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星状神经节阻滞稳定全麻气管内插管及切皮时应激反应的初步研究 被引量:37
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作者 赵春亭 王恩真 +3 位作者 张迎萍 苗传龙 王国苏 吴静 《首都医科大学学报》 CAS 2000年第2期125-127,共3页
为观察应用星状神经节阻滞 (SGB)后全麻诱导气管内插管及手术切皮时内分泌的变化 ,将神经外科择期手术病人按麻醉方法的不同 ,分为阻滞组 (S组 ,n =1 4 ,于麻醉诱导前 5min行左SGB)与对照组 (N组 ,n =1 4 )进行对比观察。测量入室 (t0 ... 为观察应用星状神经节阻滞 (SGB)后全麻诱导气管内插管及手术切皮时内分泌的变化 ,将神经外科择期手术病人按麻醉方法的不同 ,分为阻滞组 (S组 ,n =1 4 ,于麻醉诱导前 5min行左SGB)与对照组 (N组 ,n =1 4 )进行对比观察。测量入室 (t0 )、气管插管后 1min(t1)、手术开始切皮 (t2 ) 3个时间的血浆皮质醇 (COR)、催乳素 (PRL)和胰岛素 (INS)浓度以及收缩压 (SBP)、舒张压 (DBP)和心率 (HR)。结果 :S组 3个时间的COR及PRL呈下降趋势、INS呈上升趋势 ;N组 3个时间的COR及PRL呈上升趋势、INS呈下降趋势 ;且SBP、HR、COR和PRL组内差比较均为N组 >S组 (P <0 .0 5和P <0 .0 1 )。显示SGB后诱导气管内插管及切皮时的SBP、HR及COR、PRL和INS变化相对较小。提示全麻诱导前行SGB具有抑制气管内插管及手术切皮时应激反应和稳定血流动力学的作用。 展开更多
关键词 星状神经节阻滞 气管内插管 应激反应 全身麻醉
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Long-term changes in the fishery ecosystem structure of Laizhou Bay,China 被引量:39
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作者 JIN XianShi SHAN XiuJuan +3 位作者 LI XianSen WANG Jun CUI Yi ZUO Tao 《Science China Earth Sciences》 SCIE EI CAS 2013年第3期366-374,共9页
Laizhou Bay provides a critical spawning and nursery habitat for many fishery species, including commercially important spe- cies, such as Fenneropenaeus chinensis and Larimichthys polyactis. The bay is severely stres... Laizhou Bay provides a critical spawning and nursery habitat for many fishery species, including commercially important spe- cies, such as Fenneropenaeus chinensis and Larimichthys polyactis. The bay is severely stressed due to high fishing pressure and environmental changes. Based on the long-term ecosystem surveys in Laizhou Bay during the main spawning period (May) of most fishery species from 1959 to 2008, the responses of the Laizhou Bay fishery ecosystem were analyzed here, including regime shifts in species composition, biomass, species diversity, zooplankton, phytoplankton, and environmental variables. The dominant species of large-size and high economic value (e.g. Trichiurus haumela, L. polyactis) have been replaced by the short-lived, low-trophic-level planktivorous pelagic species (e.g. Setipinna taty, Engraulisjaponicus) since the 1980s, and it is probable that the small-sized pelagic fishes have been recently replaced by invertebrates (e.g. Oratosquilla oratoria, Crangon affinis). The biomass of fishery resources declined continuously from 423.6 kg haul 1 h-1 in 1959 to 164.6 kg haul-l h i in 1982, 37.7 kg haul-1 h-1 in 1993, and less than 8 kg haul 1 h-a in 1998-2008. Moreover, the biomass of zooplankton showed an increasing trend during 1959-2006, but showed a slight decline in 2008. The abundance of phytoplankton increased from 1959 through 1982, decreased substantially in 1993, and increased again until 2004. More recently, however, the phytoplankton abundance was very low. The sea surface temperature (SST) and sea bottom temperature (SBT) in May increased by 0.23~C a-~ and 0.16~C a-~, respectively, during 1982-2008. The salinity in May showed large fluctuations and reached its lowest val- ues in 2004 and 2006. The ratio of dissolved inorganic nitrogen (DIN) to dissolved inorganic phosphate (DIP) increased. However, the dissolved silicon (DSi):DIP and DSi:DIN ratios decreased to a low level during 1959-2008. These changes seri- ously impacted primary produ 展开更多
关键词 long-term changes fishery ecosystem multi-stress Laizhou Bay
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金花茶幼苗光合生理生态特性研究 被引量:28
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作者 杨期和 李旭群 +2 位作者 杨和生 韦霄 尹小娟 《北京林业大学学报》 CAS CSCD 北大核心 2010年第2期57-63,共7页
采用Li-6400便携式光合作用系统对金花茶盆栽幼苗光合生理特性进行研究。结果表明:1)在不遮阴的条件下,幼苗夏季光合作用有午休现象,最高峰出现在08:00,其净光合速率为3.38μmol/(m2·s);2)光饱和点和光补偿点都较低,分别为476.46和... 采用Li-6400便携式光合作用系统对金花茶盆栽幼苗光合生理特性进行研究。结果表明:1)在不遮阴的条件下,幼苗夏季光合作用有午休现象,最高峰出现在08:00,其净光合速率为3.38μmol/(m2·s);2)光饱和点和光补偿点都较低,分别为476.46和6.13μmol/(m2·s),是一种典型的阴生植物;3)在温度为30℃,光照强度为1000μmol/(m2·s),湿度为50%~60%的条件下,光合能力为12.58~13.50μmol/(m2·s),CO2浓度在25~1000μmol/mol的范围内,其净光合速率随浓度升高而显著上升,CO2饱和点约为1500.00μmol/mol,CO2补偿点为99.48μmol/mol,最大羧化效率为0.0118;4)幼苗喜热,在35℃下净光合速率最高,对低温有一定的适应能力,但不适应40℃的高温条件。5)幼苗不耐干旱,即使轻度水分亏缺也会抑制其光合作用。 展开更多
关键词 金花茶 幼苗 日动态 光响应 CO2响应 温度胁迫 水分胁迫
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温度变化对拉索频率与索力的影响 被引量:15
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作者 赵珧冰 孙测世 +1 位作者 彭剑 王连华 《应用力学学报》 CAS CSCD 北大核心 2013年第6期904-908,955-956,共5页
为研究温度变化对拉索索力与频率的影响,本文引入了拉索在温度变化作用下的平衡状态,通过求解相应的平衡方程及运动方程,得到了在温度变化的影响下索力与频率之间的关系式。数值计算结果表明:随着温度变化量的增加,拉索水平张力及其反... 为研究温度变化对拉索索力与频率的影响,本文引入了拉索在温度变化作用下的平衡状态,通过求解相应的平衡方程及运动方程,得到了在温度变化的影响下索力与频率之间的关系式。数值计算结果表明:随着温度变化量的增加,拉索水平张力及其反对称模态频率呈下降趋势;而对于一阶正对称模态而言,该阶频率与温度变化量之间的关系取决于拉索初始水平张力,具体情况分为两种,其一,当初始水平张力相对较小时,该阶频率会随着温度的上升而增大,其二,当初始水平张力相对较大时,该阶频率会随着温度的上升而下降;对于相同的温度变化条件,索力与频率的变化程度不一致,变化程度主要取决于拉索的初始张力大小。此外,温度的变化虽然明显改变了索力与频率的大小,但并没有改变索力与频率之间的本质关系。 展开更多
关键词 拉索 温度变化 索力 频率 热应力
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Long-time precipitation reduction and nitrogen deposition increase alter soil nitrogen dynamic by influencing soil bacterial communities and functional groups 被引量:11
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作者 Guoyong YAN Yajuan XING +3 位作者 Shijie HAN Junhui ZHANG Qinggui WANG Changcheng MU 《Pedosphere》 SCIE CAS CSCD 2020年第3期363-377,共15页
The effects of precipitation reduction and nitrogen deposition increase on soil bacterial communities and functions impact soil nitrogen cycling. Seasonal changes could modify the effects of precipitation reduction an... The effects of precipitation reduction and nitrogen deposition increase on soil bacterial communities and functions impact soil nitrogen cycling. Seasonal changes could modify the effects of precipitation reduction and nitrogen deposition increase on bacterial communities and functions by changing soil environments and properties. Understanding soil microbial communities and the seasonal response of functions to precipitation reduction and nitrogen deposition increase may be important for the accurate prediction of changes in the soil nitrogen dynamics. Thus, a long-term field simulation experiment of nitrogen deposition increase and throughfall exclusion was established to investigate soil bacterial communities’ response to nitrogen deposition increase and/or precipitation reduction, with no nitrogen deposition increase and no precipation reduction as a control, in a temperate forest. We examined soil bacterial communities(Illumina sequencing) under different treatments during the winter, freezing-thawing cycle periods(FTCs), and growing season. The bacterial functional groups were predicted by the FAPROTAX database. The results showed that nitrogen deposition increase, precipitation reduction, the combined effect of nitrogen deposition increase and precipitation reduction, and seasonal changes significantly altered the soil bacterial community composition.Interestingly, by combining the result of a previous study in which nitrogen deposition increase increased the nitrous oxide flux in the same experimental system, the loss of soil nitrogen was increased by the decrease in denitrification and increase of nitrification bacteria under nitrogen deposition increase,while ammonification bacteria significantly increased and N-fixing bacteria significantly decreased with precipitation reduction compared to the control. In relation to seasonal changes, the aromatic-degrading, cellulolytic, and ureolytic bacteria were lowest during FTCs, which indicated that FTCs might inhibit biodegradation. Nitrification and nitrite 展开更多
关键词 copiotrophic bacteria DENITRIFICATION multidimensional effect NITRIFICATION oligotrophic bacteria seasonal changes soil acidification water stress
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Effect of L-cysteine on remote organ injury in rats with severe acute pancreatitis induced by bile-pancreatic duct obstruction 被引量:5
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作者 Li-Juan Yang Rong Wan +2 位作者 Jia-Qing Shen Jie Shen Xing-Peng Wang 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2013年第4期428-435,共8页
BACKGROUND: Remote organ failure occurs in cases of acute pancreatitis (AP); however, the reports on AP induced by pancreatic duct obstruction are rare. In this study we determined the effect of L-cysteine on pancreat... BACKGROUND: Remote organ failure occurs in cases of acute pancreatitis (AP); however, the reports on AP induced by pancreatic duct obstruction are rare. In this study we determined the effect of L-cysteine on pancreaticobiliary inflammation and remote organ damage in rats after pancreaticobiliary duct ligation (PBDL). METHODS: AP was induced by PBDL in rats with 5/0 silk Sixty rats were randomly divided into 4 groups. Groups A and B were sham-operated groups that received injections of saline or L-cysteine (10 mg/kg) intraperitoneally (15 rats in each group). Groups C and D were PBDL groups that received injections of saline or L-cysteine (10 mg/kg) intraperitoneally (15 rats in each group). The tissue samples of the pancreas and remote organs such as the lung, liver, intestine and kidney were subsequently examined for pathological changes under a light microscope. The samples were also stored for the determination of malondialdehyde and glutathione levels. Blood urea nitrogen (BUN), plasma amylase, ALT and AST levels were determined spectrophotometrically using an automated analyzer. Also, we evaluated the effect of L-cysteine on remote organ injury in rats with AP induced by retrograde infusion of 3.5% sodium taurocholate (NaTc) into the bile-pancreatic duct. RESULTS: Varying degrees of injury in the pancreas, lung, liver intestine and kidney were observed in the rats 24 hours after PBDL. The severity of injury to the lung, liver and intestine was attenuated, while injury status was not changed significantly in the pancreas and kidney after L-cysteine treatment. Oxidativestress was also affected by L-cysteine in PBDL-treated rats. The concentration of tissue malondialdehyde decreased in the pancreas and remote organs of PBDL and L-cysteine administrated rats, and the concentration of glutathione increased more significantly than that of the model control group. However, L-cysteine administration reduced the severity of injury in remote organs but not in the pancreas in rats with NaTc-induced AP. CONCLUSION: L-c 展开更多
关键词 PANCREATITIS oxidative stress lung injury liver failure animal models pathological changes
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干旱区主导全球植被生产力增加趋势 被引量:5
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作者 王帅 傅伯杰 +8 位作者 魏芳莉 朴世龙 Fernando T.Maestre Lixin Wang Wenzhe Jiao 刘焱序 李琰 李长嘉 赵文武 《Science Bulletin》 SCIE EI CAS CSCD 2023年第2期224-232,M0004,共10页
旱区(drylands)是指年平均降雨量与潜在蒸散发之比小于0.65的区域,占全球陆地表面的42%,是最易受气候变化影响的地区之一.然而,目前关于旱区植被对气候变化的响应特征及其对全球变绿和陆地生态系统生产力变化的相对贡献仍不清楚.本研究... 旱区(drylands)是指年平均降雨量与潜在蒸散发之比小于0.65的区域,占全球陆地表面的42%,是最易受气候变化影响的地区之一.然而,目前关于旱区植被对气候变化的响应特征及其对全球变绿和陆地生态系统生产力变化的相对贡献仍不清楚.本研究通过集成模型和遥感数据分析发现,旱区对全球变绿的贡献较小,仅占33%±15%,但却主导了全球植被生产力(GPP)增加趋势,贡献达65%±16%旱区植被光合利用效率升高是解释变绿与生产力增加不一致的主要原因.旱区光能利用率主要受土壤水分的影响,大气水汽压差作用不显著,而非旱区主要受大气水汽压差的影响,土壤水的作用有限.因此,需要强调使用不同的水分胁迫指标来预测不同区域植被生产力变化的重要性,这也有助于理解较长时间尺度上植被绿度与生产力之间的解耦关系. 展开更多
关键词 光能利用率 水汽压差 气候变化影响 植被生产力 旱区 潜在蒸散发 相对贡献 集成模型
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基于应变软化模型的深基坑土钉加固分析 被引量:6
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作者 卢敦华 王星华 《解放军理工大学学报(自然科学版)》 EI 北大核心 2009年第1期61-66,共6页
为了更加真实地反映岩土体材料的特性,以某深基坑土钉加固工程为背景,建立相应的应变软化模型。分析土钉加固基坑过程中,基坑的变形和塑性区分布情况,以及不同位置和不同开挖过程中土钉的应力变化情况。结果表明:用FLAC3D建立的应变软... 为了更加真实地反映岩土体材料的特性,以某深基坑土钉加固工程为背景,建立相应的应变软化模型。分析土钉加固基坑过程中,基坑的变形和塑性区分布情况,以及不同位置和不同开挖过程中土钉的应力变化情况。结果表明:用FLAC3D建立的应变软化模型,能够较好地反映土的特性;该准则下,基坑的变形和破坏形式符合实际情况。土钉在加固过程中,轴力变化呈现非线性特征,FLAC3D能够较好地进行反映,能为工程实践提供指导。 展开更多
关键词 应变软化模型 FLAC3D 变形 应力变化 塑性区
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运输应激对山羊心的病理损伤及HSP27、HSP70和HSP90表达的影响 被引量:6
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作者 郑文亚 张雯苑 +4 位作者 刘犇 杨雪 肖鹏 王安平 崔燕 《畜牧兽医学报》 CAS CSCD 北大核心 2019年第10期2129-2138,共10页
运用HE染色法、透射电镜技术、免疫组织化学、免疫印迹和ELISA等方法,探讨不同运输时间对山羊(Capra hircus)心的病理损伤及对热休克蛋白表达的影响,分析公路运输应激2、6 h条件下山羊心的显微结构、超微结构及HSP27、HSP70、HSP90的定... 运用HE染色法、透射电镜技术、免疫组织化学、免疫印迹和ELISA等方法,探讨不同运输时间对山羊(Capra hircus)心的病理损伤及对热休克蛋白表达的影响,分析公路运输应激2、6 h条件下山羊心的显微结构、超微结构及HSP27、HSP70、HSP90的定位和表达量的变化情况。结果表明运输应激组山羊心肌纤维有程度不一的弥漫性颗粒变性,细胞内线粒体肿胀、破裂,间质水肿、出血、炎性细胞浸润,毛细血管扩张、充血,运输6 h组的病变更严重。HSP27、HSP70、HSP90主要在心肌细胞的细胞质中表达,HSP27和HSP90在细胞核中也有表达,三种蛋白在不同区域的心肌纤维和心肌细胞中分布不均。与对照组相比,运输应激2 h组山羊心HSP27蛋白表达量显著升高,运输应激6 h组HSP27表达量下降;与对照组相比,运输应激2和6 h组HSP70、HSP90蛋白表达量均显著或极显著升高。总之,运输应激山羊心组织细胞发生了病理损伤,心肌细胞急性变性十分明显,运输应激6 h组心肌细胞变性更严重,运输后HSP27、HSP70和HSP90蛋白表达量发生了明显变化,与心的应激损伤存在一定的关联。 展开更多
关键词 山羊 病理变化 热休克蛋白 运输应激
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Formation Mechanisms of Some Features in Siliceous Upper Cretaceous-Lower Tertiary Beds of Jordan-Undulations, Geodes, Boudinages
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作者 Elias Salameh Hani Khoury 《Open Journal of Geology》 CAS 2024年第4期569-577,共9页
Geode, boudinage, and undulation structures are widely distributed in the siliceous beds of the Upper Cretaceous/Tertiary rocks in Jordan. Their formation was attributed to tectonic forces, syngenetic processes, organ... Geode, boudinage, and undulation structures are widely distributed in the siliceous beds of the Upper Cretaceous/Tertiary rocks in Jordan. Their formation was attributed to tectonic forces, syngenetic processes, organic disintegration processes, subaquatic gliding, compaction and settlement, and meteoritic impacts. In this work, the structural features in the siliceous beds of Jordan are attributed to an interplay of load and directed pressures, and mineralogical transformation processes (opal-A to opal-CT to quartz), governed by pH changes. Tectonic directed pressure was acting in an ESE-WSW direction and is common in the silicified limestone of Upper Cretaceous. 展开更多
关键词 UNDULATIONS Geodes Boudinages Opal-A Porcelanite Chert Transformations pH changes stress Fields JORDAN
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渗透胁迫下小麦种子萌发成苗与蛋白质变化的关系 被引量:5
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作者 路苹 汪沛洪 《北京农学院学报》 1996年第1期22-27,共6页
小麦种子在渗透胁迫条件下萌发时,其种子蛋白质变化与萌发成苗密切相关。种子萌发初始时间推迟,萌发率下降,种苗生长缓慢,是渗透胁迫抑制种子萌发成苗的直观表现。而种子胚乳清蛋白积累少,导致胚乳贮藏蛋白降解慢和种胚中蛋白质各... 小麦种子在渗透胁迫条件下萌发时,其种子蛋白质变化与萌发成苗密切相关。种子萌发初始时间推迟,萌发率下降,种苗生长缓慢,是渗透胁迫抑制种子萌发成苗的直观表现。而种子胚乳清蛋白积累少,导致胚乳贮藏蛋白降解慢和种胚中蛋白质各组分含量低,则是渗透胁迫抑制种子萌发成苗的内在主要因素之一。 展开更多
关键词 小麦 种子 渗透胁迫 萌发成苗 蛋白质
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Metabolomic changes in children with autism 被引量:1
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作者 Mohammed Al-Beltagi Nermin Kamal Saeed +1 位作者 Adel Salah Bediwy Reem Elbeltagi 《World Journal of Clinical Pediatrics》 2024年第2期171-197,共27页
BACKGROUND Autism spectrum disorder(ASD)is a neurodevelopmental condition characterized by deficits in social communication and repetitive behaviors.Metabolomic profiling has emerged as a valuable tool for understandi... BACKGROUND Autism spectrum disorder(ASD)is a neurodevelopmental condition characterized by deficits in social communication and repetitive behaviors.Metabolomic profiling has emerged as a valuable tool for understanding the underlying metabolic dysregulations associated with ASD.AIM To comprehensively explore metabolomic changes in children with ASD,integrating findings from various research articles,reviews,systematic reviews,meta-analyses,case reports,editorials,and a book chapter.METHODS A systematic search was conducted in electronic databases,including PubMed,PubMed Central,Cochrane Library,Embase,Web of Science,CINAHL,Scopus,LISA,and NLM catalog up until January 2024.Inclusion criteria encompassed research articles(83),review articles(145),meta-analyses(6),systematic reviews(6),case reports(2),editorials(2),and a book chapter(1)related to metabolomic changes in children with ASD.Exclusion criteria were applied to ensure the relevance and quality of included studies.RESULTS The systematic review identified specific metabolites and metabolic pathways showing consistent differences in children with ASD compared to typically developing individuals.These metabolic biomarkers may serve as objective measures to support clinical assessments,improve diagnostic accuracy,and inform personalized treatment approaches.Metabolomic profiling also offers insights into the metabolic alterations associated with comorbid conditions commonly observed in individuals with ASD.CONCLUSION Integration of metabolomic changes in children with ASD holds promise for enhancing diagnostic accuracy,guiding personalized treatment approaches,monitoring treatment response,and improving outcomes.Further research is needed to validate findings,establish standardized protocols,and overcome technical challenges in metabolomic analysis.By advancing our understanding of metabolic dysregulations in ASD,clinicians can improve the lives of affected individuals and their families. 展开更多
关键词 Autism spectrum disorder Metabolic dysregulations Metabolomic changes CHILDREN Mitochondrial dysfunction Oxidative stress Amino acids
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煤层赋存状态突变对动力灾害的影响 被引量:5
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作者 齐黎明 陈学习 薛俊华 《煤炭工程》 北大核心 2012年第12期92-94,共3页
动力灾害严重威胁着矿井安全生产,它的发生与煤层应力关系密切。文章采用数值模拟手段对三种不同煤层赋存状态突变条件下的应力分布状况进行了分析。结果显示,如果煤层赋存状态突变,则应力集中;并且,当煤层倾角和厚度同时变化时,集中程... 动力灾害严重威胁着矿井安全生产,它的发生与煤层应力关系密切。文章采用数值模拟手段对三种不同煤层赋存状态突变条件下的应力分布状况进行了分析。结果显示,如果煤层赋存状态突变,则应力集中;并且,当煤层倾角和厚度同时变化时,集中程度更加剧烈,可为煤岩动力灾害的发生创造非常有利的条件。 展开更多
关键词 煤层赋存 动力灾害 突变 煤层应力
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七氟醚联合瑞芬太尼对腹腔镜子宫切除术患者血流动力学及应激反应的影响
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作者 韩杰 朱敏 汪增洲 《当代医学》 2024年第9期140-143,共4页
目的探讨七氟醚联合瑞芬太尼对腹腔镜子宫切除术患者血流动力学及应激反应的影响。方法选取2019年1月至2022年5月于上饶市妇幼保健院行腹腔镜子宫切除术的82例患者作为研究对象,根据随机抽签法分为对照组与观察组,每组41例。对照组给予... 目的探讨七氟醚联合瑞芬太尼对腹腔镜子宫切除术患者血流动力学及应激反应的影响。方法选取2019年1月至2022年5月于上饶市妇幼保健院行腹腔镜子宫切除术的82例患者作为研究对象,根据随机抽签法分为对照组与观察组,每组41例。对照组给予丙泊酚联合舒芬太尼麻醉,观察组给予七氟醚联合瑞芬太尼麻醉,比较两组血流动力学变化、应激反应、麻醉不良反应发生情况及麻醉后恢复情况。结果气腹后10min,两组心率(HR)均慢于麻醉前,两组平均动脉压(MAP)及观察组血氧饱和度(SpO_(2))均高于麻醉前,对照组SpO_(2)低于麻醉前,且观察组HR慢于对照组,MAP低于对照组,SpO_(2)高于对照组,差异有统计学意义(P<0.05)。气腹后10min,两组皮质醇(COR)、去甲肾上腺素(NE)水平均高于麻醉前,但观察组低于对照组,差异有统计学意义(P<0.05)。观察组不良反应发生率为4.88%,低于对照组的19.51%,差异有统计学意义(P<0.05)。观察组苏醒时间、恢复自主呼吸时间、拔管时间均短于对照组,差异有统计学意义(P<0.05)。结论七氟醚联合瑞芬太尼维持腹腔镜子宫切除手术患者稳定的血流动力学变化,减轻应激反应,减少麻醉后不良反应,保证患者麻醉安全,恢复情况良好,值得临床优先选择。 展开更多
关键词 腹腔镜子宫切除术 七氟醚 瑞芬太尼 血流动力学变化 应激反应
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枇杷7个脱水素基因表达差异分析 被引量:4
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作者 徐红霞 李晓颖 +2 位作者 陈俊伟 冯健君 徐昌杰 《园艺学报》 CAS CSCD 北大核心 2014年第8期1554-1562,共9页
为进一步明确枇杷(Eriobotrya japonica Lindl.)中不同脱水素基因家族成员(EjDHN)的功能和响应机制,以白沙枇杷品种‘宁海白’为试材,分析了7个EjDHN基因在不同器官、果实发育期及ABA和干旱胁迫条件下的表达模式。结果表明,EjDHN5在各... 为进一步明确枇杷(Eriobotrya japonica Lindl.)中不同脱水素基因家族成员(EjDHN)的功能和响应机制,以白沙枇杷品种‘宁海白’为试材,分析了7个EjDHN基因在不同器官、果实发育期及ABA和干旱胁迫条件下的表达模式。结果表明,EjDHN5在各器官中表达量都比较高,EjDHN4主要在花中表达,EjDHN2、EjDHN3、EjDHN6和EjDHN7主要在茎中表达。在果实发育过程中,除EjDHN3外,其他家族成员均与种子发育有关;而EjDHN2和EjDHN5在果肉中表达量较高且与果肉发育有关。7个EjDHN基因在枇杷叶片中的季节性表达变化趋势基本一致,均在冬季表达量最高,而EjDHN1、EjDHN2、EjDHN4和EjDHN5在初夏也有较高的表达量。在干旱胁迫后,叶片中7个EjDHN基因的表达均出现显著增强趋势,其中EjDHN6增幅最大。各基因对ABA处理也有不同响应,以EjDHN6最为敏感。 展开更多
关键词 枇杷 脱水素 基因表达 果实发育期 季节性变化 干旱胁迫 ABA
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重型β地中海贫血眼部变化的研究现状
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作者 魏永灿 陈丹娜 +2 位作者 李雯文 仝娅妮 赵桂玲 《国际眼科杂志》 CAS 2024年第4期601-606,共6页
重型β地中海贫血(β-TM)是一种由珠蛋白合成缺陷引起的遗传性疾病。该病需要长期输血和服用祛铁剂药物治疗,可引起眼部组织的各种继发性变化。与正常同龄人相比,β-TM患者的眼部表现为角膜曲率更为陡峭、前房更浅、晶状体厚度增加、眼... 重型β地中海贫血(β-TM)是一种由珠蛋白合成缺陷引起的遗传性疾病。该病需要长期输血和服用祛铁剂药物治疗,可引起眼部组织的各种继发性变化。与正常同龄人相比,β-TM患者的眼部表现为角膜曲率更为陡峭、前房更浅、晶状体厚度增加、眼轴更短和泪液分泌减少等改变;同时,营养缺乏和使用铁螯合剂药物治疗会增加罹患并发性白内障及视网膜变性的风险,从而影响β-TM患者的生存质量。本文结合国内外相关文献,对β-TM患者眼部相关变化进行探讨和综述,旨在为临床实践提供有价值的见解。 展开更多
关键词 重型Β地中海贫血 眼部变化 输血 铁螯合剂 氧化应激
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Protein changes in rice seedlings during the enhancement of chilling resistance by different stress pretreatment 被引量:4
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作者 ZENG Shaoxi ,WANG Yirou , and LI Meiru, South China Inst of Botany, China Acdemia, Guangzhou 510650, China 《Chinese Rice Research Newsletter》 1997年第3期11-12,共2页
The changes of proteins in the rice (Oryzasativa L.) Tesanai 2 seedling under salt (NaCl,4 g/L), heat shock (42℃, 3h ), and cold(14℃, 3d ) pretreatments were compared toexplore the mechanism of the cross adaptation... The changes of proteins in the rice (Oryzasativa L.) Tesanai 2 seedling under salt (NaCl,4 g/L), heat shock (42℃, 3h ), and cold(14℃, 3d ) pretreatments were compared toexplore the mechanism of the cross adaptationto different environmental stresses. The chill-ing resistance of rice seedling after 1℃, 150pmol·msPFD(photo flux density) for 2d was enhanced distinctly by salt, heat shock, 展开更多
关键词 Protein changes in rice seedlings during the enhancement of chilling resistance by different stress pretreatment
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Volumetric changes in the focal areas of seismic events corresponding to destress blasting 被引量:2
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作者 P.Konicek J.Schreiber L.Nazarova 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2019年第4期541-547,共7页
The typical development of total volumetric change in the focal areas of seismic events,corresponding to destress blasting,is characterized as an explosive phase followed by an implosive phase and with alternating add... The typical development of total volumetric change in the focal areas of seismic events,corresponding to destress blasting,is characterized as an explosive phase followed by an implosive phase and with alternating additional phases following on from that.In a few cases,a non-typical development of volumetric change was identified,where the first phase was implosive and the second phase,explosive.This development is mainly typical for induced seismic events recorded during mining,not for destress blasting.Seismic events were recorded during longwall mining in the Czech part of the Upper Silesian Coal Basin,where the destress blasting technique is used as a rockburst prevention active measure.Kinematic source processes in the focal areas of selected seismic events were analyzed by the seismic moment tensor inversion method,as well as by studying geomechanical rock mass conditions at the localities of the seismic events.The main goal of the analysis was to attempt to identify the reasons for non-typical development of volumetric changes in these cases.Volumetric changes were analyzed for seismic events with energy greater than 104 J,recorded in the period of time from 1993 to 2009(1109 events).80%(891)of the recorded seismic events were induced seismic events that were registered during longwall mining and 20%(218)corresponded to destress blasting events.Research shows that the main reason for the non-typical development of volumetric changes in the focal areas of seismic events is an association with destress blasting in the rock mass,which is very close to rock mass overstressing.The detonation of explosives in boreholes,which would dominate the first phase of volumetric changes,probably obscured stress release in the rock mass,as manifested in the first implosion phase of the volumetric changes in this case. 展开更多
关键词 Destress BLASTING SEISMIC event VOLUMETRIC changes stress release
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Arbuscular mycorrhizal fungi for salinity stress: Anti-stress role and mechanisms 被引量:2
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作者 Muzafar HDAR Syed MRAZVI +3 位作者 Narender SINGH Ahmad MUSHTAQ Shahnawaz DAR Shabber HUSSAIN 《Pedosphere》 SCIE CAS CSCD 2023年第1期212-224,共13页
Salinity stress is considered one of the most harmful environmental plant stresses,as it reduces irrigated land crop production by over 20%worldwide.Hence,it is imperative to develop salt-tolerant crops in addition to... Salinity stress is considered one of the most harmful environmental plant stresses,as it reduces irrigated land crop production by over 20%worldwide.Hence,it is imperative to develop salt-tolerant crops in addition to understanding various mechanisms enabling plant growth under saline stress conditions.Recently,a novel biological approach that aims to address salinity stress has gained momentum,which involves the use of arbuscular mycorrhizal(AM)fungi in plant-microbe interactions.It has been observed that most terrestrial plant root systems are colonized by AM fungi,which modulate plant growth in multiple ways.In such interactions,AM fungi obtain organic compounds from the host plant while providing mineral nutrients,including nitrogen,phosphorus,potassium,calcium,and sulfur,to the host plant.Over recent decades,our understanding of the multifunctional roles played by AM fungi has been broadened and advanced,particularly regarding the mediation of mineral nutrients and the alleviation of stress(especially salt stress)in most crop plants.Increased uptake of phosphorus and augmented tolerance to salinity result in enhanced plant growth and yield.The evident anti-stress role of AM fungi and related mechanisms have been described separately,though they need to be analyzed and discussed together.Therefore,the present review addresses the major role of AM fungi in mitigating salt stress and their beneficial effects on plant growth and productivity.The mechanisms employed by AM fungi to amplify the salt tolerance of host plants by increased nutrient accession(e.g.,phosphorus,nitrogen,and calcium),physiological changes(e.g.,photosynthetic efficiency,cell membrane permeability,water status,and nitrogen fixation),and biochemical changes(e.g.,the accumulation of different osmolytes such as proline and soluble sugars)are also discussed.Furthermore,this review highlights the role of AM fungi in the Na+/H+antiporters.In plants,AM fungi inoculation increases the activities of multiple antioxidant enzymes,including superoxide d 展开更多
关键词 biochemical and physiological changes OSMOLYTES plant-microbe interaction salt stress sodium accumulation
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Effects of osmotic stress on the expression profiling of aquaporin genes in the roughskin sculpin(Trachidermus fasciatus) 被引量:3
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作者 Qian Ma Xinfu Liu +2 位作者 Ang Li Shufang Liu Zhimeng Zhuang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第6期19-25,共7页
Aquaporins(AQPs)are a family of integral membrane proteins that have been shown to be important for osmoregulation in many vertebrates.To identify potential stress resistance-related aqp genes in salinity adaptation o... Aquaporins(AQPs)are a family of integral membrane proteins that have been shown to be important for osmoregulation in many vertebrates.To identify potential stress resistance-related aqp genes in salinity adaptation of the roughskin sculpin Trachidermus fasciatus,we investigated the time-course expression dynamics of seven aquaporin genes(aqp1,4,7,8,10,11 and 12)in three osmoregulatory tissues(kidney,gill and intestine)and one metabolic tissue(liver).The fish were subjected to two different acute osmotic treatments(seawater-tofreshwater transfer respectively achieved in 1 h and 24 h,namely,E-acute and acute group).The expression profiling of the seven aqp genes were performed using quantitative real-time PCR(qRT-PCR).At the time of all sampling time points(0 h,12 h,24 h and 48 h),no expression of aqp4 was found in the gill,liver and intestine;no expression of aqp7 was found in the gill and liver.Significant differences of aqp expression were determined in the four target tissues,and the mRNA levels were largely variable among gene members and tissues.Similar patterns of the time-course expression were detected in most of the aqp genes in T.fasciatus between the two acute groups,except that only one gene(aqp12)in the kidney and three genes(aqp7,aqp8 and aqp10)in the intestine revealed different expression patterns.These results suggest that the expression response of aqp genes was similar under osmotic changes with different rates. 展开更多
关键词 Trachidermus fasciatus AQUAPORIN salinity changes stress response gene expression
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