Objective: In view of the difficulty of the shortage of new coronavirus nucleal acid test in the early COVID-19 outbreak, to explore the application value of chest CT in screening COVID-19 patients. Methods: Retrospective analysis was performed on the data of patients with fever who received chest CT and new coronavirus nucleal acid test during January 25, 2020 to February 2, 2020 in Zhongnan Hospital of Wuhan University. A total of 587 patients were enrolled, including 290 males and 297 females, aged from 11.0 to 96.0 (51.3±17.1) years old. Take the nucleic acid test results as the gold standard, the sensitivity, specificity and rate of missed diagnosis of CT screening COVID-19 were calculated. Results: Among the 587 patients, there were 433 positive cases (73.8%, 433/587) and 154 negative cases (26.2%, 154/587) of novel coronavirus nucleic acid test. Using CT screening, 494 cases (84.2%, 494/587) were positive and 93 cases (15.8%, 93/587) were negative. The sensitivity of CT screening COVID-19 was 97.7% (423/433), specificity was 53.9% (83/154) and rate of missed diagnosis was 2.3% (10/433). Conclusions In the early COVID-19 outbreak, CT screening has the advantages of high sensitivity and low rate of missed diagnosis of COVID-19, which can compensate for the shortage of new coronavirus nucleal acid test and can be used as the basis for rapid screening for early prevention and control of COVID-19 outbreak.

Objective To investigate the current status of occupational health and related countermeasures in Guangzhou,China.Methods Related data were collected from occupational poisoning accident investigation,diagnosis and identification of occupational diseases,and the occupational disease hazard reporting system,and the statistical data of occupational health in Guangzhou were analyzed retrospectively.Results The number of enterprises reporting for occupational disease hazards in Guangzhou was 20 890,and the total number of workers was 1 457 583.The number of workers exposed to occupational hazards was 284 233,and the cumulative number of workers with occupational diseases was 1 502.There were many risk factors for occupational diseases in enterprises,and there were a large number of workers with occupational diseases,as well as newly diagnosed cases.From 2001 to 2014,the total number of cases of occupational diseases was 958.Conclusion The situation for the prevention and control of occupational diseases is grim in Guangzhou.Occupational health supervision and law enforcement should be enhanced,the three-level supervision system should be established and perfected,and the occupational health supervision system with a combination of "prevention,treatment,and protection" should be established and promoted,so as to gradually establish a technical service support system for occupational health.

Objective To investigate the current status of occupational health and related countermeasures in Guangzhou,China.Methods Related data were collected from occupational poisoning accident investigation,diagnosis and identification of occupational diseases,and the occupational disease hazard reporting system,and the statistical data of occupational health in Guangzhou were analyzed retrospectively.Results The number of enterprises reporting for occupational disease hazards in Guangzhou was 20 890,and the total number of workers was 1 457 583.The number of workers exposed to occupational hazards was 284 233,and the cumulative number of workers with occupational diseases was 1 502.There were many risk factors for occupational diseases in enterprises,and there were a large number of workers with occupational diseases,as well as newly diagnosed cases.From 2001 to 2014,the total number of cases of occupational diseases was 958.Conclusion The situation for the prevention and control of occupational diseases is grim in Guangzhou.Occupational health supervision and law enforcement should be enhanced,the three-level supervision system should be established and perfected,and the occupational health supervision system with a combination of "prevention,treatment,and protection" should be established and promoted,so as to gradually establish a technical service support system for occupational health.

OBJECTIVETo establish the method of high-performance liquid chromatography HPLC for the determination of N-acetyl-S-(2-carbamoylethyl)-cysteine (AAMA) in urine.

METHODSAfter acid hydrolysis, AAMA in urine was converted into S-2-carboxyethyl cysteine (CEC). CEC reacted with the derivative reagent ophthalaldehyde and formed the derivative with strong fluorescence absorption. The HPLC-fluorescence detector was applied, with an excitation wavelength of 340 nm and an emission wavelength of 450 nm.

RESULTSUrinary AAMA demonstrated an excellent linearity in the range of 5.3~123.5 μmol/L, with a correlation coefficient of 0.9994. The minimum detectable concentration was 0.1 μmol/L (the volume of urine sample was 1.0 ml), the recovery of standard addition was 97.4%~104.2%, and the between-run precision was 2.3%~4.3%. The sample could be stored in the refrigerator for at least 7 days at a temperature of 4℃.

CONCLUSIONThe method is simple, with a low cost, a high sensitivity, and good precision and accuracy, and the instrument and equipment commonly seen in laboratories are applied. Therefore, this method is worthy of wide application.

OBJECTIVETo investigate the application of risk grading and classification for occupational hazards in risk management for a shipbuilding project.

METHODSThe risk management for this shipbuilding project was performed by a comprehensive application of MES evaluation, quality assessment of occupational health management, and risk grading and classification for occupational hazards, through the methods of occupational health survey, occupational health testing, and occupational health examinations.

RESULTSThe results of MES evaluation showed that the risk of occupational hazards in this project was grade 3, which was considered as significant risk; Q value calculated by quality assessment of occupational health management was 0.52, which was considered to be unqualified; the comprehensive evaluation with these two methods showed that the integrated risk rating for this shipbuilding project was class D, and follow- up and rectification were needed with a focus on the improvement in health management.

CONCLUSIONThe application of MES evaluation and quality assessment of occupational health management in risk management for occupational hazards can achieve objective and reasonable conclusions and has good applicability.

Objective To explore the relationship between dyslipidemia and colorectal cancer.Methods The levels of total cholesterol(TC),triglyceride (TG),1ow density lipoprotein-cholesterol (LDL-C) and high density lipoprotein-cholesterol (HDL-C) of 182 patients with colorectal cancer and 86 controls were tested.The serum lipids levels between the colorectal cancer group and control group,colorectal cancer with different location,different gender were compared.Results The level of TC in the colorectal cancer group [(5.51 ± 0.76) mmol/L] was significantly higher than that of the control group [(4.84 ± 0 53) mmol/L] (t =2.41,P ＜ 0.05) ; The level of HDL-C in the colorectal cancer group[(0.85 ± 0.26) mmol/L] was significantly lower than that of the control group [(1.24 ± 0.27) mmol/L] (t =-3.56,P ＜ 0.05).There were no significant differences in the 1 evels of TG and LDL-C between the colorectal cancer group and control group(t＝0.89,1.45,all P ＞ 0.05).TC level in the male colorectal cancer group [(5.96 ± 0.87) mmol/L] was significantly higher than that of the female colorectal cancer group [(5.26 ± 0.74) mmol/L] (t =2.10,P ＜ 0.05).The level of TC in the distal colon and rectal cancer group was (6.07 ± 0.78) mmol/L,which was significantly higher than (5.14 ± 0.56)mmol/L of the proximal colon cancer group (t =3.24,P ＜ 0.05) ;The level of HDL-C in the distal colon and rectal cancer group was (0.75 ± 0.26) mmol/L,which was significantly lower than (1.07 ± 0.19) mmol/L of the proximal colon cancer group (t =-3.20,P ＜ 0.05).Conclusion TC was positively correlated with colorectal cancer,and HDL-C was negatively correlated with colorectal cancer.

Objective To compare the effect of endoscopic ultrasonography (EUS),magnetic resonance chlangiopancreatography (MRCP) and endoscopic retrograde cholangiography (ERCP) in the diagnosis of suspicious intermediate choledocholithiasis.Methods One hundred and eighty-six patients with suspicious intermediate of choledocholithiasis successively received MRCP,EUS,and ERCP examination.The stone taking out by endoscopic as diagnositic standard,and the sensitivity,specificity and accuracy in different methods was compared.Results Sensitivity and accuracy of EUS was significantly higher than that of MRCP [97.5％(155/159) vs.92.5％(147/159),97.3％(181/186) vs.91.9％(171/186)](x2 =4.21,5.30,P =0.04,0.02).There was no statistically significant difference between EUS and ERCP in specificity [96.3％(26/27) vs.88.9％ (24/27)] (x2 =115.40,P ＜ 0.05).Sensitivity,specificity and accuracy of ERCP was 98.9％(184/186),98.7％(157/159) and 100.0％(27/27),and there was no difference between EUS and ERCP in the diagnosis of choledocholithiasis (P ＞ 0.05).Conclusions EUS is similar with ERCP for the diagnosis of choledocholithiasis.By performing EUS or MRCP first,ERCP may be avoided in patients with suspicious intermediate choledocholithiasis.

Objective To observation the clinical effect of anesthesia combined with epidural block for patients with COPD surgery.Methods 262 cases with COPD needed to line the chest and abdominal surgery and urology surgery patients.Patients were divided into control group and observation group according to the time sequence,underwent general anesthesia and anesthesia combined with epidural anesthesia,contrast observed in patients with operative time,postoperative extubation time,wake time and the analgesic effect of anesthesia (VAS score) was measured in patients with FVC,FEV1/FVC and FEF25％ to 27％ lung function,clinical efficacy and complication rate of two anesthesia methods.Results The patients extubation time,recovery time and VAS scores were significantly lower than those of control group,the differences were statistically significant(all P ＜0.05).Group of postoperative patients with FVC,FEV1/FVC and FEF25％ to 27％,such as lung function test results were significantly better than those of control group,and the difference was statistically significant (all P ＜0.05).Anesthesia control group total effective rate of 87.0％ observed in patients anesthesia total effective rate was 96.9％.Compared with the control group,the anesthesia clinical effect of the observation group was statistically significant (P ＜0.05).Operative time and postoperative complication rate of the two groups of patients showed no significant difference(P ＞0.05).Conclusion Anesthesia combined with epidural anesthesia used in surgery in patients with COPD can effectively improve the clinical effects of anesthesia,to enhance the safety of anesthesia,which will help the rehabilitation of patients and worth of clinical practice.

Objective To investigate the role of voltage-gated potassium channel in the human skin squamous cell carcinoma A431 cells and human keratinocyte HaCaT cells. Methods MTT assay was performed to detect the effect of different concentrations of tetraethylammonium (TEA) on the proliferation of cultured A431 cells and HaCaT cells. Besides, enzyme-linked immunosorbent assay (ELISA) was conducted to detect the expression of HERG channel protein in A431 cells, HaCaT cells and normal human skin tissue.Results TEA inhibited the proliferation of A431 cells and HaCaT cells in a dose- and time-dependent manner.After treated with TEA (≥ 10 mmol/L) for 24 or more hours, the proliferation of A431 cells and HaCaT cells was obviously suppressed. A significant difference was observed in the average concentration of HERG channel protein between A431 cells, HaCaT cells and normal human skin tissue (49.7114 ± 3.55696 pg/ml, 35.7471 ±4.14696 pg/ml, 36.8857 ± 3.47810 pg/ml, all P < 0.05). Conclusions The block of voltage-gated potassium channel could inhibit the proliferation of A431 cells and HaCaT cells, and the expression of voltage-gated potassium channel seems to be higher in human skin squamous cell carcinoma cells.

Objective To analyze the changes in number and biological ability of endothelial progenitor cells (EPCs) from peripheral blood of SLE patients. Methods Mononuclear cells (MNCs) were isolated by Ficoll density gradient centrifugation from peripheral blood of 20 female SLE patients and 20 healthy female controls. EPCs were identified by double staining using antibodies to CD34 and CD133, or antibodies to CD133 and vascular endothelial growth factor receptor 2 (VEGFR2). Phycoerythrin (PE) conjugated antiCD34, fluorescein isothiocyanate (FITC) conjugated anti-CD133 and APC conjugated anti-VEGFR2 antibodies were used in a three color flow cytometric analysis to determine the percentage of EPCs in peripheral MNCs.The proliferation and migration ability of EPCs were measured by MTT assay and modified millicell chamber assay, respectively. The adhesion activity of EPCs was evaluated by counting the number of adherent cells.Results The percentage and proliferation rate of EPCs in peripheral MNCs from female SLE patients were significantly lower than those from the healthy controls(4.49% ± 1.66% vs 20.81% ± 4.14%, 23.11% ± 3.16%vs 35.65% ± 1.74%, both P ＜ 0.01 ). The migration and adhesion ability of EPCs from SLE patients was impaired compared with those from the healthy controls (12.00 ± 2.12 vs 23.60 ± 3.0 cells/field, 22.43 ± 4.43vs 36.43 ± 3.69 cells/filed, both P ＜ 0.01 ). Conclusion There is a decrease in the number and an impairment in biological ability of EPCs in SLE patients.