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1.
本文通过翻阅文献资料并结合日常的检测实际,分析胶体金免疫层析法快检产品应用于水产品中药物残留的检测时假阳性和假阴性的风险来源及产生的原因,提出相应的建议和应采取的措施,以期提高对水产品中药物残留的快速检测的效果。  相似文献   

2.
基于抗原抗体反应基础上建立的酶联免疫分析法(ELISA),具有操作简单、快速、灵敏度高、特异性强等优点,是目前水产品中氯霉素残留筛选最常用的方法,但在实际操作过程中会发现有假阳性存在.为此,本文分析了ELISA方法检测水产品中氯霉素残留假阳性的原因.  相似文献   

3.
胶体金免疫层析法快速检测水产品中呋喃妥因代谢物残留   总被引:1,自引:0,他引:1  
采用胶体金免疫层析技术(GICA)测定水产品中的呋喃妥因代谢物残留,并用液相色谱-串联质谱(LC-MS/MS)对实验结果进行确证。结果显示,胶体金免疫层析法的检测限为1.0μg/kg,假阳性率不大于5%,假阴性率为0;对实际样本的检测结果与LC-MS/MS法一致。研究表明,胶体金试纸条法操作简便、快速,成本低,为水产品中呋喃妥因代谢物的残留检测提供了快速筛选方法,而LC-MS/MS法灵敏度高,结果准确,适用于阳性样本的确证和精确定量。  相似文献   

4.
针对现有的孔雀石绿免疫胶体金快速检测试剂盒在水产品孔雀石绿和隐性孔雀石绿残留检测中存在前处理复杂、检测时间偏长、灵敏度达不到检测要求等问题。对样品处理中的提取剂、净化剂及胶体金试剂板组分进行了优化。优化后试剂盒的检测时间从40分钟缩短到20分钟之内,检测限从3.0μg/kg降低到2.0μg/kg,检测准确度也提高到假阳性和假阴性率均小于5%。  相似文献   

5.
酶联免疫吸附试验(ELISA)具有操作简便、灵敏度高、样品容量大、仪器化程度和分析成本低的优点,已成为目前水产品药物残留检测中使用最普遍的方法之一,几乎所有重要的水产品药残检测都已建立或试图建立ELISA,如氯霉素、四环素、链霉素、己烯雌酚等.但ELISA也有影响因素较多,易出现假阳性结果等缺点.现将操作过程中需要注意的问题,作如下探讨.  相似文献   

6.
应用胶体金免疫层析法快速检测水产品中残留的氯霉素.实验结果表明,该快检法检出限为0.3μg/kg;方法具有良好的稳定性,假阳性率和假阴性率均为0%;对其他药物无交叉反应,特异性较好;重复性良好,对实际样品采用胶体金免疫层析法和国标方法进行检测,实验结果基本一致.用胶体金免疫层析法检测氯霉素残留具有操作便捷、直观、低成本的特点,可用于水产品的初步筛查.  相似文献   

7.
针对硝基呋喃类代谢物的胶体金免疫层析法(GICA)检测方法存在的缺陷,实验以硝基呋喃类代谢物实际阳性样本和模拟阳性样本为研究对象,选择液相色谱-串联质谱(LC-MS/MS)辅助优化GICA代谢物的水解和衍生条件前处理步骤,建立了一种快速检测水产品中硝基呋喃类代谢物的方法。结果显示最佳实验条件为:盐酸浓度0.35 mol/L,0.05 mol/L 2-硝基苯甲醛0.35 mL,水浴温度90℃,水浴时间120 min。此条件下,胶体金免疫层析法的前处理时间缩短至120 min,检测时间为5 min, 4种硝基呋喃类代谢物的检出限均为0.05μg/kg且重现性好。本方法对140批次不同基质样品进行分析,检测得出12批次阳性样品,假阳性和假阴性率均为0。结果表明本方法在降低实验前处理时间同时,适用于不同的样品基质,可应用于大批量实际样品的测定。[中国渔业质量与标准,2021,11(4):31-38]  相似文献   

8.
重金属能够在水产品中富集,导致水产品大量死亡,有些则会通过食物链进入人的身体,对人的生命安全造成威胁。海洋水产品样品中常见的重金属检测方法有原子光谱法和电化学分析法,另外利用发光细菌检测海洋水产品中的重金属离子近年来也引起广泛的关注。该文通过将不同的海洋水产品中的重金属检测方法进行比较,分析其优缺点,为进行水产品中重金属检测的研究者提供一定理论指导。  相似文献   

9.
当前,国内生产盐酸克伦特罗、莱克多巴胺、沙丁胺醇检测卡(试纸条)的厂家众多,试剂条的质量参差不齐,同一厂家不同批次的产品质量差异很大,致使现场检测过程中,要么假阳性样品数量太多,增加了监管部门确认经费的负担,要么出理假阴性样品,导致兽药残留超标的畜产品流入市场,造成畜产品质量安全隐患。如何在使用前进行质量验证是确保试纸条检测结果准确有效的重要手段。文章探讨了快速检测试纸条的质量验证试验,提出三个验证参数"检测阈值、假阴性率、假阳性率"。指出"检测阈值"是个重要参数。  相似文献   

10.
为应对韩国、日本等国家进口水产品设置的技术性贸易壁垒,促进曹妃甸出口水产品生产企业贸易,对2012至2016年间曹妃甸区出口的水产品中安全风险物质和水生动物疫病监测结果进行分析,显示兽药残留量阳性率为0;重金属检出阳性率基本稳定,检出项目分别为砷、铅、汞、镉、铬、铜;食品添加剂亚硫酸盐检出阳性1例;水生动物疫病未检出阳性。建议今后检验检疫部门加强对出口水产品养殖用水监管。  相似文献   

11.
For the inoculation of the dermatophyte-test-medium Fungassay, 200 skin scrapings from horses, 13 from cattle and 13 from artificially infected guinea pigs were used. As control methods, the alkali method, the fluorescent microscope technique and the usual mycological culture were available. For the analysis of skin scrapings, the Fungassay culture mediums are clearly inferior to the usual mycological culture. Fewer dermatophytes were isolated and false positive as well as false negative results occurred. The cultivation of Trichophyton verrucosum failed on the dermatophyte-test-medium.  相似文献   

12.
Proliferative kidney disease (PKD) is an economically significant disease caused by the myxozoan parasite Tetracapsula bryosalmonae. Polymerase chain reaction (PCR) protocols using primers specific for the small subunit ribosomal RNA (18S rDNA) gene of the parasite enable detection, however, false positive and negative results can render detection inconclusive. In this study a decontamination protocol was developed, using hydroxylamine hydrochloride (H), to prevent false positives by blocking re‐amplification of carry‐over contaminants. A mimic molecule was also developed and used as a competitive internal standard coamplified with target DNA in PCRs, revealing both true and false negatives. The sensitivity of one new and two existing primer sets was assessed with all primers detecting DNA equivalent to at least eight parasite cells per gram of tissue. This improved PCR protocol canprovide more reliable testing for T. bryosalmonae.  相似文献   

13.
虾肝肠胞虫被认为是凡纳滨对虾"长不大"现象的主要病原之一,国内外学者已建立其PCR检测技术,包括18S-PCR、SSU-PCR及SWP-PCR。采集36个凡纳滨对虾苗种样本、5个卤虫样本和12个水样,应用上述3种PCR方法进行检测,并对阳性产物进行克隆测序和序列同源性分析,以比较检测灵敏度和准确性。试验结果显示,18S-PCR在第一步扩增的灵敏度最好,SSU-PCR在第二步扩增的灵敏度显著高于SWP-PCR,但存在着一定的假阳性现象。建议在对凡纳滨对虾苗种进行虾肝肠胞虫的检测时,宜采用灵敏度更高的套式SSU-PCR方法。  相似文献   

14.
Lactococcus garvieae is recognized as an emerging pathogen in fish. Several PCR‐based methods have been developed for the detection and identification of L. garvieae; however, the sensitivity of these methods is still in question regarding the discrimination of this organism from other closely related species. Two primers, ITSLg30F and ITSLg319R, were designed from the sequence in the 16S–23S internal transcribed spacer (ITS) region and used for the specific detection of L. garvieae. L. garvieae strains including fish isolates were positive by this method. In contrast, previously developed PCR methods showed false‐positive results with non‐L. garvieae species. Our results indicate that a PCR method using the newly designed ITS primer set provides a sensitive and efficient tool for the detection of L. garvieae in fish and aquaculture environments.  相似文献   

15.
The Community Action Plan requests EU member states to implement measures that ensure the recovery of the severely depleted European eel stocks. One of the main threats is posed by Anguillid herpesvirus 1 (AngHV‐1) leading to increased mortality in both wild and farmed eels. Following recommendations of the OIE to minimize the risk of obtaining false‐negative results, the main aim of the study was to optimize diagnostic methods for AngHV‐1 detection using conventional PCR, nested PCR and in situ hybridization assay. While 53.3% of the individual organ samples were tested positive for AngHV‐1 by PCR, the additional virus analysis via nested PCR revealed that the actual prevalence was 93.3%. In the cell cultivation passages, a cytopathic effect was hardly found in the first two rounds. In the third passage onto cell cultures, a lytic CPE was detected. The identification and confirmation of the viruses obtained from cell cultures as well as directly from the organ tissues were proceeded by PCR, nested PCR and sequencing of the PCR products. While no positive signal was detectable in the first round by PCR using samples from the third cell culture passages, the nested PCR provided weak but visible positive signals.  相似文献   

16.
根据线粒体控制区序列设计了青鱼(Mylopharyngodon piceus)、草鱼(Ctenopharyngodon idellus)、鲢(Hypophthalmichthys molitrix)、鳙(Aristichthys nobilis)物种特异的PCR引物,通过对四大家鱼受精卵的PCR扩增,种间交叉扩增,相关种类早期资源的扩增以及未知种类鱼卵的鉴定发现,所设计的引物具有很高的种类特异性,对特定种DNA具有良好的扩增效果,但是不能进行交叉扩增,对四大家鱼外的其它种类也不能扩增。实验没有出现一例假阳性或假阴性结果,说明所设计引物的种类特异性高。该方法特别适合从鱼类早期资源大量样本中准确快速鉴定四大家鱼种类。  相似文献   

17.
Infectious salmon anaemia (ISA) is an economically important disease in New Brunswick, Canada. Current regulatory control involves detection of ISAv in broodstock, hatcheries and marine sites through a surveillance program. Prior to recent assessments of operating characteristics of diagnostic tests, the efficiency of this surveillance program was difficult to evaluate. In order to determine the optimal testing strategies for various phases of production, a cost-effectiveness analysis was done for different strategies including single testing and multiple testing with results interpreted in series or in parallel. The lowest cost testing strategy, which would achieve a group-level sensitivity (GSe) of 95% and a group-level specificity (GSp) of 95%, was determined for each production phase. Our analyses showed that the most cost-effective testing strategy depended on the production phase. If sampling is to be carried out in a freshwater facility, then broodstock should be tested by VI alone, while pre-smolts should be tested with IFAT and VI used in series. For fish reared in saltwater, parallel interpretation of results from VI and RT-PCR, or testing with VI alone, are appropriate testing strategies for broodstock. For market-fish, PCR alone is a good screening option. If one assumes the prevalence of ISAv in moribund fish is at least 50%, then a maximum of 5 fish (at a cut-point of 1 positive fish to designate a cage as positive) need to be tested at a cost of $220. If one desired to have a perfect GSp (i.e. no false positive cage designations), serial testing with IFAT and VI is a better option. However, for this strategy a maximum of 9 fish (at a cut-point of 1) need to be tested at a cost of $472.  相似文献   

18.
抑制差减杂交法克隆牙鲆变态早期差异表达的基因   总被引:2,自引:0,他引:2  
为了克隆变态早期牙鲆头部差异表达的基因,采用抑制差减杂交法,以变态前的仔鱼头部表达的RNA作为驱动RNA,建立了牙鲆变态早期的差减cDNA文库,并利用相对定量RT-PCR对其进行了筛选。差减库的平均插入片段558bp左右,阳性率为81.8%。随机测定的45个克隆,在剔除假阳性克隆后,共得到22个不同的基因,其中13个为已知cDNA的同源基因,而另外9个为已知蛋白的同源基因,分别为prolactin receptor-like,COL1A1,M3-muscarinic receptor,Sfrs3,tropomyosin,ribosomal protein L27,ribosomal [rpteom S12,GAPDH,COL1A3。在所有22个基因中,COL1A1基因在差减库中的分布频率最高,为22.2%。RT-PCR检测结果表明,在所检测的11个基因中,所有基因在右眼移动前后的牙鲆头部均有表达,只是体现在表达水平上的不同。  相似文献   

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