There is continuing disparity between demand for and supply of kidneys for transplantation. This review describes the current state of kidney donation after cardiac death （DCD） and provides recommendations for a way...There is continuing disparity between demand for and supply of kidneys for transplantation. This review describes the current state of kidney donation after cardiac death （DCD） and provides recommendations for a way forward. The conversion rate for potential DCD donors varies from 40%-80%. Compared to con-trolled DCD, uncontrolled DCD is more labour intensive, has a lower conversion rate and a higher discard rate. The super-rapid laparotomy technique involving direct aortic cannulation is preferred over in situ perfusion in controlled DCD donation and is associated with lower kidney discard rates, shorter warm ischaemia times and higher graft survival rates. DCD kidneys showed a 5.73-fold increase in the incidence of delayed graft function （DGF） and a higher primary non function rate compared to donation after brain death kidneys, but the long term graft function is equivalent between the two. The cold ischaemia time is a controllable factor that signifcantly infuences the outcome of allografts, for example, limiting it to 〈 12 h markedly reduces DGF. DCD kidneys from donors 〈 50 function like stan-dard criteria kidneys and should be viewed as such. As the majority of DCD kidneys are from controlled dona-tion, incorporation of uncontrolled donation will expand the donor pool. Efforts to maximise the supply of kid-neys from DCD include： implementing organ recovery from emergency department setting; improving family consent rate; utilising technological developments to optimise organs either prior to recovery from donors or during storage; improving organ allocation to ensure best utility; and improving viability testing to reduce primary non function.展开更多
针对基于单系统单卫星GNSS-MR(GNSS Multipath Reflectometry)土壤湿度反演的可靠性不高、实际可操作性不强和最小二乘估计不具鲁棒性的缺点,为获取更优的延迟相位估值,并改善GNSS-MR土壤湿度反演的可靠性和实际可操作性,同时简化繁杂...针对基于单系统单卫星GNSS-MR(GNSS Multipath Reflectometry)土壤湿度反演的可靠性不高、实际可操作性不强和最小二乘估计不具鲁棒性的缺点,为获取更优的延迟相位估值,并改善GNSS-MR土壤湿度反演的可靠性和实际可操作性,同时简化繁杂的选星过程,提出了一种基于抗差估计的多系统多卫星组合GNSS-MR土壤湿度反演算法。该算法首先顾及多径环境的差异性、多径误差的周期特性等进行信噪比SNR(Signal to NoiseRatio)观测值的筛选,然后采用基于IGGⅢ(Weight Function Ⅲ Developed by Institute of Geodesy and Geophysics)权函数的抗差估计解求延迟相位,进而获得表征土壤湿度变化趋势的延迟相位组合。实验结果表明,相较于未采用抗差估计的多系统多卫星组合(方案1)和单卫星组合(方案3),得益于抗差估计良好的鲁棒性,基于抗差估计的多系统多卫星组合(方案2)和单卫星组合(方案4)获得了较高的建模精度,所得延迟相位与实测土壤湿度间的相关系数分别为0.97和0.95、土壤湿度拟合残差的均方根误差分别为0.010和0.012;同时,方案2和方案4还取得了较高的土壤湿度预报精度,土壤湿度预测值与土壤湿度实测值间的相关系数分别为0.92和0.91、土壤湿度预报残差的均方根误差分别为0.016和0.023;此外,相比于方案4,方案2在采用抗差估计解求延迟相位的基础上,采用多系统多卫星组合进一步提升了延迟相位的估值精度,从而不仅避免了复杂的选星过程,而且还获得了更好的建模效果和更高的土壤湿度预报精度。展开更多
BACKGROUND Postoperative delayed bleeding(PDB) after gastric endoscopic submucosal dissection(ESD) is the most common adverse event in patients receiving antithrombotics even with second-look endoscopy. Moreover, with...BACKGROUND Postoperative delayed bleeding(PDB) after gastric endoscopic submucosal dissection(ESD) is the most common adverse event in patients receiving antithrombotics even with second-look endoscopy. Moreover, with the increasing prevalence of cardiovascular and cerebrovascular diseases in an aging population with associated lifestyle-related diseases, an increasing number of patients receive antithrombotics. Several attempts have been made to prevent PDB in aging population;however, a consensus has yet to be reached.AIM To examine the efficacy of third-look endoscopy(TLE) for PDB prevention.METHODS One hundred patients with early gastric neoplasms receiving antithrombotics were prospectively enrolled and subjected to ESD with TLE between February 2017 and July 2019. The primary endpoint was PDB rate, which was compared with our preset threshold. Furthermore, we divided the bleeding period into early-and late-onset PDB(E-PDB and L-PDB, respectively) and analyzed its rate. As a secondary analysis, we compared PDB rates with those of a historical control group, using propensity score matching, and calculated the PDB rates per antithrombotic agent use in each group.RESULTS In total, 96 patients and 114 specimens were finally evaluated. The overall PDB rate was 7.9%(9/114) [90%CI: 4.7-13.1, P = 0.005], while the late-and early-onset PDB rates(L-PDB and E-PDB) were 5.3% [90%CI: 2.7-9.9, P < 0.0001] and 2.6% [90%CI: 1.1-6.4, P = 0.51], respectively. Propensity score matching generated 58 matched pairs for TLE and control groups. No differences were found in overall PDB incidence(10.3% vs 20.7%, P = 0.12), whereas L-PDB occurrence significantly differed(5.2% vs 17.2%, P = 0.04) between groups. Considering antithrombotics' use, the overall PDB rate was higher for direct oral anticoagulants and multiple antithrombotics in the control group, while L-PDB incidence was lower in the TLE group for these agents(8.7% vs 23.1% and 5.0% vs 29.4%, respectively).CONCLUSION TLE for gastric ESD reduces overall PDB, and especially L展开更多
BACKGROUND： The various combination of multiphase enhancement multislice spiral CT （MSCT） makes the diagno- sis of a small hepatocellular carcinoma （sHCC） on the back- ground of liver cirrhosis possible. This stu...BACKGROUND： The various combination of multiphase enhancement multislice spiral CT （MSCT） makes the diagno- sis of a small hepatocellular carcinoma （sHCC） on the back- ground of liver cirrhosis possible. This study was to explore whether the combination of MSCT enhancement scan and alpha-fetoprotein （AFP） level ficiency for sHCC. could increase the diagnostic ef- METHODS： This study included 35 sHCC patients and 52 cir- rhotic patients without image evidence of HCC as a control group. The diagnoses were made by three radiologists em- ploying a 5-point rating scale, with postoperative pathologic results as the gold standard. Receiver operating characteristic （ROC） curve analysis was performed to evaluate the diag- nostic value of the three MSCT combination modes （arterial phase＋portal-venous phase, arterial phase＋delayed phase, arterial phase＋portal-venous phase＋delayed phase） and AFP levels for sHCC on the background of liver cirrhosis. RESULTS： The area under ROC curve （AUC）, sensitivity, and specificity of the combination of arterial phase＋portal- venous phase＋delayed phase were 0.93, 93%, and 82%, respectively. The average AUC of the arterial phase＋portal- venous phase＋delayed phase combination was significantly greater than that of the arterial phase＋portal-venous phase （AUC=0.84, P=0.01） and arterial phase＋delayed phase （AUC=0.85, P=0.03）. Arterial phase＋portal-venous phase had a smaller AUC （0.84） than arterial phase＋delayed phase （0.85）, but the difference was insignificant （P=0.15）. After combining MSCT enhancement scan with AFP, the AUC, sensitivity, and specificity were 0.95, 94%, and 83%, respectively, indicating a greatly increased diagnostic efficiency for sHCC. CONCLUSIONS： The combination of AFP and 3 phases MSCT enhancement scan could increase the diagnostic efficiency for sHCC on the background of liver cirrhosis. The application of ROC curve analysis has provided a new method and reference in HCC diagnosis.展开更多
文摘There is continuing disparity between demand for and supply of kidneys for transplantation. This review describes the current state of kidney donation after cardiac death （DCD） and provides recommendations for a way forward. The conversion rate for potential DCD donors varies from 40%-80%. Compared to con-trolled DCD, uncontrolled DCD is more labour intensive, has a lower conversion rate and a higher discard rate. The super-rapid laparotomy technique involving direct aortic cannulation is preferred over in situ perfusion in controlled DCD donation and is associated with lower kidney discard rates, shorter warm ischaemia times and higher graft survival rates. DCD kidneys showed a 5.73-fold increase in the incidence of delayed graft function （DGF） and a higher primary non function rate compared to donation after brain death kidneys, but the long term graft function is equivalent between the two. The cold ischaemia time is a controllable factor that signifcantly infuences the outcome of allografts, for example, limiting it to 〈 12 h markedly reduces DGF. DCD kidneys from donors 〈 50 function like stan-dard criteria kidneys and should be viewed as such. As the majority of DCD kidneys are from controlled dona-tion, incorporation of uncontrolled donation will expand the donor pool. Efforts to maximise the supply of kid-neys from DCD include： implementing organ recovery from emergency department setting; improving family consent rate; utilising technological developments to optimise organs either prior to recovery from donors or during storage; improving organ allocation to ensure best utility; and improving viability testing to reduce primary non function.
文摘针对基于单系统单卫星GNSS-MR(GNSS Multipath Reflectometry)土壤湿度反演的可靠性不高、实际可操作性不强和最小二乘估计不具鲁棒性的缺点,为获取更优的延迟相位估值,并改善GNSS-MR土壤湿度反演的可靠性和实际可操作性,同时简化繁杂的选星过程,提出了一种基于抗差估计的多系统多卫星组合GNSS-MR土壤湿度反演算法。该算法首先顾及多径环境的差异性、多径误差的周期特性等进行信噪比SNR(Signal to NoiseRatio)观测值的筛选,然后采用基于IGGⅢ(Weight Function Ⅲ Developed by Institute of Geodesy and Geophysics)权函数的抗差估计解求延迟相位,进而获得表征土壤湿度变化趋势的延迟相位组合。实验结果表明,相较于未采用抗差估计的多系统多卫星组合(方案1)和单卫星组合(方案3),得益于抗差估计良好的鲁棒性,基于抗差估计的多系统多卫星组合(方案2)和单卫星组合(方案4)获得了较高的建模精度,所得延迟相位与实测土壤湿度间的相关系数分别为0.97和0.95、土壤湿度拟合残差的均方根误差分别为0.010和0.012;同时,方案2和方案4还取得了较高的土壤湿度预报精度,土壤湿度预测值与土壤湿度实测值间的相关系数分别为0.92和0.91、土壤湿度预报残差的均方根误差分别为0.016和0.023;此外,相比于方案4,方案2在采用抗差估计解求延迟相位的基础上,采用多系统多卫星组合进一步提升了延迟相位的估值精度,从而不仅避免了复杂的选星过程,而且还获得了更好的建模效果和更高的土壤湿度预报精度。
文摘BACKGROUND Postoperative delayed bleeding(PDB) after gastric endoscopic submucosal dissection(ESD) is the most common adverse event in patients receiving antithrombotics even with second-look endoscopy. Moreover, with the increasing prevalence of cardiovascular and cerebrovascular diseases in an aging population with associated lifestyle-related diseases, an increasing number of patients receive antithrombotics. Several attempts have been made to prevent PDB in aging population;however, a consensus has yet to be reached.AIM To examine the efficacy of third-look endoscopy(TLE) for PDB prevention.METHODS One hundred patients with early gastric neoplasms receiving antithrombotics were prospectively enrolled and subjected to ESD with TLE between February 2017 and July 2019. The primary endpoint was PDB rate, which was compared with our preset threshold. Furthermore, we divided the bleeding period into early-and late-onset PDB(E-PDB and L-PDB, respectively) and analyzed its rate. As a secondary analysis, we compared PDB rates with those of a historical control group, using propensity score matching, and calculated the PDB rates per antithrombotic agent use in each group.RESULTS In total, 96 patients and 114 specimens were finally evaluated. The overall PDB rate was 7.9%(9/114) [90%CI: 4.7-13.1, P = 0.005], while the late-and early-onset PDB rates(L-PDB and E-PDB) were 5.3% [90%CI: 2.7-9.9, P < 0.0001] and 2.6% [90%CI: 1.1-6.4, P = 0.51], respectively. Propensity score matching generated 58 matched pairs for TLE and control groups. No differences were found in overall PDB incidence(10.3% vs 20.7%, P = 0.12), whereas L-PDB occurrence significantly differed(5.2% vs 17.2%, P = 0.04) between groups. Considering antithrombotics' use, the overall PDB rate was higher for direct oral anticoagulants and multiple antithrombotics in the control group, while L-PDB incidence was lower in the TLE group for these agents(8.7% vs 23.1% and 5.0% vs 29.4%, respectively).CONCLUSION TLE for gastric ESD reduces overall PDB, and especially L
基金supported by grants from the National Natural Science Foundation of China(81301275,81471736 and 81671760)the National Science and Technology Pillar Program during the Twelfth Five-Year Plan Period(2015BAI01B09)Heilongjiang Province Foundation for Returness(LC2013C38)
文摘BACKGROUND： The various combination of multiphase enhancement multislice spiral CT （MSCT） makes the diagno- sis of a small hepatocellular carcinoma （sHCC） on the back- ground of liver cirrhosis possible. This study was to explore whether the combination of MSCT enhancement scan and alpha-fetoprotein （AFP） level ficiency for sHCC. could increase the diagnostic ef- METHODS： This study included 35 sHCC patients and 52 cir- rhotic patients without image evidence of HCC as a control group. The diagnoses were made by three radiologists em- ploying a 5-point rating scale, with postoperative pathologic results as the gold standard. Receiver operating characteristic （ROC） curve analysis was performed to evaluate the diag- nostic value of the three MSCT combination modes （arterial phase＋portal-venous phase, arterial phase＋delayed phase, arterial phase＋portal-venous phase＋delayed phase） and AFP levels for sHCC on the background of liver cirrhosis. RESULTS： The area under ROC curve （AUC）, sensitivity, and specificity of the combination of arterial phase＋portal- venous phase＋delayed phase were 0.93, 93%, and 82%, respectively. The average AUC of the arterial phase＋portal- venous phase＋delayed phase combination was significantly greater than that of the arterial phase＋portal-venous phase （AUC=0.84, P=0.01） and arterial phase＋delayed phase （AUC=0.85, P=0.03）. Arterial phase＋portal-venous phase had a smaller AUC （0.84） than arterial phase＋delayed phase （0.85）, but the difference was insignificant （P=0.15）. After combining MSCT enhancement scan with AFP, the AUC, sensitivity, and specificity were 0.95, 94%, and 83%, respectively, indicating a greatly increased diagnostic efficiency for sHCC. CONCLUSIONS： The combination of AFP and 3 phases MSCT enhancement scan could increase the diagnostic efficiency for sHCC on the background of liver cirrhosis. The application of ROC curve analysis has provided a new method and reference in HCC diagnosis.
