Changes of CO 2/H 2O exchange parameters were continually measured in winter wheat under different water stress stages.The results showed that photosynthesis rate and transpiration rate of winter wheat in water stress...Changes of CO 2/H 2O exchange parameters were continually measured in winter wheat under different water stress stages.The results showed that photosynthesis rate and transpiration rate of winter wheat in water stress conditions were obviously lower than that in non stress conditions.After water stress,both of them slowly increased and even overtook that on sufficient irrigation treatment. Responses of winter wheat to water stress in different growth stages were different.To some extent, water stress can improve crop water use efficiency,speed up the process of milking.Under water stress condition,stomatal conductance limited diurnal changes of photosynthesis and transpiration in the morning but not in the afternoon.Transpiration is more sensitive to water stress than photosynthesis.展开更多
The similarities and differences in seepage flow evolution laws of CH4 and CO2 during complete stress- strain process of samples were comparatively analyzed. The results show that the seepage flow evolution laws of CH...The similarities and differences in seepage flow evolution laws of CH4 and CO2 during complete stress- strain process of samples were comparatively analyzed. The results show that the seepage flow evolution laws of CH4 and CO2 are extremely similar during the stress-strain process, showing that the character- istic first decreased and then increased. A mathematical model was also established according to the rela- tionship of seepage velocity and axial strain. However, due to the strong adsorption ability of CO2, the coal samples generated a more serious ''Klinkenberg effect'' under the condition of CO2. Owing to this, the CO2 seepage flow resulted into occurrence of ''stagnation'' phenomenon during the late linear elastic stage II. In the strain consolidation stage III, the increment rate of CH4 seepage velocity was significantly greater than that of CO2. In the stress descent stage IV, when the axial load reached the peak pressure of coal, the increment rates of CH4 seepage velocity presented a turning point. But the changing rate of CO2 seepage velocity still remained slow and a turning point was presented at one time after the peak of thestrain pressure, which showed an obvious feature of hysteresis.展开更多
目的探讨前列地尔联合阿卡波糖治疗2型糖尿病肾病的疗效及对患者氧化应激水平的影响。方法将本院收治的85例2型糖尿病肾病患者按治疗方案不同分为对照组（40例）和观察组（45例）。对照组在常规治疗的基础上给予阿卡波糖100 m g ，3次...目的探讨前列地尔联合阿卡波糖治疗2型糖尿病肾病的疗效及对患者氧化应激水平的影响。方法将本院收治的85例2型糖尿病肾病患者按治疗方案不同分为对照组（40例）和观察组（45例）。对照组在常规治疗的基础上给予阿卡波糖100 m g ，3次／日，观察组在对照组的基础上联合应用前列地尔10μg ，1次／日进行治疗。4周后观察比较两组患者临床疗效、肾功能、丙二醛（MDA），超氧化物歧化酶（SOD）水平变化及不良反应发生情况。结果观察组的总治疗有效率为88．9％，明显高于对照组的77．5％，且两组相比较差异有显著性（Z＝2．15，P＜0．05）。经治疗后观察组肾功能指标血尿素氮（BUN）和血肌酐（SCr）、尿总蛋白明显下降，SOD明显升高，MDA明显下降，与对照组相比差异均有显著性（ P ＜0．05）。治疗过程中两组患者均无明显严重不良反应发生。结论前列地尔联合阿卡波糖可以显著提高2型糖尿病肾病的治疗有效率，改善肾功能，减轻氧化应激水平，且不良反应轻微，值得临床上推广应用。展开更多
In face of climate change catastrophes, understanding the thermal limits and optimal physiological thermal window food crop is of particular urgency. This research aims to evaluate: 1) how physiological performances o...In face of climate change catastrophes, understanding the thermal limits and optimal physiological thermal window food crop is of particular urgency. This research aims to evaluate: 1) how physiological performances of plant will change with increasing chronic and acute heat stress;2) if the examined parameters form a hierarchy in terms of thermal tolerance;and 3) the optimal thermal window and critical temperatures of the examined plants with response to chronic and acute heat stress. Six temperate vegetables were subjected to chronic and acute heat stress and a suite of physiological parameters were evaluated. Dose responses were observed in shoot fresh weight, photosynthetic gas exchange, photosynthetic oxygen evolution, electron transfer rate, photo- and non-photochemical quenching with significant drop in performance as early as 28°C for selected species. Conversely, ratio of variable to maximum fluorescence (F<sub>v</sub>/F<sub>m</sub>) was not affected by heat stress until 46°C in chronic heat stress. Examining the temperature at which a measured parameter’s performance dropped by 50% compared to control (LT<sub>50</sub>), a distinct hierarchy of the indices was observed for Canasta, recombinant inbred line 141, Lactuca serriola and Lactuca sativa (L. “Salinas”): shoot fresh weight, representing the highest integrated level of photosynthesis was the most sensitive to thermal stress (28°C - 30°C), followed by oxygen evolution (35°C - 45°C) while non-photochemical and photochemical quenching which is subcellular function of stress alleviation had a much higher capacity failure temperature (47°C - 60°C). It is expected that F<sub>v</sub>/F<sub>m</sub> ratio, a measurement of sub-cellular structural integrity, will approach that of non-photochemical and photochemical quenching, if not exceeding it. By examining the photosynthetic parameters via their hierarchy of biological organization, it can be inferred that plants like Arugula and recombinant inbred line 192 are already operating near their thermal limit and have less energetic investment into heat stress mediation whereas L. serriola prioritizes thermal tolerance at the expense of photosynthesis efficiency.展开更多
为了深入了解羧酸酯酶(Carboxylesterase,Car E)基因在烟草甲Lasioderma serricorne生长发育及响应CO_2气调胁迫方面的作用,在转录组测序基础上,利用RT-PCR技术克隆了烟草甲2个Car E基因c DNA全序列,对其分子特性和系统发育进行分析,并...为了深入了解羧酸酯酶(Carboxylesterase,Car E)基因在烟草甲Lasioderma serricorne生长发育及响应CO_2气调胁迫方面的作用,在转录组测序基础上,利用RT-PCR技术克隆了烟草甲2个Car E基因c DNA全序列,对其分子特性和系统发育进行分析,并利用实时定量PCR技术检测其在不同发育阶段及不同φ(CO_2)气调胁迫条件下的表达模式。获得了烟草甲2个Car E基因完整的开放阅读框,其长度为1 698 bp和1 695 bp,编码565和564个氨基酸。氨基酸同源性和系统进化树分析表明,它们均具有羧酸酯酶典型的保守结构域,且属于β家族,分别命名为Ls Car EB1和Ls Car EB2(Gen Bank登录号:MG189601和MG189602)。Ls Car EB1和Ls Car EB2在烟草甲的各发育阶段均有所表达,其中在高龄幼虫期的表达量较高,显著高于低龄幼虫、蛹和成虫期的表达水平。LC10、LC30和LC503种φ(CO_2)处理6 h后,Ls Car EB1和Ls Car EB2的mRNA表达量随胁迫φ(CO_2)升高而上调且显著高于对照组。推测Ls Car EB1和Ls Car EB2不仅对烟草甲的生长发育具有重要作用,而且是其响应CO_2气调胁迫的重要机制之一。展开更多
文摘Changes of CO 2/H 2O exchange parameters were continually measured in winter wheat under different water stress stages.The results showed that photosynthesis rate and transpiration rate of winter wheat in water stress conditions were obviously lower than that in non stress conditions.After water stress,both of them slowly increased and even overtook that on sufficient irrigation treatment. Responses of winter wheat to water stress in different growth stages were different.To some extent, water stress can improve crop water use efficiency,speed up the process of milking.Under water stress condition,stomatal conductance limited diurnal changes of photosynthesis and transpiration in the morning but not in the afternoon.Transpiration is more sensitive to water stress than photosynthesis.
基金supported by the National Natural Science Foundation of China (Nos. 51074197 and 50674111)the Natural Science Foundation of CQ CSTC (No. 2010BB6118)the Fundamental Research Funds for the Central Universities (No. CDJXS11241181)
文摘The similarities and differences in seepage flow evolution laws of CH4 and CO2 during complete stress- strain process of samples were comparatively analyzed. The results show that the seepage flow evolution laws of CH4 and CO2 are extremely similar during the stress-strain process, showing that the character- istic first decreased and then increased. A mathematical model was also established according to the rela- tionship of seepage velocity and axial strain. However, due to the strong adsorption ability of CO2, the coal samples generated a more serious ''Klinkenberg effect'' under the condition of CO2. Owing to this, the CO2 seepage flow resulted into occurrence of ''stagnation'' phenomenon during the late linear elastic stage II. In the strain consolidation stage III, the increment rate of CH4 seepage velocity was significantly greater than that of CO2. In the stress descent stage IV, when the axial load reached the peak pressure of coal, the increment rates of CH4 seepage velocity presented a turning point. But the changing rate of CO2 seepage velocity still remained slow and a turning point was presented at one time after the peak of thestrain pressure, which showed an obvious feature of hysteresis.
文摘目的探讨前列地尔联合阿卡波糖治疗2型糖尿病肾病的疗效及对患者氧化应激水平的影响。方法将本院收治的85例2型糖尿病肾病患者按治疗方案不同分为对照组（40例）和观察组（45例）。对照组在常规治疗的基础上给予阿卡波糖100 m g ，3次／日，观察组在对照组的基础上联合应用前列地尔10μg ，1次／日进行治疗。4周后观察比较两组患者临床疗效、肾功能、丙二醛（MDA），超氧化物歧化酶（SOD）水平变化及不良反应发生情况。结果观察组的总治疗有效率为88．9％，明显高于对照组的77．5％，且两组相比较差异有显著性（Z＝2．15，P＜0．05）。经治疗后观察组肾功能指标血尿素氮（BUN）和血肌酐（SCr）、尿总蛋白明显下降，SOD明显升高，MDA明显下降，与对照组相比差异均有显著性（ P ＜0．05）。治疗过程中两组患者均无明显严重不良反应发生。结论前列地尔联合阿卡波糖可以显著提高2型糖尿病肾病的治疗有效率，改善肾功能，减轻氧化应激水平，且不良反应轻微，值得临床上推广应用。
文摘In face of climate change catastrophes, understanding the thermal limits and optimal physiological thermal window food crop is of particular urgency. This research aims to evaluate: 1) how physiological performances of plant will change with increasing chronic and acute heat stress;2) if the examined parameters form a hierarchy in terms of thermal tolerance;and 3) the optimal thermal window and critical temperatures of the examined plants with response to chronic and acute heat stress. Six temperate vegetables were subjected to chronic and acute heat stress and a suite of physiological parameters were evaluated. Dose responses were observed in shoot fresh weight, photosynthetic gas exchange, photosynthetic oxygen evolution, electron transfer rate, photo- and non-photochemical quenching with significant drop in performance as early as 28°C for selected species. Conversely, ratio of variable to maximum fluorescence (F<sub>v</sub>/F<sub>m</sub>) was not affected by heat stress until 46°C in chronic heat stress. Examining the temperature at which a measured parameter’s performance dropped by 50% compared to control (LT<sub>50</sub>), a distinct hierarchy of the indices was observed for Canasta, recombinant inbred line 141, Lactuca serriola and Lactuca sativa (L. “Salinas”): shoot fresh weight, representing the highest integrated level of photosynthesis was the most sensitive to thermal stress (28°C - 30°C), followed by oxygen evolution (35°C - 45°C) while non-photochemical and photochemical quenching which is subcellular function of stress alleviation had a much higher capacity failure temperature (47°C - 60°C). It is expected that F<sub>v</sub>/F<sub>m</sub> ratio, a measurement of sub-cellular structural integrity, will approach that of non-photochemical and photochemical quenching, if not exceeding it. By examining the photosynthetic parameters via their hierarchy of biological organization, it can be inferred that plants like Arugula and recombinant inbred line 192 are already operating near their thermal limit and have less energetic investment into heat stress mediation whereas L. serriola prioritizes thermal tolerance at the expense of photosynthesis efficiency.
文摘为了深入了解羧酸酯酶(Carboxylesterase,Car E)基因在烟草甲Lasioderma serricorne生长发育及响应CO_2气调胁迫方面的作用,在转录组测序基础上,利用RT-PCR技术克隆了烟草甲2个Car E基因c DNA全序列,对其分子特性和系统发育进行分析,并利用实时定量PCR技术检测其在不同发育阶段及不同φ(CO_2)气调胁迫条件下的表达模式。获得了烟草甲2个Car E基因完整的开放阅读框,其长度为1 698 bp和1 695 bp,编码565和564个氨基酸。氨基酸同源性和系统进化树分析表明,它们均具有羧酸酯酶典型的保守结构域,且属于β家族,分别命名为Ls Car EB1和Ls Car EB2(Gen Bank登录号:MG189601和MG189602)。Ls Car EB1和Ls Car EB2在烟草甲的各发育阶段均有所表达,其中在高龄幼虫期的表达量较高,显著高于低龄幼虫、蛹和成虫期的表达水平。LC10、LC30和LC503种φ(CO_2)处理6 h后,Ls Car EB1和Ls Car EB2的mRNA表达量随胁迫φ(CO_2)升高而上调且显著高于对照组。推测Ls Car EB1和Ls Car EB2不仅对烟草甲的生长发育具有重要作用,而且是其响应CO_2气调胁迫的重要机制之一。
