目的探讨小潮气量通气和呼气末正压通气(positive end expiratory pressure,PEEP)结合压力控制通气(pressure controlled ventilation.PCV)对结核性毁损肺(tuberculous destroyed lung,TDL)患者全肺切除术单肺通气(one-lung ventilation...目的探讨小潮气量通气和呼气末正压通气(positive end expiratory pressure,PEEP)结合压力控制通气(pressure controlled ventilation.PCV)对结核性毁损肺(tuberculous destroyed lung,TDL)患者全肺切除术单肺通气(one-lung ventilation, OLV)呼吸力学、肺内分流(Qs/Qt).PaO2和术后肺部感染等的影响。方法经首都医科大学附属北京胸科医院医学伦理委员会批准,选取2016年8月至2018年3月在首都医科大学附属北京胸科医院接受择期开胸全肺切除手术的TDL患者为研究对象,共48例。采用随机数字表法将患者分为观察组和对照组,每组24例。观察组0LV期间潮气量6 ml kg.OLV开始即刻给予PCV通气?然后给予7 cm H20( 1cm H20=0.0098 kPa)的PEEP通气;对照组OLV期间潮气量8 ml/kg。记录0LV前(T1)、0LV开始后30 min(T2)及全肺切除术后5 min (T3)时气道峰压(Ppek)和平台压(Pplat);T1、T2、T3和术后6 h(T4)抽取动静脉血,测血气指标pH、PaC02和PaQ,并计算Qs/Qt值;术后第1天、第7天行临床肺部感染评分。计量资料组间比较,若方差齐,采用t检验,若方差不齐采用t'检验;组内比较采用重复测量设计的方差分析;计数资料比较采用X^2检验,均以P<0. 05为差异有统计学意义。结果 T2时与对照组比较,观察组Ppek明显降低[观察组:(21.0 + 2.2) cm H:0;对照组:(22. 4±2. 2) cm H20;t=—2.446,P=0.021];T2时与对照组比较,观察组P嗣明显降低[观察组:(19.7+2.2) cm H2O;对照组:(21.0+2.7) cm H20;t=-3.610,P = 0.001];T3时与对照组比较,观察组pH明显降低[观察组:7.3±0.053;对照组,7.37±0. 047;r =- 3.000, P = 0.006];T2时与对照组比较,观察组PaCQ明显升高[观察组:(44.0±2.2) mm Hg (1 mm Hg=0.133 kPa);对照组:(35.7±4.0) mm Hg;t=7.091 ,P=0.000];T2 时与对照组比较,观察组Qs/Qt明显降低[观察组:(21.4 + 5.4)%;对照组:(25.4±6.8)%;t=-0.256,p=0.020];T4时与对照组比较,观察组Pa02/FiO2明显升高[观察组:(181.2 + 29.0) mm Hg;对照组:(159. 1 ±25. 2) mm Hg;r =2.9384=0.009]。术后第1天,与对照组比较,观察组肺部感染评分明显降低[观察组:(4.7±0.6)分;对照组:(5.2±0.9)分;t=—2.567,7=0.017]。结论小潮气量和PEEP结合PCV的通气模式,在TDL患者开胸全肺切除手术OLV中可以较好的降低0LV期间气道压力、降低QS/Qt,改善术后內Q?降低术后第1天肺部感染的评分。展开更多
The objectives of this study were to determine how the distribution of photosynthetically active radiation （PAR） in a maize canopy affected basal internode strength and stalk lodging. The distributions of PAR within...The objectives of this study were to determine how the distribution of photosynthetically active radiation （PAR） in a maize canopy affected basal internode strength and stalk lodging. The distributions of PAR within the canopies of two maize cultivars （Zhongdan 909 and Xinyu 41） were altered by removing whole leaves or half leaves in different canopy layers. The results showed that removing whole leaves or half leaves above the three-ear-leaves （RAE and RAE/2） at flowering sig- nificantly increased. PAR at the ear and interception of PAR （IPAR） from the ear to middle of the ear and soil surface. These changes increased the structural carbohydrate content and rind penetration strength （RPS） of the third basal internode by 5.4-11.6% and reduced lodging by 4.2-7.8%. Removal of the first three leaves below the three-ear-leaves （RBE） before flowering significantly reduced IPAR from the ear to half way below the ear. This reduced the structural carbohydrate con- tent and the RPS of the third basal internode by 9.1-17.4% and increased lodging by 7.0-11.2%. Removal of the three lowest green leaves （RB） in the canopy before flowering increased PAR at the bottom of the canopy, but had no effect on the structural carbohydrate content of the basal internode, the RPS, and the lodging rate. Overall, the results indicated that the key factors affecting the basal internode strength formation and lodging were PAR at the ear and IPAR from the ear to halfway below the ear. Increasing PAR at the ear and IPAR from the ear to halfway below the ear could enhance lodging resistance by increasing the structural carbohydrate content and mechanical strength of the basal internode.展开更多
文摘目的探讨小潮气量通气和呼气末正压通气(positive end expiratory pressure,PEEP)结合压力控制通气(pressure controlled ventilation.PCV)对结核性毁损肺(tuberculous destroyed lung,TDL)患者全肺切除术单肺通气(one-lung ventilation, OLV)呼吸力学、肺内分流(Qs/Qt).PaO2和术后肺部感染等的影响。方法经首都医科大学附属北京胸科医院医学伦理委员会批准,选取2016年8月至2018年3月在首都医科大学附属北京胸科医院接受择期开胸全肺切除手术的TDL患者为研究对象,共48例。采用随机数字表法将患者分为观察组和对照组,每组24例。观察组0LV期间潮气量6 ml kg.OLV开始即刻给予PCV通气?然后给予7 cm H20( 1cm H20=0.0098 kPa)的PEEP通气;对照组OLV期间潮气量8 ml/kg。记录0LV前(T1)、0LV开始后30 min(T2)及全肺切除术后5 min (T3)时气道峰压(Ppek)和平台压(Pplat);T1、T2、T3和术后6 h(T4)抽取动静脉血,测血气指标pH、PaC02和PaQ,并计算Qs/Qt值;术后第1天、第7天行临床肺部感染评分。计量资料组间比较,若方差齐,采用t检验,若方差不齐采用t'检验;组内比较采用重复测量设计的方差分析;计数资料比较采用X^2检验,均以P<0. 05为差异有统计学意义。结果 T2时与对照组比较,观察组Ppek明显降低[观察组:(21.0 + 2.2) cm H:0;对照组:(22. 4±2. 2) cm H20;t=—2.446,P=0.021];T2时与对照组比较,观察组P嗣明显降低[观察组:(19.7+2.2) cm H2O;对照组:(21.0+2.7) cm H20;t=-3.610,P = 0.001];T3时与对照组比较,观察组pH明显降低[观察组:7.3±0.053;对照组,7.37±0. 047;r =- 3.000, P = 0.006];T2时与对照组比较,观察组PaCQ明显升高[观察组:(44.0±2.2) mm Hg (1 mm Hg=0.133 kPa);对照组:(35.7±4.0) mm Hg;t=7.091 ,P=0.000];T2 时与对照组比较,观察组Qs/Qt明显降低[观察组:(21.4 + 5.4)%;对照组:(25.4±6.8)%;t=-0.256,p=0.020];T4时与对照组比较,观察组Pa02/FiO2明显升高[观察组:(181.2 + 29.0) mm Hg;对照组:(159. 1 ±25. 2) mm Hg;r =2.9384=0.009]。术后第1天,与对照组比较,观察组肺部感染评分明显降低[观察组:(4.7±0.6)分;对照组:(5.2±0.9)分;t=—2.567,7=0.017]。结论小潮气量和PEEP结合PCV的通气模式,在TDL患者开胸全肺切除手术OLV中可以较好的降低0LV期间气道压力、降低QS/Qt,改善术后內Q?降低术后第1天肺部感染的评分。
基金support from the National Natural Science Foundation of China (31160261)
文摘The objectives of this study were to determine how the distribution of photosynthetically active radiation （PAR） in a maize canopy affected basal internode strength and stalk lodging. The distributions of PAR within the canopies of two maize cultivars （Zhongdan 909 and Xinyu 41） were altered by removing whole leaves or half leaves in different canopy layers. The results showed that removing whole leaves or half leaves above the three-ear-leaves （RAE and RAE/2） at flowering sig- nificantly increased. PAR at the ear and interception of PAR （IPAR） from the ear to middle of the ear and soil surface. These changes increased the structural carbohydrate content and rind penetration strength （RPS） of the third basal internode by 5.4-11.6% and reduced lodging by 4.2-7.8%. Removal of the first three leaves below the three-ear-leaves （RBE） before flowering significantly reduced IPAR from the ear to half way below the ear. This reduced the structural carbohydrate con- tent and the RPS of the third basal internode by 9.1-17.4% and increased lodging by 7.0-11.2%. Removal of the three lowest green leaves （RB） in the canopy before flowering increased PAR at the bottom of the canopy, but had no effect on the structural carbohydrate content of the basal internode, the RPS, and the lodging rate. Overall, the results indicated that the key factors affecting the basal internode strength formation and lodging were PAR at the ear and IPAR from the ear to halfway below the ear. Increasing PAR at the ear and IPAR from the ear to halfway below the ear could enhance lodging resistance by increasing the structural carbohydrate content and mechanical strength of the basal internode.
