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  • 28 June 2018 Volume 27 Issue 3
      

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  • JIA Jingxuan, WU Rongjun, WANG Yiyuan, LI Wenzhi, NIE Lingxiao, XU Jingjing
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    Objective The calculation method of the fuel element cladding damage monitoring channel measurement value in PWR (Rressurized Water Rector) nuclear power plant under different operating conditions is established.The dose rate of the channel was calculated under the condition of three primary coolant concentrations. Guide the setting of alarm threshold for the monitoring channel.Methods This article analyzed the radioactive nuclides in the primary coolant under different operating conditions of PWR nuclear power plant.According to the actual design of the fuel element damage monitoring channel, the calculation model is established by MCAM modeling software. The model can be used for MCNP software calculation. The measured values of the fuel element damage monitoring channel are calculated in three different operating conditions.Results Under three operating conditions, the calculated value of the monitoring channel are 8.0×10-6Gy/h、5.3×10-4Gy/h、1.6×10-3Gy/h.Conclusion It is suggested that 5.3×10-4Gy/h and 1.6×10-3Gy/h are set to two alarm thresholds. The setting of the alarm threshold is equivalent to the operating threshold of the active power station.
  • YANG Yongxin, WANG Song
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    Objective The calculation of the penetrating radiation field is required around highly enriched plutonium for the purpose of the workers' radiation safety assessment and the nuclear safety review, in which the penetration mechanism and the strength of the neutron and γ from plutonium needs to be analyzed deeply.Methods The composition and the radiation characteristic of the highly enriched plutonium is analyzed deeply, then the method which is appropriate for the γ and neutron dose rate calculation of the highly enriched plutonium is put forward based on the attenuation law of γ broad-beam and the neutron removal cross section theory.Results The theoretical calculation value of the surface γ dose rate and the neutron flux close to the highly enriched plutonium material is the same order of magnitude as the measured value, and shows that the model is correct. The actual measured values of γ dose rate from 0cm,30cm,100cm from the surface of plutonium material are all larger than the calculated values, and the farther the distance is, the larger the relative error is. The relative error between the neutron simulation and the actual measurement decreases with the increase of distance.Conclusion Through principle analysis and experimental verification, the calculation models presented for the penetrating radiation dose is reasonably and can meet the requirement of scientific and veracity.
  • DUAN Weizhen, HE Liangguo, LI Linyu, HE Ling, ZHANG Yang
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    Objective To analyze the artificial and natural radionuclide contents in foodstuff surrounding the nuclear facilities in Sichuan Province, and evaluate their committed dose to public.Methods Samples including grain, vegetables, meat, milk powder and tea in 5 regions surrounding the nuclear facilities were collected, and the specific activities of 238U, 238Ra, 131I, 232Th, 137Cs, 134Cs, 100Agm, 58Co, 60Co, and 40K were analyzed by using high purity germanium (HPGe) gamma-ray spectrometry.Results Among the 197 samples, the detectable rates of 40K, 232Th, 226Ra, 238U and 137Cs were 100%, 50.8%, 38.5%, 15.2% and 13.2%, respectively. Even though 137Cs was detected out in 26 samples, its activity did not exceed the national standard. The activity in milk powder produced in Sichuan was higher than those of other provinces. The total committed effective dose to adults caused by radionuclides in foodstuff was estimated to be 0.22 mSv, and the effective dose of 137Cs was 7.81×10-6 mSv.Conclusion The radionuclide contents in foodstuff and their committed dose to public in Sichuan Province are close to other reported values at home or abroad.
  • GENG Jiwu, ZHANG Zaoqin, XU Zhiqiang, OU Chengshan, ZHOU Meijuan, ZHOU Cheng
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    Objective To study the change of the Nitric Oxide ("NO") in the animal livers after being exposed to a lethal dosage of γ-Ray and its correlations with the expression of p53.Methods The experimented animals were raised at room temperature and were fully and evenly exposed to one-time X-ray at a lethal dosage of 9.0 Gy separately. The change of the NO in two groups' animal livers were monitored with the NO testing kits respectively before exposure, one hour、three hours、six hours、nine hours、twelve hours and twenty four hours after exposure and the expressions of iNOS and p53 in the livers were detected with the immunohistochemical SABC method.Results After exposure of the lethal dosage, the NO concentration in the livers shows a changing curve, namely, it increases first, then decreases but tends to be normal later. The concentration begins to increase after six-hours exposure and stops increasing till twelve hours later with a statistical difference(P<0.05)in comparison with the normal level and it will decrease to normal range after twenty four hours'exposure. After a lethal dosage, the specimens of the animal livers demonstrate positive expressions of iNOS and P53 and their correlation coefficient is 0.797(P<0.01).Conclusion After the exposure of the lethal dosage, NO concentration in the livers show a changing rule of increasing early and decreasing then and is positively correlative with the expression of p53.
  • WANG Chang, LI Jinrong, MO Sufang, ZHANG Jingbo, TAN Hanyun, LI Xiaotong
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    Objective To understand and discuss the incidence and influencing factors of the lymphocyte micronucleus abnormality in the radiation workers in Guangzhou.Methods Using 1:1 matched case-control study. Case group:from January 1, 2014 to December 31, 2014, the lymphocyte micronucleus rate is greater than or equal to 6‰ in the 1050 radiation workers who took occupational health examinations in a center, with a total of 24 cases. Control group:24 cases of radiation workers who had been examined at the same center and were in the same work unit, gender, age difference ±5 years, and lymphocyte micronucleus rate were normal. According to the occupational health examination form for radiation workers to collect the general baseline, the ionizing radiation exposure, the contact of confounding factors and the physical examination project indicators of research object. And single factor and multifactor conditional logistic regression analysis was respectively used to analyze the influencing factors of the abnormal lymphocyte micronucleus rate.Results The incidence of the lymphocyte micronucleus abnormality of radiation workers in Guangzhou was 2.29﹪. Smoking or passive smoking was the only statistically significant variable (OR=3.667).Conclusion The abnormal condition of lymphocyte micronucleus of the radiation workers in Guangzhou is normal, Smoking or passive smoking is the possible risk factor for the exceeded lymphocyte micronucleus rate.
  • LU Weiwei, XUE Hongjun
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    Objective To acquaintance the personal external doses in medical system in Benxi during the previous five years, and to grasp the differences among different medical institutions.Methods Taking the results of the personal dose in our city's medical system during 2011 to 2015 as research objects, and statistically ananlyze the related data by retrospective method.Results From 2011 to 2015, the total number of radiation workers was 2093 person-year. The total collective dose was 698.06 mSv, and the annual average dose was 0.334 mSv/a. As for the annual average dose in different medical institutions, the descend order was county-level, enterprise, private, city-level and township.Conclusion In the medical system of our city, the level of occupational external exposure to radiation workers was under the national standard.
  • SUN Xiaona, LIU Feng, WU Liya
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    Objective To acquaintance and analyze the current response ability for nuclear and radiation health emergency in Xinjiang, and to provide the basis for improving the ability construction in municipal level.Methods By filling out the questionnaire in the information platform, information about the basic information of nuclear and radiation, organization, professional personnel, material and equipment, health emergency ability, training and drilling are collected. All of the investigators were trained before using the information platform.Results The emergency plans were developed in 90.48%, 50% and 46.67% of the north, east and south regions, respectively. In the northern, southern and eastern Xinjiang, the units of emergency equipment were 16.57, 11.20 and 3.50 per institute, with an average of 12.79. In the rescue teams, medical staff accounted for up to 60.87%, while the decontamination staff was only 9.57%. In the south, they lacked of staff with the skills of decontamination and dose estimation. As for the comprehensive ability, the levels in the north, south and east were 15.48%, 10% and 6.25%, respectively. In the consultation team, the medical experts accounted for 50.00%, while the decontamination experts were only 5.00%, and the rate of comprehensive skills ranged from 20.00% to 40.00% among the experts. From 2014 to 2016, six times of training and drilling were performed in the south or north of Xinjiang, 1098 people were trained and 132 people participated in the drilling.Conclusion The response ability for nuclear and radiation health emergency is still inadequate in most regions of Xinjiang, and it exists a regional difference. In the future, the health emergency response system and institution should be established for dealing with nuclear and radiological accidents in the 3 regions, and the corresponding facilities and equipment should be equipped. Among the health emergency response team, training and drilling should be enhanced for those under 45.
  • LIU Ran, MA Qiao, LIAO Xiangdong, HU Bo
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    Objective To verify the photon beam absorbed dose of multi-leaf collimators small fields on IMRT by using TLDs.Methods TLDs were placed on the central axis of a 2.0cm thick mold, and the mold was put in the 15 cm×15 cm×15 cm solid polystyrene phantom. The phantom was scanned by a CT, and its images were transmitted to the TPS to make the plan. The SSD was set to be 100 cm and field were set to be 2.0 cm×5.0 cm.In the plan, the TLDs set at the 10cm depth of the central axis were exposed with 2 Gy by using 6MV X-ray. After exposure, the results of TLDs were measured and compared with the planned values.Results The relative deviations between planned dose and measured dose for 10 accelerators were 0.8%, 0.4%, -19.8%, 1.0%, 1.9%, 3.3%, -10.6%, -0.8%, -1.8% and 1.0%, respectively.Conclusion Among the 10 accelerators, the deviations between the planned and measured dose for 2 accelerators were beyond the limit of ±5.0%.
  • YUAN Jilong, CHENG Jinsheng
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    Objective Comparative analysis of the quality control measurements of the offline EBT3 film analysis and the online real-time analysis radiation optical dosimetry system in proton and heavy ion accelerator's radiation field dose distribution.Methods For active spot scan protons and carbon ions, the spread-out Bragg peak (SOBP) is 3 cm, and the range is 7 cm, 16 cm, 29 cm, respectively, radiotherapy planning system plans 100 mm×100 mm radiation fields, Using EBT3 film and radiation optical dosimetry to measure the dose distribution of the radiation field under various conditions, the EBT3 are scanned after 24 hours' irradiation and the optical system's image are acquired by real time shooting. The comparative dosimetry index is the Full width at half maximum (FWHM).Results Through comparative analysis, regardless of physical significance or statistical analysis, both detectors could measure the dose distribution of proton and heavy ion radiation field, and the results have good consistency and accuracy.Conclusion Both detectors meet the measurement requirements for proton and heavy ion radiation field's dosimetry parameters, Radiation optical dosimetry is capable of on-line dose distribution of radiation field measurement in real time, and more suitable for the development of the quality control of radiation therapy.
  • GAO Xuan, LI Kexin, JU Yongjian, CAO Liyuan
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    Objective To Analyze the setup error and its effect on dose distribution in IMRT for prostate cancer patients.Methods 45 prostate cancer patients underwent CBCT as the first treatment and compared with the original treatment plan to get the value of bed shifting. Then the setup error were calculated though these values, and patients were divided into two groups, A (≤ 6mm) and B (> 6mm). Then the patients'differences of age, BMI, bladder and rectum volume changes in A and B were compared. Also after bed shifting, the dose parameters of target and OARS were recalculated and compared with that calculated from original treatment plan.Results 1. The bed shifting values in X, Y and Z directions of 45 patients are 0.020 ±0.407 cm, -0.031 ±0.424 cm and -0.107±0.273 cm individually. 2. The difference of BMI between A (23 patients) and B (22 patients) has statistically significant, but the difference of age, bladder and rectum volume changes have no statistically significance. 3. Compared the dose parameters between original plan and latter plan after shifting the treatment bed, the differences of PTV95, the average dose of PTV, CTV95, average dose of CTV and the bladder V60 all have statistically significance, But the differences of rectum V60 and femoral head V20 have no significant difference.Conclusion In prostate cancer patients IMRT,the setup error must be care about, it may be related to the patient's BMI, but has limited/no relationships with the ageand bladder rectal volume changes in this study, and it must be corrected by shifting treatment bed, otherwise it will cause the dose distribution error in the target area and OARs.
  • SHI Jianhua, SHI Jianzhong
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    Objective To understand medical X-ray diagnostic equipment image quality control status of the medical institutions in Shanxi Province.Methods According to the relevant national standards, the multi-functional quality detector with X-ray machine and performance testing tools were used to test the quality control of the medical X-ray diagnostic equipment in some medical institutions in Shanxi Province.Results All single qualified rates in medical X-ray radiography equipment test items were 100%, except 94.4% of linearity of output, 98.6% of deviation from exposure time indication, 95.8% of deviation from the verticality of useful beams, 77.5%, 85.9% of deviation from four sides and from center between light field and exposure field All single qualified rates in the fluoroscopy equipment test items were 100%, in addition to the 96.7%of the typical value of air kerma rate on the incident surface. Medical X-ray diagnostic equipment qualified rate in different groups under the jurisdiction of the level of difference was statistically significant in overall(P<0.05); comparison between the two groups:the provincial administrative group and the municipal administrative group, the municipal administrative group and the county administrative group,there was no significant difference in equipment qualification rates (P>0.0125). But there was significant difference between the provincial administrative group and the county administrative group (P<0.0125). In addition, there was no significant difference in qualification rate between the import group and the domestic group (P>0.05).Conclusion Regular medical X-ray image quality control testing is necessary.
  • KOU Qinghe, XIE Huaijiang, TONG Yushe, MA Li
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    Objective To acquaint the basic status of quality control of X-ray diagnostic equipment in a military region so as to improve radiation protection level.Methods According to the related national criterions, quality control tests for medical X-ray diagnostic equipment were carried out in the medical institutions in a military region.Results The qualified rates of radiography and fluoroscopy equipment were 84.7%,92.4% respectively. The total qualified rate was 88.7%. There was no statistical difference among different levels of medical institutions.Conclusion There existed some problems in quality control of X-ray diagnostic equipment in the military region. It is necessary to strengthen the quality control tests of X-ray diagnostic equipment, especially for the low level institutions.
  • HU Bo, LIAO Xiangdong, LI Changhong, LIU Ran, MA Qiao
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    Objective To understand the performance status of SPECT and improve the quality control of the SPECT by testing 9 SPECT equipments in Sichuan province.Methods According to the relevant national and NEMA standards, using SPECT performance detection mode and image analysis code, the performance of the 9 SPECTs were measured including their tomographic spatial resolution, system planar sensitivity, system spatial resolution, intrinsic counting rate performance, intrinsic spatial resolution, intrinsic spatial resolution, intrinsic uniformity, intrinsic spatial differential linear.Results In the 7 performance indicators, the intrinsic uniformity and the intrinsic spatial differential linear qualification rate are relatively low, the pass rate is only 44.4% and 33.3%, intrinsic counting rate performance and the intrinsic spatial resolution pass rate are 88.9%, and the other indexes pass rate are 100%.Conclusion Users should have some daily maintenance skills and awareness, take quality control measures for equipment, emphasize the importance of performance testing for SPECT devices, so as to improve the quality of clinical diagnosis.
  • XIAO Hong, GUO Changyi, GAO Linfeng, YAO Jie, WANG Bin, QIAN Aijun
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    Objective To acquaintance the using status of radiation protective appliance in diagnostic X-ray examinations among adults in Shanghai, and provide guidance for further efforts of medical radiation protection for the public.Methods A total of 2933 examinees from 18 tertiary hospitals, 36 secondary hospitals and 56 first-class hospitals in Shanghai were selected by the convenient sampling method, and they were asked to complete the questionnaire survey in the help of the investigators. The chi square test and logistic regression analysis were used for statistical analysis.Results The utilization rate of radiation protective appliance in diagnostic X-ray examinations among the adults in Shanghai was 52.7%. The main type of protective appliance was the lead apron (45.5%) and lead collar (30.3%). The utilization rate in secondary hospitals (62.5%) was higher than that in tertiary hospitals (54.4%) or primary hospitals (35.9%), and the differences were statistically significant (P<0.05), while there was no significant difference in the utilization rate of protective appliance between the X-CT scans and the conventional X-ray examinations (P>0.05).Conclusion The utilization rate of radiation protective appliance in diagnostic X-ray image examinations among adults in Shanghai still has a large room for improvement. The radiation protection propaganda and education in the community and hospitals should be strengthened to improve the self consciousness of the patients, and to promote the initiative of radiation workers to implement radiation health protection requirements of the examinees.
  • CHENG Xiyuan, LIAO Yanpeng, LIU Shupeng, WANG Chuang, YANG Shaozhou, KANG Lili
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    Objective To summarize and analyze radiation protection management of certain medical institutions through evaluation of control effect on X-ray diagnostic radiology and interventional therapy in 38 medical institutions.Methods The evaluation of control effects was based on information research,field investigation, performance testing and radiological health protection testing.Results The coincidence level of accident emergency response, law, regulation and standards for personnel arrangement, protective measures examination, radiation protection monitoring respectively reach 94.7%, 68.4% and 71.1%. The passing rate for the first-time performance testing of DSA、DR、CT and Dental X-ray devices respectively reach 100%,82.6%,92.6% and 100%; and the rate for machine room radiological protection and monitoring testing of the above reach 100%,100%,92.6% and 100%.In terms of the performance testing, DR test standard has added new specific test items as Dark Noise, DDI, STP. However, some factory products have yet to open the certain functions because it is hard to take the preprocessed image to do testing; the area of higher monitoring value for machine room radiological protection occurred in the inspection window, the door include the edge and cable trench through the wall.Conclusion The current medical institution's awareness of control the radiological hazard has been raised up. Compared with the former testing and evaluation, the medical institutions obviously improve the device performance and the coincidence degree of protection test results. The device annual inspection, quality control and other management needed to be enhanced.
  • GUO Luzhen, CHEN Ling, LUO Zhiping, LIU Yang
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    Objective Develop a continuous and real-time radon monitor, which is used to measure radon concentration in the air for online monitoring and warning.Methods The detector based on ion collection principle, ANSYS CFX software and Ansoft Maxwell software is used to simulate and optimize the flow field and electric field distribution of parallel plate ionization chamber to improve the detector performance. A high sensitivity electrometer is used to reflect the real-time changes of ionization current collected by ion chamber for showing the changes of radon concentration.Results After testing, the detector has a fast response time to the changes of radon concentration and the sensitivity of radon measurement is 0.23 fA/Bq·m-3.Conclusion The detector can be applied to measure the real-time radon concentration of high radon sites such as uranium mine roadway and basement for reminding relevant personnel to take protective measures.
  • YUE Xihong, LIU Biao, WANG Yuwen
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    Objective Analysis of the level of natural radioactivity in Xinjiang coal and potential occupational exposure to uranium associated coal mine.Methods Base on the reported data on the natural radioactivity in Xinjiang coal in recent years, the level of natural radioactivity in Xinjiang coal was analyzed and compared.Results Through analysis, it was found that the concentration of 238U in Xinjiang coal was similar to the levels of the world average, the United States and Russia, and the concentration of 232Th was lower than those of the world average, the United States and Russia. Furthermore, the concentrations of 238U and 232Th were lower than the average concentrations in China, and they are within the range of normal natural background.Conclusion From the view point of radiological hygiene, rational exploitation and utilization of coal resources in Xinjiang will not affect the health of miners and residents.
  • DING Hongshen, XIA Bing, GE Ting
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    Objective To establish a suitable method for collecting tritiated water vapor in air in low-temperature environment (-15℃~5℃), and to provide technical support for monitoring tritiated water vapor in the ambient air surrounding nuclear power plants in the north.Methods Taking 3A molecular sieve as the adsorbent, and using the pump to sample the tritiated water vapor in the ambient air. The performances of sampling rate, efficiency, memory effect were tested and optimized for the better applicability.Results At a flow rate from 1.0 L/min to 3.0 L/min, the sampling efficiency was larger than 99%, and the memory effect was about 3%.Conclusion The method is applicable for collecting tritiated water vapor in low temperature environment in winte.
  • XU Mingfa, ZHANG Hongwei, XIANG Huiyun, PENG Wenbin, SHI Weili, LIN Chen
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    Objective To acquaintance the distribution of sealed radioactive sources used in sugar factories in Guangxi and evaluate the radiation effects on the surrounding environment, occupational staff, and the public. To provide scientific basis for the use and management of the sealed radioactive source in sugar factories.Methods According to the monitoring specifications, the gamma dose rate meter was used to measure the radiation environment of all sugar factories using sealed radioactive sources in Guangxi. The impacts were estimated based on the monitoring results, and combined with the monitoring individual doses.Results The gamma dose rates around the sites using sealed radioactive sources were higher than the environmental background level, and occupational workers and members of the public would receive a certain radiation dose.Conclusion The annual effective doses of ccupational staff and members of the public meet the relevant requirements.
  • WANG Haihua, QIAN Qian, WANG Qiang, YANG Yong, ZHU Bo, YANG Luting
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    Objective Through testing and evaluation of the radiation protection status of a newly constructed PET-CT center in a hospital to ensure the health rights of radiation workers, examinees and the public, and to provide technical basis for the administrative approval.Methods The layout, shielding protection and safety control measures were analyzed, verified and tested on site, and the evaluation was based on the corresponding national laws, regulations and standards.Results The layout of the PET-CT center was reasonable, the equipment performance met the test requirements, and radiation protection measures for the workplace were adequate.Conclusion All of radiation protection measures in this project meet the requirements of relevant standards, and the health rights of staff, examinees and public could be effectively protected.
  • WANG Xiaomei, WANG Chi, ZHANG Fang, WU Hongtao, SHAN Yongle
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    Objective To investigate the occupational mental health status of offshore and onshore oil drilling workers in oil fields and to compare them, and to provide basis for the further development of mental health education.Methods 702 offshore and onshore oil drilling workers were investigatedby the Symptom Check List-90(SCL-90) and Occupational Stress Inventory Revised Edition(OSI-R).Results The scores of SCL-90 and 9 factors of offshore and onshore oil drilling workers were higher than that of the Chinese norm and oil male workers norm, and the difference was statistically significant (P<0.05).But there was no statistically significant difference between the two groups workers(P>0.05).The mental health status of offshore workers in 31~40 age were the worst, the married people were worse than unmarried, and the difference was statistically significant (P<0.05), while the latter differences of different age, marital status, had no statistical significance (P>0.05).The scores of Occupational Roles Questionnaire and Personal Strain Questionnaire of OSI-R of the former were lower than the latter, the recreation score was higher than the latter, and the difference was statistically significant (P<0.05).The former with 26~40 age and married had a high degree of occupational stress, which was statistically significant difference (P<0.05), while the latter differences of different age, marital status, each group had no statistical significance (P>0.05).Conclusion The occupational mental health of offshore and onshore oil drilling workers was poor, but there was little difference between them. While focusing on the focus of offshore oil drilling workers, the importance of onshore drilling workers should be increased.
  • WANG Xin, CHEN Yingmin, WANG Lei, YANG Shuhui, BI Mingwei, XU Jiaang
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    Objective To analyze the levels of radon concentrations in some mines in Shandong Province from 2015 to 2017 and to preliminarily evaluate the dose levels of occupational exposure.Methods The activity concentrations of radon were determined according to the methods of "Scintillation flask method for measuring radon concentration in the air" (GB/T 16147-1995). The occupational exposure was evaluated according to "Standard for controlling radon and its progenies in underground space"(GBZ 116-2002) and "Basic Standards for Protection Against Ionizing Radiation and for the Safety of Radiation Sources" (GB18871-2002).Results Among the inspection samples collected from 2015 to 2017, the average concentrations of 222Rn in 1002, 36 and 7 samples from coal mines, gold mines and iron ores were 21 Bq·m-3, 65 Bq·m-3 and 21 Bq·m-3, and the ranges were 14~377 Bq·m-3, 20~228 Bq·m-3 and 25~40 Bq·m-3 respectively.Conclusions 222Rn concentrations in the samples are lower than the action level set for underground constructions in "Standard for controlling radon and its progenies in underground space"(GBZ 116-2002), and the results of annual radiation exposure to the underground miners also conform to the occupational limits of "Basic Standards for Protection Against Ionizing Radiation and for the Safety of Radiation Sources" (GB18871-2002).
  • WANG Weibo, KONG Qi, LU Tingting, REN Jiazhong, YANG Guoren
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    Objective To investigate the correlation between the extent of peripancreatic and retroperitoneal effusion and clinical severity in patients with acute pancreatitis.Methods Sixty-seven(32 males,35 females,mean age 48 years) patients with acute pancreatitis were collected from June 2016 to June 2017. CT scan and enhanced imaging were performed about one week after its onset. The extent of peripancreatic and retroperitoneal effusion were observed. The relationship combine with the clinical severity of acute pancreatitis was analyzed. Spearman correlation analysis was used for statistical analysis.Results The extent of peripancreatic and retroperitoneal effusion is positively correlated with clinical severity(r=0.903, P<0.01).Conclusion The more severe of AP, the more extent of peripancreatic and retroperitoneal effusion.
  • WANG Xinran
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    Objective To investigate the correlation between the recurrence of hepatocellular carcinoma (HCC) microvascular invasion in MSCT and the recurrence of HCC.Methods A total of 2 years of follow-up were performed in the patients with radical resection of solitary liver cancer in our hospital. The recurrence point was followed up. The preoperative MSCT data were retrospectively analyzed. The MSCT tumor microvascular invasion and follow-up results were compared.Results There was a significant correlation between the signs of microvascular invasion of MSCT liver cancer, microvascular invasion and recurrence of liver cancer(P<0.05). The sensitivity, specificity and accuracy of MSCT in predicting the recurrence of hepatocellular carcinoma after operation were 71.88%(23/32), 81.48%(22/27) and 76.27%(45/59), respectively.Conclusion The signs of microvascular invasion of MSCT liver cancer have some correlation with the recurrence of liver cancer after operation.
  • XU Huihui, FENG Changming, HUO Yingjie, HE yanan, LI peixiu
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    Objective To investigate the correlation between apparent diffusion coefficient (ADC)value of MR diffusion weighted imaging (DWI)and grading in colorectal adenocarcinoma.Methods The data of 36 patients with colorectal neoplasms confirmed by pathology were retrospectively analyzed. MRI、DWI and enhanced examination were performed preoperatively. ADC values were calculated in each group to analyze the correlation with the grading colorectal adenocarcinoma by pearson correlation analysis.Results The mean ADC value were(0.734±0.070)×10-3 mm2/s in the poorly differentiated group(2 cases), (0.966±0.157)×10-3 mm2/s in the moderately differentiated group (10 cases).ADC value and grading colorectal adenocarcinoma were strong correlated (r=0.692,P=0.000). The three groups of high and low score ADC values were not statistically significant, The difference between the moderately differentiated group and the well-differentiated group (P=0.000) was statistically significant.Conclusion The ADC values of colorectal tubular carcinomas with different degrees of differentiation decrease with the degree of differentiation of the tumors. The two are correlated and provide a strong basis for evaluating the differentiation of colorectal tubular adenocarcinoma preoperatively. DWI and ADC measurement can evaluate the grade of malignancy and prognosis of colorectal tumor to some extent.