Mechanism of exogenous nitric oxide in attenuating endotoxin-induced increase of rat pulmonary microvascular permeability     

LIU Yan-mei  WANG Dian-hua  LING Yi-ling  ZHANG Jun-lan 《园艺学报》2002,18(4):385-388

AIM and METHODS:The animal model of acute lung injury (ALI) caused by intratracheal instillation of lipopolysaccharides(LPS) in vivo and human peripheral blood polymorphonuclear neutrophil (PMN) in vitro were used to study the effects of sodium nitroprusside (SNP), nitric oxide (NO) donor, on LPS-induced PMN accumulation, microvascular permeability and PMN apoptosis. RESULTS:①In vivo, PMN accumulation in lung, the protein content in bronchoalveolar lavage fluid (BALF) and the Evans blue dye and monastral blue dye extravasation in lung tissue of LPS group were markedly higher than those of both sham operation group and LPS+SNP group. ②In vitro, the apoptotic percentage of SNP group was much higher than that of control group, while compared with LPS group, SNP+LPS group has significantly higher apoptotic percentage. CONCLUSIONS:SNP intratracheal instillation attenuated LPS-induced microvascular permeability and alleviated ALI. PMN apoptosis induced by SNP may be one of the potential mechanisms underlying the decrease of PMN accumulation in lung tissue.  相似文献   

雾培法根际CO2对马铃薯生长和光合作用的影响   总被引：13，自引：0，他引：13  

孙周平  李天来  姚莉  邹红藜 《园艺学报》2004,31(1):59-63

通过汽雾栽培方式对马铃薯根际连续 35d的CO2 处理表明 :温室大气处理 (CO2 380～ 92 0 μL·L-1 O2 2 1% )和室外大气处理 (CO2 380 μL·L-1 O2 2 1% )马铃薯植株的形态特征非常接近 ,其株高、叶面积、根系质量、匍匐茎数量、块茎产量以及生物量均比根际高CO2 处理 (CO2 36 0 0 μL·L-1 O2 2 1% )明显提高 ,叶片的气孔导度和胞间CO2 浓度增加 ,光呼吸速率与CO2 补偿点降低 ,叶片光系统Ⅱ功能改善 ,光合速率提高 ,植株生长发育旺盛 ,块茎产量增加 ,说明合适的根际CO2 浓度 (CO2 380～ 92 0 μL·L-1 O22 1% )可能是汽雾栽培马铃薯植株生长旺盛的重要原因  相似文献   

我国北部农牧交错区城郊土地利用时空变化—以包头市为例     

任志远  武永峰 《干旱区资源与环境》2004,(Z2)

以包头市城郊区为例 ,在地理信息系统支持下 ,以乡镇 (苏木 )为研究单元 ,研究本地区土地利用时空动态变化过程 ,并分析其变化驱动因素。从微观角度分析了北方农牧交错区城郊区土地利用变化特征。农牧交错区是人类活动影响强烈之地带 ,土地利用变化与土地持续研究利用 ,对生态安全和地区持续发展具有十分重要的意义。  相似文献   

Angiopoietin-1 and regulation of vascular permeability     

YUE Fei  JIN Hui-ming 《园艺学报》2004,20(10):1929-1932

Angiopoietin-1 (Ang-1) is a newly-found endothelium-specific proangiogenic factor and it had been proved essential roles in both vasculogenesis and angiogensis. Among them, its anti-leakage ability may have great potential applications in clinical treatment of vascular hyper-permeability in a variety of diseases such as cancer, diabetic retinopathy, rheumatoid arthritis, asthma. In this review, some research progresses focused on this aspect are discussed.  相似文献   

内蒙古农牧交错带饲草资源饲用价值评价   总被引：2，自引：0，他引：2  

赵淑芬  王宗礼  孙启忠  闫志坚  李志勇 《中国草地学报》2005,27(3):49-52

对地处内蒙古农牧交错带的林西县饲草资源进行了营养成份分析及饲用价值评价,结果表明:苜蓿粗蛋白质含量高于灌木类及青贮玉米,其营养动态变化规律是随生育期的变化粗蛋白质含量呈下降趋势,粗纤维含量呈上升趋势,各种成份在茎叶中的含量也随生育期变化而变化;灌木类饲用植物粗蛋白质含量15.69%～18.48%,青贮玉米粗蛋白质含量7.64%～11.15%。  相似文献   

pH对洛美沙星与BSA之间结合常数的影响     

刘世旺  徐艳霞  夏小环 《安徽农业科学》2011,39(35):21797-21799

[目的]研究洛美沙星与血清白蛋白之间的作用,了解药物分子在体内的运输和分布情况。[方法]采用毛细管区带电泳法,通过测定在不同pH值、不同牛血清白蛋白浓度的缓冲溶液条件下药物迁移时间的变化,计算出洛美沙星与牛血清白蛋白相互作用的结合常数（Kb）。[结果]pH分别为6.8,7.4和8.0时,洛美沙星与BSA之间的Kb分别为10.185×1045、.319×1045、.356×104 L/mol。[结论]环境pH对洛美沙星与BSA之间的相互作用有强烈影响,当pH处在6.8～7.4之间时,Kb对pH尤为敏感。  相似文献   

The Relationship Between Vegetation Characteristics and Altitudes in Transitional Permafrost Zone in Xidatan,Qinghai-Tibetan Plateau     

Zhiwei WANG  Bentian MO  Leilei DING  Puchang WANG  Qian WANG  Ruixia LU 《农业科学与技术》2016,(6):1462-1467

Many studies showed that permafrost has profound influence on alpine ecosystem. However, former researches were mainly focused on typical points by temporal scales. There were few studies about the correlation between vegetation characteristics and different altitudes covering a large region in spatial pattern, especially in transitional permafrost(TP). There were continuous permafrost(CP) discontinuous permafrost(DCP) and seasonal frozen ground(SFG) in this study region. The types of permafrost changed from SFG to DCP, and finally become CP as the altitudes of Xidatan increase. In this paper, 112 845 points interpreted by HJ1-B(environment and disaster monitoring and prediction small satellite constellation), vegetation investigation points, thawing layer thickness research sites, ground temperature and water content observation plots were used to examine the spatial pattern of vegetation which were located in different altitudes in Xidatan, a typical TP region, in Qinghai-Tibetan Plateau. Vegetation characteristics, soil moisture content(SMC) and thaw depths were collected in 15 August to 25 August2012. Characteristics of vegetation were mainly represented by fractional vegetation cover(FVC) derived from the normalized difference vegetation index(NDVI), as well as above ground biomass(AGB). In this paper, we analyzed that the distinction of vegetation characteristics in each range through statistics data. These ranges were divided by varied altitudes. For examples, the ranges were divided into 50 m or 100 m. In this study we use a large area plots method to further discuss the relationship between the features of vegetation and the different regions of permafrost based on altitudes shifts in Xidatan. A diagram described the vegetation characteristics variability with rising altitudes in transitional permafrost region was drawn in this paper. Our results illustrated the FVCs first increased in SFG region and then decreased in DCP zone slowly, and in CP region FVCs soared then dropped dramatically. With the altitudes increased, the curve of FVCs indicated a parabolic distribution except a little difference in the first 200 m range.  相似文献   

不同沙丘下梭梭(Haloxylon ammodendron)主根周围土壤特征的差异性研究     

马晓飞  楚新正  马倩  靳万贵 《土壤通报》2016,(1):156-163

为探明沙漠建群种植物个体周围土壤养分和盐分空间分布及成因,对艾比湖湖区边缘三种类型沙丘下梭梭主根周围土壤含水量,电导率,全量养分和速效养分的变化进行了研究。结果表明:1固定性沙丘在表层(0~10 cm)处土壤含水量最小,流动性沙丘和半固定性沙丘在浅层(10~20 cm)处最小,以距离主根面3m处表现最为显著(P0.05)。2流动性沙丘和半固定性沙丘土壤有机质和全氮的结构性和空间自相关性均较弱,固定性沙丘养分(全量养分、速效养分)的结构性则较好。3三种沙丘土壤养分的空间分布不均,主要以条状和斑块状分布,整体上呈现出一定的集聚趋势,其中流动性沙丘和固定性沙丘集聚范围在0~2 m圈层,但纵向集聚范围中,流动性沙丘以浅层(10~20 cm),固定性沙丘以较深层(20~40cm)出现集聚,形成"肥岛"。4流动性沙丘土壤电导率对沙丘的影响较其他各特征因子占主导地位,半固定性沙丘和固定性沙丘养分因子占主导地位。  相似文献   

丘陵红黄壤区施用399对“一种两收”再生稻根系和产量的影响     

蔡克桐  沈其文  黄志谋  施仕胜  耿协议 《安徽农业科学》2015,(26):51-52

[目的]研究399对"一种两收"再生稻的影响。[方法]以适宜丘陵红黄壤种植的丰两优香1号、准两优527、宜优673再生稻品种为材料,分别设置喷施399和不喷施399(CK)2种处理,研究各处理对再生稻根系和产量的影响。[结果]结果表明:施用399使水稻在生育期上延缓成熟,且施后再生稻的总根系数量、白根数量、根鲜重、根干重、根体积大幅度增加,同时在两季总产量上准两优527、丰两优香1号和宜优673品种分别比对照增产6.39%、4.86%、5.94%。[结论]施用399有利于准两优527、丰两优香1号和宜优673再生稻品种再生根的发生。  相似文献   

Root zone temperature alters storage root formation and growth of sweetpotato          下载免费PDF全文

P. Taranet  G. Kirchhof  R. Fujinuma  N. Menzies 《Journal of Agronomy and Crop Science》2018,204(3):313-324

Large mounds amended with plant residues are a common cultivation method for sweetpotato (Ipomoea batatas) in the western parts of the Papua New Guinea highlands, with a suggested benefit of elevated root zone temperature (RZT) from decomposition. This study aimed to evaluate whether RZT affects the formation and growth of sweetpotato storage roots. Experiments evaluated the effects of a constant elevated RZT on the Beauregard cultivar and of a short‐term increase in RZT on the Beauregard and Northern Star cultivars. Plants were grown in 18‐L pots divided into a control compartment (constant RZT at 20°C) and a treated compartment (RZT at 30, 40 or 50°C). Constant elevated RZT was maintained until harvest, while short‐term increase in RZT occurred in weeks 2 and 3 only. Constant elevated RZT did not affect the total number of storage roots, but RZT of 30°C and above reduced the dry‐biomass of storage roots. The short‐term increase in RZT did not alter the total number or dry‐biomass of storage roots in Beauregard, while both of these attributes were reduced at RZT of 40°C or above in Northern Star. Elevated RZT inhibited dry‐biomass accumulation of storage root, with a more pronounced impact at constant elevated RZT. These results demonstrate that any benefits of the mound culture on sweetpotato yield production do not arise through the influence of temperature elevation.  相似文献