establish a nomogram prediction model for recurrence within 2 years after radical resection of hepatocellular carcinoma (HCC) based on clinical and ultrasonographic characteristics.Methods:Clinical data from 405 HCC patients (including 327 males and 78 females), aged 60 (53, 66) years old, who underwent radical hepatectomy in the Zhongshan Hospital, Fudan University, from January to December 2021, were retrospectively collected. The patients were divided into two groups: the training group ( n=283) and the validation group ( n=122). Based on recurrence within 2 years after surgery, the 283 patients in the training group were further categorized into the recurrence group ( n=73) and the non-recurrence group ( n=210). Among the 122 patients in the validation group, 33 had recurrence within 2 years, while 89 did not. Data on age, microvascular invasion, alpha-fetoprotein (AFP), AFP lentil lectin-reactive fraction (AFP-L3), protein induced by vitamin K absence or antagonist-II (PIVKA-II), tumor number, and enhancement homogeneity were collected. Logistic regression analysis was performed on the training group to identify risk factors associated with postoperative recurrence, and a nomogram model for predicting HCC recurrence was constructed based on these factors. Calibration curves were used to compare the consistency between predicted and actual outcomes in both the training and validation groups. Results:Multivariate logistic regression analysis revealed that younger age ( OR=0.976, 95% CI: 0.953-1.000, P=0.004), higher AFP-L3 ( OR=1.066, 95% CI: 1.014-1.120, P=0.012), higher PIVKA-II ( OR=1.000, 95% CI: 1.000-1.001, P=0.042), multiple tumors ( OR=0.399, 95% CI: 0.225-0.706, P=0.038), and heterogeneous enhancement ( OR=0.472, 95% CI: 0.243-0.916, P=0.045) were significant risk factors for recurrence after partial hepatectomy in HCC patients. The nomogram constructed based on these variables had a C-index of 0.87 (95% CI: 0.81-0.93) in the training group and 0.83 (95% CI: 0.77-0.89) in the validation group. The calibration curves for predicting recurrence within 2 years after partial hepatectomy in HCC patients showed a high degree of fit in both the training and validation groups, indicating a good agreement between predicted and actual outcomes. Conclusion:The nomogram model constructed based on preoperative clinical and ultrasonographic characteristics can effectively predict the risk of recurrence within 2 years after radical resection of HCC.

Objective: To investigate the status of insomnia, Internet addiction, and depressive symptoms among medical students and to analyze the effect of Internet addiction on insomnia and the mediating role of depressive symptoms, in order to provide a basis for the development of targeted interventions and measurements for medical students. Methods: A stratified whole group sampling method was used to select full-time college students from three medical universities in Anhui Province. The Chinese version of Insomnia Severity Index (ISI), Internet Addiction Test (IAT) scale and 9-item Patient Health Questionnaire (PHQ-9) were used to evaluate the symptoms of insomnia, Internet addiction and depressive in students. A multivariate Logistic regression analysis was used to explore the factors influencing insomnia among medical students and to analyze the relationship between insomnia with Internet addiction and depressive symptoms, respectively. Results: The overall rate of Internet addiction was 49.5%, depressive symptoms was 39.5%, insomnia was 18.6%. High academic stress, and the presence of surrounding people diagnosed with COVID-19 were associated with a higher risk of insomnia ( P <0.05). The higher the level of Internet addiction (mild, OR =2.60; moderate/severe, OR =4.21) and depression. (mild, OR =6.35; moderate/severe, OR =19.32), the higher the risk of insomnia. Mediated effect analysis showed that Internet addiction had a direct predictive effect ( β =0.02, P <0.05) on insomnia and also indirectly affected insomnia through depression (indirect effect=0.07，95% CI =0.06-0.08). Conclusion The detected rates of insomnia, Internet addiction and depressive symptoms are high among medical students in Anhui Province, and Internet addiction and depressive symptoms are risk factors for insomnia, which should be given more attention and appropriate interventions when necessary to improve their physical and mental health.

Objective     To investigate the safety of thoracic surgery for high-altitude patients in local medical center. Methods    We retrospectively collected 258 high-altitude patients who received thoracic surgery in West China Hospital, Sichuan University (plain medical center, 54 patients) and People's Hospital of Ganzi Tibetan Autonomous Prefecture (high-altitude medical center, 204 patients) from January 2013 to July 2019. There were 175 males and 83 females with an average age of 43.0±16.8 years. Perioperative indicators, postoperative complications and related risk factors of patients were analyzed. Results    The rate of minimally invasive surgery in the high-altitude medical center was statistically lower than that in the plain medical center (11.8% vs. 55.6%, P<0.001). The surgical proportions of tuberculous empyema (41.2% vs. 1.9%, P<0.001) and pulmonary hydatid (15.2% vs. 0.0%, P=0.002) in the high-altitude medical center were statistically higher than those in the plain medical center. There was no statistical difference in perioperative mortality (0.5% vs. 1.9%, P=0.379) or complication rate within 30 days after operation (7.4% vs. 11.1%, P=0.402) between the high-altitude center and the plain medical center. Univariate and multivariate analyses showed that body mass index≥ 25 kg/m2 (OR=8.647, P<0.001) and esophageal rupture/perforation were independent risk factors for the occurrence of postoperative complications (OR=15.720, P<0.001). Conclusion    Thoracic surgery in the high-altitude medical center is safe and feasible.

Objective:To evaluate the value of shear wave dispersion imaging in identifying inflammatory reaction zone after liver ablation in rabbits.Methods:The animal model was made by laser ablation of rabbit liver, and then shear wave dispersion imaging and strain elastography imaging were performed on the ablation area at 3 d, 7 d, and 14 d after ablation. The shear wave dispersion values, elastic value and strain ratio measured by shear wave elastography, shear wave dispersion and strain elastography in different regions such as central necrotic tissue, surrounding inflammatory reaction zone and normal liver tissue after ablation were analyzed.Results:The shear wave dispersion values of inflammatory reaction zone around ablation site, necrotic tissue in the center of ablation site and normal liver tissue in rabbits were (26.07±4.55)m·s -1·kHz -1, (21.97±10.53)m·s -1·kHz -1and (15.45±3.94)m·s -1·kHz -1, respectively, the differences were statistically significant (all P<0.05). Compared with the three time points of 3 d, 7 d and 14 d after ablation, the shear wave dispersion value of the inflammatory zone was the highest on the 7th day after ablation ( P<0.05), while the elastic value and strain ratio in this region did not change significantly among these three time points ( P>0.05). Conclusions:Shear wave dispersion imaging can simultaneously measure tissue elasticity and viscosity, which has certain application value in identifying the inflammatory reaction zone around the ablation site in rabbit liver.

Objective:To investigate the regulatory effect of bio-strength electric field (EF) on the motility and CD9 expression of human epidermal cell line HaCaT and mouse epidermal cells.Methods:The experimental research method was used. Human immortal epidermal cell line HaCaT cells in logarithmic growth phase and primary epidermal cells isolated from 16 BALB/c mice (no matter male or female) aged 1-3 days were used for experiments. HaCaT cells were divided into EF group treated for 3 h at the EF intensity of 200 mV/mm and sham EF group with simulated treatment. The cell migration (direction, displacement velocity, and trajectory velocity, with 46 samples in EF group and 34 samples in sham EF group) and arrangement were observed in the living cell workstation, and the distribution and expression of CD9 protein were detected by immunofluorescence method. Both HaCaT cells and mouse epidermal cells were divided into sham EF group (simulated treatment) and EF groups treated respectively for 3 h at the corresponding EF intensity of 50, 100, 200, and 400 mV/mm. Both HaCaT cells and mouse epidermal cells were divided into blank control group without any treatment, and 1 h group, 3 h group, and 6 h group treated with EF at the intensity of 200 mV/mm for corresponding time respectively. The expression of CD9 protein was detected by Western blotting ( n=3). Data were statistically analyzed with Mann-Whitney U test, one-way analysis of variance, independent sample t test and least significant difference test. Results:Within 3 hours of treatment, HaCaT cells in EF group tended to move towards the negative electrode obviously, while HaCaT cells in sham EF group moved randomly around the origin; compared with those of sham EF group, the directivity of HaCaT cells in EF group was significantly enhanced, and the displacement velocity and trajectory velocity were significantly increased ( Z=-3.975, -6.052, -6.299, P<0.01). After 3 hours of treatment, the long axis of HaCaT cells in EF group was perpendicular to the direction of EF, while HaCaT cells in sham EF group arranged randomly. After 3 hours of treatment, the expression of CD9 protein in HaCaT cells in EF group was significantly down-regulated compared with that of sham EF group ( t=4.527, P<0.01), although both expressed on cytomembrane. After 3 hours of treatment, the expression of CD9 protein in HaCaT cells and mouse epidermal cells in sham EF group, 50 mV/mm group, 100 mV/mm group, 200 mV/mm group, and 400 mV/mm group were 0.332±0.021, 0.283±0.032, 0.254±0.020, 0.231±0.041, 0.212±0.031 and 0.565±0.021, 0.453±0.022, 0.389±0.020, 0.338±0.021, 0.233±0.011, respectively. For both types of cells, compared with that of sham EF group, the expression of CD9 protein in cells was significantly decreased in the four groups of EF treatment ( P<0.01); compared with that of 50 mV/mm group, the expression of CD9 protein in cells was significantly decreased in the other three groups of EF treatment ( P<0.01); compared with that of 100 mV/mm group, the expression of CD9 protein in cells was significantly decreased in 200 mV/mm group and 400 mV/mm group ( P<0.01); compared with that of 200 mV/mm group, the expression of CD9 protein in cells was significantly decreased in 400 mV/mm group ( P<0.01). The expression levels of CD9 protein in HaCaT cells and mouse epidermal cells in blank control group, 1 h group, 3 h group, and 6 h group were 0.962±0.031, 0.784±0.020, 0.531±0.021, 0.409±0.011 and 0.963±0.031, 0.872±0.031, 0.778±0.040, 0.591±0.041, respectively. For both types of cells, compared with that of blank control group, the expression of CD9 protein in cells was significantly decreased in 1 h group, 3 h group, and 6 h group ( P<0.01); compared with that of 1 h group, the expression of CD9 protein in cells was significantly decreased in 3 h group and 6 h group ( P<0.05 or P<0.01); compared with that of 3 h group, the expression of CD9 protein in cells was significantly decreased in 6 h group ( P<0.01). Conclusions:The bio-strength intensity EF can induce the directional migration and arrangement of HaCaT cells and down-regulate the expression of CD9 in HaCaT cells and mouse epidermal cells in a time-dependent and intensity-dependent manner.

Objective To explore the clinical value of virtual touch tissue quantification (VTQ) technique in the diagnosis of acute rejection of transplant kidney at different stages. Methods Clinical data of 170 renal transplant recipients were retrospectively analyzed. According to the time of VTQ examination and the occurrence of acute rejection after renal transplantation, the recipients within 4 weeks and after 4 weeks post-renal transplantation were assigned into the normal renal function group (n=41, 51) and acute rejection group (n=22, 56). Clinical ultrasound parameters at different stages after renal transplantation were compared between two groups. The diagnostic value of ultrasound parameters in acute rejection at different stages after renal transplantation was evaluated. Results Within 4 weeks post-renal transplantation, the resistance index (RI) and shear wave velocity (SWV) in the acute rejection group were significantly higher than those in the normal renal function group (both P < 0.001). After 4 weeks post-renal transplantation, the SWV in the acute rejection group was significantly higher than that in the normal renal function group (P < 0.001). The area under curve (AUC) of RI and SWV in the diagnosis of acute rejection were 0.729 and 0.803 respectively within 4 weeks post-renal transplantation, which were 0.478 and 0.794 respectively after 4 weeks post-renal transplantation. The diagnostic value of SWV was higher than RI (P < 0.05). The cutoff value of SWV in the diagnosis of acute rejection within 4 weeks post-renal transplantation was considerably higher than that after 4 weeks post-renal transplantation. Conclusions VTQ technique can effectively assist in diagnosing acute rejection of transplant kidney at different stages.

Objective:To investigate the regulation effect of biological intensity electric field (EF) on the motility and CD9 expression of human epidermal cell line HaCaT and mouse epidermal cells.Methods:The experimental research method was used. Human epidermal cell line HaCaT cells in logarithmic growth phase and primary mouse epidermal cells isolated from 16 BALB/c mice aged 1-3 days were used for the experiment. HaCaT cells were divided into EF group treated with EF in the intensity of 200 mV/mm and sham EF group treated with simulated operation. The cell migration (displacement velocity, trajectory velocity, and direction, with 46 samples in EF group and 34 samples in sham EF group) and arrangement were observed in the living cell workstation, and the distribution and expression of CD9 protein were detected by immunofluorescence method. Both HaCaT cells and mouse epidermal cells were divided into sham EF group (simulated operation) and 50 mV/mm group, 100 mV/mm group, 200 mV/mm group and 400 mV/mm group treated with EF in the corresponding intensity respectively. Both HaCaT cells and mouse epidermal cells were divided into blank control group without any treatment and 1 h group, 3 h group and 6 h group treated with EF in the intensity of 200 mV/mm for corresponding time respectively. The expression of CD9 protein was detected by Western blotting (n=3). Data were statistically analyzed with Mann-Whitney U test, one-way analysis of variance, t test and least significant difference test. Results:Within 3 hours of treatment, HaCaT cells in EF group tended to move towards the negative electrode obviously, while HaCaT cells in sham EF group moved randomly around the origin; compared with those of sham EF group, the directivity of HaCaT cells in EF group was significantly enhanced, and the displacement velocity and trajectory velocity were significantly increased (Z=-3.975, -6.052, -6.299, P<0.01). After 3 hours of treatment, the long axis of HaCaT cells in EF group was perpendicular to the direction of EF, while HaCaT cells in sham EF group arranged randomly. After 3 hours of treatment, the expression of CD9 protein in HaCaT cells in EF group was significantly down-regulated compared with sham EF group (t=4.527, P<0.01), although both expressed on cytomembrane. After 3 hours of treatment, the expression of CD9 protein in HaCaT cells and mouse epidermal cells in sham EF group, 50 mV/mm group, 100 mV/mm group, 200 mV/mm group and 400 mV/mm group were 0.332±0.021, 0.283±0.032, 0.254±0.020, 0.231±0.041, 0.212±0.031 and 0.565±0.021, 0.453±0.022, 0.389±0.020, 0.338±0.021, 0.233±0.011, respectively. For both types of cells, compared with that of sham EF group, the expression of CD9 protein in cells was significantly decreased in the four groups of EF treatment (P<0.01); compared with that of 50 mV/mm group, the expression of CD9 protein in cells was significantly decreased in the other three groups of EF treatment (P<0.01); compared with that of 100 mV/mm group, the expression of CD9 protein in cells was significantly decreased in 200 mV/mm group and 400 mV/mm group (P<0.01); compared with that of 200 mV/mm group, the expression of CD9 protein in cells was significantly decreased in 400 mV/mm group (P<0.01). The expression levels of CD9 protein in HaCaT cells and mouse epidermal cells in blank control group, 1 h group, 3 h group and 6 h group were 0.962±0.031, 0.784±0.020, 0.531±0.021, 0.409±0.011 and 0.963±0.031, 0.872±0.031, 0.778±0.040, 0.591±0.041, respectively. For both types of cells, compared with that of blank control group, the expression of CD9 protein in cells was significantly decreased in 1 h group, 3 h group, and 6 h group (P<0.01); compared with that of 1 h group, the expression of CD9 protein in cells was significantly decreased in 3 h group and 6 h group (P<0.05 or P<0.01); compared with that of 3 h group, the expression of CD9 protein in cells was significantly decreased in 6 h group (P<0.01).Conclusions:The biological intensity EF can induce the directional migration and arrangement of HaCaT cells and down regulate the expression of CD9 in HaCaT cells and mouse epidermal cells in a time-dependent and intensity-dependent manner.

Objective To explore the characteristics and differences of micro-perfusion between patients after transplant kidney with stable renal function,acute rejection and chronic rejection by contrast enhanced ultrasound (CEUS) quantifying.Methods Thirty-three patients with stable renal function,27 patients with acute rejection and 14 patients with chronic rejection were enrolled.The perfusion parameters of region of interest in renal cortex and medulla were obtained by CEUS offline data quantitative analysis software.The perfusion parameters in stable renal function group were compared with those in acute rejection and chronic rejection groups;furthermore,the value of color Doppler and CEUS in the diagnosis of chronic rejection was explored and compared.Results As for resistance index RI on color Doppler,it made no statistical difference among three groups (P＞0.05).The perfusion parameters derived from CEUS quantitative analysis and Color Doppler parameter resistance index (RI) were not statistically different among renal function stabilization,acute rejection and chronic rejection groups (P＞0.05);as compared with stable renal function group,there were marked reductions in peak intensity of cortex (PIc),peak intensity of medulla (PIm),ascending slope of cortex (a3c),ascending slope of medulla (a3m) and area under the curve of cortex (AUCc) in chronic rejection group.And mean transit time of cortex (MTTc) and mean transit time of medulla (MTTm) became significantly prolonged (P＜ 0.05).Except for a3m,PIc and PIm were not significantly different between stable renal function and acute rejection groups (P＜ 0.05).As compared with acute rejection group,MTTc and MTTm were significantly prolonged in chronic rejection group while AUCm and PIm declined markedly (P＜0.05).When PIm＜26.7dB,the diagnostic efficiency of chronic rejection was the highest and the sensitivity and specificity were 85.7％ and 72.7％ respectively.Conclusions As compared with color Doppler,CEUS quantitative parameters based on S-G filter theory can evaluate the micro-perfusion of transplant kidney more precisely and may provide diagnostic clue for chronic rejection.

English for medical laboratory is an instrumental course,which aims to develop students'competency in reading English literature,writing English scientific papers and conducting international academic exchanges in English.With the continuous expansion and deepening of international exchange and cooperation in laboratory medicine and the demands for training international talents in higher education in China,higher requirements have been put forward for the teaching quality of this course.According to the post competency requirements for professionals of medical laboratory,this paper mainly discusses the teaching mode of English for medical laboratory from the aspectsof educational concept,teaching material construction,teaching mode,assessment mechanism and teachers,hoping to play an active role in the teaching reform of English for medical laboratory at the undergraduate level.