排序方式： 共有34条查询结果，搜索用时 243 毫秒
1.
Bin Huang Yun Yin Lei Lu Hai Ding Lin Wang Ting Yu Jia-jin Zhu Xiao-dong Zheng Yan-zhen Zhang 《Journal of Zhejiang University. Science. B》2010,11(10):812-818
A convenient competitive enzyme-linked immunosorbent assay (ELISA) for ciprofloxacin (CPFX) was developed by using rabbit
monoclonal antibodies (RabMAbs) against a hapten-protein conjugate of CPFX-bovine serum albumin (BSA). The indirect competitive
ELISA of CPFX had a concentration at 50% inhibition (IC50) of 1.47 ng/ml and a limit of detection (LOD) of 0.095 ng/ml. The mAb exhibited some cross-reactivity, however, not so high
with enrofloxacin (28.8%), ofloxacin (13.1%), norfloxacin (11.0%), fleroxacin (22.6%), and pefloxacin (20.4%). And it showed
almost no cross-reactivity with other antibiotics or sulfonamides evaluated in this study. The competitive ELISA kit developed
here could be used as a screening tool to detect and control illegal addition of CPFX in food products. This kit had been
applied to milk detection and the recovery rates from samples spiked by CPFX were in a range of 63.02%–84.60%, with coefficients
of variation of less than 12.2%. 相似文献
2.
A highly reliable, quantitative and sensitive analytical method for determining the residues of the fungicide, hexaconazole in black tea is described. The proposed method is based on liquid-liquid extraction followed by gas chromatographic determination, using nitrogen phosphorus detector (GC-NPD) for the identification and quantitation of hexaconazole. The most was cleaned up by adsorption column chromatography using activated florisil. Performance of the method was assessed by evaluating quality parameters such as recovery value, repeatability, reproducibility, linearity and limits of detection and quantitation. When the method was assessed for repeatability, the percentage of recovery ranged between 86% and 96% while the relative standard deviation was between 0.30% and 2.35%. In studies on reproducibility the recovery ranged from 81% to 85% and relative standard deviation from 1.68% to 5.13%, implying that the method was reliable. A field trial was conducted to verify the application of this method with real samples. Results prove that the validated method was suitable for extracting hexaconazole residues. 相似文献
3.
蔬菜中农残去除方法研究 总被引：3，自引：0，他引：3
以萝卜和菠菜为样品,采用正交试验,研究了不同方法组合对蔬菜中农残的去除效果.结果表明,去除根茎类蔬菜农残的方法组合为2%洗涤剂浸泡10min后,用自来水漂洗3次,每次1min后,再用沸水烫漂1min;去除叶菜类蔬菜农残的方法优化组合为2%洗涤剂浸泡15min后,用自来水漂洗2次,每次1min后,再用沸水烫漂1min. 相似文献
4.
An integrated and reliable phase unwrapping algorithm is proposed based on residues and blocking-lines detection, closed contour extraction and quality map ordering for the measurement of 3D shapes by Fourier-transform profilometry （FTP）. The proposed algorithm first detects the residues on the wrapped phase image, applies wavelet analysis to generate the blocking- lines that can just connect the residues of opposite polarity, then carries out the morphology operation to extract the closed contour of the shape, and finally uses the modulation intensity information and the Laplacian of Gaussian operation of the wrapped phase image as the quality map. The unwrapping process is completed from a region of high reliability to that of low reliability and the blocking-lines can prevent the phase error propagation effectively. Furthermore, by using the extracted closed contour to exclude the invalid areas from the phase unwrapping process, the algorithm becomes more efficient. The experiment shows the effectiveness of the new algorithm. 相似文献
5.
微生物降解有机磷农药的研究进展 总被引：1，自引：0，他引：1
果蔬菜等农产品有机磷农药残留越来越严重,利用微生物降解有机磷农药,在改善环境和人们生活质量方面已显得经济而有效。本文就降解有机磷农药的微生物种类,降解机制及编码降解酶的相应基因,以及工程菌的构建作了综述。 相似文献
6.
Mary L. Halbleib Paul C. Jepson 《The Journal of Agricultural Education and Extension》2015,21(2):109-126
Purpose: This paper examines the benefits of using an outcome-based education (OBE) method within agricultural extension outreach programmes for professional and farmer audiences. Design/Methodology/Approach: The method is elaborated through two practical examples, which show that focused, short-duration programmes can produce meaningful skill development and impacts at the farm level. Both examples addressed pressing problems that were evolving during the education programme, and we sought a method that would respond adaptively to local circumstances and unanticipated changes. Key aspects of the method include strategic planning to properly focus education programmes, and the integration of data-driven decision support tool development to reduce uncertainty associated with the use of high-risk pest management inputs. Findings: Professionals and farmers increased their knowledge and skills related to pesticide management, and follow-up evaluation documented high levels of adoption of risk reduction and mitigation practices by farmers. Practical Implications: We recommend OBE for several reasons: (1) it uses a group process to elicit an accurate view of the system that learners operate within, (2) it provides cohesive and active learning with the potential for continuation, and (3) it enables feedback between all stages of programme development and implementation. Originality/Value: The most novel aspect of our adaptation of the OBE approach is the integration of, and feedback between, participatory programme design and tool development throughout the process, which maximises the value of each, and their ability to deliver outcomes. The OBE method integrates science, technology and social learning, and connects these with authentic problem-solving tasks to perpetuate learning beyond the classroom to where outcomes are attained. 相似文献
7.
Terry Mark Stewart 《The Journal of Agricultural Education and Extension》2015,21(5):405-419
Purpose: There are many complexities to be considered when selecting tactical control options in crops grown under an Integrated Pest Management (IPM) regime. Students being trained in IPM are made aware of this complexity but do not always get the chance to experience IPM decision-making first-hand. This case study describes a web-based assessment and presents student feedback as to its value.
Design/Methodology/Approach: Students are required to analyse the pest and disease status of and provide pesticide recommendations for an export apple orchard at four different times of the season. At each ‘virtual visit’ they are required to interpret monitoring data and make spray decisions. The students are provided with the same IPM information and guidelines commercial growers receive. Amongst other things, management history, non-target organisms, pesticide resistance risk, allowable residues, pesticide restrictions and pesticide compatibility must be considered. Student reflections (n = 57) from three years of use were assessed using grounded theory analysis and reported.
Findings: Students found they gained an appreciation of the various factors that need to be considered for tactical IPM and that the exercise helped prepare them for this task ‘in real life’.
Practical Implications: The assessment described can be used as a template for an online integrated case-based training strategy which provides the opportunity for real-life decision making in a safe environment.
Originality/Value: The paper is original. It is hoped this case study will serve as a source of ideas and/or inspiration from those wishing to employ similar ‘active learning’ web-based exercises for agricultural education or extension training. 相似文献
8.
应用分子电性距离矢量(MEDV)对氨基甲酸酯类农药进行结构表征和急性毒性的定量预测,籍以多元线形性回归(MLR)建立了MEDV与生物毒性之间的相关模型,相关系数R=0.984,并通过逐步回归(SMR)方法建立了另一更具预测性的定量模型,取得了良好的结果,其模型相关系数为R=0.983;继以留一法(Leave-one-out,LOO)进行交互检验,相关系数为R2=0.922,说明定量相关模型具有良好的稳定性和预测能力. 相似文献
9.
Kallidass Subramaniam Jebakumar Solomon 《Indian journal of clinical biochemistry : IJCB》2006,21(2):169-172
In this study blood samples are taken from two groups of people, one that has direct exposure to pesticides (agriculturists
& public health workers) the second group, which has indirect exposure to pesticides through food chain. The objective of
our investigation is to analyze the blood of the patients with minimum health complaints and skin diseases for the residue
of the banned organochlorine pesticides DDE and BHC using Gas Chromatography. High concentrations of both BHC&DDE were observed
in the serum samples of the people who had direct exposure to the pesticides, namely agriculturalists and public health workers
with few exceptions. The pesticide residue concentration in serum ranges from 0.006 to 0.130 ppm for BHC and 0.002 to 0.033
ppm for DDE. Significance of this study reveals that the presence of these banned pesticides in human serum. 相似文献
10.
A total of 41 healthy male pesticide sprayers exposed to different clases of pesticides for 3-5 years were compared with 21
controls matched for age and economic status with respect to free radical generation, lipid peroxidation, antioxidant status,
cholesterol, lipoprotein status and haematological profile. Plasma lipid peroxidation was estimated in the form of thiobarbituric
acid reactive substances (TBARS) produced. Significant increase in TBARS was observed in sprayers population when compared
with control subjects and the level of TBARS increased with increase in the duration of exposure. The levels of antioxidants
such as glutathione (GSH) were significantly depleted, whereas those of superoxide dismutase (SOD) were remarkably increased
than control population. Significant reduction in total cholesetrol, alteration in lipoprotein fractions and nonsignificant
changes in hematological parameters were observed. These results suggested that exposure to pesticidal residual drift augments
the free radical generation, and lipid peroxidation. Decline in non-enzymatic antioxidant and elevation of enzymatic antioxidant
were observed. Supplementation of α-tocopherol for 45 days resulted in the partial restoration of these biochemical changes
produced by pesticides. 相似文献