黄曲霉素对裸鼹鼠肺泡上皮Ⅱ型细胞基因表达的影响

目的:观察不同浓度黄曲霉素对裸鼹鼠肺泡上皮Ⅱ型细胞(AEC II)相关因子m RNA表达的影响,探讨裸鼹鼠抵御肺癌的分子机制。方法:通过酶消化法分离裸鼹鼠肺组织细胞并用免疫黏附法进行纯化得到裸鼹鼠肺泡上皮Ⅱ型细胞进行原代培养,40小时后,实验组分别给予不同浓度(0.25、0.5、1.0、2.0和4.0 mg/L)的黄曲霉素处理,溶剂对照组给予DMSO(0.4 m L/L)处理。黄曲霉素作用48小时后收集细胞,用实时定量PCR技术检测裸鼹鼠AECII细胞中的SP-C基因及TNF-α、IL-1、IL-6、IL-8、IL-12等炎症因子的m RNA表达变化。结果:原代分离的裸鼹鼠AEC II细胞纯度70%,活性90%,可用于体外实验。定量PCR结果显示黄曲霉素使裸鼹鼠AEC II细胞SP-C表达水平显著下降,TNF-α、IL-1、IL-6、IL-8、IL-12等炎症因子的表达水平在黄曲霉低于2 mg/L浓度的条件下没有显著变化。结论:裸鼹鼠AEC II细胞在黄曲霉素导致细胞受损的情况下,仍然保持较低水平的炎症因子表达,这可能是其抵抗肺癌的机制之一。     

微波生物效应研究的现状及应用

着重介绍了微波对微生物、黄曲霉素、人及动物的生物效应,以及微波在浸取和医学上的应用。     

食品常见真菌毒素的危害及其防止措施

真菌毒素是一类由真菌产生的普遍存在的化合物。危害人类健康的真菌毒素主要源于曲霉Aspergillus、青霉Penicil-lium、麦角菌属Claviceps和镰刀菌Fusarium等产生的次生代谢物。从全球范围来看,粮食安全问题经常是由谷物、坚果、水果和绿色咖啡豆上的真菌毒素造成的。其中,玉米和花生仁中的黄曲霉素经常超过安全阈值。在以这些食物作为主食的地处温暖和潮湿气候国家的消费者特别容易食用到黄曲霉素污染的食物。而真菌毒素往往会引起人类和动物急性中毒、慢性中毒和致癌。其不可避免地、广泛地、持续地影响着全球人类的健康。目前的防止措施包括选用抗真菌植物、采用适当方法贮藏食物以及食用绿色蔬菜等来预防癌症等。本文阐述了食品中常见真菌毒素的污染情况及其毒性,并对常用防止措施进行了综述,以期为食品真菌毒素防控工作提供参考。     

用数量场描述方向敏感感受野

1965年Barlow ＆ Levick及我国科技工作者分别独立提出了原理大致相同的方向检测感受野模型,但其数学模型却一直未见有报道.本文用数量场方法给出了其数学模型,这是一个Gabor函数模型,并据此解释了方向检测感受野的方向调谐曲线以及方向检测通道数量问题.     

生物分子的纳米粒子标记和检测技术

生物分子的标记和检测一直是生物分析领域的重要内容 .近年来 ,纳米材料与生物检测技术的结合 ,使得生物分子的检测有了重要的发展 ,这一交叉学科现已成为生物分析领域最具活力的研究方向 .对近期出现的新型纳米粒子标记物的性质、检测原理、特点和应用进行了评述 ,并分析了用该标记物进行分析的可能发展方向     

基于高通量测序技术的基因组结构变异检测算法

基因组结构变异的检测是生物信息学的重要方向之一.本文分别对基于高通量测序技术的双末端映射方法、映射分布方法、分裂片段方法和序列拼接方法等检测技术的四种算法进行详细的解读和说明,阐述了以上四种方法两两结合的检测算法,并分析了各种检测方法的性能和适用的条件,说明混合结合的方法将会成为未来发展的方向.     

山苍子——一种值得发展的高效经济林木

山苍子主产我国长江流域以南各地,有野生和人工栽培林,具有很高的经济价值。山苍子精渍是合成紫罗兰酮系列高级香料的主要原料,是出口换汇的大宗精油。山苍油同时是食品良好的天然增香剂,并具有防霉和抑制黄曲霉素产生的作用。山苍子在医药、饲料、塑料是油墨等生产中的也都用途。     

食源性病毒核酸恒温检测技术研究进展

食源性病毒已成为全球引发食品安全事件的重要病原,对新型检测技术的不断发展提出了严峻的挑战。早期PCR技术在病原检测领域中的应用,推动了对食源性病毒的全面认识。近年来核酸恒温检测技术发展迅速,包括环介导等温扩增技术、重组酶聚合酶扩增技术、核酸序列依赖性扩增技术、链置换扩增技术、滚环扩增技术等,在抗复杂基质干扰、装备要求低以及可现场实时检测等方面具有明显的技术优势,已成为食源性病毒检测领域的热点研究方向。因此,本文对近年来食源性病毒核酸恒温检测技术的原理、应用、优缺点等方面进行综述,并对未来发展方向进行了展望。     

转基因作物及加工品检测技术概述

随着公众对转基因产品关注度的提高和转基因标识制度的建立,快速、准确、灵敏地检测出转基因成分是客观发展的必然要求,建立高效、高通量的转基因检测技术已成为国内外的热点课题。我们简要介绍了转基因检测技术的概念、原理和研究进展,比较了各种转基因检测技术的优缺点,对转基因检测技术的发展方向进行了总结和展望。     

酸橙过海亦养生

70年代,英国的一个养鸡场里发生了一 件惊人的事:10万多只壮健肥硕的鸡,突然 全部死光。经过调查研究,原来是鸡吃食了已 经发霉了的花生所带来的一场灾难——花生里 含有黄曲霉素,它是一种致癌性很强的毒物。 科学家研究发现,在稻米、麦类、玉米和 花生等发霉的粮油食物中,容易含有黄曲霉 素,它是黄曲霉菌生长时的一种代谢产物,人 和禽畜吃食后,随着消化系统进入人和动物的     

兰花病毒检测技术研究进展(综述)

综述近年来应用于兰花病毒检测的各种技术。较详细地介绍了血清学方法和分子生物学方法的应用情况;简述一些常用检测方法的优缺点,为在兰花生产中建立快速简便的病毒检测技术提供参考。     

胶体金免疫层析试纸条技术在病毒检测领域的应用研究现状北大核心CSCD

胶体金免疫层析试纸条技术是一种快速、灵敏和精准的固相标记检测技术,胶体金免疫层析试纸条具有价格低廉、操作简便、检测快捷和特异性强的优点,具有在短时间内灵敏、准确地定性检测出相关病毒的潜在能力,有效解决传统检测方法在医学、兽医、动植物病毒检测和农药残留检测等领域存在检测时间长、设备不便和专业性强的弊端。目前在检测领域,该技术在检测细菌性疾病、病毒性疾病和预防传染性疾病大面积扩散等方面都有应用,因此,该技术在检验方面具有巨大的发展空间。文中主要对胶体金免疫层析技术进行综述,并对该技术在生物病毒检测方面进行总结和展望。     

用于新型冠状病毒检测的核酸等温扩增技术研究进展

核酸检测作为新型冠状病毒肺炎(COVID-19)筛查诊断和病情监测的主要手段,在疫情防控中发挥了重要作用。虽然实时荧光定量PCR被认为是新型冠状病毒(SARS-CoV-2)核酸检测的金标准,但其依赖荧光定量PCR仪且扩增检测时间较长,难以实现现场快速检测。因此许多基于核酸等温扩增的SARS-CoV-2检测方法相继诞生。等温扩增对仪器温控要求不高,通过与微流控芯片和可视化检测技术结合,可进一步简化操作、降低成本,为SARS-CoV-2现场快速筛查提供有力的技术支撑。本文围绕已报道的SARS-CoV-2等温扩增检测方法原理、检测性能及优缺点进行探讨,为进一步发展SARS-CoV-2现场快速检测平台提供参考。     

3种检测吡咯喹啉醌的方法比较

目的:研究和比较3种检测吡咯喹啉醌(PQQ)的方法,确定各种方法的特点和适用范围。方法:设计和改进了3种检测PQQ的方法,分别为活性电泳法、光谱法和NBT-Gly法,探讨其检测限和线性范围、精密度、样品检测和加样回收率。结果:活性电泳法专一性好,具有很高的灵敏度,可检测到12.6 ng/mL PQQ,可靠但准确性较差;NBT-Gly法操作简便,可用于大量样品的检测,但重复性不佳;光谱法精密度较好,但样品中存在吸光物质时对检测结果影响较大。结论:活性电泳法、光谱法和NBT-Gly法均可用于PQQ的检测,活性电泳法适于培养上清等复杂样品的粗略定量,NBT-Gly法适于大量样品的检测,光谱法适于纯度较高的PQQ的定量。     

A novel homogenous detection method based on the self-assembled DNAzyme labeled DNA probes with SWNT conjugates and its application in detecting pathogen

In this paper, a novel and cost-effective homogeneous detection method was constructed for the detection of genomic DNA and Staphylococcus aureus (S. aureus), based on the noncovalent assembly of DNAzyme-labeled detection probe and single-walled carbon nanotubes (SWNTs). When the target genomic DNA and hemin was existed in the detection solution, the detection probe wrapped on the SWNTs by π-stacking interactions would keep away from SWNTs and form a DNAzyme-self-assembly construction. This DNAzyme construction could catalyze 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS2?) and generate a colored product which could lead to the absorbance changes. Hence, according to its catalyzed capacity, the DNAzyme construction could amplify the detection signal. The concentration of target DNA could be quantified by exploiting their optical absorption changes at 414 nm and the concentration limit of detection of the method was 30 nM. And this detection method detected S. aureus quantitatively. In addition, this work proved that the method obtain higher detection sensitivity compared with the method without SWNTs because of the protection profile of SWNTs towards the detection probe.     

An Integrated Intrusion Detection Model of Cluster-Based Wireless Sensor Network

Considering wireless sensor network characteristics, this paper combines anomaly and mis-use detection and proposes an integrated detection model of cluster-based wireless sensor network, aiming at enhancing detection rate and reducing false rate. Adaboost algorithm with hierarchical structures is used for anomaly detection of sensor nodes, cluster-head nodes and Sink nodes. Cultural-Algorithm and Artificial-Fish–Swarm-Algorithm optimized Back Propagation is applied to mis-use detection of Sink node. Plenty of simulation demonstrates that this integrated model has a strong performance of intrusion detection.     

食品中单核增生李斯特氏菌检测研究进展

单核增生李斯特氏菌和李斯特菌病的危害近年来引起世界各国食品和卫生部门的广泛关注.关于如何找到一种快速、敏感、准确、合理的检验方法,是当今各国食品卫生部门亟待解决的重要研究课题.对该菌的传统分离方法、免疫学检测方法、核酸检测等方法的最新进展进行了综述,为进行该菌的准确、快速检测奠定了基础.     

Accurate detection of dairy cow mastitis with deep learning technology: a new and comprehensive detection method based on infrared thermal images

Mastitis is one of the most common diseases in dairy cows and has a negative impact on their welfare and life, causing significant economic losses to the dairy industry. Many attempts have been made to develop a detection method for mastitis using thermal infrared thermography. However, the use of this detection technique to determine the health of the cow's udder is susceptible to external factors, resulting in inaccurate detection of dairy cow mastitis. Therefore, this study explored a new and comprehensive detection method of dairy cow mastitis based on infrared thermal images. This method combined the left and right udder skin surface temperature (USST) difference detection method with the ocular surface temperature and USST difference detection method with improvements. The effect of external factors on dairy cow USST was effectively reduced. In addition, after comparing different target localisation algorithms, this paper used the You Only Look Once v5 (YOLOv5) deep learning network model to obtain the temperature information of eyes and udders, and mastitis detection of dairy cows was performed. A total of 105 dairy cows passing through a passage were randomly selected from the thermal infrared video and detected by the new and comprehensive detection method, and the results of cow mastitis detection were compared with somatic cell count. The results showed that the accuracy, specificity, and sensitivity of mastitis detection were 87.62, 84.62, and 96.30%, respectively. Using the YOLOv5 deep learning network model to locate the key parts of the cow had a good effect, with an average accuracy of 96.1%, and an average frame rate of 116.3f/s. The detection accuracy of dairy cow mastitis by deep learning technology combined with the detection method in this paper reached 85.71%. The results showed that the new and comprehensive detection method based on infrared thermal images can be used for the detection of dairy cow mastitis with high detection accuracy. This method can reduce the influence of external factors and can be integrated into the automatic identification system of dairy mastitis based on YOLOv5 to realise on-site monitoring of dairy mastitis.     

High-performance liquid chromatographic separation and detection methods for anabolic compounds

The role of high-performance liquid chromatography (HPLC) in methods of analysis for anabolic compounds in biological samples is reviewed. Special attention is given to both the separation and detection of anabolic compounds. A distinction is made between on-line detection systems, such as ultraviolet detection and diode-array detection, and off-line detection methods with special emphasis on immunochemical detection methods using non-isotopic labels. A number of applications are given to elucidate the possibilities of HPLC in the analysis of anabolic compounds.     

Accounting for Imperfect Detection in Ecology: A Quantitative Review

Detection in studies of species abundance and distribution is often imperfect. Assuming perfect detection introduces bias into estimation that can weaken inference upon which understanding and policy are based. Despite availability of numerous methods designed to address this assumption, many refereed papers in ecology fail to account for non-detection error. We conducted a quantitative literature review of 537 ecological articles to measure the degree to which studies of different taxa, at various scales, and over time have accounted for imperfect detection. Overall, just 23% of articles accounted for imperfect detection. The probability that an article incorporated imperfect detection increased with time and varied among taxa studied; studies of vertebrates were more likely to incorporate imperfect detection. Among articles that reported detection probability, 70% contained per-survey estimates of detection that were less than 0.5. For articles in which constancy of detection was tested, 86% reported significant variation. We hope that our findings prompt more ecologists to consider carefully the detection process when designing studies and analyzing results, especially for sub-disciplines where incorporation of imperfect detection in study design and analysis so far has been lacking.