BACKGROUND:Contrast agents help to improve visibility in magnetic resonance(MR)imaging.However,owing to the large interstitial spaces of the liver,there is a reduction in the natural contrast gradient between lesions ...BACKGROUND:Contrast agents help to improve visibility in magnetic resonance(MR)imaging.However,owing to the large interstitial spaces of the liver,there is a reduction in the natural contrast gradient between lesions and healthy tissue.This study was undertaken to evaluate the efficacy and safety of the liverspecific MR imaging contrast agent gadoxetate disodium(GdEOB-DTPA)in Chinese patients.METHODS:This was a single-arm,open-label,multicenter study in patients with known or suspected focal liver lesions referred for contrast-enhanced MR imaging.MR imaging was performed in 234 patients before and after a single intravenous bolus of Gd-EOB-DTPA(0.025 mmol/kg body weight).Images were evaluated by clinical study investigators and three independent,blinded radiologists.The primary efficacy endpoint was sensitivity in lesion detection.RESULTS:Gd-EOB-DTPA improved sensitivity in lesion detection by 9.46%compared with pre-contrast imaging for the average of the three blinded readers(94.78%vs 85.32%for Gd-EOB-DTPA vs pre-contrast,respectively).Improvements in detection were more pronounced in lesions less than 1cm.Gd-EOB-DTPA improved diagnostic accuracy in lesion classification.CONCLUSIONS:This open-label study demonstrated that Gd-EOB-DTPA improves diagnostic sensitivity in liver lesions,particularly in those smaller than 1 cm.Gd-EOB-DTPA also significantly improves the diagnostic accuracy in lesion classification,and furthermore,Gd-EOB-DTPA is safe in Chinese patients with liver lesions.展开更多
Objective： To assess if arachnoid cells have the capability to present antigen and activate T-lymphocytes after stimulation by bloody cerebrospinal fluid （CSF）, and to illuminate the mechanism of coagulation-initia...Objective： To assess if arachnoid cells have the capability to present antigen and activate T-lymphocytes after stimulation by bloody cerebrospinal fluid （CSF）, and to illuminate the mechanism of coagulation-initiated inflammation in the subarachnoid space after subarachnoid hemorrhage （SAH）. Methods： Arachnoid cells were cultured, characterized, and examined by immunofluorescence for the basal expression of human leukocyte antigen-DR （HLA-DR）, Expression of HLA-DR, after co-culturing arachnoid cells in vitro with bloody CSF, was investigated by immunofluorescence and flow cytometry （FCM）. The variation of arachnoid cells＇ ultrastructure was observed by transmission electron microscope （TEM）. Arachnoid cells were co-cultured with peripheral blood mononuclear cells （PBMCs）. The content of soluble interleukin-2 receptor （slL-2r） in culture medium was detected by enzyme-linked immunosorbent assay （ELISA）. Results： （1） Arachnoid cells were successfully cultured for many passages. The immunofluorescent staining was positive for HLA-DR in over 95% of the human arachnoid cells. The punctate HI_A-DR was distributed in cytoplasm and not in the karyon. （2） After co-culturing arachnoid cells in vitro with bloody CSF, numerous particles with strong fluorescence appeared in the cytoplasm on Day 6. On Day 8, the quantity of particles and fluorescent intensity were maximal. FCM showed that the percentage of HLA-DR expressing cells was （2.5＋_0.4）% at the first 5 d, increasing to （60.8＋_3.6）% on Day 7. （3） After co-culturing arachnoid cells in vitro with bloody CSF, many lysosome and secondary lysosome particles were present in the cytoplasm. Hyperplasia of rough endoplasmic re- ticulum and enlarged cysts were observed, with numerous phagocytizing vesicles also observed at the edge of the arachnoid cells. （4） Arachnoid cells stimulated by bloody CSF were co-cultured in vitro with PBMCs. The content of slL-2r in the culture medium, having been maintained at around 1.30 ng/ml during the first 3 d, had increased by Day 4. The content of slL-2r peaked 7.53 ng/ml on Day 7 and then reduced gradually. Conclusions： （1） Basic HLA-DR expression is present in arachnoid cells. （2） After stimulation by bloody CSF, arachnoid cells have the potential to serve as antigen presenting cells （APCs） and the ability to activate T-lymphocytes, indicating that arachnoid cells are involved in the mechanism of coagulation-initiated inflammation in the subarachnoid space after SAH.展开更多
BACKGROUND: Pyogenic hepatic abscess may mimic primary or secondary carcinoma of the liver on contrast-enhanced computed tomography(CECT). The present study was to explore the usefulness of the analysis of multislice-...BACKGROUND: Pyogenic hepatic abscess may mimic primary or secondary carcinoma of the liver on contrast-enhanced computed tomography(CECT). The present study was to explore the usefulness of the analysis of multislice-based texture acquired from CECT in the differentiation between pyogenic hepatic abscesses and malignant mimickers.METHODS: This retrospective study included 25 abscesses in 20 patients and 33 tumors in 26 subjects who underwent CECT. To make comparison, we also enrolled 19 patients with hepatic single simple cyst. The images from CECT were analyzed using a Laplacian of Gaussian band-pass filter(5 filter levels with sigma weighting ranging from 1.0 to 2.5). We also quantified the uniformity, entropy, kurtosis and skewness of the multislice-based texture at different sigma weightings. Statistical significance for these parameters was tested with oneway ANOVA followed by Tukey honestly significant difference(HSD) test. Diagnostic performance was evaluated using the receiver operating characteristic(ROC) curve analysis.RESULTS: There were significant differences in entropy and uniformity at all sigma weightings(P〈0.001) among hepatic abscesses, malignant mimickers and simple cysts. The significant difference in kurtosis and skewness was shown at sigma 1.8 and 2.0 weightings(P=0.002-0.006). Tukey HSD testshowed that the abscesses had a significantly higher entropy and lower uniformity compared with malignant mimickers(P=0.000-0.004). Entropy(at a sigma 2.0 weighting) had the largest area under the ROC curve(0.888) in differentiating abscesses from malignant mimickers, with a sensitivity of 81.8% and a specificity of 88.0% when the cutoff value was set to 3.64.CONCLUSION: Multislice-based texture analysis may be useful for differentiating pyogenic hepatic abscesses from malignant mimickers.展开更多
The high-strain-rate mechanical response of Mg alloy/SiC_p composite foams has received increased attention in recent years due to their light weight and potential to absorb large amounts of energy during deformation....The high-strain-rate mechanical response of Mg alloy/SiC_p composite foams has received increased attention in recent years due to their light weight and potential to absorb large amounts of energy during deformation. Dynamic compressive properties of closed-cell Mg alloy/SiC_p composite foams with diff erent relative densities(0.162, 0.227 and 0.351) and diff erent SiC_p additions(0, 4 and 8 wt%) have been investigated using Split-Hopkinson pressure bar. It is shown that peak stress and energy absorption capacity signifi cantly increase as the relative density increases at the range of testing strain rates. Peak stress and energy absorption display strain rate dependence. The peak stress of specimens with 0 wt% and 4 wt% SiC particles additions grows with increasing strain rate. Meanwhile, the increment in the peak stress of specimens with 8 wt% addition is not signifi cant with strain rate increasing. The increase in strain rate increases the energy absorption capacity. The suitable amount of SiC particles addition has great advantages over increasing the peak stress and energy absorption capacity at the high strain rate. The strain-rate-sensitive matrix, cell morphology, morphological defects and gas pressure have an impact on the strain-rate sensitivity of Mg alloy/SiC_p composite foams.展开更多
The unloading relaxation caused by excavation for construction of high arch dams is an important factor influencing the foundation’s integrity and strength.To evaluate the degree of unloading relaxation,the long-shor...The unloading relaxation caused by excavation for construction of high arch dams is an important factor influencing the foundation’s integrity and strength.To evaluate the degree of unloading relaxation,the long-short term memory(LSTM)network was used to estimate the depth of unloading relaxation zones on the left bank foundation of the Baihetan Arch Dam.Principal component analysis indicates that rock charac-teristics,the structural plane,the protection layer,lithology,and time are the main factors.The LSTM network results demonstrate the unloading relaxation characteristics of the left bank,and the relationships with the factors were also analyzed.The structural plane has the most significant influence on the distribution of unloading relaxation zones.Compared with massive basalt,the columnar jointed basalt experiences a more significant unloading relaxation phenomenon with a clear time effect,with the average unloading relaxation period being 50 d.The protection layer can effectively reduce the unloading relaxation depth by approximately 20%.展开更多
In the present work,a 3-D aerator device with backward lateral deflectors,called BLD-3-D aerator device,is developed,and the lateral cavity and fin performance of the BLD-3-D aerator device are experimentally investig...In the present work,a 3-D aerator device with backward lateral deflectors,called BLD-3-D aerator device,is developed,and the lateral cavity and fin performance of the BLD-3-D aerator device are experimentally investigated.The findings show that,the relative lateral cavity length with backward lateral deflectors is shorter than that with current lateral deflectors under the same approach flow conditions,and on the basis of the results of the relative cavity length ratio between the lateral and bottom aerators the BLD-3-D aerator device is of remarkable performance for the water fin control thanks to the decrease of the relative lateral cavity length.展开更多
To the Editor:Coronary computed tomographic angiography(CCTA)has been considered as one of the most important noninvasive imaging modalities in diagnosing coronary artery disease(CAD).[1]Modern scanner of CCTA can pro...To the Editor:Coronary computed tomographic angiography(CCTA)has been considered as one of the most important noninvasive imaging modalities in diagnosing coronary artery disease(CAD).[1]Modern scanner of CCTA can provide precise coronary atherosclerotic plaque information,showing improved diagnostic accuracy and sensitivity for identifying obstructive CAD with a preferable temporal and spatial resolution.Several studies have demonstrated the prognosis value of CCTA for the prediction of future adverse CAD events.展开更多
基金supported by a grant from Bayer HealthCare/Bayer Schering Pharma AG
文摘BACKGROUND:Contrast agents help to improve visibility in magnetic resonance(MR)imaging.However,owing to the large interstitial spaces of the liver,there is a reduction in the natural contrast gradient between lesions and healthy tissue.This study was undertaken to evaluate the efficacy and safety of the liverspecific MR imaging contrast agent gadoxetate disodium(GdEOB-DTPA)in Chinese patients.METHODS:This was a single-arm,open-label,multicenter study in patients with known or suspected focal liver lesions referred for contrast-enhanced MR imaging.MR imaging was performed in 234 patients before and after a single intravenous bolus of Gd-EOB-DTPA(0.025 mmol/kg body weight).Images were evaluated by clinical study investigators and three independent,blinded radiologists.The primary efficacy endpoint was sensitivity in lesion detection.RESULTS:Gd-EOB-DTPA improved sensitivity in lesion detection by 9.46%compared with pre-contrast imaging for the average of the three blinded readers(94.78%vs 85.32%for Gd-EOB-DTPA vs pre-contrast,respectively).Improvements in detection were more pronounced in lesions less than 1cm.Gd-EOB-DTPA improved diagnostic accuracy in lesion classification.CONCLUSIONS:This open-label study demonstrated that Gd-EOB-DTPA improves diagnostic sensitivity in liver lesions,particularly in those smaller than 1 cm.Gd-EOB-DTPA also significantly improves the diagnostic accuracy in lesion classification,and furthermore,Gd-EOB-DTPA is safe in Chinese patients with liver lesions.
基金Project supported by the National Natural Science Foundation of China (No. 30370497)the Science and Technology Research Program of Zhejiang Province,China (No. 2007-C-33039)
文摘Objective： To assess if arachnoid cells have the capability to present antigen and activate T-lymphocytes after stimulation by bloody cerebrospinal fluid （CSF）, and to illuminate the mechanism of coagulation-initiated inflammation in the subarachnoid space after subarachnoid hemorrhage （SAH）. Methods： Arachnoid cells were cultured, characterized, and examined by immunofluorescence for the basal expression of human leukocyte antigen-DR （HLA-DR）, Expression of HLA-DR, after co-culturing arachnoid cells in vitro with bloody CSF, was investigated by immunofluorescence and flow cytometry （FCM）. The variation of arachnoid cells＇ ultrastructure was observed by transmission electron microscope （TEM）. Arachnoid cells were co-cultured with peripheral blood mononuclear cells （PBMCs）. The content of soluble interleukin-2 receptor （slL-2r） in culture medium was detected by enzyme-linked immunosorbent assay （ELISA）. Results： （1） Arachnoid cells were successfully cultured for many passages. The immunofluorescent staining was positive for HLA-DR in over 95% of the human arachnoid cells. The punctate HI_A-DR was distributed in cytoplasm and not in the karyon. （2） After co-culturing arachnoid cells in vitro with bloody CSF, numerous particles with strong fluorescence appeared in the cytoplasm on Day 6. On Day 8, the quantity of particles and fluorescent intensity were maximal. FCM showed that the percentage of HLA-DR expressing cells was （2.5＋_0.4）% at the first 5 d, increasing to （60.8＋_3.6）% on Day 7. （3） After co-culturing arachnoid cells in vitro with bloody CSF, many lysosome and secondary lysosome particles were present in the cytoplasm. Hyperplasia of rough endoplasmic re- ticulum and enlarged cysts were observed, with numerous phagocytizing vesicles also observed at the edge of the arachnoid cells. （4） Arachnoid cells stimulated by bloody CSF were co-cultured in vitro with PBMCs. The content of slL-2r in the culture medium, having been maintained at around 1.30 ng/ml during the first 3 d, had increased by Day 4. The content of slL-2r peaked 7.53 ng/ml on Day 7 and then reduced gradually. Conclusions： （1） Basic HLA-DR expression is present in arachnoid cells. （2） After stimulation by bloody CSF, arachnoid cells have the potential to serve as antigen presenting cells （APCs） and the ability to activate T-lymphocytes, indicating that arachnoid cells are involved in the mechanism of coagulation-initiated inflammation in the subarachnoid space after SAH.
基金supported by grants from Medical Engineering Cross Research Foundation of Shanghai Jiaotong University(YG2013MS37 and YG2012MS16)the National Natural Science Foundation of China(81201172,81371660 and 81371622)
文摘BACKGROUND: Pyogenic hepatic abscess may mimic primary or secondary carcinoma of the liver on contrast-enhanced computed tomography(CECT). The present study was to explore the usefulness of the analysis of multislice-based texture acquired from CECT in the differentiation between pyogenic hepatic abscesses and malignant mimickers.METHODS: This retrospective study included 25 abscesses in 20 patients and 33 tumors in 26 subjects who underwent CECT. To make comparison, we also enrolled 19 patients with hepatic single simple cyst. The images from CECT were analyzed using a Laplacian of Gaussian band-pass filter(5 filter levels with sigma weighting ranging from 1.0 to 2.5). We also quantified the uniformity, entropy, kurtosis and skewness of the multislice-based texture at different sigma weightings. Statistical significance for these parameters was tested with oneway ANOVA followed by Tukey honestly significant difference(HSD) test. Diagnostic performance was evaluated using the receiver operating characteristic(ROC) curve analysis.RESULTS: There were significant differences in entropy and uniformity at all sigma weightings(P〈0.001) among hepatic abscesses, malignant mimickers and simple cysts. The significant difference in kurtosis and skewness was shown at sigma 1.8 and 2.0 weightings(P=0.002-0.006). Tukey HSD testshowed that the abscesses had a significantly higher entropy and lower uniformity compared with malignant mimickers(P=0.000-0.004). Entropy(at a sigma 2.0 weighting) had the largest area under the ROC curve(0.888) in differentiating abscesses from malignant mimickers, with a sensitivity of 81.8% and a specificity of 88.0% when the cutoff value was set to 3.64.CONCLUSION: Multislice-based texture analysis may be useful for differentiating pyogenic hepatic abscesses from malignant mimickers.
基金financially supported by National Natural Science Foundation of China (Nos. 51874093, 51174060 and 51301109)Fundamental Research Funds for the Central Universities (No. N162410002-2-10)
文摘The high-strain-rate mechanical response of Mg alloy/SiC_p composite foams has received increased attention in recent years due to their light weight and potential to absorb large amounts of energy during deformation. Dynamic compressive properties of closed-cell Mg alloy/SiC_p composite foams with diff erent relative densities(0.162, 0.227 and 0.351) and diff erent SiC_p additions(0, 4 and 8 wt%) have been investigated using Split-Hopkinson pressure bar. It is shown that peak stress and energy absorption capacity signifi cantly increase as the relative density increases at the range of testing strain rates. Peak stress and energy absorption display strain rate dependence. The peak stress of specimens with 0 wt% and 4 wt% SiC particles additions grows with increasing strain rate. Meanwhile, the increment in the peak stress of specimens with 8 wt% addition is not signifi cant with strain rate increasing. The increase in strain rate increases the energy absorption capacity. The suitable amount of SiC particles addition has great advantages over increasing the peak stress and energy absorption capacity at the high strain rate. The strain-rate-sensitive matrix, cell morphology, morphological defects and gas pressure have an impact on the strain-rate sensitivity of Mg alloy/SiC_p composite foams.
基金This work was supported by the National Key Research and Development Program of China(Grant No.2018YFC0407004)the Natural Science Foundation of China(Grants No.51939004 and 11772116).
文摘The unloading relaxation caused by excavation for construction of high arch dams is an important factor influencing the foundation’s integrity and strength.To evaluate the degree of unloading relaxation,the long-short term memory(LSTM)network was used to estimate the depth of unloading relaxation zones on the left bank foundation of the Baihetan Arch Dam.Principal component analysis indicates that rock charac-teristics,the structural plane,the protection layer,lithology,and time are the main factors.The LSTM network results demonstrate the unloading relaxation characteristics of the left bank,and the relationships with the factors were also analyzed.The structural plane has the most significant influence on the distribution of unloading relaxation zones.Compared with massive basalt,the columnar jointed basalt experiences a more significant unloading relaxation phenomenon with a clear time effect,with the average unloading relaxation period being 50 d.The protection layer can effectively reduce the unloading relaxation depth by approximately 20%.
基金Project supported by the National Natural Science Foundation of China(Grant No.50879021).
文摘In the present work,a 3-D aerator device with backward lateral deflectors,called BLD-3-D aerator device,is developed,and the lateral cavity and fin performance of the BLD-3-D aerator device are experimentally investigated.The findings show that,the relative lateral cavity length with backward lateral deflectors is shorter than that with current lateral deflectors under the same approach flow conditions,and on the basis of the results of the relative cavity length ratio between the lateral and bottom aerators the BLD-3-D aerator device is of remarkable performance for the water fin control thanks to the decrease of the relative lateral cavity length.
基金National Key Research and Development Program of China(No.2016YFC1300304)Beijing NOVA Program(No.Z181100006218055)。
文摘To the Editor:Coronary computed tomographic angiography(CCTA)has been considered as one of the most important noninvasive imaging modalities in diagnosing coronary artery disease(CAD).[1]Modern scanner of CCTA can provide precise coronary atherosclerotic plaque information,showing improved diagnostic accuracy and sensitivity for identifying obstructive CAD with a preferable temporal and spatial resolution.Several studies have demonstrated the prognosis value of CCTA for the prediction of future adverse CAD events.
