Objective To analyze the disease spectrum of abdominal external hernia during medical selection of flying cadets and compare the medical standards between US Air Force and Chinese PLA Air Force in order to improve the system of medical selection.Methods The data about abdominal external hernia among flying cadets during Chinese PLAAF medical selection between 2012 and 2015 were retrospectively analyzed and compared with the medical standards of the USAF flying cadets.Results Twenty-nine candidates were eliminated because of hernia,including 4 cases of hiatal hernia,3 cases of umbilical hernia and 22 cases of inguinal hernia.4.70% of the candidates were eliminated because of hernia disease.Empirical research showed difference in hernia standards between China and the USA.Conclusion Compared with Chinese medical selection standards,the USAF standards give more weight to whether the symptoms of disease impact air safety and efficiency.Our medical selection standards need to be improved by learning from foreign practices.

Three plasmids (pGenesil-P1, pGenesil-P2, pGenesil-P3) with different p27Kip1-shRNA sequences were designed and synthesized. Their effects on the proliferation of bovine corneal endothelial cells (bCEC) were investigated. Plasmid expressing irrelevant shRNA with a random combination was used as negative control (pGenesil-HK). The recombination of four plamids was confirmed by restrictive enzyme digestion and sequence analysis. The expression of mRNA and protein of p27Kip1 was detected by RT-PCR and Western blotting after stable transfection. The expressions of p27Kip1 mRNA and p27Kip1 protein of pGenesil-P1 group, pGenesil-P2 group and pGenesil-P3 group were all lower than those in the pGenesil-HK group and the blank group (non-transfected group). pGenesil-P3 had the strongest inhibitory effect and was selected for the next steps. The proliferation rates of the pGenesil-P3 group, the pGenesil-HK group and the blank group were assessed by MTT. The influence of shRNA-p27Kip1 on bCEC cell cycle was detected by flow cytometry (FCM). Compared with the control groups, the proliferation rate of the pGenesil-P3 group was increased significantly, and the ratio of S-phase also increased. It is concluded that shRNA-p27Kip1 could down-regulate the expression of p27Kip1 effectively and increase the proliferation of bCEC. RNA interference (RNAi) may be an effective means to promote the proliferation of CEC.
Cell Proliferation ; Cornea/cytology ; Cyclin-Dependent Kinase Inhibitor p27/*metabolism ; Endothelial Cells/*cytology ; Endothelial Cells/metabolism ; Gene Expression Regulation ; Models, Biological ; Plasmids/metabolism ; RNA Interference ; RNA, Messenger/metabolism ; RNA, Small Interfering/metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Tetrazolium Salts/pharmacology ; Thiazoles/pharmacology ; Transfection

Objective : To investigate a cluster of coronavirus disease 2019 (COVID-19) in Pingyang County,and to put forward targeted prevention and control suggestions. Methods: According to the Prevention and Control Plan of COVID-19 (Third Edition),we carried out epidemiological investigation to collect the information of demographic features,diagnosis and treatment,clinical manifestations,laboratory examination,exposure history and close contact. We analyzed the mode and frequency of exposure,so as to figure out the route of transmission. Results: This epidemic resulted in 6 confirmed cases of COVID-19 and 3 asymptomatic cases,with an attack rate of 6.52% (9/138). The median age of the cases was 48 years old. The confirmed cases mainly had imaging features of pneumonia, fever and cough. Their incubation period ranged from 4 to 9 days,and the median was 6 days. The first case,Wang,returned for the funeral of her grandmother from Wuhan with his husband and son on January 18 and lived with her mother. She had cough on January 19,and went to see her grandmother during January 19 to 23. She had contact with 6 cases,and the other 2 cases were Wang's mother and husband,who lived with Wang. All the cases except Wang had no COVID-19 related symptoms before the funeral,no contact history of COVID-19 cases or no other common exposure history except during the funeral. Therefore,Wang was determined as the source of the epidemic,staying in the same room and eating at the same table with her were risk factors for the infection of COVID-19 in this epidemic (P<0.05). Conclusions This was a local clustering epidemic caused by COVID-19 imported cases from Wuhan. It spread mainly by close contacts like staying in the same room and eating at the same table.

Three plasmids (pGenesil-P1, pGenesil-P2, pGenesil-P3) with different p27Kipl-shRNA sequences were designed and synthesized. Their effects on the proliferation of bovine corneal endo- thelial cells (bCEC) were investigated. Plasmid expressing irrelevant shRNA with a random combi- nation was used as negative control (pGenesil-HK). The recombination of four plamids was con- firmed by restrictive enzyme digestion and sequence analysis. The expression of mRNA and protein of p27Kipl was detected by RT-PCR and Western blotting after stable transfection. The expressions of p27Kipl mRNA and p27Kipl protein of pGenesil-P1 group, pGenesil-P2 group and pGenesil-P3 group were all lower than those in the pGenesil-HK group and the blank group (non-transfected group), pGenesil-P3 had the strongest inhibitory effect and was selected for the next steps. The pro- liferation rates of the pGenesil-P3 group, the pGenesii-HK group and the blank group were assessed by MTT. The influence of shRNA-p27Kipl on bCEC cell cycle was detected by flow cytometry (FCM). Compared with the control groups, the proliferation rate of the pGenesiI-P3 group was increased significantly, and the ratio of S-phase also increased. It is concluded that shRNA-p27Kipl could down-regulate the expression of p27Kipl effectively and increase the proliferation of bCEC. RNA interference (RNAi) may be an effective means to promote the proliferation of CEC.