目的探讨1.5 T磁共振成像(magnetic resonance imaging,MRI)与64排多层螺旋计算机体层成像(computed tomography,CT)对脊柱骨折的诊断价值。方法方便选取2021年1月—2022年12月泰兴市第二人民医院收治的82例疑似脊柱骨折患者作为研究对...目的探讨1.5 T磁共振成像(magnetic resonance imaging,MRI)与64排多层螺旋计算机体层成像(computed tomography,CT)对脊柱骨折的诊断价值。方法方便选取2021年1月—2022年12月泰兴市第二人民医院收治的82例疑似脊柱骨折患者作为研究对象,均予1.5 T MRI与64排多层螺旋CT检查,以手术结果为金标准,评估两种技术对脊柱骨折的诊断效能,并分析其对脊柱骨折分型的诊断价值。结果1.5 T MRI对脊柱骨折诊断的准确度、灵敏度与64排螺旋CT比较,差异无统计学意义(P均>0.05)。两种方法与金标准一致性均较好(kappa值≥0.75)。1.5 T MRI对脊柱骨折A、B、C型分型诊断整体符合率为97.56%,高于64排多层螺旋CT的86.59%,差异有统计学意义(χ^(2)=7.111,P<0.05)。结论1.5 T MRI与64排螺旋CT对脊柱骨折诊断效能相当,但1.5 T MRI的分型诊断效能更高。展开更多
目的探讨肝癌(HCC)1.5 T MR成像特征与病理特点的相关性。方法采用回顾性总结研究方法,选取诊治的HCC患者136例作为病例组,同期收集非HCC患者24例作为对照组,记录两组患者的1.5 T MR成像特征,同时记录病例组患者的病理特点并进行相关性...目的探讨肝癌(HCC)1.5 T MR成像特征与病理特点的相关性。方法采用回顾性总结研究方法,选取诊治的HCC患者136例作为病例组,同期收集非HCC患者24例作为对照组,记录两组患者的1.5 T MR成像特征,同时记录病例组患者的病理特点并进行相关性分析。结果两组的肝左叶体积指数与肝右叶体积指数对比无显著差异(P>0.05),病例组的肝内再生结节形成和肝实质网格状改变发生率显著高于对照组(P<0.05)。在病例组中,T1WI序列检出病灶高信号31例,等信号21例,低信号84例;T2WI序列检出病灶高信号110例,等信号6例,低信号20例。病例组的ADC值为(1.10±0.24)×10^-3 mm^2/s,对照组为(1.78±0.34)×10^-3 mm^2/s,病例组显著低于对照组(t=9.394,P=0.000)。当ADC临界值设为1.40×10^-3 mm^2/s时,ROC曲线下面积为0.789,诊断HCC的敏感度为70.0%和81.2%。直线相关分析显示病例组的MR ADC值与肝内再生结节形成、肝实质网格状改变、T1WI低信号与T2WI高信号有显著相关性(P<0.05)。结论在HCC 1.5 T MR成像中,磁共振扩散成像(DWI)的应用具有较好的诊断价值,可反映患者的病理特征与常规MR信号特征,可成为诊断HCC的一种有效手段。展开更多
We present a conceptual configuration of a high-temperature superconducting（HTS）magnet made from REBCO（Re=Rare Earth,B=Barium,C=Copper,O=Oxide）annular plates,called a Bitter-like HTS magnet,which can operate in pe...We present a conceptual configuration of a high-temperature superconducting（HTS）magnet made from REBCO（Re=Rare Earth,B=Barium,C=Copper,O=Oxide）annular plates,called a Bitter-like HTS magnet,which can operate in persistent current mode without joint resistance and can be excited by a flux pump and without current leads and a persistent power supply.An REBCO annular magnet which can generate 1.5 T corresponding to the operating current density 80%of critical current density of the magnet at an operating temperature of65 K is conceptually designed.Then the thermal stability of the magnet is numerically simulated by Comsol software.Whein a piece of RBCO annular plate quenches,the maximum released energy is its stored energy because each REBCO annular plate in the Bitter-like magnet is in parallel.To calculate the stored energy in the REBCO annular plate,the inductance of every annular plate,including self-inductance and mutual inductance,is calculated.Compared with the minimum quench energy（MQE）and stored energy in one REBCO annular plate,the stored energy in one REBCO annular plate is always smaller than the MQE,and the REBCO annular plate will not be damaged even though the stored energy in the REBCO annular plate is fully released,which indicates that this 1.5 T Bitter-like magnet has the property of self-protection.展开更多
文摘目的探讨1.5 T磁共振成像(magnetic resonance imaging,MRI)与64排多层螺旋计算机体层成像(computed tomography,CT)对脊柱骨折的诊断价值。方法方便选取2021年1月—2022年12月泰兴市第二人民医院收治的82例疑似脊柱骨折患者作为研究对象,均予1.5 T MRI与64排多层螺旋CT检查,以手术结果为金标准,评估两种技术对脊柱骨折的诊断效能,并分析其对脊柱骨折分型的诊断价值。结果1.5 T MRI对脊柱骨折诊断的准确度、灵敏度与64排螺旋CT比较,差异无统计学意义(P均>0.05)。两种方法与金标准一致性均较好(kappa值≥0.75)。1.5 T MRI对脊柱骨折A、B、C型分型诊断整体符合率为97.56%,高于64排多层螺旋CT的86.59%,差异有统计学意义(χ^(2)=7.111,P<0.05)。结论1.5 T MRI与64排螺旋CT对脊柱骨折诊断效能相当,但1.5 T MRI的分型诊断效能更高。
文摘目的探讨肝癌(HCC)1.5 T MR成像特征与病理特点的相关性。方法采用回顾性总结研究方法,选取诊治的HCC患者136例作为病例组,同期收集非HCC患者24例作为对照组,记录两组患者的1.5 T MR成像特征,同时记录病例组患者的病理特点并进行相关性分析。结果两组的肝左叶体积指数与肝右叶体积指数对比无显著差异(P>0.05),病例组的肝内再生结节形成和肝实质网格状改变发生率显著高于对照组(P<0.05)。在病例组中,T1WI序列检出病灶高信号31例,等信号21例,低信号84例;T2WI序列检出病灶高信号110例,等信号6例,低信号20例。病例组的ADC值为(1.10±0.24)×10^-3 mm^2/s,对照组为(1.78±0.34)×10^-3 mm^2/s,病例组显著低于对照组(t=9.394,P=0.000)。当ADC临界值设为1.40×10^-3 mm^2/s时,ROC曲线下面积为0.789,诊断HCC的敏感度为70.0%和81.2%。直线相关分析显示病例组的MR ADC值与肝内再生结节形成、肝实质网格状改变、T1WI低信号与T2WI高信号有显著相关性(P<0.05)。结论在HCC 1.5 T MR成像中,磁共振扩散成像(DWI)的应用具有较好的诊断价值,可反映患者的病理特征与常规MR信号特征,可成为诊断HCC的一种有效手段。
基金Supported by the Fundamental Research Funds for the Central Universities under Grant No 2018MS004
文摘We present a conceptual configuration of a high-temperature superconducting（HTS）magnet made from REBCO（Re=Rare Earth,B=Barium,C=Copper,O=Oxide）annular plates,called a Bitter-like HTS magnet,which can operate in persistent current mode without joint resistance and can be excited by a flux pump and without current leads and a persistent power supply.An REBCO annular magnet which can generate 1.5 T corresponding to the operating current density 80%of critical current density of the magnet at an operating temperature of65 K is conceptually designed.Then the thermal stability of the magnet is numerically simulated by Comsol software.Whein a piece of RBCO annular plate quenches,the maximum released energy is its stored energy because each REBCO annular plate in the Bitter-like magnet is in parallel.To calculate the stored energy in the REBCO annular plate,the inductance of every annular plate,including self-inductance and mutual inductance,is calculated.Compared with the minimum quench energy（MQE）and stored energy in one REBCO annular plate,the stored energy in one REBCO annular plate is always smaller than the MQE,and the REBCO annular plate will not be damaged even though the stored energy in the REBCO annular plate is fully released,which indicates that this 1.5 T Bitter-like magnet has the property of self-protection.
