目的探讨慢性阻塞性肺疾病急性加重期(acute exacerhation of chronic obstructive pulmonary disease,AECOPD)患者治疗前后Th17/Treg免疫平衡、呼出气一氧化氮(fraction of exhaled nitric oxide,FeNO)水平变化及对预后的影响。方法选...目的探讨慢性阻塞性肺疾病急性加重期(acute exacerhation of chronic obstructive pulmonary disease,AECOPD)患者治疗前后Th17/Treg免疫平衡、呼出气一氧化氮(fraction of exhaled nitric oxide,FeNO)水平变化及对预后的影响。方法选取AECOPD患者126例,采用肺功能检测仪测定第1秒用力呼气量(forced expiratory volume in one second,FEV1)、第1秒用力呼气量占预计值百分比(FEV1%)、用力肺活量(forced vital capacity,FVC)、用力肺活量占预计值百分比(FVC%)、第1秒用力呼气量占用力肺活量的百分比(FEV1/FVC)。并使用一氧化氮测定仪检测FeNO水平,采用全身炎性反应综合征(systemic inflammaton response syndrome,SIRS)评分进行评分,采用流式细胞仪检测血清辅助性T细胞17(T help 17cells,Th17)、调节性T细胞(T Regulatory cells,Treg)水平,比较治疗前后患者肺功能指标、FeNO水平、SIRS评分、Th17/Treg水平等指标变化情况。结果治疗3个月后,AECOPD患者FEV1%、FEV1/FVC、Th17、Th17/Treg水平显著高于治疗前,FeNO、血清Treg水平、SIRS评分显著低于治疗前(P<0.05)。126例AECOPD患者治疗3个月后存活94例(74.60%);死亡32例(25.40%)。存活组FEV1%、FEV1/FVC、Treg水平显著高于死亡组,FeNO、Th17、Th17/Treg及SIRS评分显著低于死亡组(P<0.05)。多因素Logistic回归分析结果显示,治疗前FEV1%、FEV1/FVC、Treg是AECOPD患者预后的危险因素(P<0.05);FeNO、Th17、Th17/Treg、SIRS评分是AECOPD患者预后的保护因素(P<0.05)。结论AECOPD患者治疗后肺功能提高,Th17/Treg、FeNO降低,肺功能、Th17/Treg免疫平衡、FeNO水平对AECOPD患者疗效评估及预后判断具有重要意义。展开更多
Besides the natural selection, the crops cultivated today have experienced two episodes of strong artificial selection, domestic and modern breeding. Domestication led to giant genetic structure differentiation betwee...Besides the natural selection, the crops cultivated today have experienced two episodes of strong artificial selection, domestic and modern breeding. Domestication led to giant genetic structure differentiation between cultivars and their wild species, while modern breeding made further genetic structure differentiation between the modern varieties and the landraces. In a population, diversity of the loci under strong selection is significantly lower than that of other loci. At the same time, diversity in the genomic regions flanking these selected loci also declines in the process of selection. This phenomenon is called hitchhiking effects or selection sweep in genetics. Genomic regions with selection sweep (haplotype block) could be detected after draft genome scanning (genome typing) with molecular markers in a number of released varieties or natural populations. Marker/trait association analysis in these regions would detect the loci (or QTLs) even the favored alleles (genes) in breeding or natural adaptation. Fine scanning of these genomic regions would help to determine the sizes of haplotype blocks and to discover the key genes, thereby providing very valuable information for isolation of the key genes and molecular design of new varieties. Establishment of high density genetic linkage maps in the major crops and availability of high throughput genotyping platform make it possible to discover agronomic important genes through marker/trait association analysis. On the basis of available publications, we give a brief introduction of the hitchhiking effect mapping approach in this paper using plant height, 1 000-grain weight, and phosphorus-deficiency tolerance as examples in wheat.展开更多
建立了某型动车组铝合金焊接车体的有限元分析模型,对焊缝部位进行简化建模,焊缝与实际存在的差异在等效结构应力计算中进行修正;基于标准BS EN 12663—1:2010分析了车体承受的载荷,采用Box-Behnken正交矩阵设计确定了车体的9个疲劳载...建立了某型动车组铝合金焊接车体的有限元分析模型,对焊缝部位进行简化建模,焊缝与实际存在的差异在等效结构应力计算中进行修正;基于标准BS EN 12663—1:2010分析了车体承受的载荷,采用Box-Behnken正交矩阵设计确定了车体的9个疲劳载荷工况;对车体有限元模型施加多轴载荷,分析了车体侧墙上的4条长焊缝部位的应力分布,确定了6个应力因数计算的关注点;采用名义应力法和等效结构应力法计算车体侧墙焊缝的应力因数,对比分析了2种应力分析方法。分析结果表明:2种应力分析方法在循环次数为1.0×10^(7)的许用应力范围不同,名义应力为16.40 MPa,等效结构应力为26.61 MPa;6个关注点的名义应力范围均小于其等效结构应力范围,得到的车体焊缝6个关注点的名义应力和等效结构应力的应力因数分别为0.33、0.25、0.50、0.49、0.76、0.62和0.23、0.24、0.39、0.45、0.61、0.48;针对同一焊缝的关注点,名义应力法计算的应力因数大于采用等效结构应力法计算的应力因数;名义应力法存在很大的分散性,导致应力因数偏大,而等效结构应力法物理意义更明确,计算的应力因数更为合理。展开更多
文摘目的探讨慢性阻塞性肺疾病急性加重期(acute exacerhation of chronic obstructive pulmonary disease,AECOPD)患者治疗前后Th17/Treg免疫平衡、呼出气一氧化氮(fraction of exhaled nitric oxide,FeNO)水平变化及对预后的影响。方法选取AECOPD患者126例,采用肺功能检测仪测定第1秒用力呼气量(forced expiratory volume in one second,FEV1)、第1秒用力呼气量占预计值百分比(FEV1%)、用力肺活量(forced vital capacity,FVC)、用力肺活量占预计值百分比(FVC%)、第1秒用力呼气量占用力肺活量的百分比(FEV1/FVC)。并使用一氧化氮测定仪检测FeNO水平,采用全身炎性反应综合征(systemic inflammaton response syndrome,SIRS)评分进行评分,采用流式细胞仪检测血清辅助性T细胞17(T help 17cells,Th17)、调节性T细胞(T Regulatory cells,Treg)水平,比较治疗前后患者肺功能指标、FeNO水平、SIRS评分、Th17/Treg水平等指标变化情况。结果治疗3个月后,AECOPD患者FEV1%、FEV1/FVC、Th17、Th17/Treg水平显著高于治疗前,FeNO、血清Treg水平、SIRS评分显著低于治疗前(P<0.05)。126例AECOPD患者治疗3个月后存活94例(74.60%);死亡32例(25.40%)。存活组FEV1%、FEV1/FVC、Treg水平显著高于死亡组,FeNO、Th17、Th17/Treg及SIRS评分显著低于死亡组(P<0.05)。多因素Logistic回归分析结果显示,治疗前FEV1%、FEV1/FVC、Treg是AECOPD患者预后的危险因素(P<0.05);FeNO、Th17、Th17/Treg、SIRS评分是AECOPD患者预后的保护因素(P<0.05)。结论AECOPD患者治疗后肺功能提高,Th17/Treg、FeNO降低,肺功能、Th17/Treg免疫平衡、FeNO水平对AECOPD患者疗效评估及预后判断具有重要意义。
文摘Besides the natural selection, the crops cultivated today have experienced two episodes of strong artificial selection, domestic and modern breeding. Domestication led to giant genetic structure differentiation between cultivars and their wild species, while modern breeding made further genetic structure differentiation between the modern varieties and the landraces. In a population, diversity of the loci under strong selection is significantly lower than that of other loci. At the same time, diversity in the genomic regions flanking these selected loci also declines in the process of selection. This phenomenon is called hitchhiking effects or selection sweep in genetics. Genomic regions with selection sweep (haplotype block) could be detected after draft genome scanning (genome typing) with molecular markers in a number of released varieties or natural populations. Marker/trait association analysis in these regions would detect the loci (or QTLs) even the favored alleles (genes) in breeding or natural adaptation. Fine scanning of these genomic regions would help to determine the sizes of haplotype blocks and to discover the key genes, thereby providing very valuable information for isolation of the key genes and molecular design of new varieties. Establishment of high density genetic linkage maps in the major crops and availability of high throughput genotyping platform make it possible to discover agronomic important genes through marker/trait association analysis. On the basis of available publications, we give a brief introduction of the hitchhiking effect mapping approach in this paper using plant height, 1 000-grain weight, and phosphorus-deficiency tolerance as examples in wheat.
文摘建立了某型动车组铝合金焊接车体的有限元分析模型,对焊缝部位进行简化建模,焊缝与实际存在的差异在等效结构应力计算中进行修正;基于标准BS EN 12663—1:2010分析了车体承受的载荷,采用Box-Behnken正交矩阵设计确定了车体的9个疲劳载荷工况;对车体有限元模型施加多轴载荷,分析了车体侧墙上的4条长焊缝部位的应力分布,确定了6个应力因数计算的关注点;采用名义应力法和等效结构应力法计算车体侧墙焊缝的应力因数,对比分析了2种应力分析方法。分析结果表明:2种应力分析方法在循环次数为1.0×10^(7)的许用应力范围不同,名义应力为16.40 MPa,等效结构应力为26.61 MPa;6个关注点的名义应力范围均小于其等效结构应力范围,得到的车体焊缝6个关注点的名义应力和等效结构应力的应力因数分别为0.33、0.25、0.50、0.49、0.76、0.62和0.23、0.24、0.39、0.45、0.61、0.48;针对同一焊缝的关注点,名义应力法计算的应力因数大于采用等效结构应力法计算的应力因数;名义应力法存在很大的分散性,导致应力因数偏大,而等效结构应力法物理意义更明确,计算的应力因数更为合理。