目的:对比三维多回波恢复梯度回波(3D MERGE)、三维可变反转角快速自旋回波(3D SPACE STIR)序列在腰椎间盘突出症(LDH)检查中的应用效果。方法:选择2020年1月~2022年11月收治的135例LDH患者,回顾性分析患者临床和磁共振成像(MRI)资料,...目的:对比三维多回波恢复梯度回波(3D MERGE)、三维可变反转角快速自旋回波(3D SPACE STIR)序列在腰椎间盘突出症(LDH)检查中的应用效果。方法:选择2020年1月~2022年11月收治的135例LDH患者,回顾性分析患者临床和磁共振成像(MRI)资料,所有患者均接受常规MRI扫描及3D MERGE、3D SPACE STIR序列扫描,对比3D MERGE、3D SPACE STIR序列测量神经根直径的一致性,评价两种序列的图像质量参数[信噪比(SNR)、对比噪声比(CNR)]、图像清晰度评分。结果:3D MERGE和3D SPACE STIR序列测量的L3~S1神经根直径比较差异无统计学意义(P>0.05),且两组序列测量的L3、L4、L5和S1直径均显示出较高相关性(r=0.957,0.986,0.975,0.972,P<0.05);3D MERGE序列的SNR及CNR均高于3D SPACE STIR序列,神经根显示分级、图像清晰度评分优于3D SPACE STIR序列,差异有统计学意义(P<0.05)。结论:3D MERGE、3D SPACE STIR序列在LDH神经根直径测量中具有极高一致性,3D MERGE序列较3D SPACE STIR序列能够更清晰显示神经跟的解剖形态,图像质量更好。展开更多
3D printing stands at the forefront of transforming space exploration,offering unprecedented on-demand and rapid manufacturing capabilities.It adeptly addresses challenges such as mass reduction,intricate component fa...3D printing stands at the forefront of transforming space exploration,offering unprecedented on-demand and rapid manufacturing capabilities.It adeptly addresses challenges such as mass reduction,intricate component fabrication,and resource constraints.Despite the obstacles posed by microgravity and extreme environments,continual advancements underscore the pivotal role of 3D printing in aerospace science.Beyond its primary function of producing space structures,3D printing contributes significantly to progress in electronics,biomedicine,and resource optimization.This perspective delves into the technological advantages,environmental challenges,development status,and opportunities of 3D printing in space.Envisioning its crucial impact,we anticipate that 3D printing will unlock innovative solutions,reshape manufacturing practices,and foster self-sufficiency in future space endeavors.展开更多
In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order t...In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order to prove the main results,we first give some bidirectional estimates for several typical integrals.展开更多
目的:探究高分辨率血管壁成像时利用可变翻转角实现最优化采集的3D快速自旋回波序列(3D-SPACE)T1压脂与非压脂序列对大脑中动脉(middle cerebral artery,MCA)狭窄病人图像信号、血管壁及斑块情况的影响。方法:选取2021年1月—2022年12...目的:探究高分辨率血管壁成像时利用可变翻转角实现最优化采集的3D快速自旋回波序列(3D-SPACE)T1压脂与非压脂序列对大脑中动脉(middle cerebral artery,MCA)狭窄病人图像信号、血管壁及斑块情况的影响。方法:选取2021年1月—2022年12月于滨州市中心医院接受颅内磁共振血管成像(MR angiography,MRA)检查并确诊的MCA狭窄患者72例为研究对象,患者均接受MCA MRI检查,然后再分别用3D SPACE T1压脂与非压脂序列测量,分析图像信号差异情况,对比不同序列测量的血管断面、管腔及斑块面积情况及图像质量主观评价;分析不同医师图像质量评分的一致性情况。结果:72例患者中,不同序列测量均可以清晰地将MCA斑块显示出来,但测量出的信号存在明显的差异。不同序列测量血管断面、管腔面积对比差异不显著(P>0.05);3D SPACE T1非压脂序列测量斑块面积大于压脂序列测量面积(P<0.05);2种序列管腔显示情况对比差异无统计学意义(P>0.05),其他图像质量对比差异有统计学意义(P<0.05)。2名医生图像质量评分具有良好的一致性。结论:高分辨率血管壁成像时3D SPACE T1非压脂序更有助于对MCA狭窄病人图像信号、血管壁及斑块的测量,可为临床提供治疗依据。展开更多
文摘目的:对比三维多回波恢复梯度回波(3D MERGE)、三维可变反转角快速自旋回波(3D SPACE STIR)序列在腰椎间盘突出症(LDH)检查中的应用效果。方法:选择2020年1月~2022年11月收治的135例LDH患者,回顾性分析患者临床和磁共振成像(MRI)资料,所有患者均接受常规MRI扫描及3D MERGE、3D SPACE STIR序列扫描,对比3D MERGE、3D SPACE STIR序列测量神经根直径的一致性,评价两种序列的图像质量参数[信噪比(SNR)、对比噪声比(CNR)]、图像清晰度评分。结果:3D MERGE和3D SPACE STIR序列测量的L3~S1神经根直径比较差异无统计学意义(P>0.05),且两组序列测量的L3、L4、L5和S1直径均显示出较高相关性(r=0.957,0.986,0.975,0.972,P<0.05);3D MERGE序列的SNR及CNR均高于3D SPACE STIR序列,神经根显示分级、图像清晰度评分优于3D SPACE STIR序列,差异有统计学意义(P<0.05)。结论:3D MERGE、3D SPACE STIR序列在LDH神经根直径测量中具有极高一致性,3D MERGE序列较3D SPACE STIR序列能够更清晰显示神经跟的解剖形态,图像质量更好。
基金supported by the National Natural Science Foundation of China(52125501 and 52205317)the Key Research Project of Shaanxi Province(2021LLRH-08)+4 种基金the Program for Innovation Team of Shaanxi Province(2023-CX-TD-17)the Natural Science Basis Research Plan in Shaanxi Province of China(2022JQ-523)the High-Level Talent Recruitment Program of Shaanxi Provincethe Fundamental Research Funds for the Central UniversitiesChina Postdoctoral Science Foundation。
文摘3D printing stands at the forefront of transforming space exploration,offering unprecedented on-demand and rapid manufacturing capabilities.It adeptly addresses challenges such as mass reduction,intricate component fabrication,and resource constraints.Despite the obstacles posed by microgravity and extreme environments,continual advancements underscore the pivotal role of 3D printing in aerospace science.Beyond its primary function of producing space structures,3D printing contributes significantly to progress in electronics,biomedicine,and resource optimization.This perspective delves into the technological advantages,environmental challenges,development status,and opportunities of 3D printing in space.Envisioning its crucial impact,we anticipate that 3D printing will unlock innovative solutions,reshape manufacturing practices,and foster self-sufficiency in future space endeavors.
基金supported by the Natural Science Foundation of Hunan Province of China(2022JJ30369)the Education Department Important Foundation of Hunan Province in China(23A0095)。
文摘In this paper,we investigate sufficient and necessary conditions such that generalized Forelli-Rudin type operators T_(λ,τ,k),S_(λ,τ,k),Q_(λ,τ,k)and R_(λ,τ,k)are bounded between Lebesgue type spaces.In order to prove the main results,we first give some bidirectional estimates for several typical integrals.
文摘目的:探究高分辨率血管壁成像时利用可变翻转角实现最优化采集的3D快速自旋回波序列(3D-SPACE)T1压脂与非压脂序列对大脑中动脉(middle cerebral artery,MCA)狭窄病人图像信号、血管壁及斑块情况的影响。方法:选取2021年1月—2022年12月于滨州市中心医院接受颅内磁共振血管成像(MR angiography,MRA)检查并确诊的MCA狭窄患者72例为研究对象,患者均接受MCA MRI检查,然后再分别用3D SPACE T1压脂与非压脂序列测量,分析图像信号差异情况,对比不同序列测量的血管断面、管腔及斑块面积情况及图像质量主观评价;分析不同医师图像质量评分的一致性情况。结果:72例患者中,不同序列测量均可以清晰地将MCA斑块显示出来,但测量出的信号存在明显的差异。不同序列测量血管断面、管腔面积对比差异不显著(P>0.05);3D SPACE T1非压脂序列测量斑块面积大于压脂序列测量面积(P<0.05);2种序列管腔显示情况对比差异无统计学意义(P>0.05),其他图像质量对比差异有统计学意义(P<0.05)。2名医生图像质量评分具有良好的一致性。结论:高分辨率血管壁成像时3D SPACE T1非压脂序更有助于对MCA狭窄病人图像信号、血管壁及斑块的测量,可为临床提供治疗依据。
