Principles of medical equipment course were explored of formative evaluation as the center examination,constructed an examination reform scheme as” One center (formative evaluation as the center),three systems (content system,operation system,monitoring system).” Made students to learn from the center of focus scores change to autonomous learning and culture analysis,solves the question ability and practical ability.At the same time,strengthen the teaching process of teaching and learning to communicate and exchange,Get the students learning feedback information to improve teaching and learning in time,Strengthen the students′ ability of autonomous learning and lifelong learning ability.

OBJECTIVETo explore the feasibility of establishing an isolated porcine liver machine perfusion model and assess its value in high-intensity focused ultrasound studies.

METHODSTwenty-one isolated porcine livers were perfused with autologous blood for 4 h through dual vessels (portal vein and hepatic artery) cannulation using an extracorporeal circulation machine under a sub-normothermic perfusion condition. The perfusion model was assessed by monitoring the liver color, texture, liver weight gain, hemodynamic parameters, color Doppler flow imaging, bile output and histopathology.

RESULTSNineteen isolated porcine livers were successfully cannulated with dual vessels, and failure of hepatic artery intubation occurred in two porcine livers. After machine perfusion for 4 h, the isolated livers maintained a soft texture with stable hemodynamic levels within relative normal physiological ranges. The bile output was more than 3 ml/h within the initial 3 h of perfusion. Histopathological examination demonstrated no morphological or structural changes of the liver tissues.

CONCLUSIONThe isolated porcine liver perfusion model is stable and feasible, and can be used for high-intensity focused ultrasound studies.

Animals ; Equipment Design ; Extracorporeal Circulation ; instrumentation ; methods ; Hemodynamics ; Liver ; blood supply ; diagnostic imaging ; Liver Circulation ; physiology ; Swine ; Ultrasonography

In the practical teaching of large-scale medical equipment courses in medical colleges and universities. There are some problems such as less opportunities for students to operate the equipment which is possessed by teaching hospitals, the large-scale medical equipment in teaching hospitals are in a pathogenic environment, and some equipment such as CT, DR have radiation hazards, which lead to difficulties in practical teaching. These problems restrict the cultivation of students' practical ability, cause disconnections between theoretical teaching and practical teaching, and are not conducive to training "new engineering" and "new medical science" talents. So, this paper puts forward an idea which introduces virtual simulation teaching instruments of large-scale medical equipment into the teaching of medical equipment in medical colleges and universities, uses the physical structures, control systems and functional software of virtual simulation teaching instruments to implement the teaching of "integration of theory and practice", and also sets up validation experiments, comprehensive experiments, designing experiments and research explorative experiments in the teaching process. This kind of teaching can not only realize the high integration of theoretical teaching and practical teaching, but also consolidate students' basic theoretical knowledge, improve their abilities to solve complex engineering problems, and cultivate "new engineering" and "new medical" talents in line with the needs of the new era.

Objective: Abstract: Objective: cancer cells and its effects on the proliferation and migration of gastric cancer cells. Methods: The expression level of LINC00473 in gastric cancer cells was verified by qRT-PCR system. LINC00473 siRNA segment and overexpression vector were separately transfected into gastric cancer cells by the method of lipofection. The proliferation and migration abilities of gastric cancer cells with LINC00473 knockdown or overexpression in vitro were evaluated by cell counting kit-8 (CCK8) assay, colony formation assay and Transwell migration assay. The expression levels of proteins involved in epithelial-mesenchymal transition (EMT) were examined by western blot analysis. Results: The expression levels of LINC00473 were decreased in gastric cancer cells compared with that in human gastric epithelial cell strain GES-1 (P＜0.05). LINC00473 knockdown cells showed significant increased ability for cell growth (F=163.10, P＜0.01) and colony formation (t=3.29, P＜0.05) compared with the knockdown cells in scramble control. The results of Transwell migration assay showed that LINC00473-knockdown enhanced the migratory abilities of gastric cancer cells (t=4.68, P＜0.05). The knockdown of LINC00473 downregulated E-cadherin expression (t=4.08, P＜0.05) and upregulated N-cadherin (t=5.06, P＜0.01), Snail (t=7.69, P＜0.01) and Vimentin (t=3.82, P＜0.05) expression. Compared with the control group, LINC00473 overexpression cells showed significantly decreased cell growth (F=186.00, P＜0.01) and colony formation ability (t=3.22, P＜0.05). The results of Transwell migration assay showed that LINC00473-overexpression reduced the migratory ability of gastric cancer cells (t=5.52, P＜0.05). The overexpression of LINC00473 enhanced E-cadherin expression (t=2.90, P＜0.05) and reduced the expressions of N-cadherin (t=7.44, P＜0.01), Snail (t=2.78, P＜0.05) and Vimentin (t=4.64, P＜0.01). Conclusion The knockdown of LINC00473 may promote gastric cancer cell proliferation and migration in vitro by regulating EMT.

Objective: To investigate the function of virD4 gene in Helicobacter pylori clinical strain SBK. Methods: The virD4 gene segment was obtained through T-A cloning method. The prokaryotic expression vector pET-28a(＋)-virD4 was constructed and transformed into E. coli Rosetta for the expression by induction of IPTG. The recombinant proteins were obtained and purified by KCl dyeing with gel cutting method, and identified via SDS-PAGE analysis. The purified recombinant virD4 protein was used to immunize mice to produce polyclonal antibodies. The titer of the polyclonal antibodies was tested by ELISA and the antigenic specificity was identified by western blot. The purified recombinant virD4 proteins were co-cultured with GES-1 cells followed by detecting the expression of inflammatory cytokines secretion and the ability of cell proliferation. Results: The full length of virD4 gene was 1 728 bp. The sequence shared quite high homology with the virD4 gene of isolate Shi470. The recombinant prokaryotic expression plasmid pET-28a(＋)-virD4 was successfully constructed. The recombinant virD4 proteins were obtained by IPTG induction and purified via KCl dyeing method. SDS-PAGE showed that the relative molecular weight of recombinant virD4 protein was 63 000. The purified proteins were used to immunize mice to obtain the anti-virD4 polyclonal antibodies with the titer 512 000. The reaction between anti-virD4 polyclonal antibodies and recombinant virD4 proteins was highly specific. The recombinant virD4 protein induced inflammatory cytokines secretion and promoted GES-1 cell proliferation. Conclusion The virD4 gene was successfully cloned and highly expressed in prokaryotic expression system, and its antibodies were prepared. The recombinant virD4 protein can induce cytokine secretion and cell proliferation.