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 evaluate the efficacy of different interventions to the extra cranial lesions in acute ischemic stroke(AIS)due to anterior tandem lesions(TL)on reperfusion.Methods As a multi-center,cross-sectional study,AIS due to anterior TL receiving mechanical thrombectomy(MT)were retrospectively collected.Interventions to the extra-cranial stenosis were recorded.Post-procedural reperfusion was assessed using the modified thrombolysis in cerebral infarction(mTICI)score.Complete revascularization was defined as mTICI 3 and good revascularization was defined as mTICI 2b/3.The relationship between different extra-cranial intervention regi-mens and rate of re-vascularization was compared.Results Totally 117 patients were included with 92.3% reaching good recanalization and 63.2% reaching complete re-canalization.There was no significant difference in good re-canalization rates among various extra-cranial intervention regimens.The rate of complete re-canalization was significantly higher in patients receiving endovascular therapy(P＜0.05)and there was significant difference among various endovascular treatment regimens(P＜0.01):acute balloon angioplasty only group presented the highest rate of complete re-canalization(100.0% ),followed by acute stenting only group(80% ),acute stenting+balloon angioplasty group(73.7% )and conservative treatment group(54.3% ).Conclusions Endovascular inter-vention to extra-cranial stenosis contributes to complete re-canalization in AIS due to anterior TL receiving MT,and acute balloon angioplasty seems to be quite effective than acute stenting.

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 explore the source and control of radon in high radon houses in geothermal fields; Methods Radon concentration in indoor and soil was measured by ATD detector in winter and summer; radionuclides in building materials were measured by gamma-ray spectrometry; radionuclides dose rates of building materials were measured by 6150 A D/ 6H X-γ ray detector; and radon reduction technology was applied to one of the houses;Results The average radon concentrations in 32 rooms were （106.4 ± 63.7） Bq/m³ (summer) and （421.3 ± 138.2） Bq/m³ (winter), and the concentrations in 12.5% (summer) and 96.9% (winter) of the rooms exceed 150 Bq/m³. The average radon concentration in soil around buildings was 12890 Bq/m³ (n = 24), which is 1.7 times of the typical soil radon concentration in Beijing (7600 Bq/m³). After soil decompression, the radon concentration in the house could be reduced to less than 100 Bq/m³. The radon reduction rates of active decompression and passive decompression were 94.6% and 71.4%, respectively. Conclusion The effect of soil decompression on reducing radon concentration in the bottom rooms is obvious. Attention should be paid to the radon in residential environment of geothermal field.

Objective:To obtain the distribution characteristics of radon levels in drinking water in cities of China and analysis their influencing factors.Methods:A total of 31 cities were selected and 406 tap water samples were collected in accordance with the sampling plan based on administrative division. Radon concentrations in the water samples were determined by using RAD7 H 2O measuring devices, and the closed loop liquid-gas balance method and grab method . The radon concentrations in the gas loop were measured by using semiconductor detector. After four measurement periods, radon concentrations in water were calculated. Results:The arithmetic mean of radon concentrations in drinking water from 31 cities was (4.92±9.44) Bq/L and the geometric mean (0.71±7.77) Bq/L, ranging from less than the lower detection limit (LLD) to 43.15 Bq/L. For 84.2% of drinking water samples, radon concentrations were less than US EPA recommended 11.1 Bq/L, all lower than the EU-recommended value of 100 Bq/L.Conclusions:The radon concentrations in drinking water are higher in northeastern, northwestern, southwestern, northern China than those in southern, central China and eastern China. The factors influencing radon concentrations in drinking water are closely related to geological structure and water source type. Compared with the global values, the radon concentrations in drinking water in our cities are low and safe in general in China.

Chemical constituents from the air dried parts of Cichorium glandulosum were studied. The chemical constituents of C. glandulosum were separated and purified by means of silica gel, Sephadex-LH 20, ODS column chromatography and semi-preparative high performance liquid chromatography. The structure was elucidated by physicochemical characteristics and spectral data. One new flavonoid glycoside was isolated from C. glandulosum, and identified as quercetin-3-O-［6″-O-(3-ethoxy-1, 3-dioxopropyl)］-β-D-glucopyranoside(1).

Notoginseng Radix et Rhizoma has the efficacy of dissolving stasis and hemostasis and reducing swelling and easing pain. Panax notoginseng saponins (PNS) is the main active component of Notoginseng Radix et Rhizoma, and the main components include ginsenoside Rb1, Rg1, Re, Rd and notoginsenoside R1. Injections with PNS as the medicinal material basis have become main TCM injections for the treatment of cerebral vascular diseases, with confirmed clinical efficacy. This article reviewed the research progress in pharmacological effects, clinical application and adverse reactions of PNS in treatment of cerebral vascular disease, with a purpose to provide references for further research and clinical application.

Objective To investigate the relationship between indoor radon concentration and air exchange rate for new residential building.Methods The indoor radon concentration and air exchange rate were measured in two new roughcast houses in Guangzhou and Hefei,respectively.The radon concentration was measured using radon instrument.The air exchange rate was measured by using tracer gas dilution method.Results The indoor radon concentrations measured in Guanzhou for two bedrooms in a 48-hour closed condition were 106 and 115 Bq/m3,the range of 17-181 and 6-224 Bq/m3.Air exchange rates were 0.16/h and 0.21/h.In Hefei,the twice measured values for one bedroom were 148 and 186 Bq/m3,the range of 8-224 and 14-290 Bq/m3,and air exchange rates were 0.14/h and 0.12/h.The indoor radon concentration exponentially decreased with the increase of air exchange rates.Conclusions Attention should be paid to the indoor radon pollution issue that may arise in new residential buildings of energy-saving design due to low air exchange rate.

Objective To investigate the levels and distribution of radon in dwellings in Shenzhen cities of China.Methods A total of 108 low-,multi-,middle-and high-rise buildings were selected.Indoor radon concentrations were measured by using solid track detector.Results The arithmetic mean of indoor radon concentrations in Shenzhen was 64 Bq/m3,and geometric mean was 58 Bq/m3,in range of 15 to 155 Bq/m3.The average indoor radon concentration in Bao'an district was 50 Bq/m3 with the lowest value,and that in Pingshan new district was 87 Bq/m3 with the highest value.There were 12 measuring points where indoor radon concentrations were higher than 100 Bq/m3 in Shenzhen,accounting for 11.1％ of the total number.Shapiro-Wilk test showed that the frequency distribution of indoor radon concentration in Shenzhen follows lognormal distribution (P ＞ 0.05).The indoor radon concentrations showed a downward trend from 1990 to 2015.The indoor radon concentration decreases with the elevated floors except 10th and above floors.Conclusions The indoor radon concentrations in Shenzhen increased by 35％,compared to the previous investigations.It is recommended that efforts continue to improve radioactive materials standards about building material and to enhance the natural ventilation in high-rise buildings in order to lower the radiation hazards from radon.

Objective To investigate the levels and distribution of radon concentrations in groundwater in some representative cities in China,and estimate the effective dose from inhaled radon released from domestic groundwater.Methods A total of 12 cities in 7 provinces (municipalities) were selected,including Beijing,Inner Mongolia,Ningxia,Shaanxi,Henan,Liaoning and Heilongjiang.In total,73 water samples from groundwater supply were taken.Radon concentrations in water samples were determined by using a continuous radon monitor with air-water exchanger.Results The average radon content in groundwater for drinking was 11.8 Bq/L in 12 cities in 7 provinces,ranging from 1.0 to 63.8 Bq/L.The radon concentrations in 37％ water samples exceeded 1 1.1 Bq/L,the safe limit recommended for drinking water by the United States Environmental Protection Agency (EPA).The radon contents in all of the water samples was lower than the reference level 100 Bq/L recommended by World Health Organization (WHO).The average annual effective dose arising from inhaled radon released from groundwater was 29 μSv (2.4 to 160 μSv).Conclusions Generally,the effective dose from inhaled radon released from groundwater is negligibly low.However,in some areas dominated by granite bedrock,the dose contribution from radon released from groundwater to residents should be routinely monitored.