为研究声脉冲辐射力超声技术(acoustic radiation force impulse,ARFI)无创定量评价肝纤维化的应用价值。应用ARFI技术定量检测158例部分乙肝患者和志愿者的肝实质剪切波速度,同时所有的慢性乙肝患者均在ARFI检查后随访穿刺活检病理学...为研究声脉冲辐射力超声技术(acoustic radiation force impulse,ARFI)无创定量评价肝纤维化的应用价值。应用ARFI技术定量检测158例部分乙肝患者和志愿者的肝实质剪切波速度,同时所有的慢性乙肝患者均在ARFI检查后随访穿刺活检病理学检查结果。结果显示,研究显示S0与S1期的弹性参数没有明显的差异,但对于评价S2级以上程度的肝纤维化,ARFI技术均有较高的准确性,特别是对S4期肝纤维化,ROC曲线下面积达0.942,且超声弹性成像评分与肝纤维化病理学分期之间呈正相关(r=0.875,P=0.000)。由此可知,应用ARFI技术检测各期慢性乙肝肝纤维化横向剪切波速的佳截断值可能成为诊断肝纤维化各分期的重要依据。展开更多
We report on the development of an electrical characterization admittance spectroscopy equipment and method based on an off-the-shelf lock-in detector that is cheap and yet highly sensitive. It is concluded that a con...We report on the development of an electrical characterization admittance spectroscopy equipment and method based on an off-the-shelf lock-in detector that is cheap and yet highly sensitive. It is concluded that a contacted constant-pressure electrode configuration is preferable. It was further determined that the temperature does not have great impact in the measured values, but relative humidity of air can be important, especially in the constant-gap electrode configuration. In-situ measurements are difficult since the coupling of the plant with the environment is of high importance. Another aspect is the cables;they are important in that they have to be terminated by their characteristic impedance (50 Ω?in our case) to avoid reflections that introduce artificial attenuation and phase shifts in the signal. We introduce a fingerprint plot type to be able to distinguish between various plants and other specimens, and can actually detect the aqueous state of a plant.展开更多
文摘为研究声脉冲辐射力超声技术(acoustic radiation force impulse,ARFI)无创定量评价肝纤维化的应用价值。应用ARFI技术定量检测158例部分乙肝患者和志愿者的肝实质剪切波速度,同时所有的慢性乙肝患者均在ARFI检查后随访穿刺活检病理学检查结果。结果显示,研究显示S0与S1期的弹性参数没有明显的差异,但对于评价S2级以上程度的肝纤维化,ARFI技术均有较高的准确性,特别是对S4期肝纤维化,ROC曲线下面积达0.942,且超声弹性成像评分与肝纤维化病理学分期之间呈正相关(r=0.875,P=0.000)。由此可知,应用ARFI技术检测各期慢性乙肝肝纤维化横向剪切波速的佳截断值可能成为诊断肝纤维化各分期的重要依据。
文摘We report on the development of an electrical characterization admittance spectroscopy equipment and method based on an off-the-shelf lock-in detector that is cheap and yet highly sensitive. It is concluded that a contacted constant-pressure electrode configuration is preferable. It was further determined that the temperature does not have great impact in the measured values, but relative humidity of air can be important, especially in the constant-gap electrode configuration. In-situ measurements are difficult since the coupling of the plant with the environment is of high importance. Another aspect is the cables;they are important in that they have to be terminated by their characteristic impedance (50 Ω?in our case) to avoid reflections that introduce artificial attenuation and phase shifts in the signal. We introduce a fingerprint plot type to be able to distinguish between various plants and other specimens, and can actually detect the aqueous state of a plant.
