A century ago the Flexner Report facilitated the process of modern medical education reform.Half a century ago,Problem-based learning initiated the student-centered medical education model.At present training medical students' competency will usher in the third reform in medical education.Over 100 years' development and in the global context of current medical education reform,China's medical education has become an important part of the world medical education.Harbin Medical University conducted an all-around reform through international cooperation and received the accreditation referenced according to global standards in medical education,which is an epitome of the medical education reform in China.

Ephedrae Radix Et Rhizoma is a traditional Chinese medicine, and the effect of antiperspirant has been recorded in books on Chinese medicines in all dynasties. By referring the relative literatures on Ephedrae Radix Et Rhizoma from home and abroad, the study progress in the chemical constituents, pharmacological actions and clinical application of Ephedrae Radix Et Rhizoma in the latest 40 years were reviewed to lay foundation for the reasonable exploitation and utilization of Ephedrae Radix Et Rhizoma.

Objective To study and evaluate mini-titanum-plates the effects applied to four limbs bone and joint fracture.Methods 132 patients in our hospital suffered from four limbs fractures treated with open reduction internal fixation of Medicon mini-plate from February 2004 to June 2013 were studied retrospectively,including 60 cases of metacarpal and phalanx fracture(93 lesions),37 cases of metatarsal and phalanx fracture(62 lesions),15 cases of radial head fracture,9 cases of scaphoid fracture,4 cases of coronoid process of ulna fracture,4 cases of patella frature,3 cases of condyles of femur.Results Clinical outcomes:hands and feet group:follow-up postoperative 8-12 months,evaluation results showed that excellent was 78cases,good was 66cases,poor was 11cases,good rate was 92.9％.group of radius head fracture:Fractures got osteal union after 6 months to 1 year.good rate was 93.3％.group of scaphoid bone fracture:Fractures got osteal healing.all cases adopt improved Mayo Evaluation Wrist Function to evaluate,good rate was 88.9％.Including 4 cases of Coronoid process of ulna fracture,4 cases of patella fracture,3 cases of femoral condylar fracture,the excellent good rates was 100％.Conclusions Metacarpal and metatarsals phalanx fracture treated with mini-plate can get reduction anatomically,control rotation,prevent malformation and keep compression,they are the ideal internal fixation material;free fragments for intra-articular fracture fixed by mini-titanum-plate and screws can get reduction precisely,be fixed satisfactory,also can choose the appropriate application.

BACKGROUND:Artificial femoral head replacement provides a new idea for the repair of unstable intertrochanteric fracture. Artificial prosthesis replacement may affect original femoral biomechanical stability and lead to a variety of adverse consequences. OBJECTIVE:To analyze the stress distribution of femoral head replacement in the treatment of unstable femoral intertrochanteric fractures with three-dimensional finite element analysis. METHODS:One male old volunteer was randomly selected from population who underwent health examination. The left femur was scanned with spiral CT, and the three-dimensional finite element models of the human femur and prosthesis were established. The three-dimensional finite element model was used to simulate the actual working conditions of human climbing stairs, and the stress distribution of the bone channels around the surface of the femur and the prosthesis was analyzed with three-dimensional finite element analysis. RESULTS AND CONCLUSION: Under normal condition, the stress of the human femur was in a consistent state. Stress changed gradualy from the proximal end to the distal end. The stress of the prosthesis was concentrated in the middle section. The prosthesis of inner stress distribution was analyzed to obtain stress distribution of prosthesis and femur cancelous bone interface. The analysis found that stress change trend was consistent. The results suggest that artificial femoral head replacement does not have a significant effect on the overal stress distribution of the human femur, and the overal stress distribution does not change, and the maximum stress region is located in the middle of the whole femur. After the reconstruction, the stress concentration of the femur is not observed.

Objective To construct a chimeric infectious clone of the fatal virulent strain SDLY 107, containing the gene fragments encoding 2A and 3B proteins of the mild virulent strain SDLY 1, and to establish a reverse genetic system platform for further investigation on virulence of enterovirus 71 strains. Methods The overlap PCR analysis was performed to obtain the gene fragments encoding 2A and 3B pro-teins of the mild virulent strain SDLY 1.The obtained gene fragments were digested and then cloned into a plasmid pMD19-T containing the full-length gene of SDLY 107 strain by using gene replacement strategy. The recombinant RNA was transfected into Vero cells for the preparation of recombinant virus particles.Sev-eral assays including the PCR, indirect immunofluorescence ( IFA) , Western blot and sequencing were per-formed for virus identification.Virus titers were measured by 50%cell culture infective dose ( CCID50 ) and plaque assay.Results The infectious clones of SDLY 107-2A-1 and SDLY 107-3B-1 chimeric virus strains were constructed successfully.Typical cytopathic effect was observed in Vero cells after viral transfection. Identification of the rescued viruses by PCR, IFA, Western blot and sequencing further confirmed the suc-cessful construction of infectious virus strains.The virus titers of SDLY 107-2A-1 and SDLY 107-3B-1 strains detected by CCID50 and plaque assay were 1.25 ×105 PFU/ml and 0.7 ×105 PFU/ml, respectively. Conclusion The chimeric viruses SDLY 107-2A-1 and SDLY 107-3B-1 were rescued successfully, causing cytopathic effects similar to those by using the parental virus strain SDLY 107.This study might pave the way for further investigation on in vitro and in vivo virulence of enterovirus 71 strains.

OBJECTIVETo investigate the effect of low-molecular-weight heparin (LMWH) combined with paclitaxel (PTX) on the invasiveness and migration of nasopharyngeal carcinoma cells and explore the molecular mechanisms.

METHODSMTT assay was used to detect the growth inhibition induced by LMWH and PTX in CNE1 and CNE2 cells. Wound healing assay and Transwell migration assay were employed to assess the effects of the drugs on the cell migration, and Transwell invasion assay was used to evaluate the cell invasiveness. The cellular expression of matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) were analyzed by Western blotting. ELISA was used to determine the expression of heparanase (HPA) in the culture medium of the cells.

RESULTSMTT assay showed an obvious suppression of CNE1 and CNE2 cell proliferation in response to LMWH and PTX treatments. Treatment with 200 U·ml LMWH combined with 0.1 µmol·L PTX for 24 h resulted in the inhibition rates of migration of 66.70% and 70.53% in CNE1 and CNE2 cells, respectively significantly higher than the rates in cells with PTX treatment alone. The combined treatment with LMWH and PTX for 24 h also caused a significantly higher inhibition rate of cell invasion than LMWH and PTX alone. LMWH enhanced the down-regulation of MMP-9 and HPA induced by PTX.

CONCLUSIONLMWH can enhance the inhibitory effect of PTX on the migration and invasion of nasopharyngeal carcinoma cells, the mechanism of which may involve the down-regulation of MMP-9 and HPA expressions.

Carcinoma ; Cell Line, Tumor ; Cell Movement ; drug effects ; Cell Proliferation ; drug effects ; Glucuronidase ; metabolism ; Heparin Lyase ; metabolism ; Heparin, Low-Molecular-Weight ; administration & dosage ; pharmacology ; Humans ; Matrix Metalloproteinase 9 ; metabolism ; Nasopharyngeal Neoplasms ; pathology ; Paclitaxel ; administration & dosage ; pharmacology ; Tissue Inhibitor of Metalloproteinase-1 ; metabolism

Objective: To investigate the effects on human peripheral blood erythrocytes of long-term occupational contact with chromate. Methods: A dynamic cohort study was conducted of chromate-exposed workers (343 cases) and non-chromate-exposed workers (73 cases) at a chromate production enterprise who were selected according to specific inclusion and exclusion criteria from 2010 to 2015. Personal information and chromate exposure information were obtained by questionnaire. A generalized estimating equation was employed to analyze the effects on human peripheral blood erythrocytes of long-term occupational contact with chromate, controlling for age, gender, smoking, alcohol consumption and body mass index. Results: The mean ages and working ages of those entering the cohort study were 36.67 ±6.78 and 38.47 ± 7.18, respectively, for the exposure group and 8.39 ± 6.02 and 12.86 ± 8.34, respectively, for the control group. The erythrocyte content [(4.73±0.46), (4.81±0.53), (4.41±0.45)]×10¹²/L in the peripheral blood in the chromate exposure group was lower than that [(4.76±0.42), (4.95±0.45), (4.47±0.39)]×10¹²/L in the control group for the years 2010, 2011, 2012 and 2014 (t values were 0.38, 1.96, 0.92 and 1.21; P values were 0.703, 0.051, 0.358 and 0.227, respectively). The correlations between the years 2010 and 2011, 2011 and 2012, 2012 and 2014, and 2014 and 2015 were 0.667, 0.464,-0.070 and 0.020, respectively (P<0.001). The RR for males and those that consumed alcohol were 0.661 (95% CI: 0.616-0.709) and 0.910 (95% CI: 0.811- 1.201), respectively. Compared with the control group, the risk of reduced erythrocyte levels in the peripheral blood was increased by 0.915 (95% CI: 0.852- 0.982) in the chromate-exposed group. Conclusions The erythrocyte content of peripheral blood was reduced after long-term exposure to chromate. Maleness and alcohol consumption were factors that increased the risk of reduced peripheral blood erythrocytes in the chromate-exposed population.

Objective:To investigate the prevalence of Mycoplasma pneumoniae ( Mp) in children undergoing physical examination. Methods:This study randomly enrolled 1 303 children at the age of 6-12 years who underwent physical examination in 2023. Their oral and pharyngeal swabs as well as venous blood samples were collected. The prevalence of Mp in these subjects was detected using isolation and culturing, nucleic acid detection and serological test. Chi-square test was used for statistical analysis. Results:Among the 1 303 children, the detection rate of Mp was 4.1% (53/1 303) by culturing, 7.3% (95/1 303) by nucleic acid detection and 13.6% (177/1 303) by serological test. Statistical analysis showed that there were significant differences in the the detection rates of Mp among children undergoing physical examination between the three methods ( P<0.05). Conclusions:The detection rate of Mp in children undergoing physical examination in 2023 was about 4.1%. Isolation and culturing was more accurate than nucleic acid detection and serological test in the detection of Mp in healthy population as the latter two methods would overestimate the rate.

Bitter taste receptors,also known as type 2 taste receptors(T2Rs),are found not only in the mouth's taste bud cells but also in various tissues and cells,including macrophages.Macrophages,known for their re-markable plasticity,play a crucial role in regulating innate immunity,managing inflammation,and orchestrating immune responses to antigens,pathogens,and environmental factors.Recently,the study of the expression and function of bitter taste receptors within macrophages has garnered significant interest.This review summarizes the expression levels and dis-tribution characteristics of bitter taste receptors in macrophages and examines their effects on macrophage polarization,phagocytosis,and chemotaxis,as well as their potential molecular mechanisms.The purpose of this review is to provide in-sight and perspectives for research on the regulatory role of T2Rs in macrophage functions.

Objective:To observe the effects of Jiaji electroacupuncture combined with treadmill running training on tibial bone density,volume and number of blood vessels and VEGF expression after sciatic nerve amputation injury in rats,and provide theoretical basis for promoting tibial reconstruction after Jiaji electroacupuncture combined with treadmill running training. Method:A total of 180 SD rats were randomly divided into normal control group,model control group,Jiaji electroacupuncture group,treadmill group,combination treatment group(Jiaji electroacupuncture+treadmill),with 36 rats in each group.After 2,4 and 8 weeks of postoperative intervention,the rats were divided into 3 subgroups,12 in each subgroup.The model was made by suture of sciatic nerve dissociation injury.The normal control group received no intervention;the model control group received no intervention post-modeling.The Jiaji electroacupuncture group,treadmill group and combined group began to receive Jiaji electroacupunc-ture,treadmill training and combined treatment respectively on the 3rd day after surgery.Bone density of tibia was analyzed by Micro-CT scan.The number and volume of the proximal tibial vessels were analyzed by angi-ography.The expression of VEGF mRNA and protein in tibia was detected by RT-PCR and Western Blot.VEGF concentration in tibial bone marrow was determined by ELISA. Result:At 2,4 and 8 weeks post-intervention,the model control group showed significantly lower tibial bone mineral density,proximal vascular volume and quantity,VEGF mRNA and protein expression in bone tissue,and VEGF concentration in bone marrow compared to the normal control group at the same time point(P＜0.05).However,overtime,the tibial bone mineral density,the volume and number of proximal blood ves-sels,VEGF mRNA and protein expression in bone tissue and VEGF concentration in bone marrow of rats in the Jiaji electroacupuncture group,treadmill group and combination group were significantly higher than those in the model control group at the same time point(P＜0.05),and the combination group showed the most pro-nounced effects(P＜0.05). Conclusion:Jiaji electroacupuncture combined with treadmill training may improve tibial bone mineral density by up-regulating the expression of VEGF in tibia and bone marrow.