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Radiography Image Classification Using Deep Convolutional Neural Networks
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作者 Ahmad Chowdhury Haiyi Zhang 《Journal of Computer and Communications》 2024年第6期199-209,共11页
Research has shown that chest radiography images of patients with different diseases, such as pneumonia, COVID-19, SARS, pneumothorax, etc., all exhibit some form of abnormality. Several deep learning techniques can b... Research has shown that chest radiography images of patients with different diseases, such as pneumonia, COVID-19, SARS, pneumothorax, etc., all exhibit some form of abnormality. Several deep learning techniques can be used to identify each of these anomalies in the chest x-ray images. Convolutional neural networks (CNNs) have shown great success in the fields of image recognition and image classification since there are numerous large-scale annotated image datasets available. The classification of medical images, particularly radiographic images, remains one of the biggest hurdles in medical diagnosis because of the restricted availability of annotated medical images. However, such difficulty can be solved by utilizing several deep learning strategies, including data augmentation and transfer learning. The aim was to build a model that would detect abnormalities in chest x-ray images with the highest probability. To do that, different models were built with different features. While making a CNN model, one of the main tasks is to tune the model by changing the hyperparameters and layers so that the model gives out good training and testing results. In our case, three different models were built, and finally, the last one gave out the best-predicted results. From that last model, we got 98% training accuracy, 84% validation, and 81% testing accuracy. The reason behind the final model giving out the best evaluation scores is that it was a well-fitted model. There was no overfitting or underfitting issues. Our aim with this project was to make a tool using the CNN model in R language, which will help detect abnormalities in radiography images. The tool will be able to detect diseases such as Pneumonia, Covid-19, Effusions, Infiltration, Pneumothorax, and others. Because of its high accuracy, this research chose to use supervised multi-class classification techniques as well as Convolutional Neural Networks (CNNs) to classify different chest x-ray images. CNNs are extremely efficient and successful at reducing the number of parameters while maintaining the quality of the primary model. CNNs are also trained to recognize the edges of various objects in any batch of images. CNNs automatically discover the relevant aspects in labeled data and learn the distinguishing features for each class by themselves. 展开更多
关键词 CNN radiography Image Classification R Keras Chest X-Ray Machine Learning
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Current interventional options for palliative care for patients with advanced-stage cholangiocarcinoma 被引量:2
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作者 Maryam Makki Malak Bentaleb +3 位作者 Mohammed Abdulrahman Amal Abdulla Suhool Salem Al Harthi Marcelo AF Ribeiro Jr 《World Journal of Clinical Oncology》 2024年第3期381-390,共10页
Primary biliary tract tumors are malignancies that originate in the liver,bile ducts,or gallbladder.These tumors often present with jaundice of unknown etiology,leading to delayed diagnosis and advanced disease.Curren... Primary biliary tract tumors are malignancies that originate in the liver,bile ducts,or gallbladder.These tumors often present with jaundice of unknown etiology,leading to delayed diagnosis and advanced disease.Currently,several palliative treatment options are available for primary biliary tract tumors.They include percutaneous transhepatic biliary drainage(PTBD),biliary stenting,and surgical interventions such as biliary diversion.Systemic therapy is also commonly used for the palliative treatment of primary biliary tract tumors.It involves the administration of chemotherapy drugs,such as gemcitabine and cisplatin,which have shown promising results in improving overall survival in patients with advanced biliary tract tumors.PTBD is another palliative treatment option for patients with unresectable or inoperable malignant biliary obstruction.Biliary stenting can also be used as a palliative treatment option to alleviate symptoms in patients with unresectable or inoperable malignant biliary obstruction.Surgical interventions,such as biliary diversion,have traditionally been used as palliative options for primary biliary tract tumors.However,biliary diversion only provides temporary relief and does not remove the tumor.Primary biliary tract tumors often present in advanced stages,making palliative treatment the primary option for improving the quality of life of patients. 展开更多
关键词 CHOLANGIOCARCINOMA Palliative care Endoscopic treatment Surgery COMPLICATIONS interventional radiology
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The Interventional Capacity of Community Health Volunteers for Screening and Linkages of Non-Communicable Diseases in Nyeri County, Kenya
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作者 Kenneth Mugambi Jackline Nyaberi Elizabeth Echoka 《Open Journal of Preventive Medicine》 2024年第4期61-78,共18页
Non-communicable diseases (NCDs) account for 63% of mortalities. Approximately 80% of these NCD-related deaths occur in LMICs. A quasi-experimental study utilizing a non-equivalent pre-and post-test was conducted from... Non-communicable diseases (NCDs) account for 63% of mortalities. Approximately 80% of these NCD-related deaths occur in LMICs. A quasi-experimental study utilizing a non-equivalent pre-and post-test was conducted from May 2022 to March 2023 with 370 study participants. Multistage cluster and random sampling were used to select ten community units, and therefore, 150 CHVs were chosen for the control unit, and 150 were used to form the interventional group. Data was collected from the KOBO app. Six (6) homogenous FGDs comprised ten members, and 10 KII were conducted across study sites. Quantitative data was analyzed using SPSS version 28.0, and qualitative data was audio-recorded, transcribed, and analyzed via N-Vivo 12. The study shows that 59.3% of respondents have minimal information, and 92.7% (n = 139) have no clear understanding of NCDs, with a pre-intervention capacity of 48.8%. Independent sample t-test showed a significant difference in capacity from a pre-intervention average of 48.75 (SD ± 5.7)%, which increased to 68.28 (SD ± 7.6)%, p < 0.001. A well-designed community interventional model plays a pivotal role in grassroots healthcare delivery but requires optimization for NCD management. 展开更多
关键词 INTERVENTION Community Health Volunteers Non-Communicable Disease SCREENING Linkages
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Lenvatinib,sintilimab combined interventional treatment vs bevacizumab,sintilimab combined interventional treatment for intermediate-advanced unresectable hepatocellular carcinoma
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作者 Ru-Yu Han Lei-Juan Gan +9 位作者 Meng-Ran Lang Shao-Hua Ren Dong-Ming Liu Guang-Tao Li Ya-Yue Liu Xin-Di Tian Kang-Wei Zhu Li-Yu Sun Lu Chen Tian-Qiang Song 《World Journal of Gastroenterology》 SCIE CAS 2024年第43期4620-4635,共16页
BACKGROUND Bevacizumab and sintilimab combined interventional treatment(BeSiIT)and L envatinib and sintilimab combined interventional treatment(LeSiIT)are two commonly used therapeutic regimens for intermediate-advanc... BACKGROUND Bevacizumab and sintilimab combined interventional treatment(BeSiIT)and L envatinib and sintilimab combined interventional treatment(LeSiIT)are two commonly used therapeutic regimens for intermediate-advanced hepatocellular carcinoma(HCC)in clinical practice.AIM To compare the clinical efficacy and safety of BeSiIT and LeSiIT for the treatment of intermediate and advanced HCC.METHODS Patients diagnosed with intermediate-advanced HCC and initially treated with BeSiIT or LeSiIT in the Tianjin Medical University Cancer Institute and Hospital between February 2020 and July 2021 were included.The primary endpoint was progression-free survival(PFS),and the secondary endpoints were overall survival(OS),objective response rate(ORR),disease control rate(DCR),conversion rate,and treatmentrelated adverse events.RESULTS Total 127 patients met the inclusion criteria and were divided into BeSiIT and LeSiIT groups.Twenty-eight and fifty patients in the BeSiIT and LeSiIT groups,respectively,were assessed after 1:2 propensity score matching.PFS and OS rates were not significantly different between the two groups.No significant variations were noted in ORRs or DCRs according to the Response Evaluation Criteria in Solid Tumors(RECIST),and modified RECIST.BeSiIT group showed a better conversion rate than the LeSiIT group(P=0.043).Both groups showed manageable toxicity profiles.Multivariate analysis showed that the independent factors associated with PFS were alphafetoprotein levels and carcinoembryonic antigen score.CONCLUSION In intermediate-to-advanced HCC,the BeSiIT and LeSiIT groups exhibited acceptable toxicities and comparable PFS,OS,and ORR. 展开更多
关键词 Hepatocellular carcinoma Molecular targeted therapy IMMUNOTHERAPY interventional treatment Propensity score matching
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In situ study on columnar-equiaxed transition and anaxial columnar dendrite growth of Al-15%Cu alloy by synchrotron radiography 被引量:3
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作者 李发国 东青 +5 位作者 张佼 戴永兵 付亚楠 谢红兰 尹付成 孙宝德 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第7期2112-2116,共5页
Directional solidification of Al-15% (mass fraction) Cu alloy was investigated by in situ and real time radiography which was performed by Shanghai synchrotron radiation facility (SSRF). The imaging results reveal... Directional solidification of Al-15% (mass fraction) Cu alloy was investigated by in situ and real time radiography which was performed by Shanghai synchrotron radiation facility (SSRF). The imaging results reveal that columnar to equiaxed transition (CET) is provoked by external thermal disturbance. The detaching and floating of fragments of dendrite arms are the prelude of the transition when the solute boundary layer in front of the solid-liquid interface is thin. And the dendrite triangular tip is the fracture sensitive zone. When the conditions are suitable, new dendrites can sprout and grow up. This kind of dendrite has no obvious stem and is named anaxial columnar dendrites. 展开更多
关键词 Al-15%Cu alloy directional solidification columnar to equiaxed transition synchrotron X-ray radiography
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Landscape of transarterial chemoembolization represented interventional therapy for hepatocellular carcinoma
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作者 Yang-Yang Fu Wen-Mao Li +1 位作者 Hong-Qiao Cai Yan Jiao 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第12期3903-3906,共4页
This article discusses the article written by Tan et al.Transarterial chemoembol-ization(TACE)is one of the main treatment methods for advanced hepatocellular carcinoma(HCC).There are other vascular interventional the... This article discusses the article written by Tan et al.Transarterial chemoembol-ization(TACE)is one of the main treatment methods for advanced hepatocellular carcinoma(HCC).There are other vascular interventional therapies,including drug-eluting bead TACE,transarterial radioembolization,and hepatic arterial infusion chemotherapy.TACE combined with anti-angiogenesis therapy may improve tumor control and prolong progression free survival.The combination therapy of TACE and immunotherapy may improve the clinical efficacy of HCC.In future research,more basic and clinical studies are needed to explore the immunogenic intervention therapy. 展开更多
关键词 Transarterial chemoembolization interventional therapy Hepatocellular carcinoma ANTI-ANGIOGENESIS IMMUNOTHERAPY Programmed cell death 1
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Analysis of The Impact of Interventional Nursing on The Therapeutic Effect, Negative Emotions, and Quality of Life of Patients Undergoing Cardiovascular and Cerebrovascular Interventional Therapy
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作者 Xiaohui Niu 《Journal of Clinical and Nursing Research》 2024年第4期44-49,共6页
Objective: To explore the impact of interventional nursing on the therapeutic effect, negative emotions, and quality of life of patients undergoing cardiovascular and cerebrovascular interventional therapy. Methods: A... Objective: To explore the impact of interventional nursing on the therapeutic effect, negative emotions, and quality of life of patients undergoing cardiovascular and cerebrovascular interventional therapy. Methods: A total of 106 patients who underwent cardiovascular and cerebrovascular interventional treatment were collected and randomly divided into Group A (control) and Group B (observation), with 53 cases each. Group A received the routine nursing intervention and Group B received the interventional nursing intervention. The clinical efficacy, complications, negative emotions, quality of life, and nursing satisfaction of the two groups of patients were evaluated. Results: The total clinical effective rate of Group B (52/98.12%) was higher than that of Group A (45/84.91%) (χ^(2)= 4.371, P < 0.05). The total incidence of complications in Group B (2/3.78%) was lower than that of Group A (9/16.98%) (χ^(2)= 4.970, P < 0.05). The self-rating anxiety (SAS) score and self-rating depression (SDS) of Group B were lower than those of Group A (P < 0.001). The quality of life of Group B was significantly higher than that of Group A (P < 0.001). The nursing satisfaction of group B (51/96.22%) was higher than that of group A (43/81.13%) (χ^(2)= 6.014, P < 0.05). Conclusion: In the care of patients undergoing cardiovascular and cerebrovascular interventional therapy, interventional nursing intervention effectively improved the patient’s clinical efficacy, reduced the incidence of complications, reduced negative emotions, improved the quality of life, and increased nursing satisfaction. 展开更多
关键词 interventional nursing Cardiovascular and cerebrovascular interventional treatment EFFICACY
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Analysis of the Significance of Key Points of Patient Interventional Psychological Care and Pain Care
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作者 Xiaoping Dai Chu Luo Jiawei Dai 《Journal of Clinical and Nursing Research》 2024年第3期66-71,共6页
Interventional therapy has become increasingly popular in clinical practice due to advancements in medical technology.However,patients often experience psychological and physiological pressure due to its invasive natu... Interventional therapy has become increasingly popular in clinical practice due to advancements in medical technology.However,patients often experience psychological and physiological pressure due to its invasive nature.The management of patient discomfort and tension is crucial to ensure effective treatment.Psychological and pain management are essential components of interventional therapy,as they significantly impact patient recovery and prognosis.This article discussed the importance of interventional psychological and pain care for patients,starting with the development and spread of interventional therapy.The significance of providing high-quality nursing services to patients and improving their quality of life was also discussed. 展开更多
关键词 interventional treatment Psychological nursing Pain care Key points Significance analysis
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The Effect of Predictive Nursing Intervention on Cardiac Function and Clinical Outcomes in CCU Patients with Acute Myocardial Infarction After Interventional Therapy
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作者 Tingting Wang Cui Xia 《Journal of Clinical and Nursing Research》 2024年第8期237-242,共6页
Objective:To evaluate the impact of predictive nursing on the care of acute myocardial infarction(AMI)patients in the Coronary Care Unit(CCU)after interventional therapy.Methods:From September 2021 to September 2023,8... Objective:To evaluate the impact of predictive nursing on the care of acute myocardial infarction(AMI)patients in the Coronary Care Unit(CCU)after interventional therapy.Methods:From September 2021 to September 2023,84 AMI patients admitted to the CCU were randomly divided into two groups:the experimental group(42 patients)received predictive nursing,and the reference group(42 patients)received conventional nursing.Cardiac function and clinical outcomes were compared between the groups.Results:Before nursing,there was no difference in cardiac function between the two groups(P>0.05).After nursing,the cardiac function of the experimental group was better than that of the reference group(P<0.05).The clinical outcomes of the experimental group were better than those of the reference group(P<0.05).Before nursing,there was no difference in psychological scores between the two groups(P>0.05).After nursing,the psychological scores of the experimental group were lower than those of the reference group(P<0.05).Conclusion:Predictive nursing can improve the cardiac function and clinical outcomes of AMI patients after interventional therapy and can also regulate patients’negative psychological states. 展开更多
关键词 Predictive nursing CCU Acute myocardial infarction interventional therapy Cardiac function
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The Impact of Patient Education on the Nursing Care of Perioperative Patients in the Interventional Catheterization Room
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作者 Cui Yang Huan Xiong +1 位作者 Mao Li Yuanyuan Liu 《Journal of Clinical and Nursing Research》 2024年第1期19-24,共6页
Objective:To explore and analyze the effect of implementing a precise education model on the nursing care of perioperative patients in the interventional catheterization room.Methods:We selected 70 patients who were g... Objective:To explore and analyze the effect of implementing a precise education model on the nursing care of perioperative patients in the interventional catheterization room.Methods:We selected 70 patients who were going to undergo surgical intervention in our hospital from August 2020 to December 2022 as the subjects for this study through random sampling.The patients were divided into a control group and an observation group,with 35 cases in each group.The control group underwent basic nursing intervention,and the observation group was given precise patient education.The nursing effects of both groups were observed.Results:After the intervention,all compliance indicators of the observation group were better than those of the control group(P<0.05).Besides,the incidence of complications in the observation group(2.86%)was lower than that of the control group(17.14%)with P<0.05.Furthermore,the patient satisfaction of the observation group(97.14%)was higher than that of the control group(82.86%),with P<0.05.Conclusion:A precise propaganda and education model facilitates the nursing of perioperative patients in the interventional catheterization room.Therefore,this practice should be popularized. 展开更多
关键词 Patient education model interventional catheterization room Perioperative period Nursing effect
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Development of Brief Image Quality Evaluation Criteria for Digital OrthoPantomography (OPG) Images in Dental Radiography
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作者 A.M.C. Kumarihami S.D.L. Heshani +1 位作者 P. Sathyathas R.P. Illeperuma 《Journal of Health Science》 2018年第3期139-147,共9页
An OPG (orthopantmography) is an extra-oral radiographic imaging method which provides a panoramic or wide view of both jaws and teeth on a single image. Digital OPG images provide high contrast with more details o... An OPG (orthopantmography) is an extra-oral radiographic imaging method which provides a panoramic or wide view of both jaws and teeth on a single image. Digital OPG images provide high contrast with more details of the dentitions. The research main objective was to produce sophisticated and effective criteria that can be used by any radiographer with sound knowledge to identify common errors of digital OPG images and to increase the concern of high frequency of errors to minimize them to give an optimum image quality. The study was designed as retrospective cross sectional study. Hundred digital OPG images are evaluated by three qualified radiographers who had dental radiography experience and four student radiographers. Paired t-test was used to see the difference between the responses of radiographers and student radiographers. Kruskal-Wallis Test was used to see difference between each evaluator. Possible errors of OPG were divided into four main categories (identification, artifact, anatomical coverage and patient positioning). Each main category consists of sub-categories. Values of subcategories were given according to their importance to get the total of 100% for each main category. The results showed that there is no significant difference between radiographers and student radiographers’ responses and also between each evaluator. Hence it shows that the criteria were an easy understandable and user-friendly tool. And results showed the frequent error category was loss of anatomical coverage and frequent error was absence of positioning the tongue against the palate. 展开更多
关键词 OPG radiography dental radiography evaluation criteria.
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Evaluation of an asymptomatic COVID-19 patient post-surgery with chest radiography: A surgeon’s dilemma
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作者 Gaurav Govil Lavindra Tomar Pawan Dhawan 《World Journal of Virology》 2021年第6期326-328,共3页
Routine chest radiography is not a requirement in post-surgery cardiac bypass patients.However,the safety of abandoning routine chest radiographs in critically ill patients remains uncertain.Surgery in an asymptomatic... Routine chest radiography is not a requirement in post-surgery cardiac bypass patients.However,the safety of abandoning routine chest radiographs in critically ill patients remains uncertain.Surgery in an asymptomatic coronavirus disease 2019(COVID-19)patient presents additional challenges in postoperative management.Chest radiography remains a valuable tool for assessment of all patients,even a stable one.Management of surgical patients as an emergency in an asymptomatic COVID-19 case remains a surgeon’s dilemma. 展开更多
关键词 COVID-19 Cardiac surgery radiography Critical care Chest radiography Intensive care POSTOPERATIVE
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Contrast sensitivity in 14 MeV fast neutron radiography 被引量:5
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作者 Chang-Bing Lu Jie Bao +4 位作者 Ying Huang Peng Xu Xiong-Jun Chen Qi-Wei Zhang Xi-Chao Ruan 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第6期115-122,共8页
Fast neutron radiography(FNR) is an effective non-destructive testing technique.Due to the scattering effect and low detection efficiency,the detection limit of FNR under certain conditions cannot be determined.In ord... Fast neutron radiography(FNR) is an effective non-destructive testing technique.Due to the scattering effect and low detection efficiency,the detection limit of FNR under certain conditions cannot be determined.In order to obtain the minimum detectable thickness by FNR,we studied the contrast sensitivity of FNR lead samples,both theoretically and experimentally.We then clarified the relationship between pixel value and irradiation time,and sample materials and thickness.Our experiment,using a4-cm-thick lead sample,verified our theoretical expression of FNR contrast sensitivity. 展开更多
关键词 FAST NEUTRON radiography CONTRAST sensitivity EXPERIMENTAL research
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Digital radiography of crush thoracic trauma in the Sichuan earthquake 被引量:2
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作者 Zhi-Hui Dong Heng Shao +5 位作者 Tian-Wu Chen Zhi-Gang Chu Wen Deng Si-Shi Tang Jing Chen Zhi-Gang Yang 《World Journal of Radiology》 CAS 2011年第11期273-278,共6页
AIM:To investigate the features of crush thoracic trauma in Sichuan earthquake victims using chest digital radiography(CDR).METHODS:We retrospectively reviewed 772 CDR of 417 females and 355 males who had suffered cru... AIM:To investigate the features of crush thoracic trauma in Sichuan earthquake victims using chest digital radiography(CDR).METHODS:We retrospectively reviewed 772 CDR of 417 females and 355 males who had suffered crush thoracic trauma in the Sichuan earthquake.Patient age ranged from 0.5 to 103 years.CDR was performed between May 12,2008 and June 7,2008.We looked for injury to the thoracic cage,pulmonary parenchyma and the pleura.obtained in 349 patients,the remaining 423 patients underwent only AP CDR.Thoracic cage fractures,pulmonary contusion and pleural injuries were noted in 331(42.9%;95% CI:39.4%-46.4%),67 and 135 patients,respectively.Of the 256 patients with rib fractures,the mean number of fractured ribs per patient was 3.Rib fractures were mostly distributed from the 3rd through to the 8th ribs and the vast majority involved posterior and lateral locations along the rib.Rib fractures had a significant positive association with non-rib thoracic fractures,pulmonary contusion and pleural injuries(P < 0.001).The number of rib fractures and pulmonary contusions were significant factors associated with patient death.CONCLUSION:Earthquake-related crush thoracic trauma has the potential for multiple fractures.The high number of fractured ribs and pulmonary contusions were significant factors which needed appropriate medical treatment. 展开更多
关键词 Earthquake PLEURA Pulmonary PARENCHYMA radiography THORACIC TRAUMA
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Comparison of conventional radiography and MDCT in suspected scaphoid fractures 被引量:4
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作者 Cyrus Behzadi Murat Karul +6 位作者 Frank Oliver Henes Azien Laqmani Philipp Catala-Lehnen Wolfgang Lehmann Hans-Dieter Nagel Gerhard Adam Marc Regier 《World Journal of Radiology》 CAS 2015年第1期22-27,共6页
AIM: To determine the diagnostic accuracy and radiation dose of conventional radiography and multidetector computed tomography(MDCT) in suspected scaphoid fractures.METHODS: One hundred twenty-four consecutive patient... AIM: To determine the diagnostic accuracy and radiation dose of conventional radiography and multidetector computed tomography(MDCT) in suspected scaphoid fractures.METHODS: One hundred twenty-four consecutive patients were enrolled in our study who had suffered from a wrist trauma and showed typical clinical symptoms suspicious of an acute scaphoid fracture. All patients had initially undergone conventional radiography. Subsequent MDCT was performed within 10 d because of persisting clinical symptoms. Using the MDCT data as the reference standard, a fourfold table was used to classify the test results. The effective dose and impaired energy were assessed in order to compare the radiation burden of the two techniques. The Wilcoxon test was performed to compare the two diagnostic modalities.RESULTS: Conventional radiography showed 34 acute fractures of the scaphoid in 124 patients(42.2%). Subsequent MDCT revealed a total of 42 scaphoid fractures. The sensitivity of conventional radiography for scaphoid fracture detection was 42.8% and its specificity was 80% resulting in an overall accuracy of 59.6%. Conventional radiography was significantly inferior to MDCT(P < 0.01) concerning scaphoidfracture detection. The mean effective dose of MDCT was 0.1 m Sv compared to 0.002 m Sv of conventional radiography.CONCLUSION: Conventional radiography is insufficient for accurate scaphoid fracture detection. Regarding the almost negligible effective dose, MDCT should serve as the first imaging modality in wrist trauma. 展开更多
关键词 MUSCULOSKELETAL imaging SCAPHOID fracture MULTIDETECTOR computed tomography Biplane radiography Emergency radiology Diagnostic accuracy WRIST trauma Dose calculation
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Resolution analysis of thermal neutron radiography based on accelerator-driven compact neutron source 被引量:7
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作者 Lian-Xin Zhang Si-Ze Chen +6 位作者 Zao-Di Zhang Tao-Sheng Li Chuan Peng Lei Ren Rui Zhang Dan Xiao Yong Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第5期139-151,共13页
Owing to the immobility of traditional reactors and spallation neutron sources,the demand for compact thermal neutron radiography(CTNR)based on accelerator neutron sources has rapidly increased in industrial applicati... Owing to the immobility of traditional reactors and spallation neutron sources,the demand for compact thermal neutron radiography(CTNR)based on accelerator neutron sources has rapidly increased in industrial applications.Recently,thermal neutron radiography experiments based on a D-T neutron generator performed by Hefei Institutes of Physical Science indicated a significant resolution deviation between the experimental results and the values calculated using the traditional resolution model.The experimental result was up to 23%lower than the calculated result,which hinders the achievement of the design goal of a compact neutron radiography system.A GEANT4 Monte Carlo code was developed to simulate the CTNR process,aiming to identify the key factors leading to resolution deviation.The effects of a low collimation ratio and high-energy neutrons were analyzed based on the neutron beam environment of the CTNR system.The results showed that the deviation was primarily caused by geometric distortion at low collimation ratios and radiation noise induced by highenergy neutrons.Additionally,the theoretical model was modified by considering the imaging position and radiation noise factors.The modified theoretical model was in good agreement with the experimental results,and the maximum deviation was reduced to 4.22%.This can be useful for the high-precision design of CTNR systems. 展开更多
关键词 Neutron radiography Spatial resolution Accelerator-driven neutron source GEANT4 MTF ESF
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Imaging internal density structure of the Laoheishan volcanic cone with cosmic ray muon radiography 被引量:4
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作者 Ya-Ping Cheng Ran Han +8 位作者 Zhi-Wei Li Jing-Tai Li Xin Mao Wen-Qiang Dou Xin-Zhuo Feng Xiao-Ping Ou-Yang Bin Liao Fang Liu Lei Huang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第7期115-124,共10页
Muon radiography is a promising technique for imaging the internal density structures of targets such as tunnels,pyramids,and volcanoes up to a scale of a few hundred meters by measuring the flux attenuation of cosmic... Muon radiography is a promising technique for imaging the internal density structures of targets such as tunnels,pyramids,and volcanoes up to a scale of a few hundred meters by measuring the flux attenuation of cosmic ray muons after they have traveled through these targets.In this study,we conducted experimental muon radiography of one of the volcanoes in the Wudalianchi area in Northeast China to image its internal density structure.The muon detector used in this study was composed of plastic scintillators and silicon photomultipliers.After approximately one and a half months of observing the crater and conduit of the Laoheishan volcano cone in Wudalianchi from September 23^(rd) to November 10^(th) 2019,more than 3 million muon tracks fulfilling the data selection criteria were collected.Based on the muon samples and high-resolution topography obtained through aerial photogrammetry using an unmanned aerial vehicle,a density image of the Laoheishan volcano cone was constructed.The results obtained in this experiment demonstrate the feasibility of using a radiography technique based on plastic scintillator detectors.To obtain the density distribution,we performed a detailed background analysis and found that low-energy charged particles dominated the background noise.Relatively higher densities were found near the surface of the volcanic cone,whereas relatively lower densities were found near the center of the volcanic cone.The experiment in this study is the first volcano muon tomography study performed in China.Our work provides an important reference for future research. 展开更多
关键词 Muon radiography Muon transmission imaging Density
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Monte Carlo simulation for bremsstrahlung and photoneutron yields in high-energy x-ray radiography 被引量:1
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作者 许海波 彭现科 陈朝斌 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第6期213-220,共8页
This paper reports on the results of calculations using a Monte Carlo code (MCNP5) to study the properties of photons, electrons and photoneutrons obtained in the converted target and their transportations in x-ray ... This paper reports on the results of calculations using a Monte Carlo code (MCNP5) to study the properties of photons, electrons and photoneutrons obtained in the converted target and their transportations in x-ray radiography. A comparison between measurements and calculations for bremsstrahlung and photoneutrons is presented. The radiographic rule and the effect of the collimator on the image are studied with the experimental model. The results provide exact parameters for the optimal design of radiographic layout and shielding systems. 展开更多
关键词 x-ray radiography BREMSSTRAHLUNG PHOTONEUTRON energy spectrum angular distribution
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Comparison of therapeutic effectiveness of combined interventional therapy for 1126 cases of primary liver cancer 被引量:9
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作者 Ya-Min Liu Hao Qin +2 位作者 Chong-Bao Wang Xiao-Hong Fang Qing-Yong Ma 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第31期5060-5063,共4页
AIM: To verify the effect of combined interventiona therapy for hepatocellular carcinoma (HCC). METHODS: The clinical data of 1126 HCC patients who received combined interventional therapy for transcatheter arteri... AIM: To verify the effect of combined interventiona therapy for hepatocellular carcinoma (HCC). METHODS: The clinical data of 1126 HCC patients who received combined interventional therapy for transcatheter arterial chemoembolization (TACE) before or after hepatectomy, TACE and radio-frequency ablation (RFA), Chinese medicine treatment and biotherapy after TACE or transcatheter arterial infusion (TAI), were reviewed according to the results of their liver function, alpha-fetoprotein, image data, color-ultrosonography finding and survival rate. RESULTS: A total of 874 patients were followed up for a period of 2 to 63 mo. The overall 1-, 3- and 5- year survival rates were 67.8%, 28.7% and 18.8% respectively. The 1- 3- and 5- year survival rates of patients who received TACE were 74.7%, 41.4%, 36.9% before hepatectomy and 78.9%, 40.4%, 37.5% after hepatectomy. The effective rate (PR + NC) after TACE and RFA was 93.4%, the 1- and 3- year survival rates were 74.5% and 36.8% after TACE and RFA. The effective rate of PR + NC after TACE was 83.2%. The 1-, 3- and 5- year survival rates were 69.3%, 21.7%, 8.4% after TACE. The effective rate of PR + NC after TAI was 27.5%, the 1- and 2- year survival rates were 11.6% and 0% after TAI. The liver function, color-ultrosonography finding and alpha-fetoprotein after TACE + RFA, TACE and TAI were compared. There was no significant difference in each index between TACE and RFA or TACE as well as in liver function between TACE and RFA or between TACE and TAI. CONCLUSION: The therapeutic effectiveness of TACE before or after hepatectomy is most significant, while the effect of TACE and RFA is better than that of TACE, and the effect of TAI is minimal. 展开更多
关键词 Hepatocellular carcinoma Transcatheter arterial chemoembolization Combined interventional therapy Survival analysis
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Areal density and spatial resolution of high energy electron radiography 被引量:4
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作者 Jiahao Xiao Zimin Zhang +13 位作者 Shuchun Cao Ping Yuan Xiaokang Shen Rui Cheng Quantang Zhao Yang Zong Ming Liu Xianming Zhou Zhongping Li Yongtao Zhao Chuanxiang Tang Wenhui Huang Yingchao Du Wei Gai 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第3期321-326,共6页
Ultrafast imaging tools are of great importance for determining the dynamic density distribution in high energy density(HED)matter.In this work,we designed a high energy electron radiography(HEER)system based on a lin... Ultrafast imaging tools are of great importance for determining the dynamic density distribution in high energy density(HED)matter.In this work,we designed a high energy electron radiography(HEER)system based on a linear electron accelerator to evaluate its capability for imaging HED matter.40 MeV electron beams were used to image an aluminum target to study the density resolution and spatial resolution of HEER.The results demonstrate a spatial resolution of tens of micrometers.The interaction of the beams with the target and the beam transport of the transmitted electrons are further simulated with EGS5 and PARMELA codes,with the results showing good agreement with the experimental resolution.Furthermore,the experiment can be improved by adding an aperture at the Fourier plane. 展开更多
关键词 high energy density matter high energy electron radiography areal density resolution spatial resolution
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