Objective To compare the results of accumulation and continuation methods in indoor radon measurement. Methods The radon concentrations in 30 households in 7 provincial capital cities of China were simultaneously measured using both accumulation and continuation methods. Results The radon concentration measured by accumulation method in 30 households ranged from 21 to 323 Bq/m³, with a median M(P₂₅, P₇₅) of 70.5 (43.8, 111). The radon concentration measured by the continuation method ranged from 16.1 to 258 Bq/m³, with a median M(P₂₅, P₇₅) of 100 (51.3, 141). The average relative percent deviation between the two measurement methods was 41.8%. There were significant differences among the measurement results at 8, 16, and 24 h by the continuation method. Pairwise comparisons showed there were statistical diffferences between 8 h and 16 h, as well as between 8 h and 24h; however, no statistical significance was found (P < 0.05), between 16 h and 24 h. Conclusion The overall continuous measurement results of the 30 households were higher than those of cumulation method. The comparison between accumulation and continuation measurement results did not show a high level of correlation (r=0.49). The continuation method is significantly affected by environmental factors, and the length of the measurement period can affect the measurement results. The selection of indoor radon measurement methods should consider the purpose, sample size, and environmental conditions.

Objective:To investigate the indoor radon concentrations and to analyze their seasonal variations in urban and rural residential dwellings in Ningxia province.Methods:From March 2022 to March 2023, based on the administrative region division and population distribution in Ningxia, a total of 143 typical residential dwellings, including 82 urban houses and 61 rural houses, were selected to measure indoor radon concentration by CR-39 solid nuclear track detectors for 1 year in Ningxia, with detectors changed every 3 months.Results:The annual average indoor radon concentration in Ningxia was 88 Bq/m 3, range 39-226 Bq/m 3. The annual average indoor radon concentration was below 100 Bq/m 3 for 69.9% of the measured dwellings, and below 300 Bq/m 3 for all of surveyed dwellings. Indoor radon concentrations in rural areas were much higher than those in urban areas ( Z=5.85, P<0.05). Indoor radon concentration varied significantly with the seasons, higher in autumn and winter, but lower in spring and summer, in total ( χ2=63.97, P<0.05), urban ( χ2=24.74, P<0.05), and rural ( χ2=43.15, P<0.05). Conclusion:The annual average indoor radon concentrations in all the measured dwellings are below the reference level of 300 Bq/m 3 recommended by Indoor Air Quality Standard (GB/T 18883-2022) in China.

OBJECTIVE: We aimed to analyze the current indoor radon level and estimate the population risk of radon-induced lung cancer in urban areas of China. METHODS: Using the passive monitoring method, a new survey on indoor radon concentrations was conducted in 2,875 dwellings across 31 provincial capital cities in Chinese mainland from 2018 to 2023. The attributable risk of lung cancer induced by indoor radon exposure was estimated based on the risk assessment model. RESULTS: The arithmetic mean (AM) and geometric mean (GM) of indoor radon concentrations were 65 Bq/m³ and 55 Bq/m³, respectively, with 13.6% of measured dwellings exceeding 100 Bq/m³ and 0.6% exceeding 300 Bq/m³. The estimated number of lung cancer deaths induced by indoor radon exposure was 150,795, accounting for 20.30% (95% CI: 20.21%-20.49%) of the lung cancer death toll. CONCLUSION This study provided the most recent data on national indoor radon levels in urban areas and the attributable risk of lung cancer. These results served as an important foundation for further research on the disease burden of indoor radon exposure and radon mitigation efforts.
Radon/analysis* ; China/epidemiology* ; Air Pollution, Indoor/analysis* ; Lung Neoplasms/etiology* ; Humans ; Cities/epidemiology* ; Air Pollutants, Radioactive/adverse effects* ; Neoplasms, Radiation-Induced/etiology* ; Risk Assessment ; Radiation Monitoring

Objective To investigate the indoor radon concentration and its changing trend in northeastern China. Methods We measured indoor radon levels cumulatively for over three months by solid state nuclear track detection in a total of 261 houses in multi-story or high-rise buildings in Shenyang, Changchun, Harbin, Heihe, and Yichun in northeastern China. The measurement lasted one year in Changchun for seasonal changes. Results The average indoor radon concentration in the five cities was 88 Bq/m³, ranging from 12 to 558 Bq/m³. The indoor radon concentrations were ≤ 100 Bq/m³ in 75.1% of the houses, and ≤ 300 Bq/m³ in 97.7% of the houses. The indoor radon concentration increased with the age of buildings. The indoor radon concentration was highest in winter, and it was higher in summer than in autumn and spring. Conclusion The indoor radon concentration in northeastern China increased compared with the data of 1980s and 1990s. It is highest in the winter heating season, and higher in summer than in spring and autumn. Indoor radon exposure deserves attention.

Objective To primarily investigate the indoor radon concentrations in the urban and rural dwellings in Yinchuan, China, and to estimate the effective dose. Methods A total of 67 dwellings, which included 49 urban households and 18 rural households in Yinchuan, were selected to cumulatively measure the indoor radon concentrations for more than 3 months using solid state nuclear track detection. Results The arithmetic mean, geometric mean, median, and range of indoor radon concentrations in urban and rural areas in Yinchuan were 64 Bq/m³, 59 Bq/m³, 57 Bq/m³, and 25-172 Bq/m³, respectively. Surveillance sites with an indoor radon concentration higher than 100 Bq/m³ accounted for 7.5%. Indoor radon concentrations in rural areas were higher than those in urban areas. Indoor radon concentrations were highest in winter and lowest in summer. The effective dose of indoor radon exposure among residents in Yinchuan was 1.86 mSv/a. Conclusion The results of indoor radon concentrations measured in this investigation in Yinchuan are significantly higher than those measured in the 1990s. The annual effective dose is higher than the mean levels in the world and China.

Objective To investigate the suitable methods for reducing the concentration levels of residential radon and its daughters. Methods Three rooms were selected and treated by natural ventilation, air purifier, and sealing/shielding, respectively. The EQF3120 device was used to measure the concentrations of radon and its daughters, and the alpha nuclear trail detector was used to measure indoor radon concentration. The three methods were compared in terms of radon reduction effect. Results After natural ventilation for 2-10 hours, the average reduction rates of the concentrations of radon and attached and unattached radon daughters in the room were 87.7%, 89.8%, and 93.7%, respectively; in the room with air purifier, the concentrations of radon and attached and unattached radon daughters were reduced by 46.3%, 94.5%, and 45.3%, respectively; after sealing and shielding, the concentration of radon was reduced by 74.9% after 1 month and 59.2% after 1 year. Conclusion All three methods have a marked effectin reducing the concentrations of indoor radon and its daughters, and natural ventilation is the most economical and effective method for reducing radon.

【Objective】 To explore the safety of RhD-positive red blood cells (RBCs) immunization schedules in RhD-negative volunteers, so as to facilitate the development of domestic anti-D immunoglobulin. 【Methods】 From January 2018 to April 2020, 23 RhD negative volunteers with informed consent were enrolled and divided into initial immunization group and booster immunization group. The initial immunization included first immunization, second immunization and third immunization. Four groups, i. e. 3 cases of 20 mL, 8 of 30 mL, 6 of 40 mL, and 6 of 50 mL, were involved in initial immunization. After the initial immunization response, booster immunizations were performed every 3 months. According to the anti-D titer before each immunization, the booster immunization doses were set to 0.5, 1 and 2 mL. Whole blood samples of 5mL/ person (time) were collected 24 h and 1 week after each infusion, and the blood routine, liver, kidney and blood coagulation function and anti-D titer were detected. The differences of detection (index) values at 24 h and 1 week after the first immunization and booster immunization in each (dose) group were compared. 【Results】 No statistically significant differences were observed in hemolysis index values (all within the range of medical reference values) 24 h or 1 week after initial immunization among RhD positive RBCs of 20, 30, 40 and 50mL(P>0.05). The differences between the hemolysis index values and the basic values before the immune response (all within the range of medical reference values) after 0.5 or 1 mL booster immunizations were also not statistically different (P>0.05). However, the differences (μmol/L)between total bilirubin levels and the basic values before the immune response (1.55±1.87, 6.29±2.66) were significantly different after 2 mL booster immunization (P<0.05). 【Conclusion】 No risks affecting the safety of RhD negative volunteers was found in the immunization schedule proposed in this study.

Objective    To investigate the diagnostic value of tuberculosis T cell spot test (T-SPOT.TB) and erythrocyte sedimentation rate (ESR) test in the diagnosis of simple pulmonary nodules in Xinjiang. Methods    A retrospective analysis of 72 patients with asymptomatic simple pulmonary nodules in the Department of Thoracic Surgery, the First Affiliated Hospital of Xinjiang Medical University from October 2017 to July 2019 was performed. According to the pathological results, the patients were divided into a tuberculoma group [n=23, including 14 males and 9 females, aged 37-84 (56.91±12.73) years] and a lung cancer group [n=49, including 31 males and 18 females, aged 34-83 (61.71±10.15) years]. The predictive value of T-SPOT.TB and ESR results for the diagnosis of simple pulmonary nodules was evaluated. Results    The positive rate of T-SPOT.TB in the tuberculoma group (69.60%) was higher than that in the lung cancer group (42.90%) (χ2=5.324，P=0.021), with a sensitivity of 69.56% and specificity of 57.14%; the positive ESR was 47.80%in the tuberculoma group and 59.20% in the lung cancer group, and no statistical difference was found between the two groups (χ2=0.981, P=0.322), with a sensitivity of 47.82% and specificity of 40.81%; the area under receiver operating characteristic curve (AUC) was 0.618, the 95% confidence interval of AUC was (0.479, 0.758), and the Youden’s index was 0.267 with a sensitivity of 69.60% and specificity of 57.10%. Difference in the T-SPOT.TB and ESR test results was statistically significant (χ2=4.986, P=0.026), but the correlation between the tests was weak with a Pearson contingency coefficient of 0.199. ESR results in patients with different ages were statistically different (χ2=7.343, P=0.025), but the correlation between age and ESR results was weak with a Pearson contingency coefficient of 0.239; T-SPOT.TB results in patients with different ages were not statistically different (χ2=0.865, P=0.649), and the correlation between age and ESR results was weak with a Pearson contingency coefficient of 0.084. Conclusion    The diagnostic value of T-SPOT.TB and ESR tests is small in the diagnosis of simple pulmonary nodules.

Animals ; Biological Transport, Active/physiology* ; Centrioles/metabolism* ; Cilia/metabolism* ; Mice ; Mice, Mutant Strains ; N-Acetylglucosaminyltransferases/metabolism*

Objective:To compare the effect of the 2% chlorhexidinegluconate disinfectant and 0.5% iodophor disinfectant on the maintenance of central venous catheter (CVC) in patients with immunodeficiency.Methods:The patients were randomly divided into two groups. 2% chlorhexidinegluconate disinfectant was used in the experimental group, and 0.5% iodophor disinfectant was used in the control group. The CVC was sterilized once a week and continuously maintained for 3 weeks. According to the condition of catheter, the dressing was changed in time in case of any problem,and the reason and time for the catheter nursing care were recorded. The duration of changing the catheter dressing in different disinfectant, incidence rate of dressings looseness and incidence of catheter-related infections in two groups were analyzed.Results:The duration of skin drying and duration of caring in the experimental group were (0.62±0.10)min, (11.67±0.33) min, significantly shorter than the control group [(1.97±0.18) min, (14.48±0.33) min]( t values were 63.044, 57.296, P<0.01).In term of the adverse effects on CVC,there were no statistical differences between two groups ( P> 0.05). Conclusions:Both 2% chlorhexidinegluconate and 0.5% iodophor disinfectant have similar disinfection effect on CVC caring, but 2% chlorhexidinegluconate disinfection is more efficient and worthy of application in clinical settings.