Selenium is an essential trace element for human beings and it plays a significant role for the health of human nervous system.The strong antioxidant effect of selenium endows the element with the ability to treat var...Selenium is an essential trace element for human beings and it plays a significant role for the health of human nervous system.The strong antioxidant effect of selenium endows the element with the ability to treat various diseases,including Alzheimer's disease(AD).In the body,selenium exists in the forms of selenoproteins,which could treat AD through various pathways,such as inhibiting peroxidation,inhibiting apoptosis signal pathway,reducing the levels of Aβin neurons and alleviating Tau protein caused by pathological damage.This article aims to comprehensively elaborate on the relationship between selenium and AD.展开更多
Dear Editor,Varicocele(VC)is a vascular condition characterized by abnormal tortuosity and dilation of the pampiniform plexus veins within the spermatic cord.VC is commonly observed in young adults,predominantly on th...Dear Editor,Varicocele(VC)is a vascular condition characterized by abnormal tortuosity and dilation of the pampiniform plexus veins within the spermatic cord.VC is commonly observed in young adults,predominantly on the left side;it is a frequent cause of male infertility and can lead to testicular hypofunction,pain,and discomfort.Microsurgical varicocelectomy is the gold standard for treating infertility caused by VC.VC repair is strongly recommended for couple infertility,oligoasthenoteratozoospermia(OAT),Grade 2 or 3 clinical VC,partner age<37 years,patient age<40 years,or testicular hypotrophy in children and adolescents.展开更多
Uronic acids are prevalent components of crucial glycoconjugates,pivotal in various biological processes.In nature,NDP-uronic acids,the nucleosides-activated uronic acids,serve as glycosylation donors catalyzed by uro...Uronic acids are prevalent components of crucial glycoconjugates,pivotal in various biological processes.In nature,NDP-uronic acids,the nucleosides-activated uronic acids,serve as glycosylation donors catalyzed by uronosyltransferases(UATs)to construct glycans containing uronic acids.Despite their biological importance,the synthesis of naturally occurring NDP-uronic acids on a large scale remains challenging.Here,we developed an oxidation reaction insertion strategy for the efficient synthesis of NDP-uronic acids,and 11 NDP-uronic acids were successfully prepared in good yield and on a large scale.The prepared NDP-uronic acids can be used to explore new uronosyltransferases and synthesize uronic acids containing carbohydrates for fundamental research.展开更多
本文对空间发展的湍流气固两相平面混合层流动进行了大涡模拟研究,其中气相亚网格尺度(SGS)使用结构函数模型,气相控制方程组采用SIMPLE方法求解,固体颗粒运动用拉格朗日方法计算。计算结果正确重现了流体涡结构的卷起、合并和破碎过...本文对空间发展的湍流气固两相平面混合层流动进行了大涡模拟研究,其中气相亚网格尺度(SGS)使用结构函数模型,气相控制方程组采用SIMPLE方法求解,固体颗粒运动用拉格朗日方法计算。计算结果正确重现了流体涡结构的卷起、合并和破碎过程,以及小尺寸颗粒在涡边缘(低涡度区)的局部富集现象。对直径分别为42μm、72μm和135μm分别进行了模拟,并将统计结果和实验测量结果(Hishida et al[1])比较,表明两者的平均速度吻合很好,但颗粒数密度和脉动速度存在较明显的差异,因此有必要对亚网格应力和颗粒之间的耦合作用以及拟序结构的三维性对颗粒运动的影响开展深入研究。展开更多
目的比较硝酸甘油介入^(99)Tc^m-tetrofosmin SPECT 心肌血流灌注显像与^(18)F-FDG PET 心肌代谢显像评估心肌活力的价值。方法既往有心肌梗死史伴左心功能不全经冠状动脉造影确诊为冠心病的患者36例,行二日法静息和硝酸甘油介入^(99)Tc...目的比较硝酸甘油介入^(99)Tc^m-tetrofosmin SPECT 心肌血流灌注显像与^(18)F-FDG PET 心肌代谢显像评估心肌活力的价值。方法既往有心肌梗死史伴左心功能不全经冠状动脉造影确诊为冠心病的患者36例,行二日法静息和硝酸甘油介入^(99)Tc^m-tetrofosmin SPECT 显像,并在1周内再行^(18)F-FDG PET 心肌代谢显像及静息超声心动图检查。将左心室分成13个节段,分析超声心动图室壁运动,并分析相同节段^(99)Tc^m-tetrofosmin 与^(18)F-FDG 的相对摄取比值,以^(99)Tc^m-tetrofosmin 摄取比值55%,^(18)F-FDG 摄取比值50%为判断心肌活力有无的阈值。以 k 统计比较3种方法的一致性。结果超声心动图示131个节段呈无运动或反向运动。^(99)Tc^m-tetrofosmin 静息显像示其中78个节段(60%)心肌有活力,53个节段(40%)无活力。该53个节段中14个(26%)在硝酸甘油介入后可见再填充,余39个节段无改变。在^(18)F-FDG PET 显像中,硝酸甘油介入显像再填充节段的心肌放射性摄取明显增高。再填充节段与无填充节段比较,心肌 FDG 摄取分别为(76±15)%和(58±17)%,差异有统计学意义(P<0.01)。硝酸甘油介入显像中,92个心肌节段(70%)有活力,39个无活力。tetrofosmin静息显像评估心肌活力与 FDG PET 显像比较,k 值为0.35,而硝酸甘油介入^(99)Tc^m-tetrofosmin SPECT与^(18)F-FDG PET 显像结果比较,k 值为0.53。结论硝酸甘油介入^(99)Tc^m-tetrofosmin SPECT 显像可提高对心肌活力的检测能力,与^(18)F-FDG PET 心肌代谢显像有很好的一致性。展开更多
基金the Yangzhou City and Yangzhou University Cooperation Program(No.YZ2023209)the Sele Valley Scholars Basic Research Project(No.2301)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)for support。
文摘Selenium is an essential trace element for human beings and it plays a significant role for the health of human nervous system.The strong antioxidant effect of selenium endows the element with the ability to treat various diseases,including Alzheimer's disease(AD).In the body,selenium exists in the forms of selenoproteins,which could treat AD through various pathways,such as inhibiting peroxidation,inhibiting apoptosis signal pathway,reducing the levels of Aβin neurons and alleviating Tau protein caused by pathological damage.This article aims to comprehensively elaborate on the relationship between selenium and AD.
文摘Dear Editor,Varicocele(VC)is a vascular condition characterized by abnormal tortuosity and dilation of the pampiniform plexus veins within the spermatic cord.VC is commonly observed in young adults,predominantly on the left side;it is a frequent cause of male infertility and can lead to testicular hypofunction,pain,and discomfort.Microsurgical varicocelectomy is the gold standard for treating infertility caused by VC.VC repair is strongly recommended for couple infertility,oligoasthenoteratozoospermia(OAT),Grade 2 or 3 clinical VC,partner age<37 years,patient age<40 years,or testicular hypotrophy in children and adolescents.
基金financially supported by National Natural Science Foundation of China(No.22207113 to J.Zhang)Guangdong Basic and Applied Basic Research Foundation(No.2021A1515110588to J.Zhang)Natural Science Foundation of Shanghai Municipality(No.22ZR1474000 to L.Wen)。
文摘Uronic acids are prevalent components of crucial glycoconjugates,pivotal in various biological processes.In nature,NDP-uronic acids,the nucleosides-activated uronic acids,serve as glycosylation donors catalyzed by uronosyltransferases(UATs)to construct glycans containing uronic acids.Despite their biological importance,the synthesis of naturally occurring NDP-uronic acids on a large scale remains challenging.Here,we developed an oxidation reaction insertion strategy for the efficient synthesis of NDP-uronic acids,and 11 NDP-uronic acids were successfully prepared in good yield and on a large scale.The prepared NDP-uronic acids can be used to explore new uronosyltransferases and synthesize uronic acids containing carbohydrates for fundamental research.
文摘本文对空间发展的湍流气固两相平面混合层流动进行了大涡模拟研究,其中气相亚网格尺度(SGS)使用结构函数模型,气相控制方程组采用SIMPLE方法求解,固体颗粒运动用拉格朗日方法计算。计算结果正确重现了流体涡结构的卷起、合并和破碎过程,以及小尺寸颗粒在涡边缘(低涡度区)的局部富集现象。对直径分别为42μm、72μm和135μm分别进行了模拟,并将统计结果和实验测量结果(Hishida et al[1])比较,表明两者的平均速度吻合很好,但颗粒数密度和脉动速度存在较明显的差异,因此有必要对亚网格应力和颗粒之间的耦合作用以及拟序结构的三维性对颗粒运动的影响开展深入研究。
文摘目的比较硝酸甘油介入^(99)Tc^m-tetrofosmin SPECT 心肌血流灌注显像与^(18)F-FDG PET 心肌代谢显像评估心肌活力的价值。方法既往有心肌梗死史伴左心功能不全经冠状动脉造影确诊为冠心病的患者36例,行二日法静息和硝酸甘油介入^(99)Tc^m-tetrofosmin SPECT 显像,并在1周内再行^(18)F-FDG PET 心肌代谢显像及静息超声心动图检查。将左心室分成13个节段,分析超声心动图室壁运动,并分析相同节段^(99)Tc^m-tetrofosmin 与^(18)F-FDG 的相对摄取比值,以^(99)Tc^m-tetrofosmin 摄取比值55%,^(18)F-FDG 摄取比值50%为判断心肌活力有无的阈值。以 k 统计比较3种方法的一致性。结果超声心动图示131个节段呈无运动或反向运动。^(99)Tc^m-tetrofosmin 静息显像示其中78个节段(60%)心肌有活力,53个节段(40%)无活力。该53个节段中14个(26%)在硝酸甘油介入后可见再填充,余39个节段无改变。在^(18)F-FDG PET 显像中,硝酸甘油介入显像再填充节段的心肌放射性摄取明显增高。再填充节段与无填充节段比较,心肌 FDG 摄取分别为(76±15)%和(58±17)%,差异有统计学意义(P<0.01)。硝酸甘油介入显像中,92个心肌节段(70%)有活力,39个无活力。tetrofosmin静息显像评估心肌活力与 FDG PET 显像比较,k 值为0.35,而硝酸甘油介入^(99)Tc^m-tetrofosmin SPECT与^(18)F-FDG PET 显像结果比较,k 值为0.53。结论硝酸甘油介入^(99)Tc^m-tetrofosmin SPECT 显像可提高对心肌活力的检测能力,与^(18)F-FDG PET 心肌代谢显像有很好的一致性。