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61.
Uptake of veterinary medicines from soils into plants 总被引:17,自引:0,他引:17
Boxall AB Johnson P Smith EJ Sinclair CJ Stutt E Levy LS 《Journal of agricultural and food chemistry》2006,54(6):2288-2297
Medicines play an important role in the treatment and prevention of disease. Whereas the side effects on human and animal health resulting directly from treatment have been widely documented, only recently have the occurrence and fate of medicines in the environment and the potential consequences for human health been recognized as an issue warranting consideration. Medicines have been shown to be released to soils and to persist in the environment. This study was performed to investigate the potential for a range of veterinary medicines to be taken up from soil by plants used for human consumption and to assess the potential significance of this exposure route in terms of human health. Soil analyses indicated that, for selected substances, measurable residues of these are likely to occur in soils for at least 5 months following application of manure containing these compounds. Experimental studies on the uptake of veterinary medicines into carrot roots (tubers) and lettuce leaves showed that only florfenicol, levamisole, and trimethoprim were taken up by lettuces, whereas diazinon, enrofloxacin, florfenicol, and trimethoprim were detected in carrot roots. Measured concentrations in plant material were used to model potential adult human exposure to these compounds. Although exposure concentrations were appreciable in a few instances, accounting for approximately 10% of the acceptable daily intake values (ADI), all were lower than the ADI values, indicating that, at least for compounds with properties similar to those considered here, there is little evidence of an appreciable risk. This exposure route may, however, be important when veterinary medicines have a very low ADI, at which they elicit subtle effects over prolonged periods, or when exposure is occurring via a number of routes at once. Although degradation products (produced in the soil or the plant) were not measured, it is possible for some substances that these could increase the risks to consumers. 相似文献
62.
以白三叶(Trifolium repens L.)的两个品种Irrigation和Huia的子叶为转化体,用根癌农杆菌(Agrobacterium tumefaciens)介导法将外源的苜蓿花叶病毒外壳蛋白基因转入白三叶,经过筛选、分化和再生,得到了具有卡拉霉素抗性的再生植株。对这些植株进行PCR、Southern和Northern分析,结果表明,外源目的基因已经整合到白三叶基因组中并且得到了表达。对Northern分析呈阳性的植株进行了抗病性检测,证明表达苜蓿花叶病毒外壳蛋白基因的植株病症减轻,发病率、病情指数及病毒积累量都明显低于对照,有的甚至不表现症状,达到了免疫的程度。 相似文献
63.
Handelman GJ Cao G Walter MF Nightingale ZD Paul GL Prior RL Blumberg JB 《Journal of agricultural and food chemistry》1999,47(12):4888-4893
Milled oat groat pearlings, trichomes, flour, and bran were extracted with methanol and the fractions tested in vitro for antioxidant capacity against low-density lipoprotein (LDL) oxidation and R-phycoerythrin protein oxidation in the oxygen radical absorbance capacity (ORAC) assay. The oxidative reactions were generated by 2,2'-azobis(2-amidinopropane) HCl (AAPH) or Cu(2+) in the LDL assay and by AAPH or Cu(2+) + H(2)O(2) in the ORAC assay and calibrated against a Trolox standard to calculate Trolox equivalents (1 Trolox equivalent = 1 TE = activity of 1 micromol of Trolox). The antioxidant capacity of the oat fractions was generally consistent with a potency rank of pearlings (2.89-8.58 TE/g) > flour (1.00-3.54 TE/g) > trichome (1.74 TE/g) = bran (1.02-1.62 TE/g) in both LDL and ORAC assays regardless of the free radical generator employed. A portion of the oat antioxidant constituents may be heat labile as the greatest activity was found among non-steam-treated pearlings. The contribution of oat tocols from the fractions accounted for <5% of the measured antioxidant capacity. AAPH-initiated oxidation of LDL was inhibited by the oat fractions in a dose-dependent manner, although complete suppression was not achieved with the highest doses tested. In contrast, Cu(2+)-initiated oxidation of LDL stimulated peroxide formation with low oat concentrations but completely inhibited oxidation with higher doses. Thus, oats possess antioxidant capacity most of which is likely derived from polar phenolic compounds in the aleurone. 相似文献
64.
Robert J. Diaz Lars Johan Hansson Rutger Rosenberg Paul C. Gapcynski Michael A. Unger 《Water, air, and soil pollution》1993,66(3-4):251-266
It is possible to rapidly detect the presence of high concentrations of sediment associated hydrocarbons using a sediment profile camera and simultaneously evaluate the general sedimentological and biological character of a contaminated area. In sediments that were heavily contaminated with hydrocarbons from spills and chronic long-term additions the presence of hydrocarbons was seen about 50% of the time in the sediment profile images as unique features, ‘H spots’. The presence of these features was related to the concentration of hydrocarbons in the sediment. In highly contaminated muddy sediments ‘H spots’ were found in images collected at stations that had from 270 to 610 ppt total hydrocarbons. Sedimentological and biological information obtained from the sediment profile images confirmed the impacted nature of Elizabeth River sediments. Sediment profile imaging provide a means of obtaining an overall evaluation of the quality of a habitat and impacts on that habitat from pollution related environmental disturbances. While qualitative, an advantage of sediment profile image data is that they can be evaluated in less than a day and used to quickly locate inclusions of hydrocarbons in the sediments for further quantitative chemical or biological sampling, or mapping of heavily contaminated areas. 相似文献
65.
Mathias?FosuEmail author Ronald?F.?Kühne Paul?L.?G.?Vlek 《Biology and Fertility of Soils》2003,39(2):117-122
In order to understand the efficiency of residue-N use and to estimate the minimum input required to obtain a reasonable level of crop response, it is important to quantify the fate of the applied organic-N. The recovery of N from 15N-labelled Crotalaria juncea was followed in the soil and the succeeding maize crop. Apparent N recovery (ANR) by maize from unlabelled Crotalaria juncea, Crotalaria retusa, Calopogonium mucunoides, Mucuna pruriens and mineral fertilizer at three locations were also evaluated. The maize crop recovered 4.7% and 7.3% of the 15N-labelled C. juncea-N at 42 days after sowing (DAS) and at final harvest, respectively. The corresponding 15N recovery from the soil was 92.4% and 58.5%. The highest mean ANR of 57.4% was with mineral fertilizer, whereas the mean ANR of 14.3% from C. retusa was the lowest. A large pool substitution and added-N interaction effect was observed when comparing N recovery from the labelled and unlabelled C. juncea. The amount of residue-N accounted for by the isotope dilution method at 42 DAS was 97.1% and at final harvest 65.8%. The large residue-N recovery in the soil organic-N pool explains the residual effect usually observed with organic residue application. 相似文献
66.
3个小麦重组自交系群体抗赤霉病QTLs的SSR分析 总被引:13,自引:1,他引:13
对3个重组自交系群体(RILs)苏麦3号/Alondra F_7、望水白/Alondra F_8、894037/Alondra F_8进行SSR分析,用单个标记方差及回归分析方法,结合接种鉴定资料,寻找与抗赤霉病性有关的的SSR分子标记。结果显示,在这3个抗病亲本的3B染色体上都存在一个主效抗赤霉病QTL,分别能解释2.6%~6.7%(苏麦3号)、47.4%(894037)、8.9%~27.0%(望水白)的抗性表型变异。在其它一些染色体上也发现一些微效QTLs,如2D、4B、4D、7A、6B染色体上,其中存在于4B染色体上的一个QTL来源于感病品种Alondra。在望水白/Alondra F_8群体中检测到了1个存在于2D染色体的抗赤霉病QTL,来源于抗病品种望水白,而在894037/Alondra F_8群体上检测到的1个存在于2D染色体的抗赤霉病QTL,则来源于感病品种Alondra,对其真实性将进一步研究。 相似文献
67.
Regional economic resilience can be defined as an economy’s ability to withstand and recover quickly from shocks. The ability to measure resilience is necessary to developing our understanding of what influences resilience. In this paper, we develop a new, two‐dimensional quantitative measure of resilience using observed differences between expected and actual employment in a region following a shock and distinguish the response to the shock from random variation. We demonstrate one application of this metric to US county‐level employment data to compare county responses to the 2007–2009 national recession and discuss how different regions of the United States responded to the shock of the Great Recession in terms of resilience. 相似文献
68.
Sameer Kumar Chanda Venkata Ganga Rao Nadigatla Veera Prabha Rama Rachit K. Saxena Kulbhushan Saxena Hari D. Upadhyaya Moses Siambi Said N. Silim Kothapally Narasimha Reddy Anupama J. Hingane Mamta Sharma Shivali Sharma Stephen Dominic Lyimo Rose Ubwe Meshack Makenge Kananji Gad Paul Kiprotich Kimurto Manuel Amane Kennedy Kanenga Yuventino Obong Emanuel Monyo Chris Ojiewo Nagesh Kumar Mallela Venkata Jaganmohan Polineni Rao Prashanthi Lakkireddy Sudhakar Chourat Indraprakash Singh Sobhan Sajja Shruthi Hirikara Beliappa Rajeev K. Varshney 《Plant Breeding》2019,138(4):445-454
In the past five decades, constant research has been directed towards yield improvement in pigeonpea resulting in the deployment of several commercially acceptable cultivars in India. Though, the genesis of hybrid technology, the biggest breakthrough, enigma of stagnant productivity still remains unsolved. To sort this productivity disparity, genomic research along with conventional breeding was successfully initiated at ICRISAT. It endowed ample genomic resource providing insight in the pigeonpea genome combating production constraints in a precise and speedy manner. The availability of the draft genome sequence with a large‐scale marker resource, oriented the research towards trait mapping for flowering time, determinacy, fertility restoration, yield attributing traits and photo‐insensitivity. Defined core and mini‐core collection, still eased the pigeonpea breeding being accessible for existing genetic diversity and developing stress resistance. Modern genomic tools like next‐generation sequencing, genome‐wide selection helping in the appraisal of selection efficiency is leading towards next‐generation breeding, an awaited milestone in pigeonpea genetic enhancement. This paper emphasizes the ongoing genetic improvement in pigeonpea with an amalgam of conventional breeding as well as genomic research. 相似文献
69.
Landscape Ecology - Habitat loss and fragmentation contribute significantly to pollinator decline and biodiversity loss globally. Conserving high quality habitats whilst restoring and connecting... 相似文献
70.