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991.
992.
化学发光免疫分析与酶联免疫分析法检测水产品药物残留的比较研究 总被引:1,自引:0,他引:1
对检测水产品中呋喃唑酮代谢物( AOZ)和氯霉素( CAP)药物残留的两种方法---化学发光免疫分析( CLEIA)和酶联免疫分析( ELISA)法进行了比较研究。结果表明:两种药物残留检测中, CLEIA分析方法的线性范围和检出限均优于ELISA法,且两种免疫分析法的添加回收率均具有很好的相关性;用CLEIA法检测AOZ的检出限为0.01μg/kg,线性范围为0.01~2.56μg/kg,检测CAP的检出限为0.016μg/kg,线性范围为0.025~6.400μg/kg;用ELISA法检测AOZ的检出限为0.1μg/kg,线性范围为0.10~1.62μg/kg,检测CAP的检出限为0.05μg/kg,线性范围为0.05~4.05μg/kg;用CLEIA法检测CAP的批内变异系数( RSD)为5.5%~11.3%,批间RSD为12.3%~20.9%,检测AOZ的批内RSD为6.6%~11.1%,批间RSD为15.6%~18.3%。研究表明,用CLEIA法检测水产品药物残留较ELISA法检出限低、线性范围宽,虽然检出CAP和AOZ的变异系数均高于ELISA法,但仍符合《兽药残留酶联免疫试剂(盒)备案参考评判标准》的规定。 相似文献
993.
Anne C Teilmann Otto Kalliokoski Kirsten R Jacobsen Jann Hau Klas SP Abelson 《Acta veterinaria Scandinavica》2014,56(1):33
Background
Studies have reported that heparin may be unsuitable as an anticoagulant in human plasma samples when quantifying cytokines using multiplex bead array assays. For mouse samples, multiplex assays have been validated for serum and EDTA-plasma, but it remains to be elucidated whether heparin influences the quantification of cytokines, and if so – to what extent. Furthermore, laboratory mice are often anesthetized for blood sampling, which causes acute stress that may influence circulating cytokine concentrations and thus bias experimental results. The objectives of the present study were to identify whether specific cytokine concentrations varied between heparin-plasma, serum, and EDTA-plasma, and whether short isoflurane anesthesia would influence the concentrations of these cytokines in the circulation. Twenty-three acute phase and pro-inflammatory cytokines were quantified in matched serum, EDTA-plasma, and heparin-plasma samples from anesthetized and unanesthetized male NMRI mice using a multiplex assay. In addition, samples from unanesthetized mice were spiked with three levels of heparin.Results
The concentrations of five out of 23 cytokines were significantly different between sample types, but only one cytokine (IL-17A) differed between heparin-plasma and serum. When further spiking the heparin-plasma with increasing concentrations of heparin, there was a significant effect on 11 cytokines, where the cytokine recovery could be correlated to the heparin concentration for ten of these cytokines. Anesthesia resulted in lower concentrations of G-CSF, but had no significant impact on the concentrations of the other 22 cytokines.Conclusion
In mice, heparin seems like a suitable anticoagulant for obtaining plasma for multiplex assays for the cytokines IL-1α, IL-1β, IL-2, IL-6, IL-9, IL-12p40, IL-12p70, IL-13, G-CSF, GM-CSF, IFN-γ, KC, MCP-1, MIP-1α, MIP-1β, RANTES and TNFα, but an effect of heparin in high concentrations should be considered for the cytokines IL-9, IL-12p40, IL-12p70, KC, MCP-1, MIP-1β and RANTES. Short isoflurane anesthesia had significant impact on G-CSF, but none of the other cytokines. 相似文献994.
河川沙塘鳢卵母细胞发育过程中卵黄脂磷蛋白的变化 总被引:1,自引:0,他引:1
采用酶联免疫检测和免疫印迹技术研究河川沙塘鳢卵巢发育过程中的卵黄磷脂蛋白结构和含量变化情况。河川沙塘鳢卵黄磷脂蛋白的分子量为440 kD,免疫印迹结果显示其由3个亚集团组成,分子量分别为95-105 kDa、41.3 kDa和30.7 kDa。7-9月卵巢中不含卵黄脂磷蛋白,10月起开始累积,翌年3月达到最高值,4-5月仍保持在较高水平,其后显著降低,水溶性总蛋白年变化周期也表现出相似的趋势,但是在7-9月有一个的基本量。试验结果表明,河川沙塘鳢卵巢在10月已经开始发育,比形态观察结果提前10个月。雌性河川沙塘鳢在10月起开始启动水溶性蛋白质特别是卵黄磷脂蛋白的合成,并逐渐累积至翌年3月,3月起开始进入繁殖期,4-5月为产卵高峰期。 相似文献
995.
Thomas Kosmehl Falk Krebs Werner Manz Thomas Braunbeck Henner Hollert 《Journal of Soils and Sediments》2007,7(6):377-387
Goals, Scope and Background While water quality strongly improved over decades in the Rhine River, sediments still reflect elapsed contaminations of organic
pollutants and heavy metals. In comparing genotoxic effects induced by both sediment extracts and whole sediments, a ratio
of bioavailable toxicity and total extractable toxicity is obtained. Since contaminated sites whose contaminants are toxic
and as well bioavailable present an elevated risk to the ecosystem, such ratios may be used as a warning signal to identify
sites of primary concern.
Methods Accordingly, two different exposure scenarios were compared to reveal the genotoxic potential of 18 sediment samples derived
from 9 sample sites along the River Rhine. For assessment of effects on genome integrity, DNA fragmentation was measured using
the comet assay with primary cells isolated from zebrafish embryos previously exposed to either organic sediment extracts
or freeze-dried sediments at sublethal concentrations. Additionally, chemical data were used to determine responsible pollutants
and correlate them with biological effects.
Results Whereas 17 out of 18 sediment extracts caused significant DNA damage to the embryo cells, only 4 native sediments showed a
genotoxic potential. Thus, under field-like exposure conditions, a major part of potentially genotoxic compounds seem to remain
particle-bound and ineffective, as shown for whole sediment exposure. Conversely, the organic extracts seem to contain enriched
concentrations even of hardly soluble substances. Hence, organic extracts may be used as a screening tool to address potentially
polluted sites, even though the relevance of these results for the field situation may be questionable. Investigations on
native sediments determined few sites with bioavailable and therefore ecologically most relevant genotoxic sediment compounds.
Discussion However, these results may underestimate the total hazard potential of sample sites with hardly bioavailable substances. Chemical
data revealed a variety of anthropogenic pollutants, ranging from PAHs to heavy metals. Nevertheless, chemical data on the
measured priority pollutants did not fully explain the pollution pattern of the bioassays but clearly determined substances
of concern (e.g., HCB, heavy metals) in particular sample sites.
Conclusions There is a striking advantage in assessing the genotoxicity by means of different exposure scenarios that focus on either
bioavailable or extractable fractions, as the combination of the results allows obtaining information on specific properties
of the genotoxicants and their bioavailability. An additional correlation with chemical data should be required to identify
priority pollutants, as long as the responsible contaminant is known a priori. As many studies revealed inherent failures of such a correlation, an effect-driven analysis of pollutants is recommended
as a promising tool to identify even non-priority pollutants by means of their ecotoxicological effectiveness. 相似文献
996.
997.
建立间接竞争酶联免疫吸附分析方法(idc-ELISA)测定石房蛤毒素(Saxitoxin,STX)。采用碳化二亚胺法,将半抗原STX分别与卵清蛋白(OVA)和牛血清蛋白(BSA)偶联,得到免疫抗原STX-OVA和包被抗原STX-BSA。用STX-OVA免疫BALB/c小鼠制备多克隆抗体。确定的最佳包被抗原质量浓度为2μg/mL,多抗的工作浓度为1∶800,羊抗鼠二抗工作浓度为1∶1 000。回归方程Y=0.136 6X-0.015 1,R2=0.990 1。该方法的灵敏度达到5.8μg/mL,检出范围在0.2~926μg/mL。 相似文献
998.
Kristina Meichner Tracy Stokol Jaime Tarigo Anne Avery Mary J. Burkhard Stefano Comazzi Jonathan Fogle Devorah Marks Stowe Barbara Rütgen Davis Seelig Adi Wasserkrug-Naor William Vernau Dorothee Bienzle 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2020,49(2):249-257
999.
采用黄曲霉毒素时间分辨荧光免疫层析试纸条及配套的时间分辨荧光速测仪,对油料饼粕中黄曲霉毒素B1的快速检测进行了应用研究。该时间分辨荧光免疫分析技术是基于时间分辨荧光免疫层析试纸条和载有Eu(Ⅲ)标记特异性单克隆抗体的样品瓶建立的检测技术。时间分辨荧光速测仪可内置标准曲线,直接输出检测结果。对6种油料饼粕做黄曲霉毒素B1添加回收率实验,回收率在70%~120%之间,批间、批内变异系数<15%。在实际样品的检测中,时间分辨荧光免疫层析试纸条检测技术与液相色谱-串联质谱法相比,检测结果相对误差<15%。时间分辨荧光免疫层析试纸条检测技术测定快速、准确,技术稳定、可靠,设备经济、小型,适用于大批量油料饼粕样品的快速检测和风险评估,具有广阔的应用前景。 相似文献
1000.
基于酶抑制法的农药残留快速检测技术具有简单、快速、易操作、成本低等优点,在基质成分较为简单的蔬菜、水果样品的质量安全快速筛查和监管中发挥了重要作用。然而,在对茶叶样品的检测中,该方法的速测结果普遍呈强(假)阳性,且检测结果与实际农药含量水平无关,严重阻碍了其在茶叶样品检测中的应用。明确茶叶样品中基质对胆碱酯酶干扰的来源、水平与机理是解决这一难题的理论基础。文章综述了茶叶基质成分对胆碱酯酶活性干扰水平的研究进展,同时包含了近年来茶叶功能性成分通过抑制胆碱酯酶活性在阿尔茨海默症(AD)治疗中应用的研究内容。 相似文献