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101.
102.
芽孢杆菌是植物病害生物防治中重要的生防细菌。采用浊度测定法研究了生防细菌——枯草芽孢杆菌、解淀粉芽孢杆菌及多粘芽孢杆菌对烤烟专用复合肥[m(N)∶m(P2O5)∶m(K2O)=10∶10∶25]、生石灰、甲霜灵、代森锰锌及硫酸链霉素5种烟草生产上常用化学品的敏感性。结果表明:甲霜灵对3种芽孢杆菌的生长无影响,而烤烟专用复合肥和生石灰对3种生防细菌均有一定的促生长作用;而代森锰锌和硫酸链霉素能显著抑制枯草芽孢杆菌、解淀粉芽孢杆菌和多粘芽孢杆菌的生长,其EC50值分别为14.15、11.88、11.30μg/mL和5.20、5.69和2.64μg/mL。 相似文献
103.
探讨了阿莫西林与硫酸粘菌素对猪鸡的大肠杆菌和沙门氏菌的联合抗菌效果。采用微量稀释法分别测定阿莫西林与硫酸粘菌素单药对大肠杆菌和沙门氏菌的最低抑菌浓度(MIC),采用棋盘稀释法测定阿莫西林与硫酸粘菌素联用对大肠杆菌和沙门氏菌的MIC并计算联合指数(FIC)。试验结果显示,对14株试验菌株体外联合抗菌呈协同与相加作用的占78.6%,呈无关作用的占21.4%,无拮抗作用,表明阿莫西林和硫酸粘菌素可联合应用于治疗猪鸡大肠杆菌和沙门氏菌感染。 相似文献
104.
Microstructure and macro performance of Ultra Low Ion Permeability Cementitious Materials (ULIPCM) were investigated by Micro hardness, MIP and SEM EDXA. It was shown that the compressive strength of ULIPCM was more than 80 MPa, flexural strength was more than 11.0 MPa, and elastic modulus was in the range of 38.0 to 42.0 GPa at the age of 28 days; chloride diffusion coefficient was lower than 0.8×10-13m2·s-1, conductive charge for 6 hours was lower than 300 coulombs; sulfate attack resistance was good; shrinkage at the age of 28 days was lower than 400×10-6. Compared with ordinary concrete with which thickness of interfacial transition zone is 60 to 100 μm, the thickness of interfacial transition zone of ULIPCM was lower than 30 μm. Penetration paths of corrosive medium were effectively interrupted in ULIPCM. And pore structure parameters, such as porosity and the most probable pore radius of ULIPCM, were also obviously optimized in ULIPCM. Besides, few CH crystals were in the ULIPCM aggregate and the interfacial transition zone of ULIPCM. And the orientation of CH crystals was poor. 相似文献
105.
106.
Chalinulasterol (1) a new chlorinated sterol disulfate was isolated from the Caribbean sponge Chalinula molitba. Its structure was elucidated using mass spectrometry and NMR experiments. The possible role of chalinulasterol as modulator of the PXR nuclear receptor was investigated but, in spite of the close structural relationship with the PXR agonist solomonsterol A (2), it showed no activity. The structural requirements for the PXR nuclear receptor activity were discussed. 相似文献
107.
Fucosylated chondroitin sulfate (FuCS), a kind of complex glycosaminoglycan from sea cucumber, has potent anticoagulant activity. In order to understand the relationship between structures and activity, the depolymerized FuCS (dFuCS) was chosen to prepare its derivates by selective substitution at OH groups. Its O-acylation was carried out in a homogeneous way using carboxylic acid anhydrides. The structures of O-acylated derivatives were characterized by NMR. The results indicated that the 4-O-sulfated fucose residues may be easier to be acylated than the other ones in the sulfated fucose branches. But the O-acylation was always accompanied by the β-elimination, and the degree of elimination was higher as that of acylation was higher. The results of clotting assay indicated that the effect of partial O-acylation of the dFuCS on their anticoagulant potency was not significant and the O-acylation of 2-OH groups of 4-O-sulfated fucose units did not affect the anticoagulant activity. 相似文献
108.
钾素对马铃薯的生长发育、结薯、薯块膨大和干物质的积累具有十分重要的作用。凉山州马铃薯主产区土壤普遍缺钾少磷,试验选用马铃薯品种凉薯97,研究在凉山州不同地区不同海拔高度施用硫酸钾对马铃薯生物性状的影响,结果表明:马铃薯施用一定量的硫酸钾能适当延长生育期、显著增产、增加薯块干物质和淀粉含量。667 m2施用硫酸钾15 kg的平均全生育期比对照增加2 d;667 m2施用硫酸钾10 kg的平均产量最高,达到1 819 kg,较对照高28.26%,差异达极显著水平;施用硫酸钾对提高干物质、淀粉含量有一定的作用,综合考虑产量、品质、效益等因素,667 m2硫酸钾施用量以5.0~10.0 kg为宜。 相似文献
109.
通过静态单因子急性毒性试验,表明硫酸铜对泥鳅水花和夏花苗种的24,48,96 h的半致死浓度(LC50)分别为0.702,0.587,0.509 mg/L和1.810,1.412,1.270 mg/L,安全浓度分别为0.05,0.13 mg/L;硫酸亚铁对泥鳅水花和夏花苗种的24,48,96 h的半致死浓度(LC50)分别为12.472,9.819,8.297 mg/L和24.876,19.024,16.833 mg/L,安全浓度分别为0.83,1.68 mg/L;戊二醛对泥鳅水花和夏花苗种的24,48,96 h的半致死浓度(LC50)分别为13.286,13.264,12.319 mg/L和45.101,42.701,40.547 mg/L,安全浓度分别为1.23,4.05 mg/L;氧化钙对泥鳅水花和夏花苗种的24,48,96 h的半致死浓度(LC50)分别为102.609,102.299,98.815 mg/L和119.345,117.288,114.305 mg/L,安全浓度分别为9.88,11.43 mg/L。在泥鳅苗种阶段,药物敏感性由大到小依次为硫酸铜、硫酸亚铁、戊二醛、氧化钙。 相似文献
110.