Objective To evaluate the role of distortion product otoacoustic emissions (DPOAE) testing in evaluating early hearing loss among noise-exposed workers. Methods A total of 174 noise-exposed workers in a metal shipbuilding enterprise were selected as the research subjects by the convenience sampling method. Pure tone audiometry (PTA), DPOAE and the level of noise exposure were conducted on the workers. The rank correlation analysis was used to analyze the correlation between DPOAE amplitude and PTA threshold. The multilevel model was used to analyze the effects of gender, age, noise exposure intensity, cumulative noise exposure (CNE), hearing loss classification and PTA threshold on DPOAE results. Results At the frequencies of 0.50, 1.00, 2.00, 3.00, 4.00, 6.00 and 8.00 kHz, the DPOAE amplitude was negatively correlated with the PTA threshold (rank correlation coefficients were -0.12, -0.48, -0.47, -0.18, -0.23, -0.44, -0.19, respectively, all P<0.01). At the most frequencies, DPOAE amplitude was negatively correlated with age and CNE (all P<0.05). The results of multilevel model analysis showed that there were significant differences in DPOAE amplitudes at certain frequencies across gender, age, noise intensity, CNE, and hearing loss classification (all P<0.05). Significant differences in DPOAE responses were found among different CNE and hearing loss groups (all P<0.01). Conclusion DPOAE testing can objectively reflect the hearing status of noise-exposed workers and could be considered for inclusion in routine hearing monitoring to facilitate early detection of noise-induced hearing loss.

Objective To analyze the quality of 22 batches of Fritillariae thunbergii bulbus Formula Granules from 12 different manufacturers by using water-extraction reference substance of Fritillariae thunbergii bulbus(ZBM ERS ST)and water-extraction reference substance of Fritillariae hupehensis bulbus(HBBM ERS ST)as references.Methods Ethyl acetate-methanol-triethylamine-water(17∶1∶1∶0.5)was used as the developing solvent for high-performance thin-layer chromatography(HPTLC)fingerprint analysis.The high-performance liquid chromatography(HPLC)fingerprint analysis was performed on a Agilent Eclipse XDB-C18 column(4.6 mm×250 mm,5 μm)with the gradient mobile phase consisted of acetonitrile-0.03%diethylamine solution.The column temperature was set at 25℃and evaporative light-scattering detector was used.The determination was conducted according to standard test method for measurement of Fritillariae thunbergii bulbus Formula Granules(Guangdong PFKL00117).Results The results of HPTLC and HPLC analysis showed that there are significant differences among the 22 batches of Fritillariae thunbergii bulbus Formula Granules.There were 4 batches of Fritillariae thunbergii bulbus Formula Granules from 3 manufacturers among them showed fingerprint characteristics of Fritillariae hupehensis bulbus.The total amount of peimine and peiminine in the remaining 18 batches of Fritillariae thunbergii bulbus Formula Granules was 0.291-3.179 mg·g-1,which were quite different.Conclusion Currently,the quality of Fritillariae thunbergii bulbus Formula Granules on the market varies greatly.Standardized water-extract reference substance has better applicability for the analysis of the quality of Fritillariae thunbergii bulbus Formula Granules than the control medicinal materials.

ObjectiveTo analyze the spectrum distribution characteristics of high-intensity productive noise in key industries in Guangdong Province. Methods A total of 2 806 enterprises in 21 prefecture-level cities in Guangdong Province were selected as the study subjects using the stratified sampling method. On-site investigations were conducted in workplaces. Noise in workplaces and work-sites, and the noise spectrum of the workplaces with sound pressure level ≥85.0 dB(A) were detected. Results The noise of a total of 23 076 workplaces and 20 969 work sites from 30 key industries were monitored. The median (M) and 25th and 75th percentiles (P₂₅, P₇₅) of workplace sound pressure level were 82.3 (78.6, 86.5) dB(A). The rate of the noise exceeded national standard was 30.4%. The sound pressure level M (P₂₅, P₇₅) of work-site was 78.6 (70.0, 83.5) dB(A). The rate of the noise exceeded national standard was 18.0%. Workplace noise and work site noise were positively correlated (Spearman correlation coefficient=0.86, P<0.01). The rate of the noise exceeded national standard was 46.5% in key work sites where the rate of noise exceeded the national standard was ≥25.0%, and corresponding rate of the workplace noise exceeded national standard was 58.1%. The noise spectrum result of 5 636 workplaces sound pressure level>85.0 dB(A) showed that most of the noise source was from grinding machines (441 cases), and the highest average sound pressure level of noise source was from screening machines [93.0 dB(A)]. Cluster analysis results showed that the main noise sources could be divided into three categories, including wideband noise with levels >80.0 dB in all frequency bands except 8 000.0 Hz, medium-high-frequency noise with the highest sound pressure level at 1 000.0, 2 000.0, and 4 000.0 Hz and low frequencies <75.0 dB, and medium-low-frequency noise below 500.0 Hz with sound pressure level >85.0 dB. Conclusion The rate of the noise exceeded national standard in workplace of key industries in Guangdong Province is high, involving a wide range of industries, with high sound pressure levels and obvious spectrum characteristics of corresponding noise sources. Corresponding noise control strategies can be formulated based on different spectrum characteristics and magnitudes.

Objective     To identify the heart sounds of aortic stenosis by deep learning model based on DenseNet121 architecture, and to explore its application potential in clinical screening aortic stenosis. Methods      We prospectively collected heart sounds and clinical data of  patients with aortic stenosis in Tianjin Chest Hospital, from June 2021 to February 2022. The collected heart sound data were used to train, verify and test a deep learning model. We evaluated the performance of the model by drawing receiver operating characteristic curve and precision-recall curve.  Results     A total of 100 patients including 11 asymptomatic patients were included. There were 50 aortic stenosis patients with 30 males and 20 females at an average age of 68.18±10.63 years in an aortic stenosis group (stenosis group). And 50 patients without aortic valve disease were in a negative group, including 26 males and 24 females at an average age of 45.98±12.51 years. The model had an excellent ability to distinguish heart sound data collected from patients with aortic stenosis in clinical settings: accuracy at 91.67%, sensitivity at 90.00%, specificity at 92.50%, and area under receiver operating characteristic curve was 0.917.   Conclusion     The model of heart sound diagnosis of aortic stenosis based on deep learning has excellent application prospects in clinical screening, which can provide a new idea for the early identification of patients with aortic stenosis.

Objective: To analyze the status of noise hazard in workplace of key industries in Guangdong Province. Methods: A total of 1 061 enterprises from 14 key industries in 21 prefecture-level cities in Guangdong Province were selected as the research subjects using stratified sampling method. The occupational health survey was carried out, and the noise intensity in the workplace was detected. Results: There were 12 606 workplaces and 5 570 work sites involved among 1 061 enterprises. The median and the 0-100th percentile value ［M (P₀-P₁₀₀)］ of noise intensity in workplace were 82.6 (46.5-112.6) dB(A), and 35.03% of the workplace exceeded the national noise intensity standard. The regions and industry with the highest rate of noise exceeded the national noise intensity standard in workplace were in the northern part of Guangdong and the stone processing industry respectively. The M (P₀-P₁₀₀) of noise intensity in the work sites was 83.7 (47.5-106.2) dB(A), and 36.00% of the work sites exceeded the national noise intensity standard. The regions and industry with the highest rate of noise exceeded the national noise intensity standard in work sites were in the Pearl River Delta region and the ferrous metal mining and dressing industry respectively. The rate of noise protection facilities setting was 66.45%, and the validity of personal protection was 61.73%. The occupational medical examination was performed in 73.24% of the research subjects, and 3.25% of the result was abnormal. The industry with the highest occupational medical examination rate was nonferrous metal smelting and rolling processing, and the industry with the highest abnormal rate of occupational medical examination was stone processing industry. Conclusion: Noise hazards in workplaces of key industries in Guangdong Province are relatively severe, necessitating strengthened supervision and management, noise control measures, and efforts to reduce noise exposure levels in workplaces and work sites.

{L-End}Objective To analyze the characteristics of hearing loss and the influencing factors of high-frequency hearing loss (HFHL) among noise-exposed workers in an urban rail transit enterprise over five consecutive years. {L-End}Methods A total of 1 268 noise-exposed workers, who exposed to the average noise intensity of <85.0 dB(A), in an urban rail transit enterprise was selected as the research subjects using a judgment sampling method. The pure-tone audiometry results from 2019 to 2023 were collected to analyze the result of hearing loss. The influencing factors of HFHL (average hearing threshold ≥40.0 dB at high frequencies in both ears) were analyzed using the generalized estimating equations (GEE). {L-End}Results The detection rates of threshold elevations at frequencies of 0.5-6.0 kHz increased with increasing frequency from 2019 to 2023 (all P<0.01), with the highest detection rate at 6.0 kHz. The detection rate of speech frequency hearing loss (hearing threshold weighted value≥26.0 dB in the better ear) was 0.1%, 0.0%, 0.4%, 0.2%, and 0.2%, respectively. The detection rate of HFHL from 2019 to 2023 was 2.4%, 2.8%, 2.8%, 2.1%, and 2.8%, respectively. The GEE analysis results showed that the risk of HFHL of the workers in 2022 and 2023 was lower than that in 2019 (all P<0.01), with the odds ratios and 95% confidence intervals ［OR (95%CI)］ of 0.57 (0.41-0.81) and 0.65 (0.48-0.87), respectively. The risk of HFHL was higher among vehicle maintenance worker than train drivers (P<0.05), with OR (95%CI) of 2.37 (1.18-4.77). The risk of HFHL increased with age and length of service among the workers (all P<0.05), with the OR (95%CI) of 2.05 (1.22-3.46) and 1.69 (1.12-2.54), respectively. No interaction was found between type of job and age, type of job and length of service, or age and length of service in the risk of HFHL among the research subjects(all P<0.05). {L-End}Conclusion Noise exposure below the national occupational exposure limits can lead to hearing loss in noise-exposed workers of urban rail transit enterprises, possibly affecting the hearing threshold at 6.0 kHz first. The influencing factors for HFHL in workers of rail transit are age, length of service, and type of job. There is a dose-effect relationship with age and length of service.

Objective:To investigate the application of "micro ward" teaching based on the concept of dedicated education units (DEU) in the standardized training of neurosurgery residents.Methods:The 22 neurosurgery residents enrolled in 2021 for standardized training were assigned to the control group with traditional teaching method. The 24 neurosurgery residents enrolled in 2022 were assigned to the observation group with the "micro ward" teaching method based on the DEU concept. The theoretical knowledge and operational skill scores, clinical thinking ability, and teaching satisfaction were compared between the two groups of students before and after the training. SPSS 21.0 was used to perform chi-square test, Z test and t test. Results:The observation group had higher scores in terms of surgical skills [(190.63±4.35) vs. (86.79±4.82)] and case analysis [(190.54±5.06) vs. (86.13±5.35)] than the control group ( P<0.05). The scores were higher in the observation group than in the control group in terms of broadening thinking, overall thinking, curiosity, and cognitive maturity after training ( P<0.05). The observation group had a significantly higher proportion of students who were satisfied with standardized neurosurgery training teachers, teaching methods, and teaching results than the control group ( P<0.05). Conclusion:The application of "micro ward" teaching based on the concept of DEU in the standardized training of neurosurgery residents can effectively improve the clinical practice ability and professional quality of trainees, cultivate their specialized clinical thinking, enhance their independent learning ability, and improve the training quality. Therefore, this teaching method is worth promoting.

Background Wearing anti-vibration gloves is a simple and effective way to prevent hand-arm vibration disease. The requirements for vibration damping gloves are varied by types of operations exposed to vibration. Objective To study the vibration attenuation and dexterity of different types of protective gloves, and to provide reference for scientific wearing of vibration damping gloves for people working with vibration exposure. Methods Nine kinds of common protective gloves (A and B were dipping gloves; C, D, and E were rubber gloves; F and G were textile and fabric gloves; H was cotton gloves; I was leather gloves) used by workers exposed to vibration in 28 factories in Guangdong Province were selected as research objects by typical case sampling method, and the basic parameters of included protective gloves were investigated and measured. According to ISO 10819:2013, a glove vibration transmissibility (GVT) test system was used to detect the vibration transmissibility values and analyze vibration attenuation characteristics of the subjects wearing different protective gloves. The dexterity was tested by Minnesota Manual Dexterity Test. Pearson test was used to analyze the correlations among glove thickness, vibration transmissibility, dexterity score, and grip strength score. Results For rubber gloves (C, D, and E), the associated average adjusted vibration transmissibility at middle and low frequencies \begin{document}$ {\overline T _{\text{M}}} $\end{document} and average adjusted vibration transmissibility at high frequency \begin{document}$ {\overline T _{\text{H}}} $\end{document} were lower than those of other gloves (0.89-0.91 and 0.59-0.80 respectively), the vibration transmissibility values of 50-200 Hz frequency band was 0.81-0.97, and the vibration transmissibility values of 315-1250 Hz frequency band decreased with the increase of frequency (the minimum value was 0.13). For other types of gloves (A, B, F, G, H, and I), the \begin{document}$ {\overline T _{\text{M}}} $\end{document} and \begin{document}$ {\overline T _{\text{H}}} $\end{document} were 0.95-0.98 and 1.03-1.11 respectively, the vibration transmissibility values of 50-200 Hz frequency band was 0.96-1.02, and the vibration transmissibility values of 400-1250 Hz frequency band increased (the maximum value was 1.29). The \begin{document}$ {\overline T _{\text{M}}} $\end{document}, \begin{document}$ {\overline T _{\text{H}}} $\end{document}, and vibration transmissibility values of 40-1250 Hz frequency band of rubber gloves with double-layer protective materials (C, D, and E) were significantly lower than those of gloves with single-layer protective materials. But the \begin{document}$ {\overline T _{\text{M}}} $\end{document} and \begin{document}$ {\overline T _{\text{H}}} $\end{document} of gloves of other types with double-layer materials (F, H, and I) were still greater than 0.9 and 1.0 respectively. Compared with single-layer protective materials, the gloves of other types with double-layer materials showed no significant changes in the vibration transmissibility values of 25-200 frequency band (0.91-1.06), and an increase in the vibration transmissibility values of 250-630 Hz frequency band (the maximum value was 1.22). The dexterity scores and grip strength scores of dipping gloves (A and B) were the lowest. Rubber gloves C had the highest dexterity score and grip strength score. The thickness of protective gloves was negatively correlated with the vibration transmissibility values, and positively correlated with the dexterity score and the grip strength score (P < 0.05). The vibration transmissibility value was negatively correlated with the dexterity score and the grip strength score (P < 0.05). Conclusion Among the 9 kinds of gloves, cotton gloves and leather gloves have no damping effect. Rubber gloves have certain vibration reduction effect, and the vibration reduction effect on high frequency band is better than that on low frequency band. The thicker the damping material is, the better the damping effect is, but the less the dexterity is. Appropriate damping gloves should be selected according to actual vibration operations.

Objective:To explore the influence of blood pressure during peri-thrombolysis period (from admission to 24 h after thrombolysis) in intracranial hemorrhage, improvement of neurological function, primary endpoint event (recurrence of symptomatic stroke) and secondary endpoint events (complex cardiovascular and cerebrovascular events, and all-cause death) in patients with acute ischemic stroke.Methods:A total of 422 patients with acute ischemic stroke who underwent intravenous thrombolysis with alteplase during hospitalization at National Center for Stroke in Lianyungang from January 2015 to March 2019 were followed up for 90 d. According to the quintile of mean systolic and diastolic blood pressures during peri-thrombolysis period, they were divided into group of blood pressure <130.00 mmHg (Q1), group of blood pressure of 130.00-140.49 mmHg (Q2), group of blood pressure of 140.50-147.99 mmHg (Q3), group of blood pressure of 148.00-158.00 mmHg (Q4), and group of blood pressure >158.00 mmHg (Q5), and group of blood pressure <71.30 mmHg (G1), group of blood pressure of 71.30-76.19 mmHg (G2), group of blood pressure of 76.20-81.89 mmHg (G3), group of blood pressure of 81.90-90.79 mmHg (G4), group of blood pressure >90.79 mmHg (G5). Univariate and multivariate Logistic regression analyse were used to evaluate the relations of blood pressure with postoperative intracranial hemorrhage and neurological function improvement. Kaplan-Meier curve, Log-rank test and multivariate Cox proportional risk model were used to evaluate the relations of blood pressure with primary endpoint event and secondary endpoint events.Results:(1) After adjusting for confounding factors, multivariate Logistic regression analysis showed that the risk of postoperative intracranial hemorrhage in patients from Q2 was significantly lower than that in patients from Q5 ( OR= 0.160, 95%CI: 0.031-0.827, P=0.029). (2) After adjusting for confounding factors, multivariate Logistic regression analysis showed that the probability of postoperative improvement of nerve function in patients from Q2 and Q3 was significantly higher than that in patients from Q5 ( OR=2.144, 95%CI: 1.043-4.407, P=0.038; OR=2.224, 95%CI: 1.105-4.479, P=0.025); the probability of postoperative improvement of nerve function in patients from G3 and G4 was significantly higher than that in patients from G5 ( OR= 2.153, 95%CI: 1.081-4.287, P=0.029; OR=2.182, 95%CI: 1.131-4.210, P=0.020). (3) After adjusting for confounding factors, multivariate Cox proportional risk model showed that the risk of primary endpoint event in patients from Q1 and Q2 was significantly lower than that in patients from Q5 ( HR=0.079, 95%CI: 0.010-0.613, P=0.015; HR=0.211, 95%CI: 0.062-0.724, P=0.013). (4) After adjusting for confounding factors, multivariate Cox proportional risk model showed that the risk of secondary endpoint events in patients from Q1, Q2, Q3 and Q4 was significantly lower than that in patients from Q5 ( HR=0.246, 95%CI: 0.100-0.607, P=0.002; HR=0.360, 95%CI: 0.177-0.732, P=0.005; HR=0.448, 95%CI: 0.246-0.817, P=0.009; HR=0.467, 95%CI: 0.252-0.867, P=0.016). Conclusion:The risks of postoperative intracranial hemorrhage, primary endpoint event and secondary endpoint events in patients with acute ischemic stroke decrease with the decrease of systolic blood pressure during peri-thrombolysis period; moderate blood pressures (systolic blood pressure: 130.00-147.99 mmHg; diastolic blood pressure:76.20-90.79 mmHg) are beneficial for improvement of neurological function.

Objective: To analyze the clinical features of perianal condyloma acuminatum in HIV infected men who have sex with men (MSM) and assess the effects of combined treatment of microwave and photodynamic therapy. Methods: Clinical and laboratory data of 260 male patients with perianal condyloma acuminatum were collected and microwave combined with photodynamic therapy was applied on them. Results: The majority of the patients with perianal condyloma acuminatum were young people (243/260). Warts were mainly located in the anus or from the outside to inside of the anus (245/260). Among them, the proportion of warts position of extraanal in HIV-infected group (8/220) was lower than that of non-HIV-infected group (7/40). HPV types 11 (70/118), 6 (44/118) and 16 (40/118) were the most common types of HPV infection. People with HIV infection were more likely to develop high-risk, mixed types HPV infection and multiple HPV infection than those without HIV infection. More than half of the patients (146/260) needed only 1-3 sessions of photodynamic treatments. There was no significant difference in the times of photodynamic treatments and the numbers of photosensitizers required between the HIV-infected and non-HIV-infected groups. The recurrence rate of HIV-infected group (13.6%, 30/220) was also similar to that of non-HIV-infected group (15.0%, 6/40), but far lower than those who underwent microwave therapy alone (45%, 18/40). Conclusions The combination therapy significantly reduced the recurrence rate of perianal condyloma acuminatum in HIV infected MSM.