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121.
WEI GUO ZHI‐YONG WANG YI‐LEI WANG ZI‐PING ZHANG JIAN‐FANG GUI 《Molecular ecology resources》2005,5(2):369-371
Six polymorphic microsatellite markers were isolated and characterized using an enriched library technique in the large yellow croaker (Pseudosciaena crocea Richardson, 1864), a commercially important marine fish in China. They showed PIC (polymorphism information content) ranging from 0.064 to 0.885 (average of 0.580) and allele numbers ranging from two to 13 (average of 7.5), which were useful for the studies on population genetics and selective breeding of the large yellow croaker. 相似文献
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A total of 973 isolates of endophytic fungi were recovered from 1144 tissue fragments of the six me-dicinal plant species belonging to 4 families collected in the Beijing Botanical Garden. Of these isolates 778 sporulated and were identified into 21 taxa by morphological characteristics. Among the taxa 11 belonged to Coelomycetes, 6 to Ascomycetes, and 4 to Hyphomycetes. Various numbers of endophytic fungi (5―8 taxa) were obtained from each plant. Alternaria alternata was the dominant species in the 6 plants, and Microsphaeropsis conielloides was also dominant in Eucommia ulmoides. There were high colonization rates (47.9%―63.1%) and isolation rates (0.7―0.93) of endophytic fungi, and they were conspicuously higher in twigs than those in leaves in the 6 plants examined. The colonization and isolation rates of endophytic fungi increased with the twig age. The results based on the analyses of cluster and Sorenson's similarity coefficients indicated that some endophytic fungi showed a certain degree of host and tissue preference. 相似文献
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125.
Norepinephrine transporter(NET)is expressed in cardiac sympathetic ganglia of adult rat 总被引:19,自引:0,他引:19
LiH MaSK 《Cell research》2001,11(4):317-320
INTRODUCTIONThe sympathetic nervous system (SNS) plays animportant role in regulating cardiac function in bothhealth and disease through releasing neurotransmit-ter norepinephrine (NE). 1n central nervous sys-tem (CNS), the neurotransmission of NE is terminated tbIough reuptaxe of released neurotransndt-ter by Na , Cl---dependent norepineplirine trans-porter (NET) on pre--synaPtic membrane[1, 2]. ALthough the NE uptake was well studied in heaxt, butthe molecular basis fOr that is s… 相似文献
126.
HPLC-ELSD法在刺五加药材糖类成分分析中的应用 总被引:2,自引:2,他引:0
建立一种高效、快速的高效液相色谱—蒸发光散射检测法(HPLC-ELSD)分析刺五加药材中糖类成分—葡萄糖及蔗糖组分。采用CHROMATOREX NH2柱为固定相;以乙腈:水为84.5:15.5(V/V)为流动相,流速1.0 mL·min-1;漂移管温度为100℃;氮气流速为2.5 L·min-1。在上述色谱条件下,葡萄糖和蔗糖的线性范围分别为0.023 2~0.116 0 mg·mL-1及0.099 6~0.496 5 mg·mL-1;且该二种糖的检测限分别(信/噪=3)为3.87 ng和3.31 ng。本方法无须进行糖衍生化而直接用于刺五加药材中糖类成分的分离分析。 相似文献
127.
YING PING WANG DENNIS BALDOCCHI† RAY LEUNING‡ EVA FALGE§ TIMO VESALA¶ 《Global Change Biology》2007,13(3):652-670
Flux measurements from eight global FLUXNET sites were used to estimate parameters in a process‐based, land‐surface model (CSIRO Biosphere Model (CBM), using nonlinear parameter estimation techniques. The parameters examined were the maximum photosynthetic carboxylation rate () the potential photosynthetic electron transport rate (jmax, 25) of the leaf at the top of the canopy, and basal soil respiration (rs, 25), all at a reference temperature of 25°C. Eddy covariance measurements used in the analysis were from four evergreen forests, three deciduous forests and an oak‐grass savanna. Optimal estimates of model parameters were obtained by minimizing the weighted differences between the observed and predicted flux densities of latent heat, sensible heat and net ecosystem CO2 exchange for each year. Values of maximum carboxylation rates obtained from the flux measurements were in good agreement with independent estimates from leaf gas exchange measurements at all evergreen forest sites. A seasonally varying and jmax, 25 in CBM yielded better predictions of net ecosystem CO2 exchange than a constant and jmax, 25 for all three deciduous forests and one savanna site. Differences in the seasonal variation of and jmax, 25 among the three deciduous forests are related to leaf phenology. At the tree‐grass savanna site, seasonal variation of and jmax, 25 was affected by interactions between soil water and temperature, resulting in and jmax, 25 reaching maximal values before the onset of summer drought at canopy scale. Optimizing the photosynthetic parameters in the model allowed CBM to predict quite well the fluxes of water vapor and CO2 but sensible heat fluxes were systematically underestimated by up to 75 W m−2. 相似文献
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129.
一株DDT降解菌的筛选、鉴定及降解特性的初步研究 总被引:2,自引:0,他引:2
从DDT污染的土壤中筛选具有DDT降解能力的细菌,经过富集培养、分离纯化得到56株细菌,将其接种到基础盐酵母培养基,7d后用紫外分光光度计法初筛得到降解率较高的一株菌,编号为D-1.通过16S rDNA序列分析结合传统分类学方法确定该菌为寡养单胞菌属(Stenotrophomonas sp.)的一株茵.对菌体降解DDT的特性的研究表明,在培养温度为3℃,底物质量浓度为40 mg/L, pH 7.0,摇床转速为200 r/min的条件下,该菌株对DDT降解10d的降解率为69.0%. 相似文献
130.
崇明东滩湿地营养盐与重金属的分布与累积 总被引:12,自引:0,他引:12
测定了崇明东滩湿地盐沼植物和沉积物中TN、TP、重金属Cu、Zn、Pb和Cd的含量,阐明了它们在湿地中的分布与累积特征,评估3种盐沼植物对营养盐和重金属的富集能力,并讨论了互花米草入侵对长江口湿地生态系统可能造成的影响.海三棱镳草地上部分的TN、Cu、Pb和Cd的含量均显著高于芦苇和互花米草(p<0.01),而地上部分TP和Zn却表现为:海三棱镳草和互花米草无显著性差异(p>0.05),但均显著高于芦苇(p<0.01).东滩湿地沉积物中TN和重金属的分布与累积特征为:芦苇带>互花米草带>海三棱镳草带>光滩,即随着高程的增加,沉积物中TN和重金属的含量逐步上升;但沉积物中TP含量变化不大,基本维持在0.06%左右.基于盐沼植物地上部分的生物量,估算了3种盐沼植物地上部分的营养盐和重金属库,结果表明:互花米草地上部分的养分库和重金属库均大于芦苇和海三棱镳草,表明收获互花米草对环境的净化效果最佳,特别对磷的去除效率是最高的. 相似文献