Low light stress is one of the most important factors affecting photosynthesis and growth in winter production of cucumber （Cucumis sativus L.） in solar greenhouses in northern China. Here, two genotypes of cucumber...Low light stress is one of the most important factors affecting photosynthesis and growth in winter production of cucumber （Cucumis sativus L.） in solar greenhouses in northern China. Here, two genotypes of cucumber （Deltastar and Jinyan 2） are used to determine the effect of low light stress on Rubisco expression and photosynthesis of leaves from emergence to senescence. During leaf development, the net photosynthetic rate （PN）, stomatal conductance （gs）, Rubisco initial activity and activation state, transcript levels of rbcL and rbcS, and the abundance of rbcL and rbcS DNA in these two genotypes increase rapidly to reach maximum in 10-20 d, and then decrease gradually. Meanwhile, the actual photosystem II efficiency （OpSll） of cucumber leaves slowly increased in the early leaf developing stages, but it declined quickly in leaf senescent stages, accompanied by an increased non-photochemical quenching （NPQ）. Moreover, PN, gs, initial Rubisco activity, and abundance of protein, mRNA and DNA of Rubisco subunits of leaves grown under 100 μmol m^-2 s^-1 are lower, and require more time to reach their maxima than those grown under 600 μmol m^-2 s^-1 during leaf development. All these results suggest that lower photosynthetic capacity of cucumber leaves from emergence to senescence under low light stress is probably due to down-regulated Rubisco gene expression in transcript and protein levels, and decreased initial and total activity as well as activation state of Rubisco. Deltastar performs better than Jinyan 2 under low light stress.展开更多
目的探讨普通白光内镜(white light image,WLI)、超声内镜(endoscopic ultrasonography,EUS)、放大内镜结合窄带显像(magnifying endoscopy with narrow band imaging,ME-NBI)技术在早期胃癌内镜治疗适应症中的应用价值,为临床诊疗决策...目的探讨普通白光内镜(white light image,WLI)、超声内镜(endoscopic ultrasonography,EUS)、放大内镜结合窄带显像(magnifying endoscopy with narrow band imaging,ME-NBI)技术在早期胃癌内镜治疗适应症中的应用价值,为临床诊疗决策提供依据。方法纳入2013年12月–2020年10月在四川大学华西医院行内镜下黏膜剥离术且术后病理证实为早期胃癌患者的临床资料,比较WLI和EUS判断早期胃癌浸润深度的准确性、敏感性、特异性、阳性预测值、阴性预测值;分析ME-NBI预测早期胃癌分化类型的作用。结果共纳入280例患者(291处病变),其中行EUS检查199例(207处病变),ME-NBI检查160例(168处病变)患者。结果显示WLI诊断早期胃癌浸润深度的准确率为87.0%,优于EUS(46.4%,P<0.001),即使两者联合诊断准确性(87.4%)相较于单独使用WLI(87.0%)也并无明显提高。ME-NBI判断早期胃癌分化程度的总体准确率为92.3%(155/168),未分化型早期胃癌ME-NBI判断准确率低于分化型早期胃癌(41.2%vs.98.0%,P<0.001)。结论在早期胃癌内镜治疗适应症的评估中,WLI可较好的预测病变浸润深度,EUS价值有限;ME-NBI能较为准确地预测绝大部分早期胃癌的分化程度,尤其是分化型早期胃癌。展开更多
基金supported by China Agriculture Research System (CARS-25)the National Basic Research Program of China (973 Program, 2009CB11900)the National Key Technologies R&D Program of China (2011BAD12B01)
文摘Low light stress is one of the most important factors affecting photosynthesis and growth in winter production of cucumber （Cucumis sativus L.） in solar greenhouses in northern China. Here, two genotypes of cucumber （Deltastar and Jinyan 2） are used to determine the effect of low light stress on Rubisco expression and photosynthesis of leaves from emergence to senescence. During leaf development, the net photosynthetic rate （PN）, stomatal conductance （gs）, Rubisco initial activity and activation state, transcript levels of rbcL and rbcS, and the abundance of rbcL and rbcS DNA in these two genotypes increase rapidly to reach maximum in 10-20 d, and then decrease gradually. Meanwhile, the actual photosystem II efficiency （OpSll） of cucumber leaves slowly increased in the early leaf developing stages, but it declined quickly in leaf senescent stages, accompanied by an increased non-photochemical quenching （NPQ）. Moreover, PN, gs, initial Rubisco activity, and abundance of protein, mRNA and DNA of Rubisco subunits of leaves grown under 100 μmol m^-2 s^-1 are lower, and require more time to reach their maxima than those grown under 600 μmol m^-2 s^-1 during leaf development. All these results suggest that lower photosynthetic capacity of cucumber leaves from emergence to senescence under low light stress is probably due to down-regulated Rubisco gene expression in transcript and protein levels, and decreased initial and total activity as well as activation state of Rubisco. Deltastar performs better than Jinyan 2 under low light stress.
文摘目的探讨普通白光内镜(white light image,WLI)、超声内镜(endoscopic ultrasonography,EUS)、放大内镜结合窄带显像(magnifying endoscopy with narrow band imaging,ME-NBI)技术在早期胃癌内镜治疗适应症中的应用价值,为临床诊疗决策提供依据。方法纳入2013年12月–2020年10月在四川大学华西医院行内镜下黏膜剥离术且术后病理证实为早期胃癌患者的临床资料,比较WLI和EUS判断早期胃癌浸润深度的准确性、敏感性、特异性、阳性预测值、阴性预测值;分析ME-NBI预测早期胃癌分化类型的作用。结果共纳入280例患者(291处病变),其中行EUS检查199例(207处病变),ME-NBI检查160例(168处病变)患者。结果显示WLI诊断早期胃癌浸润深度的准确率为87.0%,优于EUS(46.4%,P<0.001),即使两者联合诊断准确性(87.4%)相较于单独使用WLI(87.0%)也并无明显提高。ME-NBI判断早期胃癌分化程度的总体准确率为92.3%(155/168),未分化型早期胃癌ME-NBI判断准确率低于分化型早期胃癌(41.2%vs.98.0%,P<0.001)。结论在早期胃癌内镜治疗适应症的评估中,WLI可较好的预测病变浸润深度,EUS价值有限;ME-NBI能较为准确地预测绝大部分早期胃癌的分化程度,尤其是分化型早期胃癌。
