Objcetive To investigate the protective effects of the nitroxides R-1 on human liver cells exposed to ionizing radiation.Methods Human liver cells L-02 were cultured and irradiated with 60Co γ-rays at the doses of 0,1,2,4,and 8 Gy,in order to screen the proper irradiation dose.WR2721 at the terminal concentration of 4 mmol/L was used as positive control.L-02 cells irradiated with 4 Gy were added with R-1 at the terminal concentration of 0.25 μmol/L at 30 min before irradiation or immediately after irradiation.MIT method was used to screen the proper conditions for follow-up experiment 72 h later.L-02 cell culture fluid was added with R-1 at the concentrations of 0,0.125,0.25,0.5,and 1 μmol/L,respectively for 30 min before irradiation at the doses of 0,1,2,4,and 8 Gy to ealculate clone formation rate at 10 d post-irradiation.L-02 cells were cultured and divided into 4 groups:control group without any treatment.drug group pretreated by 0.25 μmol/L R-1 only,irradiation group,irradiated at 4 Gy only,and drug + irradiation group with combination of 0.25 μmol/L R-01 and 4 Gy irradiation.The inverted microscopy and Hoechst 33258 staining and flow eytometry were used to observe the apoptosis of the cells at 24,48,and 72 h later.Results Nitroxides R-1 did not inhibit the viability of L-02 cell when its concentration was less than 1 μmol/L and it inhibited the L-02 cell growth when the concentration wu higher than 2 μmoL/L.The A value and colony formation rate of different concentration of R-1 groups were all higher than those of the irradiation group,and the effect of the 0.25 μmol/L drug concentration group was the most significant.Consequently,the concentration 0.25 μmoL/L was selected for follow-up experiment.Compared with the irradiation group,the L-02 cells of the pretreatment group showed solid adherence, increased refraction,clear outline,less apoptotic and dead cells at 4 Gy post-irradiation.Conclusions Nitroxides R-1 can protect the human liver cells from 60Coγ-ray induced injury effectively.The mechanism of its protective effect may be the reduction of apoptosis.

Objective: To establish a new method for determining residual organic solvent DMF in imiquimod. Methods: The samples were injected into an Agilent HP-PLOT/Q capillary column(30 m × 0. 530 mm,40. 0 μm) by a headspace sampler and ana-lyzed with an FID detector, the carrier gas was nitrogen, the inlet temperature was 250℃, and the detector temperature was 270℃. The column temperature was programmed raised. Results: The resolution among the peaks of DMF and the other residual solvents could meet the requirements. There was a good linearity within the experimental concentration range. The average recovery was 94. 6%(RSD=4. 0%, n=9). The limit of quantification and the limit of detection was 4. 809μg·ml-1 and 0. 963μg·ml-1, respectively. Conclusion:The method is convenient, accurate and sensitive, which can be used in the determination of residual solvent DMF in imi-quimod.

Objective To study the effect of age on the hemodynamics of common carotid artery. Methods 47 healthy volunteers werestudied. Wall shear stress (WSS) values localized at common carotid artery 2 cm below the bifurcation were calculated with cine phase-contrastMR imaging combined three-dimensional paraboloid (3DP) model. On the spatial distribution, common carotid artery wall was dividedinto 24 equal parts. Calculate the mean WSS in a cardiac cycle on each part, and choose the minimal WSS value. Then the effects of age onthe average WSS and minimal WSS were observed. Results Total 94 common carotid arteries of 47 health volunteers were examined, inwhich 9 carotid arteries in 9 volunteers were excluded because of uninterpretable high-resolution MRI findings or volunteer's intolerance forthe detection. In the remaining 85 common carotid arteries, the average WSS and the minimal WSS during a cardiac cycle on the spatial distributionwere (7.45±2.12) dyne/cm2 and (5.98±1.93) dyne/cm2 respectively. Both average WSS and minimal WSS were negative correlatedwith age (P<0.05). Conclusion With the age increased, mean WSS and minimal WSS on the spatial distribution of common carotid arterydecreased.

Traditional thoracic surgery teaching has many problems, such as limited classroom teaching time allocation, many diseases and difficult to fully cover classroom teaching, uneven practical teaching level, and difficulty in updating "big textbooks". The Department of Thoracic Surgery of The Second Affiliated Hospital of Air Force Medical University has gradually applied microlecture to all levels of thoracic surgery teaching, such as undergraduate auxiliary classroom teaching and clinical skills training, grassroots and refresher doctor training, postgraduate education, etc., and has achieved good results of teaching effect.

OBJECTIVE：To establish a method for online detection of antioxidant active components in Glycyrrhiza uroalensis decoction pieces ，and to identify it. METHODS ：The free radical scavenging rate of 1，1-diphenyl-2-trinitrobenzene hydrazine （DPPH）was determined to evaluate the antioxidant activity of G. uralensis decoction pieces. HPLC-UV-DPPH method was used to screen the anti oxidant active components of G. uralensis decoction pieces. HPLC-TOF/MS was used to obtain mass spectrum data and Qualitive Analyst B 06.00 Build 6.0.633.0 software was used to analyze data. Through contrast analysis of UV absorption spectrum，online chromatogram ，mass spectrum information of G. uralensis and the retention time of each compound ，accurate molecular weight ，antioxidant active components were identified by referring to relevant literature. Validation test was also conducted. RESULTS ：DPPH free radical scavenging rate in 8 batches of G. uralensis decoction pieces ranged 55.71％-60.17％. Seven antioxidative active compounds ，including avolomotor ，8-isopentenyl naringin ，yellow lupulin weitone ，isoflavone B ，3′， 4′-dimethoxy3-hydroxy-6-methyl flavone ，glycyrrhizin E and glycyrrhizin H ，could be screened from G. uralensis decoction pieces. After validation ，the peak area of inverted peak generated by online reaction was positively correlated with DPPH free radical scavenging rate. CONCLUSIONS ：Established method is simple and accurate ，and can be used to quickly screen and identify the main antioxidant components of G. uralensis decoction pieces ；the peak area of inverted peak can be used to evaluate the antioxidant active components of G. uralensis decoction pieces.