应用求解算子方程的Ulm方法构造了求解一类矩阵特征值反问题(IEP)的新算法.所给算法避免了文献[Aishima K.,A quadratically convergent algorithm based on matrix equations for inverse eigenvalue problems,Linear Algebra and its ...应用求解算子方程的Ulm方法构造了求解一类矩阵特征值反问题(IEP)的新算法.所给算法避免了文献[Aishima K.,A quadratically convergent algorithm based on matrix equations for inverse eigenvalue problems,Linear Algebra and its Applications,2018,542:310-333]中算法在每次迭代中要求解一个线性方程组的不足,证明了在给定谱数据互不相同的条件下所给算法具有根收敛意义下的二次收敛性.数值实验表明本文所给算法在矩阵阶数较大时计算效果优于上文所给算法.展开更多
BACKGROUND The main endemic areas of alveolar echinococcosis(AE)are in Central Europe and Western China.Both the infiltration of intrahepatic vascular and bile duct structures as well as extrahepatic disease can lead ...BACKGROUND The main endemic areas of alveolar echinococcosis(AE)are in Central Europe and Western China.Both the infiltration of intrahepatic vascular and bile duct structures as well as extrahepatic disease can lead to further complications and may increase morbidity in patients with AE.AIM To evaluate vascular/biliary involvement in hepatic AE and its distant extrahepatic disease manifestations in an international collective was the aim.METHODS Consecutively,five experienced examiners evaluated contrast-enhanced abdominal computed tomography(CT)scans for 200 patients with hepatic AE of each of four locations(n=50)in Germany,France and China.Therefore,we retrospectively included the 50 most recent abdominal contrast-enhanced CT examinations at each center,performed because of hepatic AE from September 21,2007 to March 21,2018.AE liver lesions were classified according to the echinococcosis multilocularis Ulm classification for CT(EMUC-CT).Distant extrahepatic manifestations were documented either by whole body positron emission tomography–CT or with the addition of thoracic CT and cranial magnetic resonance imaging.Vascular/biliary involvement of the hepatic disease as well as the presence of distant extrahepatic manifestations were correlated with the EMUC-CT types of liver lesion.Statistical analysis was performed using SAS Version 9.4(SAS Institute Inc.,Cary,NC,United States).RESULTS Distant extrahepatic AE manifestations were significantly more frequent in China than in Europe(P=0.0091).A significant relationship was found between the presence of distant extrahepatic disease and AE liver lesion size(P=0.0075).Vascular/biliary structures were involved by the liver lesions significantly more frequently in China than in Europe(P<0.0001),and vascular/biliary involvement depended on lesion size.Different morphological types of AE liver lesions led to varying frequencies of vascular/biliary involvement and were associated with different frequencies of distant extrahepatic manifestations:Vascular/biliary involvement as a function of lesions primary morphology ranged from 5.88%of type IV liver lesions to 100%among type III lesions.Type IV differed significantly in these associations from types I,II,and III(P<0.0001).With respect to extrahepatic disease,the primary morphology types IV and V of liver lesions were not associated with any case of distant extrahepatic disease.In contrast,distant extrahepatic manifestations in types I–III were found to varying degrees,with a maximum of 22%for type III.CONCLUSION Different CT morphological patterns of hepatic AE lesions influence vascular/biliary involvement and the occurrence of distant extrahepatic manifestations.There are intercontinental differences regarding the characteristics of AE manifestation.展开更多
文摘应用求解算子方程的Ulm方法构造了求解一类矩阵特征值反问题(IEP)的新算法.所给算法避免了文献[Aishima K.,A quadratically convergent algorithm based on matrix equations for inverse eigenvalue problems,Linear Algebra and its Applications,2018,542:310-333]中算法在每次迭代中要求解一个线性方程组的不足,证明了在给定谱数据互不相同的条件下所给算法具有根收敛意义下的二次收敛性.数值实验表明本文所给算法在矩阵阶数较大时计算效果优于上文所给算法.
基金Supported by a German Research Foundation funded project called“Establishment of a national database for alveolar echinococcosis”,No.KA 4356/3-1“Implementation of interfaces for the standardization of nationaldatabase systems for alveolar echinococcosis and its transformation processes”,No.KR 5204/1-2+1 种基金Multiple imaging study of the Hepatic Alveolar Echinococcosis after albendazole treatment,the Qinghai Science and Technology Department,No.2017-SF-158and the Müller Holding Ltd.and Co.KG Ulm.
文摘BACKGROUND The main endemic areas of alveolar echinococcosis(AE)are in Central Europe and Western China.Both the infiltration of intrahepatic vascular and bile duct structures as well as extrahepatic disease can lead to further complications and may increase morbidity in patients with AE.AIM To evaluate vascular/biliary involvement in hepatic AE and its distant extrahepatic disease manifestations in an international collective was the aim.METHODS Consecutively,five experienced examiners evaluated contrast-enhanced abdominal computed tomography(CT)scans for 200 patients with hepatic AE of each of four locations(n=50)in Germany,France and China.Therefore,we retrospectively included the 50 most recent abdominal contrast-enhanced CT examinations at each center,performed because of hepatic AE from September 21,2007 to March 21,2018.AE liver lesions were classified according to the echinococcosis multilocularis Ulm classification for CT(EMUC-CT).Distant extrahepatic manifestations were documented either by whole body positron emission tomography–CT or with the addition of thoracic CT and cranial magnetic resonance imaging.Vascular/biliary involvement of the hepatic disease as well as the presence of distant extrahepatic manifestations were correlated with the EMUC-CT types of liver lesion.Statistical analysis was performed using SAS Version 9.4(SAS Institute Inc.,Cary,NC,United States).RESULTS Distant extrahepatic AE manifestations were significantly more frequent in China than in Europe(P=0.0091).A significant relationship was found between the presence of distant extrahepatic disease and AE liver lesion size(P=0.0075).Vascular/biliary structures were involved by the liver lesions significantly more frequently in China than in Europe(P<0.0001),and vascular/biliary involvement depended on lesion size.Different morphological types of AE liver lesions led to varying frequencies of vascular/biliary involvement and were associated with different frequencies of distant extrahepatic manifestations:Vascular/biliary involvement as a function of lesions primary morphology ranged from 5.88%of type IV liver lesions to 100%among type III lesions.Type IV differed significantly in these associations from types I,II,and III(P<0.0001).With respect to extrahepatic disease,the primary morphology types IV and V of liver lesions were not associated with any case of distant extrahepatic disease.In contrast,distant extrahepatic manifestations in types I–III were found to varying degrees,with a maximum of 22%for type III.CONCLUSION Different CT morphological patterns of hepatic AE lesions influence vascular/biliary involvement and the occurrence of distant extrahepatic manifestations.There are intercontinental differences regarding the characteristics of AE manifestation.
