Objective To study the variability of the parameters of the pedicle screw path and influencing factors of clinical significance. Methods A Picker PQ6000 Spiral CT was used to scan 736 vertebrae from C 3 to L 5 of 118 men and 80 women aged between 17 and 58. The largest transverse diameter, screw path length and e angle (the angle between the axis of the pedicle and sagittal plane) of each pedicle were measured. The contour of the vertebrae and the relationship of the sagittal axis of the spinal process, vertebral body and human body were inspected. Any discrepancy of these axes was measured and recorded. The gender, age, height and weight were recorded at the same time. Results Measurement of the biggest transverse diameter, screw path length and e angle at each vertebral level showed a wide range of value and quantity. Although the screw path length and the transverse diameter of the pedicle showed significant difference between man and woman, further covariance analysis for between subject effects revealed that no inter gender difference existed after the effects of height and weight were removed. Both height and weight showed significant positive correlation with the screw path length and transverse diameter of the pedicle, but no correlation with the e angle. Observation on the deformity of the vertebrae showed that the sagittal axes of the vertebral body and human body was discrepant in 14 thoracic and lumbar vertebrae; the sagittal axes of the spinal process and vertebrae was discrepant in 11 vertebrae; the transverse diameter of the pedicle was smaller than 4 mm in 14 vertebrae below T 9; 4 vertebrae showed lateral convex pedicle. Conclusion The parameters of the pedicle screw path varied in different subjects and different vertebral level with a large variability. The weight and height are two important factors to influence the parameters. Deformity is another factor which may lead to mistake of placement of the pedicle screw. To improve the accuracy of the pedicle screw, individual identification of the entering point and orientation should be considered and in some circumstances even special screws, should be used.

Objective To evaluate tumor angiogenesis and clinical significance by contrast-enhanced CT in case of non-small cell lung cancer (NSCLC). Methods 30 patients with NSCLC underwent dynamic thoracic CT, and histopathological slides were carefully prepared for VEGF immunohistochemical staining. Maxium attenuations of dynamic CT were compared with VEGF expression levels and lymph-node metastases. Results The mean peak attentation was (36.28?6.41)HU, VEGF positive expressions were in 21 patients, and negative expressions were in 9 patients. VEGF expression levels in patients with NSCLC stage II and III were higher than those in stage I , and in lymph node metastases group, the expression levels of VEGF were also higher than those in non-metastatic nodes. CT enhancement of NSCLC was positively related to VEGF expression,neoplasm stage and lymph-node metastases. Conclusion CT enhancement of NSCLC can reflect tumor angiogenesis and correlate to lymph-node metastases closely, help lung cancer diagnoses,neoplasm stage, and serve as a supplement to the present staging system for lung cancer in biological behavior.

Objective To study the influence of probiotic bacteria on rats blood lipids and immune function.Methods Rats fed with high fat diet,as a positive control of lovastatin in different kinds of experimental rats fed with probiotic bacteria.Before the experiment and 30 days after the experiment,the serum TC,TG and immune indicators were examined,compared with the control group.Results Probiotic bacteria feeding rats compared with control group rats,TC and TG in probiotic bacteria feeding rats blood are obviously lower than the eontroled group,(P＜0.01),the immune index is obviously higher than the control group (P＜0.05).Conclusion Probiotic bacteria obviously reduces TG and TG in Probiotic feeding rats blood,and improves the immunological function of probiotic bacteria feeding rats.

Objective: To explore the correction factors of lung cancer caused by radon exposure in a uranium mine, and estimate the excess relative risk (ERR) coefficient of lung cancer caused by radon in the uranium miners. Methods: Male miners who worked in a uranium mine more than one year in Hunan Province from 1958 to 2018 were selected. This study preliminarily estimated the ERR coefficient of lung cancer caused by radon in the miners with different corrections using the Possion regression model. Results: This study cohort included 4 851 uranium miners, with 187 miners died with lung cancer from 1958 to 2018, and cumulative follow-up of 207 251 person-year. The ERR coefficient of lung cancer caused by radon without correction factors was estimated to be 0.21%/WLM (95%CI: 0.04%/WLM-0.27%/WLM). In the final model, the exponential correction factors of radon-induced lung cancer were time since exposure and exposure rate. In this model, if time since exposure was 45 years and the average exposure rate was 0.14 WL, the estimated ERR coefficient was 1.73%/WLM (95%CI: 0.36%/WLM-3.11%/WLM). The ERR decreases by about 60.00% for every 10 years since exposure, and increases by about 30.00% for every one WL increase exposure rate. Conclusion: The correction factors of lung cancer caused by radon in uranium miners in this mine were the time since exposure and exposure rate. It was preliminarily estimated that the ERR coefficient of lung cancer caused by radon in the occupational radon exposed population in this uranium mine was 1.73%/WLM (95%CI: 0.36%/WLM-3.11%/WLM).

Objective To prepare a human meningococcal reference serum and standardize IgG concentrations to capsular polysaccharides and in vitro bactericidal activities of the reference serum against serogroup A, C, Y and W135 strains.Methods Twenty healthy adults were recruited and given one dose of immunization with tetravalent (serogroups A, C, Y and W135) meningococcal polysaccharide vaccine . Plasma samples were collected and gone through a series of process treatments including defibrination , filtra-tion, and lyophilization to prepare the meningococcal reference serum Men 10.The IgG concentrations of Men10 to capsular polysaccharides of serogroups A , C, Y and W135 were calibrated by using an internation-al reference serum CDC1992 as the standard in enzyme-linked immunosorbent assay (ELISA).Provisional IgG concentrations of Men10 were intensively validated by testing a panel of 12 calibration serum samples from Centers for Disease Control and Prevention , USA ( US CDC) and a panel of 56 serum samples immu-nized with A, C, Y and W135 meningococcal polysaccharide vaccine from Lanzhou Institute of Biological Products Co., Ltd.(LIBP) with the assays using Men10 and CDC1992 as the standard and/or test sam-ples, respectively.The bactericidal titers against serogroup A , C, Y and W135 strains were measured by se-rum bactericidal assay (SBA).Results Four thousand vials (0.5 ml/vial)of lyophilized human meningo-coccal reference serum Men10 were successfully prepared with 2.5%of residual moisture .Reference serum Men10 was sterile and free from contamination by hepatitis B virus , hepatitis C virus , human immunodefi-ciency virus and syphilis .Provisional IgG concentration of Men 10 to capsular polysaccharide of serogroups A, C, Y and W135 was calibrated by using CDC1992 as the standard.Furthermore, IgG concentrations of both panels of 12 CDC calibration serum samples and 56 LIBP serum samples calibrated by using Men 10 as the standard correlated well with those by using CDC1992 as the standard (r=0.99,P<0.05).The IgG concentrations of CDC1992 as calibrated by using Men10 as the standard showed significant correlation with its previously determined values with variation <10%.SBA titers for serotype A , C, Y and W135 strains were established as well .Conclusion A panel of new human meningococcal reference serum Men 10 with accurately calibrated IgG concentration against capsular polysaccharide of serogroups A , C, Y and W135 as well as SBA titers was successfully established .

Objective To investigate the clinical value of 2 dimension late Gadolinium enhancement MRI (LGE-MRI) technique for the evaluation of atrial myocardial fibrosis in patients with atrial fibrillation. Methods Forty-nine cases of atrial fibrillation in our hospital from March 2015 to December 2016 were retrospectively collected. The LGE-MR was acquired by the Siemens 3.0 T MR machine before the catheter ablation.The findings of LGE-MR were evaluated by two experienced doctors. The left atrium(LA)were manually segmented into 8 regions in axial view.All patients were classified into 4 stages based on the extent of enhancement, stage 0: absence of enhancement, stage Ⅰ: enhancement appeared in minimal two consecutive slices in single region,stageⅡ:enhancement in two regions,stageⅢ:enhancement in three or more regions. All electroanatomic maps were obtained after electrical conversion during catheter ablation. The Kappa test was used to assess the consistency of LGE-MRI left atrial myocardial fibrosis and CARTO system of the left atrial endocardial voltage reconstruction. Results Forty-nine cases of atrial fibrillation with LGE-MRI and CARTO were included. There were 17 cases of atrial fibrosis stage 0,10 cases of stageⅠ,11 cases of stageⅡ,11 cases of stageⅢaccording to LGE-MRI findings;There were 17 cases of atrial fibrosis stage 0,19 cases of stageⅠ,12 cases of stageⅡ,11 cases of stage Ⅲ with reference to CARTO findings. The diagnostic accuracy of the LGE-MRI atrial fibrosis was 81.6%(40/49),of which the correlation was good(Kappa= 0.751,P<0.001). Conclusions LGE-MRI can accurately assess the degree of left atrial myocardial fibrosis in patients with atrial fibrillation,help to select the proper candidate and strategy in catheter ablation.