Based on the theory of engineering medicine,a consensus which takes the basic medical ethics of harm reduction as the starting point is proposed to addresses the current clinical problems of a wide variety of radiotherapy setup equipments and methods,large differences by principles,and inaccurate setup.The consensus is formed in two aspects.(1)Advocate coordination of multiple setup methods for joint setup;collect,compare,analyze and screen data on setup methods;determine the operational guidelines and methods for joint setup based on the principle of standardized and unified clinical consistency,with a view to achieving the clinical purpose of greatly ensuring the precision of radiotherapy setup and radiotherapy safety without relying on the golden standard.(2)Standardize the operational methods for tracing setup deviations,so that when the difference in setup leads to poor clinical consistency,the cause of deviation can be traced and the effectiveness of different setups can be screened.Based on the concept of engineering medicine,the consensus is expected to standardize the method of radiotherapy setup,realize accurate radiotherapy,improve treatment effect and show medical ethical care.

Based on the theory of engineering medicine,a consensus which takes the basic medical ethics of harm reduction as the starting point is proposed to addresses the current clinical problems of a wide variety of radiotherapy setup equipments and methods,large differences by principles,and inaccurate setup.The consensus is formed in two aspects.(1)Advocate coordination of multiple setup methods for joint setup;collect,compare,analyze and screen data on setup methods;determine the operational guidelines and methods for joint setup based on the principle of standardized and unified clinical consistency,with a view to achieving the clinical purpose of greatly ensuring the precision of radiotherapy setup and radiotherapy safety without relying on the golden standard.(2)Standardize the operational methods for tracing setup deviations,so that when the difference in setup leads to poor clinical consistency,the cause of deviation can be traced and the effectiveness of different setups can be screened.Based on the concept of engineering medicine,the consensus is expected to standardize the method of radiotherapy setup,realize accurate radiotherapy,improve treatment effect and show medical ethical care.

Practice teaching is an important link in the training of public health talents in colleges and universities. At present, there are still some problems in the education of public health and preventive medicine in the colleges and universities in China, such as attaching greater importance to theory than to practice and weak training of practical skills among students. In view of this situation, a public health practice teaching model of "internal-external interactions" has been constructed in Dalian Medical University with focuses on the following aspects: ①experiments in the university are optimized based on social needs; ②the practice base outside the university is expanded based on the teaching in the university; ③"internal-external interactions" are adopted to enhance practice training and improve post competence. The teaching practice shows that the implementation of the teaching model of "internal-external interactions" can help to improve practice teaching ability, promote the improvement in the training quality of public health talents, and meet the social demand for application-oriented professionals.

To adapt to the new challenge of nutrition and food safety as well as to cultivate talents with capacity of innovation and practical application, Dalian Medical University starts to explore a wide range of experimental teaching system:expanding classical confirmatory experiment, offering comprehensive and designing experiment , encouraging students to participate in scientific research , building Internet teaching platform, and initiating community practice service projects. Multiple dimensional and teaching patterns contribute to strengthen basic skills, interest in scientific research, innovation consciousness and practical ability of undergraduate students, which greatly improves their consciousness of social service and responsibility and helps to cultivate the practical professional talents.

OBJECTIVETo explore whether there is difference in arsenicals-induced DNA damage of human lymphocyte.

METHODSLymphocyte were sterilely collected from healthy donor and exposed to sodium arsenite (AsIII), sodium arsenate(AsV) and methyl sodium arsenate(MAsv) at 1,5,10,20 and 50 mumol/L. After incubation of 24 hours, cells were collected by centrifugation and DNA damage was detected by single cell gel electrophoresis (SCGE).

RESULTSThe comet frequency distribution of all groups except 1 mumol/L group of MAsV were significantly different from that of control. The comet length of all groups except 1 mumol/L group of AsV and 1.5 mumol/L groups of MAsV were significantly higher than that of control. There were correlations between the doses of arsenicals and the ratios of comet cell or length of comet(rAsIII = 0.8134, rAsV = 0.8734, rMAsV = 0.8994).

CONCLUSIONDNA damage in human lymphocyte were induced by all the three arsenicals. A dose-effect relationship was observed between exposure doses of the same arsenical and DNA damage. With different arsenicals but the same exposure dose, the DNA damage level was as follow: AsIII > AsV > MAsV.

Arsenates ; toxicity ; Arsenites ; toxicity ; Comet Assay ; DNA Damage ; Dose-Response Relationship, Drug ; Humans ; Lymphocytes ; drug effects ; ultrastructure

Objective To study the effect of cellular glutathione (GSH) in relieving the cytotoxicity induced by arsenic on HaCaT. Methods The HaCaT cells were pre-treated with N-acetylcysteine (NAC) and L-buthionine-[S'R]-sulfoximine (BSO) for 24 h, then treated with sodium arsenite (NaAsO2) by adding it into the medium for 24 h. Alarmarblue assay was used to detect the proliferation of the cells. Results The reduction rate of Alarmarblue increased when the HaCaT cells were treated with 0.001-10.000 ?mol/L of NaAsO2 alone (P