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Muscle mass correlates with rocuronium distribution volume and guides dose optimization in obese colorectal cancer patients
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作者 Zhan-Wen Li Zhe Liu Sheng-Qun Liu 《World Journal of Gastrointestinal Oncology》 2026年第1期176-189,共14页
BACKGROUND Perioperative anesthesia management of obese patients presents significant challenges as traditional total body weight-based dosing fails to achieve optimal anesthetic effects due to altered pharmacokinetic... BACKGROUND Perioperative anesthesia management of obese patients presents significant challenges as traditional total body weight-based dosing fails to achieve optimal anesthetic effects due to altered pharmacokinetic characteristics including abnormal drug distribution and clearance.Rocuronium exhibits markedly different distribution patterns in obese patients,with conventional weight correction methods inadequately addressing individual muscle mass variations that critically influence drug distribution.AIM To investigate the quantitative relationship between skeletal muscle index(SMI)and rocuronium distribution volume in obese colorectal cancer patients,establish a population pharmacokinetic model,and develop individualized dosing strategies based on muscle mass.METHODS A retrospective cohort study was conducted,including 100 obese patients(body mass index≥30 kg/m^(2))who underwent elective radical colorectal cancer surgery at our hospital from June 2023 to January 2025.Skeletal muscle mass was measured using InBody 260 body composition analyzer and SMI was calculated to assess muscle mass,with male SMI<7.0 kg/m^(2) and female SMI<5.7 kg/m^(2)as diagnostic criteria for sarcopenia.Plasma rocuronium concentrations were detected by liquid chromatography-tandem mass spectrometry/mass spectrometry,and nonlinear mixed-effect modeling was used to establish population pharmacokinetic modeling.Stepwise regression was used to screen covariates,and dosing regimens were optimized through Monte Carlo simulation.The primary endpoint was targeted plasma concentration achievement rate,and the secondary endpoint was postoperative residual muscle relaxation incidence.RESULTS Among 100 patients,35(35.0%)had sarcopenia and 65(65.0%)did not.Patients in the sarcopenia group were older(64.1±9.8 years vs 54.2±10.9 years,P<0.001)and had significantly lower SMI(6.2±0.8 kg/m^(2)vs 8.4±1.2 kg/m^(2),P<0.001).SMI showed strong positive correlation with rocuronium steady-state distribution volume(r=0.718,P<0.001)and moderate negative correlation with clearance(r=-0.502,P<0.001).A two-compartment population pharmacokinetic model was successfully established,with SMI being the most important covariate affecting central compartment distribution volume(△OFV=-41.2,P<0.001).Model validation showed bootstrap successful convergence rate of 92.3%,and 92.1%of observed values fell within prediction intervals in predicted concentration versus predicted concentration.The SMI-based individualized dosing regimen improved target exposure achievement rate from 82.0%in traditional regimen to 93.5%(P=0.009),and reduced postoperative residual muscle relaxation incidence from 13.0%to 3.5%(P=0.018).The sarcopenia group showed the most significant improvement in achievement rate,from 71.4%to 93.8%(P=0.017).CONCLUSION SMI shows strong correlation with rocuronium distribution volume in obese colorectal cancer patients and is a key factor affecting drug distribution.SMI-based individualized dosing strategies can significantly improve target exposure achievement rate and reduce postoperative residual muscle relaxation incidence,providing scientific evidence for precision anesthesia management in obese patients. 展开更多
关键词 Obesity ROCURONIUM Skeletal muscle index Population pharmacokinetics Individualized dosing Colorectal cancer SARCOPENIA
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Evaluation of polycarbonate films as detection materials for high‑dose electron beam radiation detection
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作者 Ke Wang Xiao‑Dong Wang Xiong‑Hui Fei 《Nuclear Science and Techniques》 2026年第1期141-151,共11页
In this study,the dosimetric characteristics(thickness applicability,preheating time,temperature and humidity dependence,in-batch uniformity,readout reproducibility,dose linearity,self-decay,and electron energy respon... In this study,the dosimetric characteristics(thickness applicability,preheating time,temperature and humidity dependence,in-batch uniformity,readout reproducibility,dose linearity,self-decay,and electron energy response)of engineered polycarbonate films irradiated with an electron beam(0–600 kGy)were investigated using photoluminescence spectroscopy.The results show a linear relationship between photoluminescence intensity and radiation dose when the thickness of the polycarbonate film is 0.3 mm.A higher fluorescence intensity can be obtained by preheating at 60℃ for 180 min before photoluminescence spectrum analysis.As the temperature during spectral testing and the ambient humidity(during and after irradiation)increased,the photoluminescence intensity of the polycarbonate films decreased.The photoluminescence intensity deviation of the polycarbonate films produced within the same batch at 100 kGy is 2.73%.After ten times of repeated excitations and readouts,the coefficients of variation in photoluminescence intensity are less than 8.6%,and the linear correlation coefficient between photoluminescence intensity and irradiation dose is 0.965 in the dose capture range of 20–600 kGy.Within 60 days of irradiation,the photoluminescence intensity of the polycarbonate film decreased to 60%of the initial value.The response of the 0.3 mm polycarbonate films to electron beams with energies exceeding 3.5 MeV does not differ significantly.This comprehensive analysis indicates the potential of polycarbonate films as a high-radiation dose detection material. 展开更多
关键词 Electron beam irradiation POLYCARBONATE dose detection Radiophotoluminescence Dosimetric characteristics
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双定位像联合Care Dose 4D技术在PET/CT体部检查中的临床价值
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作者 樊俊甫 黄伟 +3 位作者 杨田硕 朱荣华 魏静 陶维静 《医学研究与战创伤救治》 北大核心 2025年第11期1170-1175,共6页
目的研究双定位像联合Care Dose 4D技术在PET/CT体部扫描中的临床应用价值。方法收集2022年7月5日-2023年9月23日在南京医科大学附属淮安第一医院行Care Dose 4D模式下单定位像法(前后位)和双定位像法(前后位和侧位)2次PET/CT扫描的120... 目的研究双定位像联合Care Dose 4D技术在PET/CT体部扫描中的临床应用价值。方法收集2022年7月5日-2023年9月23日在南京医科大学附属淮安第一医院行Care Dose 4D模式下单定位像法(前后位)和双定位像法(前后位和侧位)2次PET/CT扫描的120例患者。计算患者体重指数(BMI)。设Care Dose 4D模式下单定位像法扫描为单定位像组,Care Dose 4D模式下双定位像法扫描为双定位像组。根据BMI值将患者再分为四个亚组:过低组(BMI<18.5 kg/m^(2))、正常组(18.5 kg/m^(2)≤BMI<25 kg/m^(2))、超重组(25 kg/m^(2)≤BMI<30 kg/m^(2))和肥胖组(BMI≥30 kg/m^(2))。记录患者2种扫描模式下毫安秒(mAs)、CT容积剂量指数(CTDI_(vol))、剂量长度乘积(DLP)并计算有效剂量(ED)。通过图像信噪比(SNR)、对比信噪比(CNR)客观评价图像质量;另外由2名高年资核医学诊断医师采用双盲法主观评价图像质量。采用配对样本t检验比较单定位像组及双定位像组的CTDI_(vol)、DLP、ED值。计算每个患者2次扫描辐射剂量差值,记为ΔCTDI_(vol)、ΔDLP及ΔED;分析不同BMI亚组(过低组、正常组、超重组及肥胖组)ΔCTDI_(vol)、ΔDLP及ΔED有无统计学差异。结果图像质量方面,客观评价除舌骨层面外,双定位像组图像SNR、CNR较单定位像组下降,其中左肾门层面及髂总动脉分叉层面差异具有统计学意义(P<0.05);医师主观评价两组图像质量均能满足临床诊断需求。辐射剂量方面,双定位像组[CTDI_(vol):(8.14±1.64)mGy、DLP:(704.89±146.91)mGy·cm、ED:(12.69±2.64)mSv]较单定位像组[CTDI_(vol):(9.49±2.05)mGy、DLP:(822.24±180.31)mGy·cm、ED:(14.80±3.25)mSv]明显下降,差异具有统计学意义(P<0.01)。随BMI升高患者辐射剂量下降越明显,其中正常组与超重组、正常组与肥胖组间ΔCTDI_(vol)、ΔDLP及ΔED差异均具有统计学意义(P<0.05)。结论双定位像联合Care Dose 4D技术应用于PET/CT体部扫描,在保证图像质量前提下,可有效降低患者CT辐射剂量。 展开更多
关键词 Care dose 4D技术 定位像 辐射剂量 图像质量 PET/CT
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Ultra-low dose computed tomography chest vs chest radiography in paediatric primary ciliary dyskinesia:A prospective study
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作者 Michael G Waldron Patrick W O'Regan +13 位作者 Michael Lane Sahil S Shet Eid Kakish Fiachra Moloney Niamh Moore Mary Jane Murphy Louise Beagan Barry J Plant David Mullane Muireann Ni Chroinin David J Ryan Kevin O'Regan Stephen P Power Michael M Maher 《World Journal of Radiology》 2025年第8期64-73,共10页
BACKGROUND Primary ciliary dyskinesia(PCD)is a rare condition characterised by dysmotile,immotile,or absent cilia.As a result of the impairment in respiratory mucociliary clearance,patients with PCD typically develop ... BACKGROUND Primary ciliary dyskinesia(PCD)is a rare condition characterised by dysmotile,immotile,or absent cilia.As a result of the impairment in respiratory mucociliary clearance,patients with PCD typically develop neonatal respiratory distress,nasal congestion,otitis media and recurrent respiratory infections leading to bronchiectasis and structural lung changes.These changes have been shown by chest computed tomography(CT)to develop in infancy and early childhood.Recent development and refinement of radiation-reducing CT techniques have allowed significant radiation dose reductions,with chest CT doses now in the range of chest radiography(CR).AIM To evaluate the efficacy of ultra-low dose CT(ULDCT)chest in identifying pulmonary changes within a PCD paediatric patient cohort.METHODS Paediatric patients with PCD who presented for routine clinical outpatient follow-up within the study period,were eligible for inclusion in the study.ULDCT and CR were performed on these patients and the results compared.Comparison metrics included radiation dose,subjective and objective image quality and disease severity.RESULTS Six paediatric patients(mean age 9 years)underwent clinically indicated ULDCT chest examinations and CR for surveillance of their PCD.The mean effective dose was 0.08±0.02 mSv,a dose that approximates that of a frontal and lateral chest radiograph.The average Brody II score across the entire cohort was 12.92,with excellent interrater reliability and intra-class correlation coefficient(ICC)of 0.98.The average Chrispin-Norman score on CR was 1 with excellent inter-rater reliability and ICC of 0.92.CONCLUSION ULDCT demonstrates superior diagnostic capabilities,minimal radiation dose penalty,and high interobserver reliability in comparison to CR.Thus,we advocate for ULDCT to be the preferred modality for surveillance imaging in paediatric PCD. 展开更多
关键词 Primary ciliary dyskinesia Ultra-low dose computed tomography Chest radiography Radiation dose Image quality
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CARE Dose 4D联合CARE kV技术在胸部CT扫描中的辐射剂量降低研究
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作者 张佩聪 《影像技术》 2025年第1期62-67,共6页
目的:探究在胸部CT扫描过程中启用CARE Dose 4D联合CARE kV技术对降低CT辐射剂量的有效性。方法:回顾性分析2023年1月至12月期间在本院进行胸部CT扫描的100例患者影像资料,根据是否应用CARE Dose 4D联合CARE kV技术将患者分为A组(常规胸... 目的:探究在胸部CT扫描过程中启用CARE Dose 4D联合CARE kV技术对降低CT辐射剂量的有效性。方法:回顾性分析2023年1月至12月期间在本院进行胸部CT扫描的100例患者影像资料,根据是否应用CARE Dose 4D联合CARE kV技术将患者分为A组(常规胸部CT扫描,n=50例)和B组(应用CARE Dose 4D联合CARE kV技术,n=50例)。采用德国西门子SOMATOM Force双源CT,详细设置包括自动毫安秒调节、120KV管电压等参数。比较两组的辐射剂量指标(CTDI(剂量指数)、DLP(剂量长度乘积)、ED(有效剂量))、图像质量客观评价(平均CT值、噪声(SD)、信号噪声比(SNR))和主观评分。结果:B组的辐射剂量指标显著低于A组(P<0.05);而两组的图像质量对比上无显著差异(P>0.05)。结论:胸部CT扫描中应用CARE Dose 4D联合CARE kV技术能显著减少辐射剂量,同时保持高质量的CT图像,为临床检查提供了一种安全有效的方法,为辐射防护最优化原则的实施提供了有力支持,具有广阔的临床应用前景。 展开更多
关键词 CARE dose4D联合CARE kV技术 胸部CT扫描 辐射剂量 图像质量
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Exploring the critical therapeutic window:Dose-frequency optimization of human umbilical cord mesenchymal stem cells for preclinical asthma treatment
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作者 Qiong-Hua Chen Jing-Yang Zheng +5 位作者 Yu-Qin Zhu Jun-Yao Zhang Chun-Yan Lin Xue-E Zhuang Jing Cheng Xiao-Yi Huang 《World Journal of Stem Cells》 2025年第9期190-199,共10页
BACKGROUND Current drugs primarily target inflammation control but do not reverse tissue remodeling changes for asthma.Human mesenchymal stem cells are known for their anti-inflammatory and tissue remodeling capabilit... BACKGROUND Current drugs primarily target inflammation control but do not reverse tissue remodeling changes for asthma.Human mesenchymal stem cells are known for their anti-inflammatory and tissue remodeling capabilities.However,limited research has explored the therapeutic impact of varying doses and frequencies of human umbilical cord blood-derived mesenchymal stem cells(HUC-MSCs)on established airway remodeling in experimental asthma.AIM To explore and optimize the dosage and administration frequency of HUC-MSCs in experimental models of ovalbumin(OVA)-induced asthma.METHODS BALB/c mice underwent sensitization and were challenged using OVA.Control animals were administered a saline solution following the same protocol.HUC-MSCs were identified using flow cytometry.HUC-MSCs at incremental dosages(1×105,2×105,4×105)were injected via tail veins on day 30(the second after the final stimulation).After comparing each group and determining the optimal dose,supplement the optimal dose twice on day 30 and day 33(the second and fifth day after the final stimulation).Bronchoalveolar lavage fluid(BALF)and serum were harvested for analysis of concentrations of interleukin-4(IL-4),IL-13,immunoglobulin E and interferon-gamma(IFN-γ)by enzyme-linked immunosorbent assay.Pharmacology of airways and lung functions were also evaluated to identify the optimal group.RESULTS The study shows that HUC-MSC transplantation ameliorates OVA-induced asthma by significantly reducing airway inflammation and obstruction in preclinical models.This effect is associated with decreased Th2 cytokines IL-4 and IL-13,and increased Th1 cytokine IFN-γ.The optimal dose of 2×105 cells/mouse was identified as the most effective in reducing local asthmatic airway inflammation and changing levels of IL-4,IL-13,and IFN-γin serum and BALF compared to other single doses of HUC-MSC.Multiple treatments with the medium dose(2×105 cells)of HUC-MSCs on days 30 and 33 yield the best pathological and lung function outcomes.However,double treatments do not reduce IL-4 and IL-13 expression or enhance IFN-γproduction in serum or BALF more effectively than a single medium dose.CONCLUSION HUC-MSCs effectively regulate pro-inflammatory mediators in serum and BALF,modulating airway remodeling and lung function.In this acute mouse asthma model,a single dosage of 2×105 is optimal,with more significant effects of decreasing airway obstruction requiring repeated administration. 展开更多
关键词 ASTHMA Human umbilical cord mesenchymal stem cells MOUSE dose FREQUENCY
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Radiotherapy dosage:A neural network approach for uninvolved liver dose in stereotactic body radiation therapy for liver cancer
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作者 Arunkumar Krishnan 《World Journal of Gastrointestinal Oncology》 2025年第2期315-317,共3页
A recent study by Zhang et al developed a neural network-based predictive model for estimating doses to the uninvolved liver during stereotactic body radiation therapy(SBRT)in liver cancer.The study reported a signifi... A recent study by Zhang et al developed a neural network-based predictive model for estimating doses to the uninvolved liver during stereotactic body radiation therapy(SBRT)in liver cancer.The study reported a significant advancement in personalized radiotherapy by improving accuracy and reducing treatment-related toxicity.The model demonstrated strong predictive performance with R-values above 0.8,indicating its potential to improve treatment consistency.However,concerns arise from the small sample size and exclusion criteria,which may limit generalizability.Future studies should incorporate larger,more diverse patient cohorts,explore potential confounding factors such as tumor characteristics and delivery technique variability,and address the long-term effects of SBRT. 展开更多
关键词 Liver cancer Radiotherapy dosage dose prediction Machine learning Stereotactic body radiotherapy
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Evaluation of Rivaroxaban at Different Doses on Symptoms,Blood Indicators,and Safety in Patients with Pulmonary Embolism during the Maintenance Phas 5 e
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作者 Xing Cheng 《Science International Innovative Medicine》 2025年第3期5-11,共7页
Objective:To investigate the differential effects of different rivaroxaban dosing regimens on symptom relief,fluctuations in laboratory parameters,and medication safety in patients with stable pulmonary embolism(PE).M... Objective:To investigate the differential effects of different rivaroxaban dosing regimens on symptom relief,fluctuations in laboratory parameters,and medication safety in patients with stable pulmonary embolism(PE).Methods:This study enrolled 100 patients in the maintenance phase of PE who were treated at our hospital between January 2022 and December 2023.They were randomly divided into a control group and an observation group using a random number table,with 50 subjects in each group.The treatment period was uniformly set at 6 months.The control group received oral rivaroxaban 10 mg once daily,while the observation group received oral rivaroxaban 5 mg once daily.The study focused on comparing the two groups regarding the degree of clinical symptom relief,coagulation function parameters(including D-dimer levels,PT,and APTT),cardiac function markers(NT-proBNP),and drug-related adverse events.All data were processed using SPSS 26.0 statistical software.Measurement data are presented as mean±standard deviation,intergroup differences were verified by t-test,categorical variables were analyzed by chi-square test,and the statistical significance level was set at P<0.05.Results:After six months of treatment intervention,there was no significant difference in the overall relief of core clinical symptoms such as dyspnea and chest pain between the two groups.Regarding laboratory indicators,post-treatment D-dimer levels,prothrombin time,activated partial thromboplastin time,and NT-proBNP values were significantly optimized compared to baseline in both groups(P<0.05),but intergroup comparisons did not reach statistical significance.Notably,the overall incidence of bleeding events in the observation group was significantly lower than that in the control group(P<0.05),while there were no significant differences in the incidence rates of other adverse events between the two groups.Conclusion:In the maintenance phase treatment of pulmonary embolism,rivaroxaban 5 mg and 10 mg doses are equivalent in efficacy regarding improvement of clinical symptoms and blood indicators.However,the 5 mg dose significantly reduces the risk of bleeding,offers better safety,and is more suitable for long-term anticoagulation management in some high-risk populations. 展开更多
关键词 RIVAROXABAN Different doses Pulmonary Embolism Maintenance Phase Treatment Clinical Symptoms Blood Indicators SAFETY Anticoagulation Therapy
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In vivo 3D dose distribution verification for lung cancer:from rigid-body model to porcine lung
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作者 Yutao Zhang Kai Xie +9 位作者 Lintao Song Jiewei Lai Haiping Zheng Qianjia Huang Hao Wang Tao Lin Liugang Gao Jiawei Sun Jianrong Dai Xinye Ni 《Bio-Design and Manufacturing》 2025年第6期994-1008,I0032,共16页
This study introduces a novel concept,biological in vivo three-dimensional(3D)dose distribution verification,aimed at investigating how respiratory motion affects the efficacy of lung cancer radiotherapy,representing ... This study introduces a novel concept,biological in vivo three-dimensional(3D)dose distribution verification,aimed at investigating how respiratory motion affects the efficacy of lung cancer radiotherapy,representing an evolution from the current standard of rigid-body dose distribution verification.A 3D ex vivo biological lung motion simulation device(3D-BioLungEx)was designed to replicate human respiration.A radiotherapy plan of the patient was copied to the porcine lung,which was driven by 3D-BioLungEx to simulate various respiratory patterns that occur during treatment.To ensure anatomical consistency with the patient’s lung structure,during transmission,skin,skeleton,and organs were adjusted according to CT images of the porcine lung.The patient’s radiotherapy plan was then adapted to the porcine lung using the Monaco treatment planning system(TPS).Next,an iterative optimization and scatter inversion-based dose distribution retro-analysis algorithm(IOSI-BLDose)was developed to calculate the dose distribution during treatment.Gamma passing rates were used to quantify discrepancies between this dose distribution and that of the radiotherapy plan.When respiratory conditions were replicated,the passing rate reached up to 93.61%,while irregular breathing dropped it to 70%-90%,primarily due to amplitude changes.However,cycle variations had minimal impact.Compared to conventional rigid-body dose distribution verification,our method provides real-time biological feedback and more effectively captures motion-induced deviations.Accordingly,our biological in vivo 3D dose distribution verification has potential for improving treatment precision and enabling adaptive radiotherapy in clinical practice. 展开更多
关键词 Biological lung 3D printing Motion simulation device RADIOTHERAPY Lung cancer dose distribution verification
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Saturation effect study and ion recombination correction on ionization chamber for ultra‑high dose rate (FLASH) of carbon ions
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作者 Xin-Le Lang Zheng-Guo Hu +10 位作者 Zhi-Guo Xu Juan Li Kai Zhou Fa-Ming Luo Yu-Cong Chen Rui-Shi Mao Chuan Huang Zu-Long Zhao Jia-Li Fu Li-Bin Zhou Guo-Qing Xiao 《Nuclear Science and Techniques》 2025年第10期35-46,共12页
The ionization chamber produces significant space-charge and ion recombination effects at ultra-high dose rates,posing achallenge for dose monitoring.In addition,there is no generally accepted ion correction model for... The ionization chamber produces significant space-charge and ion recombination effects at ultra-high dose rates,posing achallenge for dose monitoring.In addition,there is no generally accepted ion correction model for dosimetry in FLASHradiotherapy,making it crucial to monitor the dose at ultra-high dose rates accurately and in real time.In this study,the airpressure of the ionization chamber was reduced to perform real-time beam monitoring,and a Faraday cup was used for calibrationfor active dosimetry.To study the saturation effect of the ionization chamber,the drift,attachment,recombination,anddiffusion processes of the electron-ion pairs were modeled using finite-element analysis based on physical phenomenologicalprinciples,and the correction factor was calculated.The experimental results showed that the FLASH ionization chambermeasures good dose linearity at a dose rate of approximately 0.2 Gy/s.When the air pressure of the chamber was adjustedto 10 mbar,the response of the FLASH ionization chamber was linear at a dose rate of approximately 50 Gy/s,with theresiduals within 2%.Furthermore,by using physical phenomenology to resolve the process of electron-ion pair motion inthe sensitive volume of the ionization chamber,the analytical model better describes the saturation effect of carbon ions atultra-high dose rates.The maximum deviation in the calculated correction factor is less than 10%.We studied the saturationeffect in dose measurement,achieving accurate and fast dose and profile position measurement across different dose ratesin a wide range based on the Heavy Ion Research Facility in Lanzhou. 展开更多
关键词 FLASH radiotherapy Ultra-high dose rate Carbon ions·Dosimetry Saturation effect Correction factor
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Methodology for estimating external radiation dose exposed to deposited activated tungsten dust in the soil
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作者 Feng-Die Wang Bao-Jie Nie +2 位作者 Yu-Xuan Wang De-Yi Chen De-Zhong Wang 《Nuclear Science and Techniques》 2025年第9期226-235,共10页
Tungsten is considered the most promising plasma-facing material for fusion reactors with exceptional performance.Under certain conditions,activated tungsten dust can be generated through plasma–wall interactions and... Tungsten is considered the most promising plasma-facing material for fusion reactors with exceptional performance.Under certain conditions,activated tungsten dust can be generated through plasma–wall interactions and released into the atmosphere.Activated tungsten migrates downward in the soil after atmospheric deposition.However,effective methods for evaluating the environmental dose of gamma rays emitted by activated tungsten are still lacking.Consequently,a method for evaluating the air-absorbed dose rate of activated tungsten dust was proposed considering soil attenuation.Key parameters including the mass attenuation coefficient and energy absorption build-up factor were determined for the main gamma ray energies of radionuclides within the activated tungsten dust.Additionally,air-absorbed dose rates were calculated by assuming that radioactive sources were located at different soil depths and radii.It was found that a soil depth of 50 cm significantly attenuated the environmental dose by 99.9%,whereas the air-absorbed dose rates within the horizontal distance of 500 cm accounted for 91%of the total dose rate.Therefore,this study underscored the importance of soil attenuation in environmental dose assessments,which must be carefully re-examined for the safety analysis of fusion reactors. 展开更多
关键词 Fusion reactor Activated tungsten dust Soil attenuation Air-absorbed dose rates Monte Carlo method
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Clinical translation of ultra-high dose rate flash radiotherapy:Opportunities,challenges,and prospects
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作者 Xiang-Xiang Yang Hui Luo +2 位作者 Jia-Jun Zhang Heng Ge Liang Ge 《World Journal of Radiology》 2025年第4期1-11,共11页
Ultra-high dose rate flash radiotherapy(FLASH-RT)has attracted wide attention in the field of radiotherapy in recent years.For FLASH-RT,radiation is delivered at a very high dose rate[usually thousands of times compar... Ultra-high dose rate flash radiotherapy(FLASH-RT)has attracted wide attention in the field of radiotherapy in recent years.For FLASH-RT,radiation is delivered at a very high dose rate[usually thousands of times compared with conventional radiotherapy(CONV-RT)]in an extremely short time.This novel irradiation technique shows a protective effect on normal tissues,also known as the flash effect.At the same time,FLASH-RT is comparable to CONV-RT in terms of tumorkilling efficacy.As basic research dedicates to uncover the mechanisms by which FLASH-RT reduces radiation-induced normal tissue damage,clinical trials of FLASH-RT have been gradually conducted worldwide.This article systematically reviews the evidence of the feasibility and safety of FLASH-RT in clinical practice and offers insights into the future translation of this technology in clinic. 展开更多
关键词 Ultra-high dose rate flash radiotherapy MECHANISM Clinical translation Radiation-induced damage to normal tissues PROSPECTS
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In situ measurement of environmental γ radiation dose rates of key nuclides for large radioactive surface sources
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作者 Ze-Qian Wu Jian Sun +7 位作者 Wei-Qi Huang Bai-Rong Wang Jin-Xing Cheng Jiang-Feng Wu Yong-Hong Wang Biao Yuan Sheng Qi Kun Shan 《Nuclear Science and Techniques》 2025年第1期69-79,共11页
To monitor nuclear and radiation emergencies,it is crucial to obtain accurate in situ measurements of the environmentalγ radiation dose rate from key radionuclides,particularly for large radioactive surface sources.T... To monitor nuclear and radiation emergencies,it is crucial to obtain accurate in situ measurements of the environmentalγ radiation dose rate from key radionuclides,particularly for large radioactive surface sources.The methods currently used for measuring dose rates are inadequate for obtaining the dose rates of key radionuclides and have large angular response errors when monitoring surface sources.To address this practical problem,this study proposes three methods for measuring the dose rate:the weighted peak total ratio,mean value regression,and numerical integration methods.These methods are based on energy-spectrum measurement data,and they were theoretically derived and numerically evaluated.Finally,a 1-m-long hexagonal radioactive surface source was integrated into a larger surface source.In situ measurement experiments were conducted on a large radioactive surface source using a dose-rate meter and a portable HPGespectrometer to analyze the errors of the three aforementioned methods and verify their validity. 展开更多
关键词 Environmentalγradiation dose rate HPGespectrometer Key radionuclides Radioactive surface source
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The effectiveness of two doses of Hecolin vaccine in response to outbreaks in resource-limited settings
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作者 Fan Zhang Jianbo Xia Ling Wang 《Virologica Sinica》 2025年第6期1058-1060,共3页
Hepatitis E virus(HEV)represents a significant global cause of acute viral hepatitis.Annually,it is estimated to cause approximately 20.1 million infections worldwide,3.3 million of which result in symptomatic illness... Hepatitis E virus(HEV)represents a significant global cause of acute viral hepatitis.Annually,it is estimated to cause approximately 20.1 million infections worldwide,3.3 million of which result in symptomatic illness.In developing regions,genotypes HEV-1 and HEV-2 are the primary strains responsible for widespread outbreaks and epidemics of acute jaundice(icteric hepatitis),transmitted predominantly through the fecal-oral route via contaminated water and food(Devarbhavi et al.,2023). 展开更多
关键词 hecolin hepatitis e virus hev represents doses hepatitis E virus HEV VACCINE resource limited settings acute jaundice icteric
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Commentary on the dose-response effect of pre-exercise carbohydrates in McArdle disease:Methodological considerations and practical implications
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作者 Jiawei Du Jinghua Hou 《Journal of Sport and Health Science》 2025年第2期77-78,共2页
We read with great interest the recent article by Valenzuela et al.1titled“Dose-response effect of pre-exercise carbohydrates under muscle glycogen unavailability:Insights from McArdle disease”published in the Journ... We read with great interest the recent article by Valenzuela et al.1titled“Dose-response effect of pre-exercise carbohydrates under muscle glycogen unavailability:Insights from McArdle disease”published in the Journal of Sport and Health Science The study's exploration of the effects of varying carbohydrate(CHO)doses on exercise capacity in Mc Ardle disease,a condition characterized by complete muscle glycogen unavailability,is a significant contribution to the field of sports science and metabolic disorders. 展开更多
关键词 dose response exercise capacity mcardle disease published muscle glycogen sports science metabolic disorders McArdle disease pre exercise carbohydrates
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Enhanced inhibition of triple-negative breast cancer metastases with high-dose Rujifang treatment assessed by optical flow cytometry in vivo
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作者 Fuli Zhang Hongliang Li +9 位作者 Xianxun Zhong Xi Zhu Xuezhang Chen Bin Wang Zhixia Zhu Xikang Chen Guiwen Liang Jingtao Zhang Xunbin Wei Huaqin Tian 《Journal of Innovative Optical Health Sciences》 2025年第5期89-98,共10页
Triple-negative bresst canær(TNBC)metastscis is particularly severe due to its aggressive nsture,leading to rapid disease progresion and significantly reduced survival rates.Rujifang(RJF),a traditional Chinese fo... Triple-negative bresst canær(TNBC)metastscis is particularly severe due to its aggressive nsture,leading to rapid disease progresion and significantly reduced survival rates.Rujifang(RJF),a traditional Chinese formula,has demonstrated potential anti-tumor effects and theability to inhibit TNBC metastasis.However,the efects af varying R.IF dors remain undear.This study utilized Laser-based in vino fow cytometry(IVFC)to monitor circulating tumor cells(CTCs)and evaluate the efficacy of R.IF at different doses.The results indicated that R.IF at the high dose inhibited both the number af CTC:and the formaton of metatatic foci more eflectively compared to the lower dose.TUNEL assays revealed that R.IF trentment promotes apoptosis of tumor cells,with a more pronounced effect observed at the higher dose.Immuno-fluorescence experiments demonstrated that administering a higher dose of R.IF suppreses theеxprescion of Kindlin-1 more effectively in the tumor microenvironment.Although higher doses showed enhanced efficacy,they might also lesd to an increase in side efects.These findings underscore the promise and challenges of using R.IF at high doses for anti-tumor therspy.They highlight the criticnl importance of optimizing the dose of R.JP in the treatment of TNBC and provide valuable insights for its dinical application. 展开更多
关键词 In vito fow cytometry fluorescence imaging triple-negative breæst cancer circulating tumorælls Rujifang dose
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iDose4重建法结合低管电压及固定管电流在新生儿胸部CT检查中的应用
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作者 徐思雨 张倩云 边传振 《影像科学与光化学》 2025年第2期89-94,共6页
目的:探讨在新生儿胸部CT检查中,结合使用低管电压、固定管电流以及不同权重的iDose4重建技术对图像质量的影响,并评估其可行性。方法:搜集80例行CT检查的新生儿,随机分到A、B两组,A组采用自动曝光控制技术,B组采用固定管电流扫描(33 m... 目的:探讨在新生儿胸部CT检查中,结合使用低管电压、固定管电流以及不同权重的iDose4重建技术对图像质量的影响,并评估其可行性。方法:搜集80例行CT检查的新生儿,随机分到A、B两组,A组采用自动曝光控制技术,B组采用固定管电流扫描(33 mA),采用iDose^(4)重建法重建出1~7级不同权重的肺窗和纵隔窗图像,并对比分析图像质量。记录患儿的CTDIVOL,后依据回归模型计算出体型特异性剂量估算值(size specific dose estimate,SSDE),并对比分析。结果:A、B两组患儿iDose^(4)重建算法的最佳权重肺窗为3级,纵隔窗为4级;A、B组患儿CTDIVOL分别为(1.04±0.21)mGy和(0.91±0.18)mGy,A组较B组高12.5%(t=2.17,P=0.04);A、B组患儿的SSDE分别为(2.41±0.36)mGy和(2.07±0.32)mGy,A组较B组高15.4%(t=3.19,P<0.05);A、B组患儿CTDIVOL离散度分别为20.2%(0.21/1.04)和19.8%(0.18/0.91),A、B组患儿SSDE离散度分别为14.5%(0.36/2.41)和15.5%(0.32/2.07)。结论:在新生儿CT检查时推荐使用低管电压、低固定管电流及适当的重建算法权重相结合的方法进行扫描,同时,推荐采用SSDE评估新生儿的辐射剂量。 展开更多
关键词 辐射剂量 体型特异性剂量估算值 新生儿 胸部CT
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小儿风热清合剂(口服液)对幼年大鼠的安全性评价研究
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作者 李洋 刘妍 +5 位作者 宋志前 殷苗苗 田子琦 刘晓宁 王淳 宁张弛 《中国中医基础医学杂志》 2026年第1期154-161,共8页
目的通过幼年SD大鼠急性毒性及重复给药毒性试验,评价小儿风热清合剂(口服液,简称“小儿风热清”)的安全性。方法急性毒性试验采用最大给药量法(120 g/kg),观察给药后大鼠毒性反应。重复给药毒性试验分为低、中、高小儿风热清给药组,剂... 目的通过幼年SD大鼠急性毒性及重复给药毒性试验,评价小儿风热清合剂(口服液,简称“小儿风热清”)的安全性。方法急性毒性试验采用最大给药量法(120 g/kg),观察给药后大鼠毒性反应。重复给药毒性试验分为低、中、高小儿风热清给药组,剂量分别为12 g/kg、30 g/kg、60 g/kg。对幼年大鼠连续灌胃30 d,恢复期3周,检测指标包括一般状态、体质量、脏器系数、血液学指标、血液生化学指标、激素指标及病理组织切片。结果急性毒性试验在120 g/kg剂量下未出现明显与受试药物有关的毒副反应。重复给药毒性试验在不同剂量下均未出现明显与受试药物相关的毒性改变。结论小儿风热清在120 g/kg剂量(相当于临床剂量的100倍)下对幼年大鼠无明显急性毒性作用,重复给药30 d未见明显毒性反应的剂量为30 g/kg(相当于临床剂量的25倍)。 展开更多
关键词 小儿风热清 幼年大鼠 急性毒性 重复给药毒性 安全性评价
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不同参数设置对双侧乳腺癌螺旋断层放疗计划的影响研究
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作者 薛涛 何晓阳 +2 位作者 王斌 王佩烨 孙云川 《医疗卫生装备》 2026年第1期56-62,共7页
目的:研究设置不同的铅门宽度、螺距、调制因子对双侧乳腺癌(bilateral breast cancer,BBC)螺旋断层放疗(helical tomotherapy,HT)计划的影响。方法:回顾性选取2013年10月至2023年7月间于某院接受放疗的17例BBC患者的资料,分别设计不同... 目的:研究设置不同的铅门宽度、螺距、调制因子对双侧乳腺癌(bilateral breast cancer,BBC)螺旋断层放疗(helical tomotherapy,HT)计划的影响。方法:回顾性选取2013年10月至2023年7月间于某院接受放疗的17例BBC患者的资料,分别设计不同铅门宽度(1.0、2.5、5.0 cm)、螺距(0.215、0.287、0.430)、调制因子(2.0、2.5、3.0、3.5、4.0)的HT计划,同时其他参数保持一致,设计比较不同参数组合放疗计划的剂量学参数差异[包括计划靶区最大剂量D2、最小剂量D98、靶区覆盖度D95、V105以及适形度指数(conformity index,CI)和均匀性指数(homogeneity index,HI),危及器官(organs at risk,OAR)的剂量参数(双肺V5、V20、V30、Dmean,心脏V5、V20、V30、Dmean,肝脏Dmean)]以及治疗时间。使用SPSS 20.0软件进行统计学分析。结果:减小铅门宽度能够改善靶区的D98、D95、D2、D105、V105、HI,并且减少OAR的受照剂量,差异有统计学意义(P<0.05),但CI差异无统计学意义(P>0.05)。伴随着铅门宽度的减小,治疗时间成倍地增加,差异有统计学意义(P<0.05)。减小螺距能使靶区和OAR的照射剂量得到小幅改善,差异有统计学意义(P<0.05),但螺距的减小对治疗时间的影响较小。增大调制因子可以改善靶区和OAR的剂量学指标,差异有统计学意义(P<0.05),但调制因子为3.5和4.0的治疗计划剂量学指标差异较小。调制因子每增加0.5,平均治疗时间约增加15%,差异有统计学意义(P<0.05)。结论:在进行BBC HT计划设计时,设置铅门宽度为5.0 cm、螺距为0.215、调制因子为3.5时治疗计划的效果更佳。 展开更多
关键词 双侧乳腺癌 螺旋断层放疗 铅门宽度 螺距 调制因子 剂量分布
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