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OBJECTIVE: To evaluate the application value of 40 Hz auditory event related potential(40 Hz AERP) in hearing assessment in workers exposed to noise by observing the consistency between pure tone audiometry(PTA) and 40 Hz AERP. METHODS: A total of 240 ears of 120 workers who exposed to noise with PTA high-frequency hearing threshold > 25 dB were selected as the research subjects using the convenient sampling method. The thresholds of PTA and 40 Hz AERP at different frequencies were investigated. According to the average hearing threshold of PTA language frequency, the workers were divided into normal hearing group and mild-, medium-, medium-severe-, severe-hearing loss groups, and the difference and correlation between the thresholds of 40 Hz auditory potential and PTA were analyzed. RESULTS: The response thresholds of 40 Hz AERP of 0.5, 1.0, 2.0 kHz in ears of normal hearing group, and mild-and moderate-hearing loss groups were higher than the PTA hearing threshold(P<0.01), while the 40 Hz AERP response thresholds of 0.5 kHz in the ears of medium-severe-and severe-hearing loss groups were lower than the hearing thresholds of PTA(P<0.05). The different value of the response threshold of 40 Hz AERP and PTA of 1.0 and 2.0 kHz in ears of normal hearing group was higher than 0.5 kHz(median: 25.0 vs 15.0 dBHL, 30.0 vs 15.0 dBHL, P<0.01). Except for 0.5 and 1.0 kHz of mild-hearing loss group, the different value of the response threshold of 40 Hz AERP and PTA in ears of the other hearing loss groups were lower than that of the normal hearing group(P<0.01). The 40 Hz AERP response threshold was frequency-specific and correlated well with PTA at the same frequency. The correlation coefficients of 0.5, 1.0 and 2.0 kHz were 0.744, 0.732 and 0.665 respectively(P<0.01). CONCLUSION: It is feasible to evaluate PTA in noise-exposed workers using 40 Hz AERP response threshold, but the 40 Hz AERP cannot completely replace PTA. The measurement frequency and the degree of hearing loss should be considered simultaneously.
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OBJECTIVE: To observe the clinical effect of multistep breathing training combined with acupoint plastering on the treatment of patients with occupational coal worker's pneumoconiosis(CWP). METHODS: Eighty cases of male occupational CWP patients were selected as the research subject using convenient sampling method. They were divided into control group(40 cases) and treatment group(40 cases) according to random number table method. The control group was given conventional treatment, while the treatment group received multistep respiratory training combined with acupoint plastering for 12 weeks based on conventional symptomatic treatment. Before and after treatment, clinical curative effect, pulmonary function, immune function, the total score of Chronic Obstructive Pulmonary Disease Assessment Test(CAT) Questionnaire and 6 minutes walk distance(6 MWDS) in two groups were observed. RESULTS: Before treatment, there was no statistical difference on forced vital capacity(FVC), ratio of forced expiratory volume in one second(FEV_1)/FVC, lymphocyte cluster of differentiation(CD) 4~+/CD8~+ ratio, percentage of natural killer cells(NK), total CAT scores and 6 MWD(P>0.05). After treatment, the FVC, FEV_1/FVC ratio and lymphocyte CD4~+/CD8~+ ratio increased [median: 78.3% vs 80.7%, 68.7% vs 72.5%, 1.16 vs 2.00, P<0.01], 6 MWD was increased [(430.6±45.9) vs(494.8±58.7) m, P<0.01], and CAT total score was decreased [(18.1±5.6) vs(15.5±5.3) points, P<0.01] in the treatment group compared with the control group. There was no significant difference in NK cell percentage between the two groups(P>0.05). CONCLUSION: Multistep respiratory training combined with acupoint plastering can alleviate the clinical symptoms such as cough, and shortness of breath of patients with CWP, improve their lung function, regulate the function of immunity, as well as improve sports endurance.
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Objective:To investigate the late effects induced by external ionizing radiation through long-term follow-up of the victims exposed to 60Co radiation source at " 4.26" accident in Henan in 1999, and to provide valuable experience in the radiological medicine. Methods:Medical observations of the clinical symptoms, signs, eye lens examination and previous medical history of the five exposed victims were performed and recorded. The changes of the laboratory routine examinations, immune function, thyroid function, reproductive hormone levels, tumor markers, radiation genetic indicators as well as ultrasound examination of thyroid, cardiac, reproductive system, electrocardiogram, chest CT were systematically reviewed.Results:The typical radiation-induced cataract was found in " Mei" 2-3 years after 60Co accidental irradiation. 13 years after irradiation, the cataract surgery and intraocular lens implantation in left eye were performed followed by the same operation in right eye in November 2019. Different degrees phacoscotasmus under the posterior capsule or equatorial part of the eyes were also found in the rest of victims. ECG result of " Mei" indicated myocardial ischemia 7 years after accident. " Tian" confirmed diagnosis coronary heart disease 12 years after irradiation, and the surgery about coronary angiography heart stent implantation was taken at 20 years after irradiation. Five victims showed increased serum total cholesterol and/or triglycerides, and 4 victims showed bilateral or unilateral common carotid atherosclerotic plaque formation. Higher levels of thyroid stimulating hormone (TSH) were observed in " Mei" at 11 years after the irradiation. The thyroglobulin antibody (TGA)and thyroid microsomal antibody (TMA) were obviously increased in " Yi" , accompanied by thyroid uneven found by ultrasound. The thyroid nodules in " Mei" and " Min" were observed at 15 years after irradiation. The diagnosis of diffuse large B cell lymphoma(DLBL) in " Tian" was confirmed at 13 years after irradiation. Slightly higher of Neuron-specific enolase(NSE) were found in " Tian" , " Min" and " Yi" . A small nodule was detected from chest CT of " Tian" . Most of the chromosome aberrations observed in peripheral blood lymphocytes from the victims were stable chromosomal aberration such as translocation (t) with a few dicentric chromosome (dic) and acentric fragment (ace) in " Wang" and " Tian" . Conclusions:Ionizing radiation can cause variable degrees of deterministic effects in lens, thyroid gland and cardiovascular circulatory system and stochastic effects such as neoplasm. The genetic damages will last long in the patients.
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Objective To explore whether low-dose occupational ionizing radiation exposure can affect the prevalence of lens opacity.Methods Annual occupational health checkup data of 1 007 radiation workers was taken from a provincial medical institution for the purpose of statistical analysis.Logistic regression analysis was used to estimate occupational exposure odds ratios (OR) of lens opacity,adjusted for age,gender and length of service.Eye lens opacity was grouped into cortical,nuclear and posterior subcapsular opacity according to the position of the opacity occurrence site.Opacity occurred in any one of the both eye lens was recorded as turbidity.Results Only 730 cases coupled with complete information could be used in the statistical analysis.The rate of lens opacity for all the radiation workers was 10.27％.The rates of lens opacity by exposure group were estimated to be 9.07％ for radiation diagnosis and therapy group,11.11％ for intervention group,18.18％ for nuclear medicine group,and 9.33％ for industrial application group,respectively.Compared with those in the radiation diagnosis and therapy group,the workers engaged in intervention medicine,or nuclear medicine,were more likely to suffer from the lens opacity in posterior subcapsular position.The OR and its 95％ confidence intervals were 3.00 (1.23-7.33),4.12 (1.68-10.11) for the workers in intervention medicine or nuclear medicine group.Conclusions Medical radiation workers,who were exposed to long-term low-dose of ionizing radiation,especially those who engaged in intervention or nuclear medicine,were at significantly higher risk to develop lens opacity.