Objective:To explore the distinctions between different educational levels: stability of learning state, views on and demand for online courses, and further investigate the influencing factors.Methods:A self-designed questionnaire with good reliability and validity was conducted, and all the students in a military medical university were selected by cluster sampling method, and the data were collected by issuing a network questionnaire. SPSS 26.0 was used for data processing.Results:Undergraduates were different from graduates and doctoral students in stability of learning state, the period of home study: doctoral students (2.41±1.30) h < graduates (2.10±1.17) h and undergraduates (2.15±0.99) h; the frequency of using online courses: undergraduates (4.18±1.10) times > graduates (3.29±1.16) times and doctoral students (3.29±0.98) times. In terms of views on online courses, necessity: undergraduates (4.14± 1.01) > graduates (3.93±1.05) and doctoral students (3.78±1.03); familiarity: undergraduates (3.42 ± 0.91) > graduates (3.27±0.97); adaptability: undergraduates (3.79±0.91) > graduates (3.58±0.94) and doctoral students (3.63±0.97); likability: undergraduates (3.36±1.04) > undergraduates (3.25±0.96) and doctoral students (3.17 ± 1.01); teaching effect: undergraduates (2.80±1.04) > graduates (2.67±1.01) and doctoral students (2.61±1.03). In terms of demand for online courses, ideal number: undergraduates (2.52±1.27) > graduates (2.11±1.21) and doctoral students (2.01±1.25); class style: undergraduates (1.77±0.94) > graduates (2.00±0.92) and doctoral students (2.04±1.83). There were statistically significant differences between undergraduates and postgraduates in all dimensions ( P<0.01 or P<0.05). Conclusion:Undergraduates may be more susceptible to academic environment than graduates and doctoral students, showing that the learning stability of undergraduates is the relatively the worst. Undergraduates most recognize online courses, and different educational levels have different demands for online courses.

Objective To investigate the expression of HERV-HLTR-associating protein 2(HHLA2).in hepatocellular carcinoma(HCC) tissue and its relationship with different pathological grades,clinical stages,liver function and serum AFP level.Methods The positive rate of HHLA2 expression in 150 cases of paraffin-embedded HCC tissues was detected by immunohistochemistry.Ten cases of normal liver tissue specimens from health donors served as the normal control.The differences of HHLA2 expression in HCC tissues were compared among different pathological grades,clinical stage,liver function grades and serum AFP levels.Results The positive expression rate of HHLA2 in HCC tissue was significantly higher than that in normal control (P＜0.05).The positive rate of HHLA2 expression in low differentiated HCC tissue was highest.The positive rate of HHLA2 expression in the low differentiation and moderate differentiation HCC groups was significantly higher than that in the high differentiation group (P＜0.05).The positive expression rate in the patients with Barcelona stage C and D was significantly higher than that in the patients with the stage A and B(P＜0.05).The positive expression rate in the patients with Child-Pugh stage A was significantly higher than that in the patients with stage B and C(P＜0.01).While the HHLA2 expression rate had no statistically significant difference among different ages and different serum AFP levels(P＞0.05).Conclusion The positive expression rate of HHLA2 in cancer tissues of HCC patients is significantly increased.HHLA2 might play a certain role in the occurrence,development and metastasis of HCC.

Objective Studies have shown that problem based learning (PBL) can improve the students' ability of autonomous learning.However,it is unclear whether students' autonomous learning ability will affect students' evaluation in PBL teaching.This study took medical psychology course as an example to explore the influence of medical students' autonomous learning ability on PBL teaching effect.Methods 43 8-year program medical students of Grade 2010 and 2011 were enrolled in this study.Scale was used to assess medical students' autonomous learning ability before the start of the PBL teaching.Self made questionnaire was used to survey the students' evaluation in PBL teaching.Linear correlation analysis was used to detect the relationship between medical students' autonomous learning ability and students' evaluation in PBL teaching and their examination results.Results Medical students' autonomous leaming ability is significantly positively correlated to the students' evaluation of PBL teaching (P＜0.05).The correlation coefficient between learning motivation and "PBL enhanced learning interest" or "PBL enhanced information utilization ability" was high (r=0.507 and 0.536,respectively).It showed that students with stronger autonomous learning ability had more positive evaluation of PBL teaching.The students' learning motivation was also positively correlated to the test score (r=0.416,P=0.006).Students with stronger learning motivation had higher test score in the final exam.Conclusion These results indicate that the relationship between the students' autonomous learning ability and PBL teaching is bidirectional.The students with more powerful ability of autonomous learning will be more active in the process of PBL teaching,and the positive experience will promote their autonomous learning ability in turn.

Objective To investigate the epidemiological characteristics of dengue fever in Shenz-hen city in 2014 and to analyze the evolutional characteristics of the epidemic dengue virus(DENV)strains in order to provide scientific guidelines for the prevention and control of dengue fever. Methods Descrip-tive epidemiological analysis was used to analyze the prevalence of dengue fever in Shenzhen city in 2014. Immunochromatography and real-time PCR were performed to detect the specific antibodies(IgM and IgG) and DENV nucleic acids in serum samples collected from suspected cases of dengue fever. Serum samples collected from the patients at early stage of dengue fever were used to infect the C6 / 36 cell line for further isolation of DENV strains. The types of isolated DENV strains were determined by using real-time PCR. E genes of the isolated DENV strains were amplified by RT-PCR and then sequenced. DNAStar and Clustslx (1. 83)softwares were used to analyze the homology between DENV strains isolated in Shenzhen and other areas. A phylogenetic tree based on the sequences of E genes of Shenzhen strains and other sequences of DENV reference strains downloaded from GenBank was constructed for further analysis. Results A total of 454 cases of dengue fever were reported in Shenzhen in 2014 with a male to female ratio of 1. 43 ∶ 1. Local patients accounted for 76. 21% and the rest 23. 79% were imported cases mainly from Southeast Asian and surrounding cities. There were 441 cases reported from September to November,accounting for 97. 14% of all reported cases. Most of the infected subjects were aged 20 to 50,accounting for 76. 73% . Of the 270 samples positive for DENV nucleic acids,strains of DENV-1,DENV-2,DENV-3 and DENV-4 accounted for 87. 41% ,8. 89% ,0. 37% and 2. 22% ,respectively. The phylogenetic tree analysis revealed that the DENV-1 strains belonged to two genotypes,which were genotypeⅠ and genotype Ⅴ. The DENV strains of genotypeⅠ were highly similar to the epidemic strain isolated in Shenzhen in 2010 and the genotype Ⅴstrains were first reported in Shenzhen. The homology analysis of the nucleotides of E genes showed that mi-nor differences in the nucleotide sequences were found between DENV-2 strains. All of the DENV-2 strains belonged to the genotype Ⅳ as indicated by the phylogenic tree. Conclusion There were 454 cases of den-gue fever(including both local and imported cases)reported in Shenzhen city in 2014,reaching an all-time high. DENV-1 was the predominant pathogen in combination with an increased infection of DENV-2. This study indicated that the prevalent DENV strains might be imported from Southeast countries and neighboring cities. Further researches should be conducted to analyze whether dengue fever is endemic in Shenzhen City.

According to the course characteristics and teaching outline of medical psychology,problem-based learning (PBL) case about somatoform disorders was compiled based on a typical clinical real case.The PBL case covered a wide range of topics such as basic medicine,clinical medicine and medical psychology.Just as clinical treatment process,teachers gave information and put forward the corresponding questions in successive steps.By self-study and group discussion,students learned knowledge about anxiety,somatoform disorders,therapeutic relationship,sociocultural factors and individual personality.The course survey showed that PBL teaching was appreciated by medical students.The PBL model can improve learning interest and self-study ability,promote the connection of different subjects and combine theory and practice.The PBL model is useful for improving the quality of medical psychology teaching.

OBJECTIVE: To evaluate the curative effect and safety of endoscopic full-thickness resection (EFR) in the treatment of gastric tumor originated from the muscularis propria.
 METHODS: Clinical data were collected from 34 patients, who underwent EFR of gastric tumor originated from muscularis propria, to observe the resection rate and complications from November 2012 to August 2014.
 RESULTS: Of the 34 patients, 15 were male, 19 were female, with the age of 38.3-70.6 (52.3±4.3) years old. The lesions of 25 patients located in the fundus of stomach and the rest was in the gastric body. EFR was successfully performed in the 34 patients with no need for surgery. The complete resection rate was 100%. Lesion diameter ranged from 1.0 to 5.0 (2.8±1.2) centimeters. The operation time was 50-100 (76.5±18.2) min. Patients with pneumoperitoneum were relieved after abdominal puncture exhaust, without post-operation bleeding and perforation. The hospitalization duration was 3-5 (3.6±0.8) days. Except 1 case, the remaining 33 cases were spindle cell tumors, consistent with the results of immunohistochemistry. The risk for two lesions with 4.5 cm and 5.0 cm was moderate. The risk of invasion was low or very low in the remaining 31 cases. Among them, 2 stromal tumors near the cardia showed a differentiation tendency toward smooth muscle. No lesion residual or recurrence happened during the follow-up period (range 5-23 months) in 34 cases. 
 CONCLUSION EFR is a safe and effective method for gastric tumor originated from muscularis propria.
Adult ; Aged ; Cardia ; Female ; Gastric Fundus ; Gastric Mucosa ; Gastroscopy ; Humans ; Immunohistochemistry ; Length of Stay ; Male ; Middle Aged ; Operative Time ; Stomach Neoplasms

OBJECTIVE: To evaluate the efficacy and safety of peroral endoscopic myotomy (POEM) for achalasia cardia (AC).
 METHODS: A total of 62 patients with AC were enrolled and treated with POEM in the Third Xiangya Hospital, Central South University from April 2012 to October 2014. The symptoms and complications were retrospectively analyzed.
 RESULTS: The ages of patients, including 32 males and 30 females, were 14-68 (43.2±5.6) years old. Eckardt scores were 4-6 or ≥7 for 25 patients or 37 patients (including 20 patients were at a score of 12). Thirteen patients suffered balloon expansion for 2-3 times. Sixty-one patients had completed POEM treatment, 1 patient were given Heller surgery instead of POEM because of extensive submucosal adhesion during POEM. The operative time for POEM was (60.8±15.1) min. Fourteen patients had mild subcutaneous emphysema. Among them, 5 suffered pneumoperitoneum and felt better after abdominal puncture exhaust; 2 patients suffered bronchospasm hypoxemia and were relieved after treatment by positive pressure oxygen for 1 h. The hospital stay was (4.3±1.2) d. The postoperative follow-up period was (11.4±5.4) months. Swallowing obstruction, vomiting and chest pain in patients was relieved at different degrees. The treatment effective rate was 100%. 
 CONCLUSION POEM is a safe, effective and minimally invasive approach for AC.
Adolescent ; Adult ; Aged ; Cardia ; physiopathology ; Endoscopy ; adverse effects ; methods ; Esophageal Achalasia ; surgery ; Esophageal Sphincter, Lower ; physiopathology ; Female ; Humans ; Length of Stay ; Male ; Middle Aged ; Operative Time ; Postoperative Period ; Retrospective Studies ; Treatment Outcome ; Young Adult

Objective Recent studies have indicated that early brain injury is the leading cause of death in patients with subarachnoid hemorrhage ( SAH) .Our study investigated the role of aminoguanidine ( AG) in early brain injury after SAH . Methods Sixty-eight male SD rats were equally randomized into four groups of equal number :control, sham, SAH, and AG.The animals in the sham group were injected with isotonic saline solution , while those of the latter two groups with femoral artery blood ( FAB) and FAB+AG, respectively, into the pre-chiasmatic cistern to induce SAH. At 24 hours after modeling , all the rats were killed for HE staining , obtainment of behavioral neurological assessment ( BNA ) scores by Garcia, measurement of the apoptosis of neurons by TUNEL , and de-termination of the expressions of the iNOS and NSE proteins by West-ern blot. Results The results of HE staining showed the presence of more red blood cells in the subarachnoid cavity of the rats in the SAH group, with a significantly decreased BNA score ( 14.47 ± 0.62) as compared with those in the control (17.94 ±0.24), sham (17.59 ±0.51), and AG group (15.71 ±0.47) (P<0.05). The rate of positive cells was remarkably higher in the SAH group ([42.38 ±2.38]%) than in the control ([6.35 ±0.94]%), sham ([6.85 ±0.69]%), and AG group ([30.48 ±2.89]%) ( P<0.01), with significant differences among the latter three groups (P<0.05).The expressions of iNOS and NSE were markedly higher in the SAH group ([3.86 ±0.07] and [1.59 ±0.06]) than in the control (0 and[0.35 ±0.09]), sham ([2.96 ±0.34] and [0.38 ±0.08]), and AG group ([3.41 ±0.04] and [0.70 ±0.12]) ( P<0.05).Both the expression levels of iNOS and NSE were positively correlated with the rate of positive cells (r=0 .879 and 0.935, P<0.01). Conclusion AG can alleviate early brain injury after SAH in SD rats by improving the neuro-ethologic function , suppressing the apoptosis of neurons , and reducing the expressions of iNOS and NSE .

BACKGROUNDSleep deprivation (SD) has been used in treatment of depression disorder, and could effectively improve the patients' depressive symptoms.The aim of the study was to explore the effects of SD on electroencephalographic (EEG) and executive function changes in patients with depression.

METHODSEighteen depression patients (DPs) and 21 healthy controls (HCs) were enrolled in the present study. The whole night polysomnography (PSG) was recorded by Neurofax-1518K (Nihon Kohden, Japan) system before and after 36 hours of SD. The level of subjects' depression state was assessed by Visual Analogue Scale (VAS), and the executive function was assessed by Wisconsin Card Sorting Test (WCST).

RESULTSSignificantly decreased sleep latency (SL; before SD: (31.8 ± 11.1) minutes, after SD: (8.8 ± 5.2) minutes, P < 0.01) and REM sleep latency (RL; before SD: (79.8 ± 13.5) minutes, after SD: (62.9 ± 10.2) minutes, P < 0.01) were found after SD PSG in depression patients. Decreased Stage 1 (S1; before SD: (11.7 ± 2.9)%, after SD: (7.3 ± 1.1)%, P < 0.01) and Stage 2 (S2, before SD: (53.8 ± 15.5)%, after SD: (42.3 ± 14.7)%, P < 0.05) of non-rapid eye movement (NREM) sleep, and increased Stage 3 (S3, before SD: (11.8 ± 5.5)%, after SD: (23.6 ± 5.8)%, P < 0.01) and Stage 4 (S4, before SD: (8.8 ± 3.3)%, after SD: (27.4 ± 4.8)%, P < 0.01) NREM sleep were also found. After SD, the depression level in patients decreased from 6.7 ± 2.1 to 2.9 ± 0.7 (P < 0.01). In WCST, the patients showed significantly decreased Response errors (Re, before SD: 22.3 ± 2.4, after SD: 18.3 ± 2.7, P < 0.01) and Response preservative errors (Rpe, before SD: 11.6 ± 3.6, after SD: 9.3 ± 2.9, P < 0.05). Depression patients' RE (t = 2.17, P < 0.05) and Rpe (t = 2.96, P < 0.01) also decreased significantly compared to healthy controls.

CONCLUSIONSD can improve depression symptom and executive function in depression patients.

Adult ; Depression ; physiopathology ; Female ; Humans ; Male ; Middle Aged ; Polysomnography ; methods ; Sleep Deprivation ; physiopathology

BACKGROUNDNicotine may improve schizophrenia patient's cognitive deficit symptoms. This study was to explore the chronic effects of smoking on prepulse inhibition of the startle reflex (PPI) and P50 in the patients with first-episode schizophrenia (FES).

METHODSThe event-related potentials (ERP) recording and analysis instrument made by Brain Products, Germany, was used to detect PPI and P50 in 49 male FES patients (FES group, n = 21 for smokers and n = 28 for non-smokers) and 43 normal male controls (control group, n = 19 for smokers and n = 24 for non-smokers).

RESULTSCompared with normal controls, the FES group had prolonged PPI latency when elicited by single stronger stimulus (P < 0.05); the FES group had prolonged PPI latency and increased PPI amplitude (P < 0.05, 0.01) when elicited by weak and strong stimuli. The FES group had lower PPI inhibition rate than normal controls (P < 0.05). Compared with normal controls, the FES group had increased P50-S2 amplitude and increased amplitude ratio S2/S1 (both P <0.05). In the control group, the smokers had a tendency of increase in P50-S2 amplitude (P > 0.05) and shorter P50-S2 latency (P < 0.05) than the non-smokers. The smokers had higher PPI amplitude than the non-smokers (P < 0.05). In the FES group, the smokers had higher P50-S1 amplitude, shorter P50-S2 latency, and higher amplitude ratio S2/S1 than the non-smokers (P < 0.05, 0.01). The smokers had higher PPI amplitude than the non-smokers (P < 0.05).

CONCLUSIONSThere is obvious PPI and P50 deficits in schizophrenic patients. However, these deficits are relatively preserved in the smokers compared with the non-smokers, which suggests that long-term smoking might partially improve the sensory gating in schizophrenic patients. Whether this conclusion can be deduced to female patients requires further follow-ups.

Adult ; Case-Control Studies ; Evoked Potentials ; drug effects ; physiology ; Humans ; Male ; Reflex, Startle ; physiology ; Schizophrenia ; physiopathology ; Smoking ; adverse effects ; Young Adult