{L-End}Objective To study the situation of occupational noise exposure and hearing loss in workers in petrochemical enterprises. {L-End}Methods A total of 2 052 workers from four large-scale petrochemical enterprises in China were selected as the research subjects using convenience sampling method. The noise-exposed level of job position was detected by individual noise dosimeters, and pure-tone audiometry of the workers was conducted. {L-End}Results The noise-exposed levels at various job positions in the workplace of the enterprises ranged from 83.2 to 86.7 dB(A), and 61.1% of the job positions had a cumulative noise exposure (CNE) > 95.0 dB(A) per year. The detection rate of high-frequency hearing loss was 12.6%(259/2 052) among the research subjects. The detection rate of speech frequency hearing loss was 5.5%(112/2 052) among the research subjects. The result of CNE stratified analysis showed that the detection rate of hearing loss at frequencies of 2.0, 3.0, 4.0, and 6.0 kHz, as well as high frequencies, gradually increased with increasing CNE (all P<0.05). {L-End}Conclusion The noise hazard in petrochemical enterprises is severe, and long-term occupational noise exposure can increase the risk of hearing loss among workers. Efforts should be made to strengthen noise control and hearing protection measures.

{L-End}Objective To estimate the number of workers with occupational noise-induced hearing loss (ONHL) in the manufacturing industry of China in 2020. {L-End}Methods Multiple data sources were integrated to collect information on workers in the manufacturing industry from the Occupational Diseases and Hazards Monitoring Information System under China Disease Prevention and Control Information System. The total number of workers was split based on age from the 2018 Fourth National Economic Census and the 2020 National Survey of Occupational Disease Hazards. Additionally, data on the prevalence of hearing loss in the general population was adjusted based on the age composition of Jilin Province, and noise prevalence was standardized based on the age composition of the employed population in the Seventh National Population Censu. Attribution fractions (AF) was estimated. The prevalence ratio (PR) was calculated by the prevalence of hearing loss in the occupational noise-exposed workers and general population. The proportion and attributable cases (AC) of ONHL cases in all hearing loss cases were estimated for occupational noise-exposed workers. The number of ONHL was estimated based on AF and the total number of workers with hearing loss. {L-End}Results In 2020, a total of 30 059 525 workers were exposed to occupational noise in the manufacturing industry in China, with noise-exposed prevalence and standardized noise-exposed prevalence of 28.94% and 28.52%, respectively. The prevalence of hearing loss among occupational noise-exposed workers increased with age, and a total of 8 054 789 workers suffered from hearing loss. Most of the cases were at the age between 45-<55 years old. The total PR and 95% uncertainty interval (UI) was 2.83 (2.58-3.06) and the total AF and 95%UI was 64.63% (61.22%-67.30%), and both peaks were in the age of 30-<45 years. The AC and 95%UI was 5 205 980 (4 930 620-5 420 345) persons, and most of the cases were at the age between 40-<55 years. {L-End}Conclusion Occupational noise poses a serious threat to the hearing health of workers in the manufacturing industry of China, especially among middle-aged and young adults.

OBJECTIVE To analyze the risks of prescription drugs sold online by drug retail enterprises， and to provide countermeasures and suggestions for risk prevention and control of prescription drugs sold online. METHODS The risk hierarchy structure model of prescription drugs sold online by drug retail enterprises was constructed by using analytic hierarchy process. Multiple rounds of risk research and judgment were carried out on 123 pairs of evaluation indicators by using Delphi expert survey method. The normalized weight calculation and consistency test of risk judgment matrix were carried out to perform fuzzy quantitative research. RESULTS The risk of prescription dispensing and review （6.48%）， the risk of drug first and prescription later （5.48%）， the risk of rational drug use guidance （4.99%）， the risk of buying drugs by abnormal channel （4.97%）， the risk of “first diagnosis， non-chronic disease and non-common disease” （4.43%）， and the quality and safety risk of returned drugs （4.34%） and the application risk of regulatory technology （4.06%） were high risks； the overall risk of drug retail enterprises （chain） selling prescription drugs online was 38.67%， and the overall risk of drug retail enterprises （individual） selling prescription drugs online was 61.33%， with a difference of 22.66% between them. CONCLUSIONS There were 7 high-risk indicators for prescription drugs sold online by drug retail enterprises. Among them， the risk of prescription dispensing and review， the risk of drug first and prescription later， and the risk of rational drug use guidance are the top three high-risk points. The risk of prescription drugs sold online by drug retail enterprises （individual） is higher than that of drug retail enterprises （chain）. It is recommended that regulatory authorities focus on and regulate the prescription drugs sold online by drug retail enterprises （individual）， and encourage drug retail enterprises （chain） to establish a systematic online sales process for prescription drugs； for high-risk points of prescription drugs sold online， it is recommended that regulatory authorities and drug retail enterprises focus on it and take effective risk prevention and control measures to ensure the safe use of prescription drugs by the general public.

Objective: To investigate the characteristics of asymmetric hearing loss in automobile manufacturing workers and the effect of occupational noise exposure on asymmetric hearing loss. Methods: A cross-sectional approach was used in this study. From March 2017 to February 2018, Subjects (7066) from four complete vehicle factories were given a pure tone audiometry (Hearing thresholds were measured at frequencies of 0.5, 1, 2, 3, 4 and 6 kHz in each ear) and were required to complete a health-related information questionnaire. According to the inclusion criteria, a total of 6339 workers were selected. The mean hearing thresholds for the left and right ears at overall frequencies were compared using the repeated means analysis of variance (ANOVA) test. The threshold differences at each frequency were compared using paired t tests. Results: The overall mean left minus right threshold difference across all frequencies was determined to be 0.58 dB, which met statistical significance (P<0.01) . Hearing threshold in the left ear was statistically significantly higher compared with the right ear at each frequency. The differences between binaural threshold shifts at each frequency among subjects with a asymmetry in terms of worse left ear and worse right ear were at the range of 6.17-9.87 dB and 6.39-10.92 dB, respectively. Hearing threshold in the left ear was statistically significantly higher compared with the right ear at only 2, 3 kHz of subjects with high-frequency hearing threshold shifts (HFHTs) more than 25 dB. Hearing threshold in the left ear was statistically significantly higher compared with the right ear at only 3 kHz of subjects with high-frequency hearing threshold shifts (HFHTs) more than 30 dB. With the increase of HFHTs, the proportion of subjects with a asymmetry at 2 and 3 kHz of more than 10 dB in terms of worse left ear and worse right ear increased. Conclusion The average hearing threshold of the left ear across overall frequencies is higher compared with the right ear, the proportion of the cases with a higher left ear hearing threshold is higher that that of the cases with a higher right ear hearing threshold. As hearing loss caused by occupational noise exposure getting worse, the proportion of the cases with a higher left ear hearing threshold and the cases with a higher right ear hearing threshold may tent to be the same.

Objective To explore the limits of fluid-inversion prepared diffusion weighted imaging (FLIPD) in detection of acute cerebral ischemic lesions.Methods From January 2012 to March 2014,forty-nine patients (33 males,16 females,age (55.6± 12.3) years) clinically diagnosed as transient ischemic attack (TIA) were included.Patients underwent brain MRI (conventional diffusion weighted imaging (DWI) and FLIPD) within 3 d after the onset of TIA.The detection ability of MRI with the two sequences was compared,and the relative signal intensity (rSI) and apparent diffusion coefficient (ADC) of acute ischemic lesions based on two sequences were compared.Kappa test and two-sample t test were used to analyze the data.Results A total of 87 acute ischemic lesions were detected in 21 patients by conventional DWI,and 54 were detected in 19 patients by FLIPD (Kappa=0.916,P＜0.05).The rSI of ischemic lesions on FLIPD was significantly lower than that on conventional DWI (1.37±0.22 vs 1.57±0.26;t=6.647,P＜0.001).The ADC value of ischemic lesions on FLIPD was slightly lower than that on conventional DWI:(0.54 ±0.10) ×10-3 mm2/s vs (0.57±0.13)×10-3 mm2/s (t=2.120,P＜0.05).The missed lesions on FLIPD were located in the white matter (n =18),cerebellum and brainstem (n =8),and the cortex (n =7).Conclusions A slight diffuse abnormality may be missed on FLIPD,so this method is not suitable for the detection of acute ischemic lesions.FLIPD technology still needs improvement.

Objective: ICMM occupational health risk assessment model was be used to evaluate the risk of a lead-acid battery enterprise. Methods: In November 2016, a lead-acid battery company in Jiangsu Province was selected as the research object. Based on the occupational health survey data and occupational hazard assessment reports, the ICMM risk assessment model was used to conduct occupational health risks in eight key positions of a lead-acid battery enterprise. The risk assessment results was verified by actual test results. Results: In the quantitative assessment model, the occupational health risk assessment results for the castings and welding positions exposed to lead smoke, and the occupational health risk assessment results for the grinding and dividing positions exposed to lead dust existed unacceptable risks. The occupational health risk assessment results for the ball-milled and plated positions exposed to lead dust existed tolerable risks. The occupational health risk assessment results for the lead-plated and soldered positions exposed to sulphuric acid pastes and acids existed potential risks. In qualitative evaluation matrix method, the occupational health risk assessment results for the castings and welding positions exposed to lead smoke, and the occupational health risk assessment results for the grinding and dividing positions exposed to lead dust existed high risks, the occupational health risk assessment results for other four key positions were considered to be with low risks. Conclusion The key control points for lead smoke in this enterprise were castings and welding positions; The key control points for lead dust were the grinding and separating brush positions. The quantitative assessment model and the qualitative assessment matrix method in the ICMM model were consistent with the actual test results in the eight health risk assessments of occupational hazards in key positions. Therefore, the method could be applied to the assessment of occupational health risks of the lead-acid battery enterprise. According to the results of the assessment, improvements could be made to high-risk positions and the concentration of occupational hazards in high-risk posts could be reduced to better protect the health of workers.

OBJECTIVE: To compare the applicability of three risk assessment methods on occupational health risk assessment of chemical harmful factors in lead-acid battery manufacturers. METHODS: The convenient sampling method was used to select six lead-acid battery enterprises as research subjects. The occupational health risks of jobs with lead smoke,lead dust and sulfuric acid were determined by contact ratio method,comprehensive index method( both are semiquantitative evaluation method) and qualitative risk assessment method. The assessment was carried out,and the obtained risk level was standardized as the risk ratio. The evaluation results of these three methods were compared. RESULTS: For occupational health risk levels of lead smoke,lead dust and sulfuric acid,the contact ratio assessment method were 2-4,and the comprehensive index method were 2-3. The risk ratios after standardization were consistent with the risk level of that before standardization. The result of the qualitative risk assessment method was 2-3,and the standardized risk ratio was 3-4. The risk ratio of each post after standardization increased by one level compared with the risk level before standardization. When( Exposure limit concentration,E)/( Occupational exposure limit,OEL) ≥ 2,the occupational health risk levels of lead smoke,lead dust of qualitative risk assessment method and the contact ratio method were completely consistent,both of which were high risk,which were higher than the medium risk result of the comprehensive index method. When E/OEL < 2,Kappa analysis results showed that the contact ratio method and the comprehensive index method were in good agreement( Kappa = 0. 84,P < 0. 01). The qualitative risk assessment method were inconsistent with the contact ratio method and the comprehensive index method( Kappa value were -0. 22 and -0. 24). CONCLUSION: For occupational health risk assessment of chemical harmful factors in lead-acid battery manufacturers,the comprehensive index method could be used to evaluate the comprehensive results of occupational disease hazard factors and OEL in workplace. A qualitative risk assessment method can be used for assessment without test method or OEL of occupational hazard factor.

Objective To investigate the effect of measuring value transfer for human serum samples assigned by the reference laboratory network on improving the trueness of seven enzyme activities in clinical laboratories,such as ALT,AST,GGT,LDH,CK,AMY and ALP.Methods Depending on the medical imtitutions at all levels contacted by 5 reference laboratories in North China,South China,East China and Southwest China,the corresponding clinical laboratory measuring value transfer/traceability network was established.The frozen human serum samples with good interehangeability and standard material characteristics,including calibrator,sample 1 and sample 2,were provided by Beijing Aerospace General Hospital,and were assigned by 5 reference labotatories in four regiom.These samples were sent to 48 clinical laboratories.These clinical laboratories measured sample 1 and sample 2 according to their standard operating procedures,and then measured.the two samples again after adjusting their measurement system by using the supplied calibrator.The changes of trueness of detection results in these laboratories were evaluated according to the WS/T 403-2012 standard,and the changes of consistency for ALT and AST before and after measuring value tramfer were investigated.Results The results of AMY,ALP,GGT,CK and LDH calibrator,sample 1 and sample 2 assigned by the established network were 138.7 U/L,278.5 U/L and 68.3 U/L,265.3 U/L,94.5 U/L and 134.4 U/L,195.8 U/L,89.0 U/L and 158.9 U/L,393.7 U/L,260.0 U/L and 645.3 U/L,and 302.0 U/L,250.0 U/L and 452.7 U/L,respectively.The percentages of sample 1 and sample 2 which met the bias requirements of the WS/T 403-2012 standard before measuring value transfer for AMY,ALP and GGT were 65.9％ and 61.0％,76.6％ and 78.7％,and 66.7％ and 70.8％,respectively,while after measuring value transfer,they were 89.2％ and 83.8％,86.7％ and 80.0％,and 85.4％ and 91.7％,respectively.The percentages of sample 2 which met the bias requirements of the WS/T 403-2012 standard before measuring value transfer for CK and LDH were 64.6％ and 58.3％,respectively,while after measuring value trander,they were 93.5％ and 84.8％,respectively.The coefficients of variation (consistency) of sample 1 and sample 2 for ALT and AST before measuring value tramfer were 12.9％ and 11.3％,and 10.2％ and 8.9％,respectively,while after measuring value transfer,they were 9.3％ and 8.2％,and 5.6％ and 5.9％,respectively.Conclusion The calibration of routine measurement systems based on the measuring value transfer for human serum samples assigned by the reference laboratory network may improve the comparability of 7 enzyme actvities measurement results in chnical laboratories at all levels obviously,which deserves to be further spread.

Objective To investigate the value of ionic-contrast esophagogram in diagnosis of intrathoracic anastomotic leakage after oesophagectomy.Methods The data of 728 patients suffered esophagectomy were retrospectively collected.723 patients without clinical manifestations of anastomotic leakage were divided into group A(esophagogram before eating,n=465) and group B(non-esophagogram before eating,n=258).The incidence of anastomotic leakage was compared between the two groups.Results The discovery rates of anastomotic leakage in group A and B were 0.43%(2/465) and 0.78%(2/258),respectively,the difference was no statistically significant between the two group(P=0.55).The total incidence rates of anastomotic leakage in group A and B were 0.65%(3/465) and 0.78%(2/258),respectively,the difference was no statistically significant between the two groups(P=0.84).5 patients with clinically suspected anastomotic leakage,all had loculated pleural effusion,4 cases had fever,and 2 cases had abnormal chest drainage.Finally,4 cases(80%) were confirmed to be anastomotic leak by esophagogram.Conclusion Routine ionic-contrast esophagogram before eating do not improve intrathoracic anastomotic leakage detection rate after esophagectomy,but when patients have fever,loculated pleural effusion and abnormal chest drainage,esophagogram is necessary and can improve the detection rate of esophageal anastomotic leak.CT radiography may detect smaller anastomotic leakage than conventional esophagogram.

OBJECTIVE:To provide reference for rational drug use in the clinic. METHODS:Irrational medication orders eval-uated by the Affiliated Cancer Hospital of Zhengzhou University during Oct. 2014 to Sep. 2015 were arrangemented,summarized and analyzed. RESULTS:A total of 515 inpatient medical records were reviewed and analyzed,among which there were 165 unrea-sonable medical records and 185 irrational medication orders. Irrational medical records of general surgery department were the most(38 items,accounting for 23.03%). Irrational drug use mainly included irrational usage and dosage(80.00%),drug use with-out indications or not suit indications (7.57%),inappropriate solvent selection (4.86%). Including 66.22% of single overdose, 18.92% of longer medication duration. CONCLUSIONS:There are many irrational medical orders which should be standardized in our hospital,especially overdose and longer medication duration,which increase financial burden of patient. Pharmacists should strengthen communication with clinicians,and hold rational drug use trainings regularly base on the types of the irrationality. These can help to improve rational drug use and guarantee the safety of drug use.