The increase of atmospheric CO 2 concentration is indisputable. In such condition, photosynthetic response of leaf is relatively well studied, while the comparison of that between single leaf and whole canopy is less...The increase of atmospheric CO 2 concentration is indisputable. In such condition, photosynthetic response of leaf is relatively well studied, while the comparison of that between single leaf and whole canopy is less emphasized. The stimulation of elevated CO 2 on canopy photosynthesis may be different from that on single leaf level. In this study, leaf and canopy photosynthesis of rice (Oryza sativa L.) were studied throughout the growing season. High CO 2 and temperature had a synergetic stimulation on single leaf photosynthetic rate until grain filling. Photosynthesis of leaf was stimulated by high CO 2, although the stimulation was decreased by higher temperature at grain filling stage. On the other hand, the simulation of elevated CO 2 on canopy photosynthesis leveled off with time. Stimulation at canopy level disappeared by grain filling stage in both temperature treatments. Green leaf area index was not significantly affected by CO 2 at maturity, but greater in plants grown at higher temperature. Leaf nitrogen content decreased with the increase of CO 2 concentration although it was not statistically significant at maturity. Canopy respiration rate increased at flowering stage indicating higher carbon loss. Shading effect caused by leaf development reached maximum at flowering stage. The CO 2 stimulation on photosynthesis was greater in single leaf than in canopy. Since enhanced CO 2 significantly increased biomass of rice stems and panicles, increase in canopy respiration caused diminishment of CO 2 stimulation in canopy net photosynthesis. Leaf nitrogen in the canopy level decreased with CO 2 concentration and may eventually hasten CO 2 stimulation on canopy photosynthesis. Early senescence of canopy leaves in high CO 2 is also a possible cause.展开更多
观察点阵CO2激光术后联合重组贻贝粘蛋白水凝胶敷料疗效及安全性。方法 选取2022 年9月—2023年9月来我院皮肤科室治疗痤疮凹陷性瘢痕的患者60例,采用双盲数字法将其平均分为研究组30例和对照组30例,其中对照组患者使用点阵CO2激光治疗...观察点阵CO2激光术后联合重组贻贝粘蛋白水凝胶敷料疗效及安全性。方法 选取2022 年9月—2023年9月来我院皮肤科室治疗痤疮凹陷性瘢痕的患者60例,采用双盲数字法将其平均分为研究组30例和对照组30例,其中对照组患者使用点阵CO2激光治疗,研究组患者在采用点阵CO2激光的基础上联合重组贻贝粘蛋白水凝胶敷料治疗。治疗28d后对两组患者临床疗效、瘢痕皮损、面部红斑量、经表皮水分流失量、临床痤疮瘢痕情况(ECCA评分量表)、面部整体美学效果改善情况(GAIS评分量表)和治疗期间的安全性进行对比。结果 治疗28d后研究组患者的临床总治疗有效率明显高于对照组(93.33% vs 63.33%),差异有统计学意义(P<0.05);治疗后,研究组患者的急性炎症反应半定量评分明显低于对照组(1.53±0.37 vs 2.16±0.28),而平均脱痂时间明显短于对照组(6.34±1.36d vs 8.27±1.86d),差异有统计学意义(P<0.05);治疗后两组患者的ECCA权重评分较治疗前均显著降低,而两组患者的GAIS评分较治疗前显著升高,差异均具有统计学意义(P<0.05),其中研究组患者相较于对照组患者而言ECCA降低更多(15.78±5.28 vs 23.62±6.29),而GAIS升高更多(2.57±0.61 vs 2.13±0.56) ,差异具有统计学意义(P<0.05);两组不良反应发生率差异无统计学意义(P>0.05)。结论 重组贻贝粘蛋白水凝胶敷料联合点阵CO2激光治疗痤疮凹陷性瘢痕疗效确切,可减少点阵CO2激光术不良反应,缩短恢复期,提高皮肤屏障功能与美观度。展开更多
文摘The increase of atmospheric CO 2 concentration is indisputable. In such condition, photosynthetic response of leaf is relatively well studied, while the comparison of that between single leaf and whole canopy is less emphasized. The stimulation of elevated CO 2 on canopy photosynthesis may be different from that on single leaf level. In this study, leaf and canopy photosynthesis of rice (Oryza sativa L.) were studied throughout the growing season. High CO 2 and temperature had a synergetic stimulation on single leaf photosynthetic rate until grain filling. Photosynthesis of leaf was stimulated by high CO 2, although the stimulation was decreased by higher temperature at grain filling stage. On the other hand, the simulation of elevated CO 2 on canopy photosynthesis leveled off with time. Stimulation at canopy level disappeared by grain filling stage in both temperature treatments. Green leaf area index was not significantly affected by CO 2 at maturity, but greater in plants grown at higher temperature. Leaf nitrogen content decreased with the increase of CO 2 concentration although it was not statistically significant at maturity. Canopy respiration rate increased at flowering stage indicating higher carbon loss. Shading effect caused by leaf development reached maximum at flowering stage. The CO 2 stimulation on photosynthesis was greater in single leaf than in canopy. Since enhanced CO 2 significantly increased biomass of rice stems and panicles, increase in canopy respiration caused diminishment of CO 2 stimulation in canopy net photosynthesis. Leaf nitrogen in the canopy level decreased with CO 2 concentration and may eventually hasten CO 2 stimulation on canopy photosynthesis. Early senescence of canopy leaves in high CO 2 is also a possible cause.
文摘观察点阵CO2激光术后联合重组贻贝粘蛋白水凝胶敷料疗效及安全性。方法 选取2022 年9月—2023年9月来我院皮肤科室治疗痤疮凹陷性瘢痕的患者60例,采用双盲数字法将其平均分为研究组30例和对照组30例,其中对照组患者使用点阵CO2激光治疗,研究组患者在采用点阵CO2激光的基础上联合重组贻贝粘蛋白水凝胶敷料治疗。治疗28d后对两组患者临床疗效、瘢痕皮损、面部红斑量、经表皮水分流失量、临床痤疮瘢痕情况(ECCA评分量表)、面部整体美学效果改善情况(GAIS评分量表)和治疗期间的安全性进行对比。结果 治疗28d后研究组患者的临床总治疗有效率明显高于对照组(93.33% vs 63.33%),差异有统计学意义(P<0.05);治疗后,研究组患者的急性炎症反应半定量评分明显低于对照组(1.53±0.37 vs 2.16±0.28),而平均脱痂时间明显短于对照组(6.34±1.36d vs 8.27±1.86d),差异有统计学意义(P<0.05);治疗后两组患者的ECCA权重评分较治疗前均显著降低,而两组患者的GAIS评分较治疗前显著升高,差异均具有统计学意义(P<0.05),其中研究组患者相较于对照组患者而言ECCA降低更多(15.78±5.28 vs 23.62±6.29),而GAIS升高更多(2.57±0.61 vs 2.13±0.56) ,差异具有统计学意义(P<0.05);两组不良反应发生率差异无统计学意义(P>0.05)。结论 重组贻贝粘蛋白水凝胶敷料联合点阵CO2激光治疗痤疮凹陷性瘢痕疗效确切,可减少点阵CO2激光术不良反应,缩短恢复期,提高皮肤屏障功能与美观度。
