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Diagnostic challenges in alcohol use disorder and alcoholic liver disease 被引量:1
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作者 Luisa Vonghia Peter Michielsen +1 位作者 Geert Dom Sven Francque 《World Journal of Gastroenterology》 SCIE CAS 2014年第25期8024-8032,共9页
Alcohol use disorders represent a heterogeneous spectrum of clinical manifestations that have been defined by the Diagnostic and Statistical Manual of Mental Disorders-5. Excessive alcohol intake can lead to damage of... Alcohol use disorders represent a heterogeneous spectrum of clinical manifestations that have been defined by the Diagnostic and Statistical Manual of Mental Disorders-5. Excessive alcohol intake can lead to damage of various organs, including the liver. Alcoholic liver disease includes different injuries ranging from steatosis to cirrhosis and implicates a diagnostic assessment of the liver disease and of its possible complications. There is growing interest in the possible different tools for assessing previous alcohol consumption and for establishing the severity of liver injury, especially by noninvasive methods. 展开更多
关键词 Alcoholic liver disease Alcohol use disorder Diagnosis diagnostic and Statistical Manual of Mental Disorders-5 Screening tests Markers of previous alcohol consumption Non-invasive fibrosis assessment
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Evaluation of Appropriateness of Proton Pump Inhibitors (PPIs) Use in the Region of Sharjah, United Arab Emirates (UAE)
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作者 Osama H. Mohamed Ibrahim Mohamed E. A. Rashrash +3 位作者 Rand Albasha Reem Alani Sama Khadhum Sameh Soliman 《Pharmacology & Pharmacy》 2018年第6期149-156,共8页
Background: Proton pump inhibitors (PPIs) are drugs that reduce the production of acid in the stomach. Recently, the use of PPI has been increasing among communities, whether with or without prescription. As a part of... Background: Proton pump inhibitors (PPIs) are drugs that reduce the production of acid in the stomach. Recently, the use of PPI has been increasing among communities, whether with or without prescription. As a part of the healthcare team, the pharmacist should not only dispense medications but also ensure the appropriate use of these medications. Studies conducted within 16 countries showed substantial variation in the appropriateness of the use of PPI drugs. Aim: To evaluate the appropriateness of PPIs use in Sharjah, UAE based on surveys answered by pharmacists, physicians, and patients. Methods: A cross-sectional survey study was conducted on December 2017 at Sharjah, UAE as an example of information obtained from the Middle East. Two different surveys were conducted on physicians and pharmacists. Both Physicians and Pharmacists were chosen randomly from Yellow Pages. The results obtained from both studies were used to develop a patient’s survey, which was distributed among University of Sharjah students, their families and random people at Shopping Malls and Clinics. Results: The results obtained from the patients’ survey showed that ~39% of PPI users from the region of Sharjah are 25 - 44 years old. Approximately 79% are using PPI according to physicians’ prescriptions. Prescriptions’ duration is varied between 1 month (39%) and 6 months (22%), where 52% of PPI users ask their physicians to prescribe PPIs when needed. Suggested reasons for the use of PPI included inappropriate food habits (52%), use of other medications (16%) or bacterial infection (13%). Around 52% of the patients did not receive any recommendations regarding the deprescribing of PPIs. According to the pharmacists’ surveys, an average sale of 5 - 10 PPI packages is reported per day, and around 50% are sold without a prescription. Most pharmacists were not fully aware of the health conditions and side effects of PPI drugs. On the other hand, physicians’ surveys showed that PPIs were mainly prescribed in the case of GERD and ulcer and for a maximum of 2 - 4 weeks. Approximately 75% of physicians recommend changing regimen by reducing the dose and stopping in case of chronic use of PPIs. Conclusion: The results from this survey study indicated that even though most PPI consumers at Sharjah, UAE are well aware of the use of PPI drugs and they follow the instructions given by the Physicians’, there is some discrepancy in the information obtained by the physicians, pharmacists, and patients. The reason for this discrepancy may be attributed to the missing role of the pharmacists which is currently just dispensing the medications without appropriate counseling. Thus the appropriate role of the pharmacists should be implemented according to the known international guidelines. 展开更多
关键词 proton Pump Inhibitors Deprescribing APPROPRIATE use UNITED Arab Emirates (UAE)
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A COMPUTER SIMULATING OF MEASURING TISSUE TEMPERTURE USING DIAGNOSTIC ULTRASOUND
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《Chinese Journal of Biomedical Engineering(English Edition)》 1999年第4期114-115,共2页
关键词 MATLAB A COMPUTER SIMULATING OF MEASURING TISSUE TEMPERTURE USING diagnostic ULTRASOUND
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三维酰胺质子转移成像在原发性肝癌临床扫描可行性及图像质量评估中的初步研究
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作者 齐晓辉 王琦 +7 位作者 沈智威 段梦婷 刘响 潘江洋 范雪丽 贾丽涛 王亚宁 杜煜 《磁共振成像》 CAS CSCD 北大核心 2024年第3期163-169,共7页
目的 评估参数优化的三维酰胺质子转移加权(3 dimensions-amide proton transfer weighted,3D-APTw)成像在原发性肝癌扫描中的图像质量并分析其临床扫描的可行性。材料与方法 前瞻性招募2020年10月至2022年2月临床怀疑原发性肝癌患者,共... 目的 评估参数优化的三维酰胺质子转移加权(3 dimensions-amide proton transfer weighted,3D-APTw)成像在原发性肝癌扫描中的图像质量并分析其临床扫描的可行性。材料与方法 前瞻性招募2020年10月至2022年2月临床怀疑原发性肝癌患者,共109例。采用飞利浦3.0 T MRI设备进行扫描,分别采集T1WI、T2WI、弥散加权成像、酰胺质子转移加权(amide proton transfer weighted,APTw)及多期增强图像。机器自动生成经过B0校正的肝脏APTw图像。计算3D-APTw成像的扫描成功率及计算成功率。采用Kendall一致性系数对观察者内及观察者间主观评分进行一致性分析,对主观评分3分以上的病例测量3D-APTw图像的信噪比(signal-to-noise ratio,SNR)、肿瘤对比噪声比(contrast-to-noise ratio,CNR)、肿瘤及肝实质的APTw值并计算各参数值的变异系数,采用组内相关系数进行观察者内及观察者间可重复性测量的一致性分析。结果 109例患者中有11例患者3D-APTw图像中病变区域存在信号缺失,扫描成功率为89.91%(98/109),剩余98例患者中78例3D-APTw图像的主观评分为3分以上,计算成功率为71.56%(78/109)。观察者内及观察者间图像质量主观评分一致性分别为0.771和0.692,P<0.01。肿瘤组织APTw值观察者内及观察者间ICC分别为0.822和0.811,肝实质APTw值、SNR及CNR观察者ICC分别为0.675、0.634、0.666,肝实质APTw值、SNR及CNR观察者间ICC分别为0.614、0.290、0.560。肿瘤组织APTw值高于肝实质[(2.55±0.08)%vs.(1.45±0.07)%],两者间差异有统计学意义(P<0.001)。肿瘤组织和肝实质APTw值的变异系数分别为30.40%和44.40%。SNR和CNR为25.92±18.50和3.35±3.20。SNR变异系数为71.40%,CNR变异系数为90.00%。结论 参数优化后的3D-APTw成像可以用于原发性肝癌的临床扫描,但容易受呼吸运动、胆囊或血管的影响而出现信号缺失或伪影,在参数设置及成像技术上仍有需要改进和提高的空间,以进一步优化其图像质量。 展开更多
关键词 原发性肝癌 诊断可行性 图像质量 三维酰胺质子转移成像 磁共振成像
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FibroScan、MRI-PDFF和FAST评分识别高危非酒精性脂肪性肝炎患者临床应用研究
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作者 杨逸铭 李晓环 +4 位作者 刘玉品 欧金龙 黎胜 石美凤 汪印强 《实用肝脏病杂志》 CAS 2024年第5期701-704,共4页
目的探讨瞬时弹性成像(FibroScan)、磁共振质子密度脂肪分数(MRI-PDFF)和FAST评分识别高危非酒精性脂肪性肝炎(NASH)患者的应用价值。方法2017年6月~2021年12月我院诊治的非酒精性脂肪肝病(NAFLD)患者107例,均接受肝活检和MRI-PDFF、Fib... 目的探讨瞬时弹性成像(FibroScan)、磁共振质子密度脂肪分数(MRI-PDFF)和FAST评分识别高危非酒精性脂肪性肝炎(NASH)患者的应用价值。方法2017年6月~2021年12月我院诊治的非酒精性脂肪肝病(NAFLD)患者107例,均接受肝活检和MRI-PDFF、FibroScan和血清学检查,计算FAST、FIB-4和APRI指数。采用单因素和多因素Logistic回归分析,应用受试者工作特征(ROC)曲线分析指标识别高危NASH患者的诊断效能。结果在107例NAFLD患者中,经肝组织病理学检查诊断高危非酒精性脂肪性肝炎(NASH)患者13例(12.1%),单纯性脂肪肝和非高危NASH患者94例(87.9%);高危NASH组LSM、FAST评分和APRI指数显著高于非高危组(P<0.05);多因素Logistic回归分析显示,FibroScan检测的肝脏硬度(LSM)是高危NASH患者的独立影响因素(P<0.05);ROC曲线分析显示LSM、FAST和APRI识别高危NASH患者有统计学意义(P<0.05),其曲线下面积(AUC)分别为0.795、0.713和0.682,以LSM的诊断效能最优,其排除截断点诊断的敏感度和特异度分别为92.3%和54.3%,而纳入截断点诊断则为53.8%和90.4%。结论对于FibroScan检测诊断的NAFLD患者,其LSM也同期升高高度提示NASH的存在,应进一步检查,以期早期干预。 展开更多
关键词 非酒精性脂肪性肝炎 瞬时弹性成像 磁共振质子密度脂肪分数 FAST评分 诊断
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斜冠状位质子加权脂肪抑制成像对前交叉韧带撕裂的价值分析
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作者 刘晓辉 邓煜 《当代医学》 2024年第2期86-90,共5页
目的探讨斜冠状位质子加权脂肪抑制成像(PDWI)对前交叉韧带撕裂的诊断价值。方法选取2020年7月至2022年3月瑞金市人民医院收治的82例临床疑似前交叉韧带损伤患者作为研究对象,均进行常规斜矢状位MRI、斜冠状位PDWI。以关节镜检查为金标... 目的探讨斜冠状位质子加权脂肪抑制成像(PDWI)对前交叉韧带撕裂的诊断价值。方法选取2020年7月至2022年3月瑞金市人民医院收治的82例临床疑似前交叉韧带损伤患者作为研究对象,均进行常规斜矢状位MRI、斜冠状位PDWI。以关节镜检查为金标准,比较常规斜矢状位MRI与斜冠状位PDWI诊断前交叉韧带撕裂的诊断效能及准确度。结果斜冠状位PDWI诊断前交叉韧带撕裂的灵敏度、特异度、阳性预测值、阴性预测值、Kappa值均高于常规斜矢状位MRI,但差异无统计学意义;斜冠状位PDWI诊断前交叉韧带撕裂准确度高于常规斜矢状位MRI,差异有统计学意义(P<0.05)。斜冠状位PDWI诊断前交叉韧带损伤分级的准确度为78.05%,高于常规斜矢状位MRI的62.20%,差异有统计学意义(P<0.05)。结论在常规斜矢状位MRI的基础上应用斜冠状位PDWI对前交叉韧带撕裂及损伤分级的诊断价值更高。 展开更多
关键词 斜冠状位 质子加权脂肪抑制成像 前交叉韧带撕裂 诊断价值
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Land use and landscape pattern change: a linkage to the construction of the Qinghai-Xizang Highway 被引量:9
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作者 YAN Jianzhong, ZHANG Yili, LIU Linshan, LIU Yanhua2, ZHENG Du (1. Inst. of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China 2. The Ministry of Science and Technology, Beijing 100101, China 3. College of Resources and Enviro 《Journal of Geographical Sciences》 SCIE CSCD 2002年第3期253-265,共13页
Based on digital land use data from 1995 to 2000 and road data, the land use and landscape changes of Golmud, Qumaleb and Zhidoi are studied on a macro-scale. Land use and landscape changes in highway buffer zones and... Based on digital land use data from 1995 to 2000 and road data, the land use and landscape changes of Golmud, Qumaleb and Zhidoi are studied on a macro-scale. Land use and landscape changes in highway buffer zones and city expansion are special subjects. A new formula is used to define the exact degree of dynamic land use. To adequately define land use and landscape pattern changes, the buffer zones, illustrating the changes at different distances from the road, are recognized with ArcGIS 8.1 software. Prominent changes took place in land use and landscape patterns from 1995 to 2000, and the area of built-up land increased by 323.8%. The comprehensive degree of dynamic land use is 2.25, and the degree of dynamic land use of built-up land is the highest, followed by cultivated land. Woodland has the lowest value. The used degree index of land resources declined by 38.8 from 1995 to 2000. Landscape changed dramatically which influenced ecological processes immensely. Different from the corridor effect of other traffic routes, the corridor effect of this section of road is not obvious and its “point” radiation effect can be easily seen. The expanding range of Golmud City is confined to a 3 km buffer, while for Wudaoliang, it is 1 km. No land use change happened in the Nanshankou buffer. 展开更多
关键词 land use change comprehensive index of the degree of land use diagnostic index of landscape degree of dynamic land use Qinghai-Xizang Highway
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Electrogastrography: Poor correlation with antro-duodenal manometry and doubtful clinical usefulness in adults 被引量:3
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作者 Shahab Abid Greger Lindberg 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第38期5101-5107,共7页
AIM: To investigate if there is a correlation between electrical activity measured by electrogastrography (EGG) and contractile activity of the stomach as measured by antroduodenal manometry (ADM). We also studied whe... AIM: To investigate if there is a correlation between electrical activity measured by electrogastrography (EGG) and contractile activity of the stomach as measured by antroduodenal manometry (ADM). We also studied whether the underlying motility disorder could be predicted from EGG parameters. METHODS: We compared 21 parameters measured from EGG with 8 parameters measured from ADM. The ability of EGG to identify the underlying diagnosis was tested by comparing EGG parameters for each diagnosis group against other patients. The study comprised recordings from 148 patients and 125 females. Their median age was 45 (range 17-76) years. RESULTS: We found few and weak correlations between EGG and ADM. Specifically the correlation between parameters reflecting the response to meal was poor (r = -0.07, P = 0.39). The discriminatory power of EGG for underlying motility disorder was also low. Patients with slow transit constipation (STC) showed a lower postprandial power in normogastric (3.7 ± 0.5 vs 4.0 ± 0.5) and tachygastric (3.5 ± 0.4 vs 3.7 ± 0.4) regions, a lower percentage of time with normogastria [87.2 (56.5-100)% vs 95.7 (0-100)%], and a higher percentage of time with tachygastria [9.3 (0-33)% vs 3.5 (0-100)%] and bradygastria [1.8 (0-20)% vs 0 (0-17.1)%]. Patients with irritable bowel syndrome had a higher percentage of time with normogastria [96.5 (62.5-100)% vs 93.3 (0-100)%] and a less unstable dominant frequency as measured by the instability coefficient [15 (3-77) vs 24 (2-72)]. CONCLUSION: EGG and ADM seem to measure different aspects of gastric motor activity but cannot show a spatial correlation. The diagnostic value of EGG is poor, but EGG may have some value for the identification of patients with STC. 展开更多
关键词 Antroduodenal manometry CORRELATION diagnostic use ELECTROGASTROGRAPHY Functional bowel disorders PHYSIOPATHOLOGY
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Generating Proton Beams Exceeding 10 MeV Using High Contrast 60TW Laser 被引量:1
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作者 Yi-Xing Geng Qing-Liao +14 位作者 Yin-Ren Shou Jun-Gao Zhu Xiao-Han Xu Min-Jian Wu Peng-Jie Wang Dong-Yu Li Tong-Yang Rong-Hao Hu Da-Hui Wang Yan-Ying Zhao Wen Jun Ma Hai-Yang Lu Zhong-Xi Yuan Chen-Lin Xue-Qing Yan 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第9期28-32,共5页
A prototype of a laser driven proton accelerator is built at Peking University. Protons exceeding IOMeV are accelerated from micrometer-thick aluminum targets irradiated by tightly focused laser pulse with 1.8 J energ... A prototype of a laser driven proton accelerator is built at Peking University. Protons exceeding IOMeV are accelerated from micrometer-thick aluminum targets irradiated by tightly focused laser pulse with 1.8 J energy and 30fs duration. The beam energy spectrum and charge distribution are measured by a Thomson parabola spectrometer and radiochromic fihn stacks. The sensitivity of proton cut-off energy to the focusing of the laser beam, the pulse duration, and the foil thickness are systematically investigated in the experiments. Stable proton beams have been produced with an optimized parameter set, providing a cornerstone for the future applications of laser accelerated protons. 展开更多
关键词 Generating proton Beams Exceeding 10 MeV Using High Contrast 60TW Laser
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The application of proton spectrometers at the SG-III facility for ICF implosion areal density diagnostics 被引量:1
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作者 Xing Zhang Jianhua Zheng +11 位作者 Ji Yan Zhenghua Yang Ming Su Yudong Pu Pin Yang Xufei Xie Li Chen Ming Chen Tianxuan Huang Shao'en Jiang Shenye Liu Jiamin Yang 《High Power Laser Science and Engineering》 SCIE CAS CSCD 2015年第4期10-18,共9页
Charged particle diagnostics is one of the required techniques for implosion areal density diagnostics at the SG-III facility.Several proton spectrometers are under development, and some preliminary areal density diag... Charged particle diagnostics is one of the required techniques for implosion areal density diagnostics at the SG-III facility.Several proton spectrometers are under development, and some preliminary areal density diagnostics have been carried out. The response of the key detector, CR39, to charged particles was investigated in detail. A new track profile simulation code based on a semi-empirical model was developed. The energy response of the CR39 detector was calibrated with the accelerator protons and alphas from a241 Am source. A proton spectrometer based on the filtered CR39 detector was developed, and D–D primary proton measurements were implemented. A step range filter spectrometer was developed,and preliminary areal density diagnostics was carried out. A wedged range filter spectrometer array made of Si with a higher resolution was designed and developed at the SG-III facility. A particle response simulation code by the Monte Carlo method and a spectra unfolding code were developed. The capability was evaluated in detail by simulations. 展开更多
关键词 areal density diagnosticS CR39 detector SRF proton SPECTROMETER WRF proton SPECTROMETER
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miniSCIDOM: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches
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作者 A.Corvino M.Reimold +10 位作者 E.Beyreuther F.-E.Brack F.Kroll J.Pawelke J.D.Schilz M.Schneider U.Schramm M.E.P.Umlandt K.Zeil T.Ziegler J.Metzkes-Ng 《High Power Laser Science and Engineering》 SCIE CAS CSCD 2024年第2期41-50,共10页
Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology o... Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material analysis.Being spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample properties.The rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online feedback.Here we present the scintillator-based miniSCIDOM detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 mGy.The detector performance is tested at a proton therapy cyclotron and an LPA proton source.The experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour. 展开更多
关键词 beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate
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The study of complex focussing acoustic field of a convex phased array probe used in ultrasonic diagnostic B-scanner
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作者 LANG Yifu,BU Shuzhong, JIANG Nanxiang and CAI Chongcheng(Harbin Shipbuilding Engineering Institute ) 《Chinese Journal of Acoustics》 1991年第2期167-175,共9页
This paper reports a study of complex focussing acoustic fields of a convex phased array probe widely used in ultrasonic diagnostic B-scanner. The time delay necessary for electronic focussing and for geometric focuss... This paper reports a study of complex focussing acoustic fields of a convex phased array probe widely used in ultrasonic diagnostic B-scanner. The time delay necessary for electronic focussing and for geometric focussing of complex focussing is given. By means of Helmholtz's integral formula, the expressions of acoustic fields were obtained for the electronic focussing and complex focussing.With Simpson's numerical integral, a great deal of computations was carried out with an 86 / 330 computer. By means of using different parameters, an optimum focal range and beam width of a 4 sequences electronic and complex focussing acoustic system was selected. With an EUB-40 ultrasound diagnostic B-scanner produced by the Hitachi company, the lateral focussing acoustic field and lateral resolution in an echoic tank were photographed by latticing method and the experimental result is consistent with the theory. 展开更多
关键词 The study of complex focussing acoustic field of a convex phased array probe used in ultrasonic diagnostic B-scanner
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Comparison of diagnostic value of TIRADS,BSRTC,BRAF^(V600E) mutation detection and their combined use in differentiating thyroid nodules
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作者 张于芝 《China Medical Abstracts(Internal Medicine)》 2016年第3期147-148,共2页
Objective To compare the diagnostic efficiency of the thyroid imaging reporting and data system(TIRADS),the Bethesda system for reporting thyroid cytopathology(BSRTC)and BRAFV600Edetection,and their combined use in th... Objective To compare the diagnostic efficiency of the thyroid imaging reporting and data system(TIRADS),the Bethesda system for reporting thyroid cytopathology(BSRTC)and BRAFV600Edetection,and their combined use in the differentiation between benign and malignant thyroid nodules.Methods One hundred 展开更多
关键词 FNAC Comparison of diagnostic value of TIRADS BSRTC BRAF V600E mutation detection and their combined use in differentiating thyroid nodules
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难治性胃食管反流病诊断方法的研究进展 被引量:22
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作者 宋宏伟 朱凌云 《世界华人消化杂志》 CAS 北大核心 2012年第19期1742-1746,共5页
众多学者把质子泵抑制剂(proton pump inhibitors,PPIs)治疗不应答的胃食管反流病(gastroesophageal reflux disease,GERD)称为难治性胃食管反流病,本病是当前消化系统疾病谱中最为顽固的治疗难题之一.近年来众多研究者运用多种诊察手... 众多学者把质子泵抑制剂(proton pump inhibitors,PPIs)治疗不应答的胃食管反流病(gastroesophageal reflux disease,GERD)称为难治性胃食管反流病,本病是当前消化系统疾病谱中最为顽固的治疗难题之一.近年来众多研究者运用多种诊察手段来研究本病,希望找到该病的发病机制.本文就最近国内外有关难治性GERD的诊断方案,发病机制及相关研究结果等内容作一综述. 展开更多
关键词 难治性胃食管反流病 质子泵抑制剂 诊断 发病机制
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质子交换膜燃料电池水淹和膜干故障诊断研究综述 被引量:21
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作者 张雪霞 蒋宇 +1 位作者 孙腾飞 陈维荣 《西南交通大学学报》 EI CSCD 北大核心 2020年第4期828-838,864,共12页
质子交换膜燃料电池水淹和膜干是其在运行过程中最常见的故障.首先,阐述了质子交换膜燃料电池中水的产生和传输机理,概括了水淹和膜干故障的影响因素,列举并分析了基于电压、压力降和阻抗的水淹和膜干诊断指标及各自的优缺点,并从内部... 质子交换膜燃料电池水淹和膜干是其在运行过程中最常见的故障.首先,阐述了质子交换膜燃料电池中水的产生和传输机理,概括了水淹和膜干故障的影响因素,列举并分析了基于电压、压力降和阻抗的水淹和膜干诊断指标及各自的优缺点,并从内部结构和电荷传输方面介绍了水淹和膜干对质子交换膜燃料电池的危害;其次,讨论了水淹和膜干故障基于模型、基于实验和基于数据驱动的3种诊断方法及其适用范围,另外分析了缓解水淹和膜干故障的常用措施;最后,对水淹和膜干故障进行了总结和展望,并指出基于数据驱动的在线诊断方法、适于故障诊断的模型建立、大尺度电堆及多堆间水淹和膜干故障的诊断及高效精准的故障诊断指标的探索有待深入研究. 展开更多
关键词 质子交换膜燃料电池 水淹和膜干 诊断指标 诊断方法 缓解措施
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质子磁共振波谱分析对脑多发性硬化的诊断价值 被引量:1
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作者 朱敏 刘鹤 +4 位作者 宋先东 魏秀芳 巩晓艳 韦洁如 孙继平 《中国现代医生》 2017年第5期92-94,共3页
目的评价质子磁共振波谱分析对脑多发性硬化的诊断价值。方法选取我院2015年4月~2016年11月收治的20例脑多发性硬化患者作为实验组、选取同期我院正常健康人群作为对照组。两组均进行质子磁共振波谱检查,采用SPSS 2.0.0统计学软件对两... 目的评价质子磁共振波谱分析对脑多发性硬化的诊断价值。方法选取我院2015年4月~2016年11月收治的20例脑多发性硬化患者作为实验组、选取同期我院正常健康人群作为对照组。两组均进行质子磁共振波谱检查,采用SPSS 2.0.0统计学软件对两组研究对象脑部代谢产物氮乙酰天门冬氨酸/肌酸浓度比、胆碱/肌酸浓度比肌酸浓度值等参数指标进行统计分析。结果实验组脑部代谢产物氮乙酰天门冬氨酸/肌酸浓度值、胆碱/肌酸浓度值分别为(139±0.44)/(11.98±0.83),正常对照组脑部代谢产物氮乙酰天门冬氨酸/肌酸浓度值、胆碱/肌酸浓度值分别为(1.90±0.50)、(1.47±0.35),实验组脑部代谢产物氮乙酰天门冬氪酸/肌酸浓度值显著低于对照组(P<0.05),胆碱/肌酸浓度值显著高于对照组(P<0.05)。结论质子磁共振波谱分析对脑多发性硬化的诊断价值较高。 展开更多
关键词 质子磁共振波谱 脑多发性硬化 诊断价值
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质子成像法测量电容线圈靶磁场 被引量:1
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作者 韩波 梁雅琼 《物理学报》 SCIE EI CAS CSCD 北大核心 2020年第17期158-166,共9页
质子背光成像技术是一种诊断等离子体电磁场的重要诊断手段.当质子穿过等离子体的电磁场,质子受洛伦兹力影响在成像板上重新分布.如何从质子成像结果中重构电磁场是一个非常重要的研究课题.本文以激光驱动电容线圈靶为例介绍和对比了粒... 质子背光成像技术是一种诊断等离子体电磁场的重要诊断手段.当质子穿过等离子体的电磁场,质子受洛伦兹力影响在成像板上重新分布.如何从质子成像结果中重构电磁场是一个非常重要的研究课题.本文以激光驱动电容线圈靶为例介绍和对比了粒子追踪法和流量分析法这两种通过质子成像结果重构磁场的方法.激光驱动电容线圈靶通过激光打靶在电容靶两侧产生电势,然后很强的电流流过线圈,最后产生高达千特斯拉的感应磁场,在激光等离子体实验中这是一种重要的产生磁场的手段.本工作中先使用粒子追踪法在不同强度的理论磁场环境下得到质子成像结果,然后使用流量分析法从这些理论质子成像结果重构磁场,最后对比理论磁场和重构磁场以获得两种方法的优缺点.粒子追踪法可以重现实验中质子源、等离子体磁场和成像板的布局结构,但是依赖于精确的理论磁场的计算和庞大的计算量来模拟质子的轨迹,并需要不断修正理论磁场来获得最接近实验结果的模拟结果.流量分析法可以直接从实验的质子成像结果重构磁场结构.但是,流量分析法只适用于磁场较小的情况,当磁场较大时其重构的磁感应强度会误差较大.可以使用一个无量纲参量μ来衡量质子穿过作用区域单位长度后在成像板上的偏折距离,流量分析法适用于μ<<1的情况.并且靶的结构在质子成像上形成的阴影区域也会造成磁场重构时磁场结构的失真. 展开更多
关键词 质子背光成像 激光等离子体 磁场产生 诊断技术
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磁敏感加权成像检查+氢质子磁共振波谱成像对脑胶质瘤分级诊断效能的影响 被引量:5
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作者 崔振华 《黑龙江医学》 2022年第6期743-744,747,共3页
目的:研究磁敏感加权成像(SWI)检查+氢质子磁共振波谱(1H-MRS)成像对脑胶质瘤分级的诊断效能。方法:选取2019年5月—2020年5月安阳市肿瘤医院脑收治的94例胶质瘤患者,均行SWI、1H-MRS检查,以世界卫生组织(WHO)分级方法为“金标准”。比... 目的:研究磁敏感加权成像(SWI)检查+氢质子磁共振波谱(1H-MRS)成像对脑胶质瘤分级的诊断效能。方法:选取2019年5月—2020年5月安阳市肿瘤医院脑收治的94例胶质瘤患者,均行SWI、1H-MRS检查,以世界卫生组织(WHO)分级方法为“金标准”。比较脑胶质瘤不同分级的SWI、1H-MRS检查参数[磁敏感信号(ITSS)评分、胆碱化合物(Cho)/肌酸(Cr)、N-乙酰天门冬氨酸(NAA)/Cr、NAA/Cho],比较SWI、1H-MRS检查及联合检查脑胶质瘤分级的诊断结果及诊断效能(灵敏度、特异度、准确度)。结果:不同脑胶质瘤分级NAA/Cho比较,差异无统计学意义(P>0.05);高级脑胶质瘤患者ITSS评分、Cho/Cr高于低级患者,NAA/Cr低于低级患者,差异有统计学意义(t=13.989,17.845,12.675,P<0.05);联合检查高级脑胶质瘤灵敏度93.75%高于SWI检查70.83%、1H-MRS检查72.92%,差异有统计学意义(χ^(2)=9.347,P<0.05);联合检查高级脑胶质瘤特异度为82.61%、准确度为88.30%,SWI检查特异度为86.96%、准确度为78.72%,1H-MRS检查特异度为84.78%、准确度为78.72%,三者比较差异无统计学意义(P>0.05)。结论:SWI检查+1H-MRS成像能准确区分高、低级脑胶质瘤,提高诊断效能,有助于临床治疗方案的制定。 展开更多
关键词 磁敏感加权成像 氢质子磁共振波谱 脑胶质瘤分级 诊断效能
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反冲质子磁分析技术的研究进展
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作者 蒋世伦 祁建敏 周林 《核技术》 CAS CSCD 北大核心 2011年第10期785-790,共6页
反冲质子磁分析技术作为探测聚变中子能谱的新技术,具有能量分辨率和信噪比高的优点,适合混合干扰和宽量程中子注量率条件下的测量,已经成为聚变装置中子诊断的重要手段。介绍了国际上几个大科学装置研制的反冲质子磁分析谱仪和实验结果... 反冲质子磁分析技术作为探测聚变中子能谱的新技术,具有能量分辨率和信噪比高的优点,适合混合干扰和宽量程中子注量率条件下的测量,已经成为聚变装置中子诊断的重要手段。介绍了国际上几个大科学装置研制的反冲质子磁分析谱仪和实验结果,磁质子反冲谱仪(MPR),磁分析系统使用两块分离的电磁铁,能量分辨率达2.5%;磁反冲谱仪(MRS)磁分析系统使用永磁铁,能测量6–32 MeV范围内的中子能谱,能量分辨率3%。中国工程物理研究院研制的反冲质子磁分析谱仪,使用0.79 T的永磁铁,探测效率为6.2×10-6 cm2。实验表明,磁分析系统的能量分辨率可达1.6%–2.1%。 展开更多
关键词 反冲质子 磁分析 聚变中子诊断
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Weibel不稳定性自生电磁场对探针质子束的偏转作用研究 被引量:5
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作者 杜报 蔡洪波 +3 位作者 张文帅 陈京 邹士阳 朱少平 《物理学报》 SCIE EI CAS CSCD 北大核心 2019年第18期199-207,共9页
Weibel不稳定性的自生电磁场对于等离子体能量输运、无碰撞冲击波形成等物理过程具有关键的影响.实验上往往采用质子束照相来诊断其电磁场结构.一般认为,探针质子束的轨迹偏转主要来自于磁场,而自生电场的作用被认为可忽略不计.本文利... Weibel不稳定性的自生电磁场对于等离子体能量输运、无碰撞冲击波形成等物理过程具有关键的影响.实验上往往采用质子束照相来诊断其电磁场结构.一般认为,探针质子束的轨迹偏转主要来自于磁场,而自生电场的作用被认为可忽略不计.本文利用三维粒子模拟程序研究了典型参数下的Weibel不稳定性发展过程,并使用径迹追踪法评估了Weibel不稳定性的质子束照相过程中电场和磁场对探针质子束的偏转作用.对比分析发现,引起探针质子束偏转的主要因素并不是磁场,而是过去研究中常被忽略的电场.主要原因为:Weibel不稳定性的自生磁场往往成管状结构,在使用探针质子束对其进行侧向照相时,磁场的作用会被自身中和并抵消.该认识将有助于深入理解Weibel不稳定性质子照相的实验结果. 展开更多
关键词 Weibel不稳定性 质子束照相 电磁场诊断 粒子模拟
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