Objective To determine whether the candidates who were disqualified for having phoria or tropia in People′s Liberation Army Air Force ( PLAAF) medical selection of flying cadets are qualified or not according to United States Air Force ( USAF) Medical Standards Directory , and to raise suggestions on revising PLAAF medical standards . Methods All the candidates who had participated in the final medical selection of flying cadets were reevaluated and determined as qualified or not according to USAF Medical Standards Directory .Results There was a marked difference between disqualification rates of PLAAF and USAF .13.87%of the candidates who were regerded as disqualified by PLAAF standards were qualified according to USAF Medical Standards Directory .These cadets might be eliminated by mistake . Conclusion The standard on heterophonies of the PLAAF is more stringent than that of the USAF .We shoucd revise PLAAF standards using USAF standards for reference .

The combination of healthcare and artificial intelligence is an important direction of medical development. The authors summarized the application of artificial intelligence in such fields as diagnosis, treatment, prevention, scientific research, teaching among others. The analysis covers the problems and challenges facing the development of artificial intelligence, and looks forward to the application prospect of artificial intelligence.

With the development of big data, the Internet and information technology, artificial intelligence is gradually being applied to the field of hospital management. The authors used advanced artificial intelligence technology to conduct structured collection and monitor the hospital′s current medical quality data, identifying key points and key events affecting medical quality and safety from the link, and providing medical personnel′s behavior with pre-warning, process monitoring and post-evaluation to improve hospital medical quality management.

BACKGROUND:In recent years,some scholars in the field of tendon bone injury have attached stromal cell-derived factor 1 to tissue engineering scaffolds to promote tendon bone healing,and achieved good results.However,whether stromal cell-derived factor 1 promotes tendon bone healing mechanisms and participates in the repair of natural healing has not yet been defined. OBJECTIVE:To study the expression of stroma-cell derived factor 1 during tendon bone healing after rupture of the whole supraspinatus muscle of the rabbit rotator cuff and its migration effect and optimal in vitro migration promoting concentration on stem cells during tendon bone injury. METHODS:Totally 18 adult New Zealand rabbits were randomly selected to establish rotator cuff injury models,and an additional 3 rabbits were selected as blank controls.At 3,5,7,14,21,and 28 days after modeling,three rabbits were executed separately and the rabbits in the blank group were sacrificed.The tissues of tendon bone junction were taken and stored in a-80℃refrigerator.The expression of stromal cell-derived factor 1 was detected by ELISA at each time point after injury.Mesenchymal stem cells were isolated from the bone marrow of young rabbit femur,cultured,and identified.Transwell assay was performed to verify the migration-promoting effect of stromal cell-derived factor 1 on stem cells and the optimal migration-promoting concentration in vitro.The stem cells cultured to P3 were co-cultured with BrdU and injected into the rabbit ear marginal vein,and immunohistochemical staining was used to verify whether the stem cells migrated to the injury site. RESULTS AND CONCLUSION:(1)Stromal cell-derived factor 1 gene expression was bimodal during rotator cuff tendon bone healing.Stromal cell-derived factor 1 gene expression increased significantly at 3 days post-injury(P<0.01)and then decreased,reaching a minimum at 5 days post-injury.It increased again and reached a peak 14 days after injury(P<0.01)and then decreased.(2)Cell immunohistochemical staining displayed that stem cells labeled with BrdU did migrate to the injury site.(3)The results of the transwell experiment exhibited that 60-80 ng/mL stromal cell-derived factor 1 had the best effect on promoting migration of stem cells,while a concentration of 200 ng/mL inhibited migration.(4)Stromal cell-derived factor 1 is involved in the healing of rotator cuff tendon bone during the inflammatory response phase and the proliferation phase.The mechanism of action may be to promote the migration of stem cells to the injury and their differentiation into various types of cells to promote repair.In addition,the pro-migration effect of stromal cell-derived factor 1 exists at a range of concentrations,beyond which it may act as an inhibitor.