Objective To explore the professional identity of medical students with long education periods and its influencing factors.Methods Survey on professional identity was conducted through self-designed questionnaire among 665 medical students with long education periods of every grade.Single factor analysis of variance and t test were applied to do statistical analysis.Results There were significantly statistical differences in influencing factors of professional identity among every grade of long periodical medical students (P ＜ 0.05).There were significant statistical differences among influencing factors of sex,educational background of parents and residing(P ＜ 0.05).Conclusions Because of characteristics of medical education and psychological changes of students,professional identity of students shows a first decline and then an increase.Personal and environmental factors exert influences on professional identity at varying degrees.

Objective To construct adenovirus vector containing firefly luciferase reporter gene (AdLuc) and infect bone marrow mesenchymal stem cells (BMSC),then to take bioluminescence imaging in vitro and in vivo for identification.Methods The luciferase gene was amplified with PCR from psiCHECK-2 plasmid and cloned into the adenoviral shuttle vector (pShuttle-CMV).It was confirmed by Nhe Ⅰ/Xba Ⅰ digestion and sequencing.PShuttle-CMV-Luc and backbone vector (pAdeno) were homologous recombined.Then the recombinant plasmid was packaged in HEK293 cells and the virus titer was detected.The BMSC were infected by the recombinant adenovirus.The bioluminescence imaging in vitro was performed to determine the best multiplicity of infection (MOI),and the relationship between bioluminescence intensity and MOI was analyzed by curve fitting regression analysis.Viability was evaluated via Trypan blue staining.The transfected BMSC (l× 106) were implanted into the muscles of forelimb of SD rats,and then tracked by bioluminescence imaging in vivo.Cell viability was compared using two-way repeated measures analysis of variance between groups.Results Enzyme digestion and sequence analysis indicated that Ad-Luc was successfully constructed.The virus titer was 1 × 1010 plaque forming unit (PFU)/ml.The bioluminescence detection in vitro showed that Ad-Luc could infect BMSC high efficiently to express luciferase and the best MOI was 50.The bioluminescence intensity enhanced with increase of MOI (R2 =0.98).No statistically significant difference was found in cell viability between transfected and untransfected BMSC at 1,3,5,7 d.The cell survival rates were (92.5±2.3)％ vs (94.1±1.8)％,(91.4±0.9)％ vs (92.7±2.0)％,(92.1±1.6)％ vs (93.3± 2.4) ％,(91.9 ± 1.5) ％ vs (93.0 ± 3.1) ％,respectively (F =4.38,P ＞ 0.05).The bioluminescence imaging in vivo showed that BMSC survived 1,3,7 d after implantation.However,bioluminescence signal decreased gradually over time.Conclusion It is feasible to apply the optical reporter gene imaging for tracing transplanted stem cells in vitro and in vivo due to the effective transformation of luciferase reporter gene into BMSC by adenovirus vector.

Objective To predict the spatial distribution of Himalayan marmot using geographic information system (GIS) and Genetic Algorithm for Rule-set Production (GARP) model based on the monitoring data of Himalayan marmot in Qinghai Province.Methods Based on the data of routine monitoring and field survey by Global Position System (GPS) of Himalayan marmot,the position data was processed by spatial mapping using ArcGIS software.Ecological environment variables related to Himalayan marmot including terrain,slope,temperature,precipitation,vegetation,land use and other related variables were extracted and analyzed.The prediction model of Himalayan marmot distribution was constructed based on GARP model and ArcGIS software,and the spatial distribution mapping and analysis were carried out.Results Totally 198 points of Himalayan marmot were obtained by combining the recovery position with GPS information.The average model error of omission was 1.998 through the GARP modeling,while the optimal 100 model were highly statistically significant (all x2 ＞ 163.03,all P ＜ 0.01).The spatial distribution of predicted probability was divided into three grades including less than ＜ 40％,40％-＜ 80％ and 80％-100％ using ArcGIS,and the area with the prediction probability of 80％-100％ was the most suitable distribution area of Himalayan marmot.Conclusions The spatial distribution of plague host animal is predicted successfully using GIS and GARP ecological niche model.The result is more accurate compared to the statistic area by administrative region,which can provide important reference for plague prevention and control.

Objective:To fabricate and to study the surface morphology and biological safety of a novel coating on microarc-oxidized titanium.Methods:The novel functional coating was fabricated by cross-linking the double-layer nanoparticles loading rhBMP-2 and SDF-1 with gelatin on microarc-oxidation coating on titanium implant surface.The surface topography was observed and optimized,and the biological safety of the novel coating was primarily evaluated by cell toxicity test,oral mucosa stimulation test and hemolysis test in vitro.Results:The novel functional coating possesses excellent morphology.The coating showed the cytotoxicity of score 1 and no mucous membrane irritation,the hemolytic rate of the coating was 4.6％.Conclusion:The coating possesses good morphology and biological safety.

Objective:To compare the choriocapillaris flow density and choroidal vessel volume (CVV) of acute and chronic central serous chorioretinopathy (CSC).Methods:A cross-sectional observational clinical study. A total of 64 eyes of 64 patients (CSC group) diagnosed with CSC at Department of Ophthalmology of West China Hospital of Sichuan University from May 2019 to October 2020, and a total of 64 eyes of 64 age and gender matched healthy volunteers (control group) during the same period were included in this study. In the CSC group, there were 34 patients with acute CSC (acute CSC group) and 30 patients with chronic CSC (chronic CSC group). There was no significant difference in age ( t=-0.041) and sex composition ratio ( χ2=0.191) between CSC group and control group ( P>0.05). There were statistically significant differences in age ( t=-1.872) and sex composition ratio ( χ2=8.778) between acute CSC group and chronic CSC group( P<0.05). Swept source optical coherence tomography angiography (SS-OCTA) was performed using VG200D. The scanning mode was 512×512 and scannig range was 12 mm × 12 mm. The choriocapillaris flow density of the 3 mm, 6 mm, 12 mm circular area and 1-3 mm ring, 3-6 mm ring, and 6-12 mm ring, and the CVV of the of the 3 mm, 6 mm, 12 mm circular area was automatically generated by the built-in software (v1.28.6). The age, choriocapillaris flow density and CVV were compared between two groups using independent sample t test. Results:Compared with the control group, the choriocapillaris flow density decreased in the CSC group, and there were statistically significant differences in the 3 mm, 6 mm circular area ( t=-7.210, -4.040; P<0.001). There were statistically significant differences between CSC group and control group in the 3 mm, 6 mm, 12 mm circular area ( t=1.460, 12.270, 11.250; P<0.05). Compared with the acute CSC group, the choriocapillaris flow density decreased in the chronic CSC group, and there were statistically significant differences ( P<0.05) in the 3 mm, 6 mm circular area ( t=3.230, 2.330), the total and four quadrants of 1-3 mm ring ( t=2.780, 2.060, 2.140, 2.620, 3.770), the superior quadrants of the 3-6 mm ring ( t=2.550), and the superior and temporal of 6-12 mm ring ( t=3.070, 2.610). There was no significant difference of CVV in the 3 mm, 6 mm and 12 mm circular area between the acute CSC group and the chronic CSC group ( t=0.250, 0.070, -0.110; P>0.05). Conclusion:Compared with acute CSC, chronic CSC exhibits significant decreased choriocapillaris flow density and no change in CVV.

Objective:To explore the clinical application of NanoString fluorescent barcode technology in the molecular subtyping of diffuse large B-cell lymphoma (DLBCL), and to analyze the correlation between the cell-of-origin subtype and prognosis of patients.Methods:The tumor tissue samples of 12 patients with DLBCL at the Third People's Hospital of Datong of Shanxi Province and 8 patients with DLBCL at Peking University, Health Science Center between January 2014 and December 2019 were collected. According to Hans algorithm, all patients were divided into 1 case of germinal center-derived B-cell (GCB) type and 19 cases of non-GCB type. NanoString platform was used to analyze the expression level differences of 15 genes-related to Lymph2Cx molecular subtyping of all samples at mRNA level. Hierarchical clustering was used to subgroup 20 DLBCL cases and to contrast the prognosis in different subgroups according to the subtyping.Results:NanoString fluorescent barcode technology was used to detect samples of 20 DLBCL cases and hierarchical clustering analysis was performed, and then subtyping results showed that 11 cases were GCB-like type and 9 cases were activated B cell (ABC)-like type. Based on Hans algorithm, 10 GCB-like cases were non-GCB type. According to the survival analysis, GCB-like group had a better overall survival compared with that in ABC-like group ( P=0.019). Conclusion:NanoString fluorescent barcode technology can be successfully applied to the cell-of-origin subtyping of DLBCL, and the molecular subtyping strategy can effectively predict the prognosis of patients.

Objective To observe the clinical effects of external application of Chinese medicine ion introduction through acupiont in the prevention and treatment of hyperamylasemia and pancreatitis following endoscopic retrograde cholangio pancreatography (ERCP). Methods Three hundred subjects were divided into treatment group and control group randomly, and treated with routine therapy after surgery, moreover, treatment group was treated with external application of Chinese medicine ion introduction through acupiont. The incidence of hyperamylasemia and pancreatitis, the time of serum amylase returned to normal in patients with hyperamylasemia and pancreatitis was observed, and the abdominal pain after ERCP was scored. Results Excluding 17 cases according to the exclusion criteria, the treatment group included 142 cases and the control group included 141 cases. The hyperamylasemia and pancreatitis happened less frequently in the treatment group than in control group, but there was no significant difference (P>0.05). The time of serum amylase returned to normal in patients with pancreatitis was (4.25±0.95)d in treatment group and (5.28±1.11)d in control group, with no significant difference (P>0.05). The time of serum amylase returned to normal in patients with hyperamylasemia was (2.88 ± 0.78)d in treatment group and (3.81±1.62)d in control group, showed a significant difference (P<0.05). The score of abdominal pain was 0.95±1.04 in treatment group and 1.21±1.12 in control group, showed a significant difference (P<0.05). Conclusion External application of Chinese medicine ion introduction through acupoint can promote the recovery of the patients postoperative ERCP combined with hyperamylasemia or pancreatitis, and can better alleviate abdominal pain.

27 rabbits were divided into normal group(n = 4),control group (n = 5), silybin group (n = 6), hyperbaric oxygen (HBO) group (n = 6), and HBO combined with silybin group (n = 6). Circulation of hindlimb was interrupted completely for 6 h and reperfused for 1 h. Malondialdehyde (MDA) and superoxide dismutase(SOD) in plasma from ischemic-reperfused injured limb were measured. Adenosine triphosphate (ATP) and creatine phosphate (CP) in samples taken from anterior tibial muscle were determined. Ultrastructural changes of injured muscle were observed. The results showed that HBO combined with silybin treatment had a favourable effect on ischemic and reperfused injured limb muscle with reduction of the lipid peroxidated injury, increase of the SOD activity and the high energy phosphate compounds (ATP and CP), and a promoting recovery of injured muscle cells. HBO and silybin had a synergistic action. It suggests that HBO combined with silybin is an effective method for treatment of ischemic and reperfused injured limb.

Objective To evaluate the clinical efficacy and safety of sibutramine (Reductile )in Chinese obese patients. Methods Obese adults (BMI 27～45 kg/m 2) in six research centers received sibutamine 10 mg or placebo one tablet each day with a controlled-energy diet for 24 weeks by randomized, double-blinded, placebo-controlled study. Results For intent-to-treat analysis, 125 sibutramine-treated subjects and 126 placebo-treated subjects were evaluated. After 24 weeks, sibutramine-treated patients lost more weight (6.52?3.95)kg than placebo-treated patients (3.18?3.59)kg(P

Objective:To evaluate the fit of titanium alloy removable partial denture framework fabricated by selective laser melting(SLM) technique.Methods:7 Kennedy Ⅲ Ti-6Al-4V removable titanium alloy partial denture frameworks were fabricated by SLM technology.An optical scanner was used to scan the gypsum model adhered with the silicone rubber film obtained by the impression method before and after removal of the film.Geomagic Qualify 2013 software was used to analyze the gap between the model and the tissue surface of the major connector of the framework,the fit of the frame work was evaluated.Results:The overall 3D deviation between the titanium alloy frameworks and the gypsum model was (0.221 9±0.07) mm.Conclusion:The fit of the titanium alloy removable partial denture framework made by SLM technology can basically met the clinical requirements.