Rheumatoid arthritis(RA)is a serious autoimmune disease.Type Ⅱ collagen induced murine arthritis(CIA)displays polyarthritis and causes chronic and destructive joint damages,which is similar to RA in many aspects.CIA is widely used for the research on RA pathogenesis and drug discovery.In this review,we discussed the establishment of CIA and the key factors participating in the CIA pathogenesis.

Objective To explore the abilities and personal qualities that medical undergraduates need for their future clinical work, and develop their competency model. Methods The self-made ques-tionnaire survey on medical undergraduates' competencies was conducted among the 1326 medical under-graduates in a medical university by using the cluster sampling method, and the 1099 effective question-naires were collected with effective rates of 82.88%. The exploratory factor analysis was used to analyze the internal structure of competency item and to build the competency model. The rating method was used to calculate the weight of each competency item. Results The overall Cronbach's alpha coefficient of the competency questionnaire was 0.965, and the coefficient of each dimension was above 0.832. The KMO statistic value was 0.970, and the probability associated with Bartlett test statistic was P=0.000, showing that the questionnaire has high reliability and validity. The competency model of medical undergraduates covers six aspects, namely, craftsmanship, personal qualities, professional learning, interpersonal communication, psychological adaptation and the pursuit of excellence, which contain 49 factors. The cumulative variance contribution rate was 54.729%. The weights of these six aspects in the model were 0.204 4, 0.202 1, 0.175 3, 0.158 8, 0.137 6 and 0.121 8 respectively. Conclusion The competency model of undergraduate medi-cal students has a certain scientific and practical value, which can provide new evaluation methods and ideas for medical education objectives, quality assurance, teaching evaluation, medical personnel selection and training.

Objective To build a multi‐level hierarchical structure model of the influencing factors for hierarchical medical system ,to identify the role relationship between all the factors and transmission pathways ,and to recommend on developing China′s hierarchical medical system . Methods Thirty influencing factors were identified in a screening based on literature review for the hierarchical medical system .On such basis ,16 influencing factors were identified by three health policy experts ,which affect operations of the current system .Interpretative structural modeling was called into play in the end to analyze the hierarchy relationship between various influencing factors and the conduction loops .Results There exist among the 16 factors a 3‐level hierarchical structureand two conduction loops .The factor directly limiting the hierarchical medical system is two‐way referral,and most internal core drivers arehuman resources development and governance mechanism.By means of self‐growth and external constraints ,they exert their influence on the operation of hierarchical medical system .Conclusions There are interactive hierarchical effects among the factors ,merging into three node elements of functional role,inter‐entity relationshipand patient participation.