Objective To investigate the current status of radiation protection in non-medical radiation workplaces in Yantai, China, and to provide a scientific basis for occupational health management in non-medical radiation workplaces. Methods Non-medical radiation workplaces in Yantai were investigated using a questionnaire survey in 2022, including radiation source term, occupational health examination, personal dose monitoring, personal protective equipment, and radiation protection testing workplaces. Data were entered by a double-entry method and then analyzed. Results There were 56 non-medical radiation workplaces in Yantai, covering manufacturing, nonferrous metal ore mining, nuclear power plant, transportation, and technical services. There were 0 Class I radiation device, 150 Class II radiation devices, and 10 Class III radiation devices; there were 80 Class I radiation sources, 16 Class II radiation sources, 14 Class III radiation sources, 62 Class IV radiation sources, and 135 Class V radiation sources. There were 998 radiation workers, with an occupational health examination rate and personal dose monitoring rate of 98.3%. Among the 56 non-medical radiation workplaces, 47 (83.9%) were equipped with radiation protection monitoring instruments, 24 (51.1%) workplaces had verified the radiation protection monitoring instruments, with 2017 personal dose monitoring instruments and 2327 personal protective equipment in place, 42 (75%) workplaces carried out occupational health assessments, 44 (78.6%) workplaces carried out self-detection, and 53 (94.6%) workplaces carried out entrusting detections (monitoring pass rate: 100% [53/53]). The declaration rate of occupational hazard items was 87.5% (49/56). Conclusion There is still a gap between the current status and the requirements in the national regulations and standards regarding radiation protection in non-medical radiation workplaces. Therefore, the supervision and management of non-medical radiation workplaces should be further strengthened, especially the configuration and verification of radiation protection monitoring instruments.

Objective:To establish and verify a diagnostic model for distinguishing multiple sclerosis (MS) from other neurological diseases with similar symptoms by usingcerebrospinal fluid oligoclonal band (CSF-OCB)combined with IgG intrathecal synthesis indicators and biochemical markers.Methods:Multiple sclerosis (MS) patients admitted to the Neurology Department of Beijing Tiantan Hospital affiliated with Capital Medical University from January 2014 to December 2022 were selected as the case group, while patients with similar neurological symptoms were selected as the control group. Using the case-control study design, a retrospective analysis was conducted on the detection of age, gender, oligoclonal bands in cerebrospinal fluid, IgG intrathecal synthesis indicators and biochemical indicators for all study subjects. The differential diagnosis model was determined by the multiple logistic regression analysis, and the receiver operating characteristic (ROC) curve was used to analyze the diagnostic efficiency of the differential diagnosis model for neurological diseases with similar symptoms to MS and other conditions.Results:This study included 167 patients in the case group and 335 patients in the control group, of which 128 patients in the case group and 265 patients in the control group were used to construct the model, and 39 patients in the case group and 70 patients in the control group were used for model validation. The differential diagnostic model constructed by a multivariate logistic regression model was Y=0.871×CSF-OCB-0.051×CSFprotein-0.231×CSFchloride+1.183×gender-0.036×LDH+35.770. The model showed that the area under the curve, sensitivity and specificity were respectively 0.916, 87.3% and 87.6%. The Delong test results showed that the diagnostic efficacy of the model was significantly different from OCB, IgG intrathecal synthesis indicators, and OCB combined with IgG intrathecal synthesis indicators ( P<0.05). The new model validation showed that the actual diagnostic consistency rate for the MS group was 84.6%, while the actual diagnostic consistency rate for the control group was 90.0%. Conclusion:This study combines OCB, IgG intrathecal synthesis indicators, and biochemical indicators to establish a diagnostic prediction model for neurological diseases with similar clinical symptoms in MS. This model may have good differential diagnostic value and can better assist clinical diagnosis in the early stages of disease progression in MS patients.

Objective:To establish and verify a diagnostic model for distinguishing multiple sclerosis (MS) from other neurological diseases with similar symptoms by usingcerebrospinal fluid oligoclonal band (CSF-OCB)combined with IgG intrathecal synthesis indicators and biochemical markers.Methods:Multiple sclerosis (MS) patients admitted to the Neurology Department of Beijing Tiantan Hospital affiliated with Capital Medical University from January 2014 to December 2022 were selected as the case group, while patients with similar neurological symptoms were selected as the control group. Using the case-control study design, a retrospective analysis was conducted on the detection of age, gender, oligoclonal bands in cerebrospinal fluid, IgG intrathecal synthesis indicators and biochemical indicators for all study subjects. The differential diagnosis model was determined by the multiple logistic regression analysis, and the receiver operating characteristic (ROC) curve was used to analyze the diagnostic efficiency of the differential diagnosis model for neurological diseases with similar symptoms to MS and other conditions.Results:This study included 167 patients in the case group and 335 patients in the control group, of which 128 patients in the case group and 265 patients in the control group were used to construct the model, and 39 patients in the case group and 70 patients in the control group were used for model validation. The differential diagnostic model constructed by a multivariate logistic regression model was Y=0.871×CSF-OCB-0.051×CSFprotein-0.231×CSFchloride+1.183×gender-0.036×LDH+35.770. The model showed that the area under the curve, sensitivity and specificity were respectively 0.916, 87.3% and 87.6%. The Delong test results showed that the diagnostic efficacy of the model was significantly different from OCB, IgG intrathecal synthesis indicators, and OCB combined with IgG intrathecal synthesis indicators ( P<0.05). The new model validation showed that the actual diagnostic consistency rate for the MS group was 84.6%, while the actual diagnostic consistency rate for the control group was 90.0%. Conclusion:This study combines OCB, IgG intrathecal synthesis indicators, and biochemical indicators to establish a diagnostic prediction model for neurological diseases with similar clinical symptoms in MS. This model may have good differential diagnostic value and can better assist clinical diagnosis in the early stages of disease progression in MS patients.

Objective:To investigate epidemiological characteristics and influencing factors on dust-exposed working years of pneumoconiosis cases in Yantai.Methods:In January 2020, By Cluster sampling way, Using descriptive statistics to analyze dust-exposed working years of the reported 3307 new cases of pneumoconiosis from 2009 to 2019 in Yantai. Analyzing the variation trends by the chi-square trend test. Analyzing single fator by chi-square test. Using multiple classification Logistic Regression analysis to analyze multiple influencing factors.Results:The dust-exposed working age of pneumoconiosis cases decreased by years ( P<0.05) . The starting age of dust exposure of cases increased year by year, while positively correlated with the dust-exposed working age ( r=-0.217, P<0.05) . The years of dust exposure, starting age of dust exposure, industry, type of economy and scale of enterprise were main influence factors on the dust-exposed working age of pneumoconiosis cases. Conclusion:We should strengthen the management on prevention and control condition of pneumoconiosis in metal smelting and processing industry and privately-owned, small and micro enterprises, and pay attention to workers starting exposed to dust in the age of ≥28 years old.

Objective:To investigate epidemiological characteristics and influencing factors on dust-exposed working years of pneumoconiosis cases in Yantai.Methods:In January 2020, By Cluster sampling way, Using descriptive statistics to analyze dust-exposed working years of the reported 3307 new cases of pneumoconiosis from 2009 to 2019 in Yantai. Analyzing the variation trends by the chi-square trend test. Analyzing single fator by chi-square test. Using multiple classification Logistic Regression analysis to analyze multiple influencing factors.Results:The dust-exposed working age of pneumoconiosis cases decreased by years ( P<0.05) . The starting age of dust exposure of cases increased year by year, while positively correlated with the dust-exposed working age ( r=-0.217, P<0.05) . The years of dust exposure, starting age of dust exposure, industry, type of economy and scale of enterprise were main influence factors on the dust-exposed working age of pneumoconiosis cases. Conclusion:We should strengthen the management on prevention and control condition of pneumoconiosis in metal smelting and processing industry and privately-owned, small and micro enterprises, and pay attention to workers starting exposed to dust in the age of ≥28 years old.

Objective: To understand influencing factors on workers' personal protective equipment (PPE) usage, and provide a basis for standardizing the PPE use in the city. Methods: The basic information of workers exposed to occupational hazards in a municipal area was imported into SPSS 18.0 and numbered sequentially in May 2018. A simple random sampling method was used to select 1 678 workers as the research object, and then a questionnaire survey was conducted from June to July 2018. In the valid questionnaires collected, workers who self-rated as "full-time correct use of PPE" and were approved by occupational health managers of employing units were included in the "correct use group" and others in the "incorrect use group". χ² test was used to analyze the PPE use of different factors, and binary unconditional logistic regression analysis was used to analyze the influencing factors. Results: 1547 valid questionnaires were collected in this study, including 803 workers correctly used PPE at full time (51.9%) , and other workers never used or occasionally used PPE. There were statistical difference of PPE usage rate among workers of different sex, industry and wage type (P<0.05) . Occupational health supervisors setting example in PPE usage (β=0.368) , workmates using PPE correctly and reminding PPE usage (β=0.891) , posting warning specifications of occupational hazards (β=0.361) , setting up "safe man" at the entrance of workshop (β=0.585) , WeChat and other new media on occupational health knowledge propaganda (β=0.536) , punishing incorrect usage of PPE (β=0.252) 、sex (β=-0.512) and wage type (β=-0.203) are influencing factors affecting the usage of PPE. Conclusion PPE usage rate of the occupational population in the city is still fairly low, and the PPE usage is influenced by a variety of factors. Comprehensive measures should be taken by employers to ensure using PPE to protect workers' occupational health.

Objective To investigate the clinical effects of treating traumatic lesions of the popliteal artery by staged stretching.Methods From July 2011 to March 2016,29 patients with traumatic lesion of the popliteal artery underwent staged stretching after direct end to end anastomosis at Department of Orthopaedics,The 9th People's Hospital of Wuxi.They were 19 males and 10 females,with a mean age of 38.3 years (range,from 16 to 61 years).The average length of popliteal artery lesions was 3.7 cm (range,from 2 to 5 cm).After the keen joint was immobilized at flexion by external fixation,direct end to end anastomosis was performed with a proper segmental vascular freedom.From 4 weeks after operation,the popliteal artery was stretched stage by stage to its original length by gradual adjustment of the external fixation till the knee joint was fully extended.The color,skin temperature,pulp tension and capillary reaction of the toes were closely observed after surgery.CT angiography (CTA) was performed 6 months after surgery.The active range of motion was assessed at 12 months after surgery for the knee and ankle joints on the injured limb.Results All the patients were available for an average follow-up of 2 years (range,from 1 to 3 years).Blood supply was good for all the affected limbs.The staged stretching of the popliteal artery resulted in no rupture of any anastomotic stoma or no thrombus.CTA at 6 months after surgery showed fine patency of the popliteal artery and no formation of false aneurysm or arteriovenous fistula.At 12 months after surgery,the knee function was excellent in 15 cases,good in 10 and fair in 4;the ankle function was excellent in 18 cases,good in 8 and fair in 3.Conclusion Staged stretching is a safe,convenient and effective treatment of traumatic lesions of the popliteal artery.

Objective To analyze the therapeutic effect of Masquelet technique in the treatment of bone defects.Methods From January 2008 to December 2014,20 patients with bone defects were treated by Masquelet technique.There were 15 males and 5 females,from 18 to 69 years of age (average,38.4 years).Four cases had open bone defects and 16 infectious ones.At the first stage,radical debridement of the bone defects and soft tissue was conducted via conventional approaches.The bone defects ranged from 2 to 9 cm,averaging 6.1 cm.At the second stage,internal fixation was applied in 18 cases and external fixation in 2.The interval from the second stage to the first stage operation ranged from 6 to 23 weeks (average,11.5 weeks).The healing of bone defects and the functional recovery of adjacent joint were evaluated by Paley scoring at the last follow-up.Results The 20 patients were followed up for 12 to 50 months (average,19.7 months) after the second stage operation.All the patients obtained uneventful wound healing and control of infection after the first stage operation except the one with infectious defects who had to receive 2 operations to control the infection at the first stage operation.At the second stage operation,obvious injury and defect of the induced membrane occurred in 4 cases.All the patients achieved clinical healing of bone defects after 3 to 6 months (average,4.8 months).The bone defect healing was graded as excellent in all.After bone healing,all the patients resumed weight-bearing activities,with no breakage or infection of fixators,or recurrence of infection.By the Paley scoring at the last follow-up,the functional recovery of the adjacent joint was excellent in 8 cases,good in 10 and fair in 2,yielding an excellent and good rate of 90.0％.Conclusion As a kind of modified free bone grafting,Masquelet technique has advantages of simplicity,limited complications,a high rate of healing,and good control of bone infection.

Objective To investigate the carrying status and characteristics of Clostridium difficile isolated from infants.Methods Two hundred and thirty-eight stool specimens were collected from infant younger than 1 year old,that were hospitalized or outpatient from August to November 2015.Immunochromatography targeted GDH and toxin A&B of C.difficile was used for C.difficile screening,and those positive specimens were inoculated in CDIF and anaerobic culture.C.difficile isolates were genotyped by using slpA sequence typing (slpA ST),and tcdA,tcdB,cdtA and cdtB of C.difficile isolates were detected by PCR.Results Fifty C.difficile strains were isolated from 238 stool samples,and the isolated rates of C.difficile from <3 months,3 months to <6 months,and 6 months to 1 years old groups were 9.3%,17.6% and 27.3%(χ2=6.940,P=0.031<0.05),respectively.52.0%(26/50) of the C.difficile isolates were toxigenic,and 69.2% (18/26) toxigenic isolates harbored tcdA+tcdB+cdtA-cdtB-.Fifty C.difficile isolates were genotyped as 11 slpA STs,slpA ST fr-02 and kr-02 were the commonest genotypes in toxigenic C.difficile isolates;however,that was slpA ST xr-03 in non-toxigenic isolates.Conclusion High C.difficile carriage is found in infants younger than 1 year old,and more than half of C.difficile isolates are toxigenic.Most of toxigenic isolates harbored toxin A and B.The genotype of C.difficile isolates is different between toxigenic isolates and non-toxigenic isolates.

Objective To construct a large animal model of ischemic heart disease induced by acute myocardial infarction (AMI) . Methods Male Diannan Mini-pigs were selected (n=8), weight 20 ± 4 Kg. After general anesthesia and endotracheal intubation, blood pressure and electrocardiograph were monitored. Parasternal incision was taken and thoracotomyv was performed at 4th-to-5th intercostalgap. Pericardium was opened and left anterior descending artery was ligated. Echocardiography was performed at baseline, postoperative 28 and 60 day. Euthanasia and heart explanted was conducted at 60 day of experimental pig. After gross examination of the heart, the histological examination was used to assess myocardial infarction by using H&E staining. Results All of the pigs were presented with ventricular arrhythmias in varying degrees after ligation of the left anterior descending artery, of whom 2 died of refractory ventricular fibrillation, the mortality was 25%. Echocardiography assessment showed the loss left ventricular function, the thinning of left ventricular apical and the enlargement of left ventricule. Histological examination revealed that myocardial fibrosis and fibrous scar were formed in myocardial infarction area. Conclusion The ligation of left anterior descending artery through thoracotomy under direct vision is a reliable strategy for construction of AMI porcine model and the experimental porcine can develop ischemic cardiac dysfunction progressively.