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991.
We studied the accumulation of polycyclic aromatic hydrocarbons (PAHs) and phthalic acid esters (PAEs) in a latosolic red soil and radish (Raphanus sativus) with application of sewage sludge at rates of 10, 20 and 40 g kg(-1) soil or compost at rate of 10 g kg(-1) soil. In radish the concentrations of individual PAHs and PAEs varied from non-detectable to 803 microg kg(-1) dry weight (d.w.) and from non-detectable to 2048 microg kg(-1) d.w., respectively. Compared to the control, higher application rates of sewage sludge resulted in pronounced increases in shoot, root and soil concentrations of PAHs and PAEs. PAE concentrations in radish grown in soil spiked with sludge compost were higher while the PAH concentrations were comparable to those receiving 10 g kg(-1) of sewage sludge. However, the root biomass of radish in soil amended with compost was significantly higher and the shoot-to-root ratio was significantly lower than in the other treatments. The bioconcentration factors (BCFs, the ratio of contaminant concentration in plant tissue to the soil concentration) of di-n-butyl phthalate and di(2-ethylhexyl) phthalate in both shoots and roots and of total PAH concentrations in roots were less than 1.0, but some BCFs for individual PAHs were high with a maximum value of 80. 相似文献
992.
Yang Ping He Yu-quan Zeng Hong Ni Jin-song Yun Qing-jun Huang Xiao-ping Li Shu-mei .Cadiovascular Department China-Japan Union Hospital of Jilin University Changchun P. R. China . Department of Pathdogy School of Basic Medical Sciences of Jilin University Changchun P. R. China . Cardiovascular Department Second Hospital of Jilin University Changchun P. R. China 《仿生工程学报(英文版)》2005,2(2):87-91
1Introduction Congestiveheartfailureisamultipleaetiology,high prevalence,cardiovasculardisorderwithpoorprognosis. Medicaltreatmentofdilatedcardiomyopathyisaimedat alleviatingthesymptomsofheartfailure.Diuretics,ACE inhibitorsandbeta blockershavefavourableeffectson symptoms,exercisecapacityandmortality[1-3].Growth hormone(GH)andinsulin likegrowthfactor(IGF) 1 areinvolvedinseveralphysiologicalprocessessuchas thecontrolofmusclemassandfunction,bodycomposi tionandtheregulationofnutrientmetaboli… 相似文献
993.
Xiaomei Bie Zhaoxin Lu Fengxia Lu Xiaoxiong Zeng 《World journal of microbiology & biotechnology》2005,21(6-7):925-928
Summary The Plackett–Burman screening method was utilized as a tool to evaluate the importance of the selected six factors, including
methanol, ethanol, propanol, butanol, pH and time, which are relevant to the extraction of the antimicrobial substance produced
by Bacillus sp. fmbJ. The main factors that affected the extraction of the antimicrobial substance were determined as methanol (P < 0.0001), ethanol (P < 0.0001), pH (P = 0.0032), and time (P < 0.0001) by using the JMP software. Within the test ranges, methanol, ethanol, and time showed a significant positive relativity
to the total extracted amounts respectively; while pH had a significant negative effect. The maximum prediction profile indicated
that the total extracted amounts for the antimicrobial substance would reach 50.21 mg/100 ml with 99.64% probability. 相似文献
994.
995.
目的探讨超选择子宫动脉栓塞治疗子宫肌瘤的方法及疗效。方法子宫肌瘤65例采用Seldinger技术经皮股动脉插管至双侧髂内动脉,造影了解肿瘤的血供来源后,超选至两侧子宫动脉,缓慢注入平阳霉素碘油乳剂或PVA微粒栓塞治疗。结果患者症状缓解率为93.2%,月经增多,痛经,尿频、尿急,贫血等1-3个月内恢复正常。并发症:除栓塞综合征外,可见阴道不规则流血,腰腿痛,可自行恢复。治疗后3-6个月肌瘤缩小率在30%-68%之间。中短期疗效较稳定,末见复发。治疗前后性激素水平变化无明显差异。结论子宫动脉栓塞术治疗子宫肌瘤操作简单安全,疗效好。超选择子宫动脉插管其分支栓塞,并发症少,具有较大的临床应用价值。 相似文献
996.
研究发光二极管(1ight-emittingdiode,Um)直肠内照射对大鼠实验性溃疡性结肠炎(ulcerative colitis,UC)的抗过氧化损伤以及促进结肠粘膜组织的修复作用。34只大鼠随机分成3组:正常对照组10只、病理模型组12只与病理模型+LED照射治疗组12只.研究中采用乙酸局部刺激复制大鼠UC模型,其中LED治疗组应用LED结肠内照射,1日1次,共10d。其后观察各组的病理变化,血清过氧化损伤水平。结果显示,LED结肠内照射能够促使实验性溃疡性结肠炎的组织修复;显著降低溃疡性结肠炎大鼠血清MDA水平、升高SOD活性。实验表明LED结肠内照射实验性溃疡性结肠炎大鼠具有抗过氧化损伤作用以及促进结肠粘膜组织的修复作用。 相似文献
997.
Mud crabs, Scylla spp. , are commercially important in many Indo-Pacific countries. The larval development of mud crabs has been reported previously as five zoeal and one megalopal stages. This paper reports larval rearing experiments that revealed variability in larval developmental stages in the mud crab Scylla paramamosain, one of four mud crab species. In addition to normal five zoeal stages, an alternative pathway of developing through six zoeal stages was observed for the crab. There were evidences suggested that the appearance of the additional Zoea-VI larvae was associated with unfavourable dietary conditions, including poor quality of diet, inadequate quantity of dietary supply and a period of starvation for newly hatched larvae. Based on exuviae and larval specimens, the morphology of the additional Zoea-VI larvae was described. 相似文献
998.
Tian X.L. Cao L.X. Tan H.M. Zeng Q.G. Jia Y.Y. Han W.Q. Zhou S.N. 《World journal of microbiology & biotechnology》2004,20(3):303-309
The populations of endophytic fungi and actinomycetes from four rice cultivars in the Panyu district (Site 1) and Wushan district
(Site 2) in Guangdong province, South China, were studied. The preponderant endophytic fungi and actinomycetes isolated belonged
to Fusarium and Streptomyces respectively. The incidence of Streptomycetes griseofuscus ranged from 36.1 to 69% out of all the different rice cultivars from the two sites. It is the commonest population of endophytic
actinomycetes, and constituted the greatest part of all the antagonistic communities. The distributions of endophytic fungi
and actinomycetes in roots and leaves were different, endophytic fungi from leaves were diverse, some were organ-specific.
More diverse endophytic actinomycetes were isolated from roots than from leaves. The endophytic fungi isolated from rice in
Site 2 were more diverse than that in Site 1. The diversity of the endophytic actinomycetes, however, was less than that in
Site 1. Acid soil in Site 2 is ideal for the growth and colonization of fungi while the alkaline soil in Site 1 is better
for the growth and colonization of actinomycetes. The results suggested that differences in the chemical composition of soil
could influence the endophytic microbial communities of rice plants. The endophytic fungi and actinomycetes isolated from
poor-growing seedlings and susceptible rice cultivars were more abundant than that the disease-resistant counterparts. In
the dual culture and activity detection of the metabolites, 41.2% of all the isolated endophytic fungi showed antagonism to
rice pathogens. Fifty percent of all the isolated endophytic actinomycetes were antagonistic to those pathogens. The percentage
of Streptomyces griseofuscus and hygroscopicus reached 55.4 and 21.4% of all the active actinomycetes.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
999.
1000.
[目的]利用分子生物学手段探索裳卷蛾变形孢虫的遗传发育地位.[方法]微孢子虫的SSUrRNA序列是构建系统发育进化树的重要工具.试验通过T-A克隆法对裳卷蛾变形孢虫(Vairimorphaceraces)SSU rRNA核心序列进行了克隆,并采用近邻法构建了系统发育进化树.[结果]克隆得到了长为1228bp的核苷酸序列(GenBank EU267796).系统发育分析结果表明:裳卷蛾变形孢虫与分离于小菜蛾(Plutella xylostella)的Vairimorpha sp.Germany(GenBank AF124331)和Vairimorphaimperyecta(GenBank AJ131645)相似性最高,它们在系统发育进化树中与寄主为鳞翅目昆虫的Nosema属聚为一类,与纳卡变形孢虫(Vairimorpha necatrix)为代表的Vairimorpha属为相邻集.[结论]结合其生物学特征,裳卷蛾变形孢虫确实为Vairimorph a属的成员,但根据系统发育分析归入Nosematidae科可能更为合适. 相似文献