Objective： In the present study, spinal metastatic tumors, brucellar spondylitis and spinal tuberculosis werequantitatively analyzed using dynamic contrast-enhanced magnetic resonance imaging （DCE-MRI） to assess th...Objective： In the present study, spinal metastatic tumors, brucellar spondylitis and spinal tuberculosis werequantitatively analyzed using dynamic contrast-enhanced magnetic resonance imaging （DCE-MRI） to assess thevalue of DCE-MRI in the differential diagnosis of these diseases.Methods： Patients with brucellar spondylitis, spinal tuberculosis or a spinal metastatic tumor （30 cases of each）received conventional MRI and DCE-MRI examination. The volume transfer constant （Ktrans）, rate constant （Kep）,extravascular extracellular volume fraction （Ve） and plasma volume fraction （Vp） of the diseased vertebral bodieswere measured on the perfusion parameter map, and the differences in these parameters between the patients werecompared.Results： For pathological vertebrae in cases of spinal metastatic tumor, brucellar spondylitis and spinaltuberculosis, respectively, the Ktrans values （median ＋ quartile pitch） were 0.989±0.014, 0.720±0.011 and0.317±0.005 min-1; the Kep values were 2.898±0.055, 1.327±0.017 and 0.748±0.006 min-1; the Ve values were0.339±0.008, 0.542±0.013 and 0.428±0.018; the Vp values were 0.048±0.008, 0.035±0.004 and 0.028±0.009; thecorresponding H values were 50.25 （for Ktrans）, 52.47 （for Kep）, 48.33 （for Ve） and 46.56 （for Vp）, and all differenceswere statistically significant （two-sided P〈0.05）.Conclusions： The quantitative analysis of DCE-MRI has a certain value in the differential diagnosis of spinalmetastatic tumor, brucellar spondylitis and spinal tuberculosis.展开更多
Strategical elements,such as rare earth elements,play a crucial role in the industry,especially in producing high-tech materials.Major global industries have developed a strong dependence on rare earth materials.Every...Strategical elements,such as rare earth elements,play a crucial role in the industry,especially in producing high-tech materials.Major global industries have developed a strong dependence on rare earth materials.Every year,there are innovations in industries such as modern technology,green energy,or communications technology,which need more strategic metals to improve investment profitability.This article reviews advances in rare earth separation methods and techniques to guide and recommend the best extractants,depending on leaching conditions and the final target product.Each method for separating and extracting agents is individually revised in terms of the mechanism and interaction of providing rare earth elements.This paper also evaluates past and current trends of these methods and technical extractants and identifies their strengths and weaknesses.展开更多
基金funded by the National Natural Science Foundation of China (No. 81460259)
文摘Objective： In the present study, spinal metastatic tumors, brucellar spondylitis and spinal tuberculosis werequantitatively analyzed using dynamic contrast-enhanced magnetic resonance imaging （DCE-MRI） to assess thevalue of DCE-MRI in the differential diagnosis of these diseases.Methods： Patients with brucellar spondylitis, spinal tuberculosis or a spinal metastatic tumor （30 cases of each）received conventional MRI and DCE-MRI examination. The volume transfer constant （Ktrans）, rate constant （Kep）,extravascular extracellular volume fraction （Ve） and plasma volume fraction （Vp） of the diseased vertebral bodieswere measured on the perfusion parameter map, and the differences in these parameters between the patients werecompared.Results： For pathological vertebrae in cases of spinal metastatic tumor, brucellar spondylitis and spinaltuberculosis, respectively, the Ktrans values （median ＋ quartile pitch） were 0.989±0.014, 0.720±0.011 and0.317±0.005 min-1; the Kep values were 2.898±0.055, 1.327±0.017 and 0.748±0.006 min-1; the Ve values were0.339±0.008, 0.542±0.013 and 0.428±0.018; the Vp values were 0.048±0.008, 0.035±0.004 and 0.028±0.009; thecorresponding H values were 50.25 （for Ktrans）, 52.47 （for Kep）, 48.33 （for Ve） and 46.56 （for Vp）, and all differenceswere statistically significant （two-sided P〈0.05）.Conclusions： The quantitative analysis of DCE-MRI has a certain value in the differential diagnosis of spinalmetastatic tumor, brucellar spondylitis and spinal tuberculosis.
基金Project supported by Fundamental Research Funds for the Central Universities of China(FRF-BR-20-03B)the National Key R&D Program of China(2017YFF0106006)。
文摘Strategical elements,such as rare earth elements,play a crucial role in the industry,especially in producing high-tech materials.Major global industries have developed a strong dependence on rare earth materials.Every year,there are innovations in industries such as modern technology,green energy,or communications technology,which need more strategic metals to improve investment profitability.This article reviews advances in rare earth separation methods and techniques to guide and recommend the best extractants,depending on leaching conditions and the final target product.Each method for separating and extracting agents is individually revised in terms of the mechanism and interaction of providing rare earth elements.This paper also evaluates past and current trends of these methods and technical extractants and identifies their strengths and weaknesses.
