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Elina Leonova Karlis Shvirksts Mara Grube Lubov Ignatovich Calvin Yu-Chian Chen Tatjana Sjakste 《毒物与环境化学》2017,99(4):601-612
Ftorafur is an antimetabolite antitumour drug successfully used for treatment of various tumours. It is generally accepted that ftorafur is converted to 5-fluoruracil. However, some data indicate direct interactions of the compound with DNA. To test this hypothesis we have performed spectrophotometric study of DNA interactions of ftorafur and some of its elementoorganic derivatives with DNA. UV-VIS spectra of the tested compounds were recorded in absence and presence of increasing amounts of DNA. DNA caused a hypochromic effect in spectra of ftorafur, similar, but weaker effect was observed in 5-fluoruracil spectra. Trimethylgermyl derivative of ftorafur manifested a higher DNA-binding capacity compared to ftorafur. To reveal possible mechanism of interaction between the tested nucleosides and DNA ethidium bromide extrusion experiments were performed. It was shown that the compounds did not compete with EBr for intercalation. Fourier transformation infrared spectroscopy analyses revealed decrease in intensity of several bands in spectra of ftorafur, its trimethylgermyl derivative and fluorouracil in presence of DNA indicating again interactions between the compounds and DNA. Docking experiments reveal interactions of the tested nucleosides with the DNA minor groove. Thus ftorafur is capable to interact directly with DNA; further modifications of the molecule enhance this capacity. 相似文献
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Gerhard Lammel V. S. Semeena Francesca Guglielmo Tatjana Ilyina Adrian Leip 《Environmental Sciences Europe》2006,18(4):254-261
Background, Aim and Scope
Many environmental pollutants are slowly degrading (persistent) and very mobile. They are semivolatile, i.e. they are partitioned between the environmental media of soil, water and air, and undergo long-range transport. The combined action of climate and substance properties determines the distributions and fate of these substances, among them as the persistent organic pollutants (POPs), other pesticides and industrial chemicals.Main Features
Multicompartment chemistry-transport models are under development in order to study environmental exposure models.Results
The investigation of transport and fate of some POPs on the global scale has emphasized the significance of historically explicit and geo-referenced simulations for substance distributions, persistence and long-range transport potential. Apart from the substance properties, it is the regional climate which is most important. This was illustrated by studies into the regional cycling of DDT and γ-HCH in selected tropical and extra-tropical regions.Discussion
The isolation of individual steps of subsequent cycles of emission, transport and deposition (a so-called grasshopper effect) in model experiments shows the potential to elucidate the complex superposition of substance properties and environmental conditions, variable in time and space.Conclusions
The results suggest that the grasshopper effect enhances the long-range transport potential, but is not required to explain an accumulation in polar regions (at least for γ-HCH).Perspectives
A number of relevant scientific questions should be addressed by exposure modelling. 相似文献14.
Estimating the Carbon Content of Russian Forests; A Comparison of Phytomass/Volume and Allometric Projections 总被引:1,自引:0,他引:1
Hamburg Steven P. Zamolodchikov Dmitri G. Korovin George N. Nefedjev Viktor V. Utkin Anatoly I. Gulbe Jakov I. Gulbe Tatjana A. 《Mitigation and Adaptation Strategies for Global Change》1997,2(2-3):247-265
Mitigation and Adaptation Strategies for Global Change - As increased attention is being paid to the role Russian forests play in the global carbon budget, the desirability of being able to... 相似文献
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Sikoparija B Pejak-Šikoparija T Radišić P Smith M Soldevilla CG 《Journal of environmental monitoring : JEM》2011,13(2):384-390
Pollen data have been recorded at Novi Sad in Serbia since 2000. The adopted method of producing pollen counts has been the use of five longitudinal transects that examine 19.64% of total sample surface. However, counting five transects is time consuming and so the main objective of this study is to investigate whether reducing the number to three or even two transects would have a significant effect on daily average and bi-hourly pollen concentrations, as well as the main characteristics of the pollen season and long-term trends. This study has shown that there is a loss of accuracy in daily average and bi-hourly pollen concentrations (an increase in % ERROR) as the sub-sampling area is reduced from five to three or two longitudinal transects. However, this loss of accuracy does not impact on the main characteristics of the season or long-term trends. As a result, this study can be used to justify changing the sub-sampling method used at Novi Sad from five to three longitudinal transects. The use of two longitudinal transects has been ruled out because, although quicker, the counts produced: (a) had the greatest amount of % ERROR, (b) altered the amount of influence of the independent variable on the dependent variable (the slope in regression analysis) and (c) the total sampled surface (7.86%) was less than the minimum requirement recommended by the European Aerobiology Society working group on Quality Control (at least 10% of total slide area). 相似文献
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Zorana Kljaković-Gašpić Snježana Herceg Romanić Tomislav Bituh Vilena Kašuba Irena Brčić Karačonji Nataša Brajenović Iva Franulović Jasna Jurasović Darija Klinčić Nevenka Kopjar Gordana Marović Mirta Milić Tatjana Orct Ankica Sekovanić Davor Želježić 《Environmental monitoring and assessment》2018,190(11):694
In this study, the influence of anthropogenic pollution on the aquatic environment of Plitvice Lakes National Park (PLNP) was investigated during 2011–2012 using a combination of chemical and cytogenetic analyses. Four groups of major contaminants [(volatile organic compounds: benzene, toluene, ethylbenzene, and xylenes (BTEX); persistent organochlorine pollutants: organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs); major and trace elements; anthropogenic radionuclides (90Sr, 134Cs, and 137Cs)] were determined in three aquatic compartments (water, sediment, fish). Mass fractions of inorganic constituents in different compartments reflected the geological background of the area, indicating their origin from predominantly natural sources. Levels of volatile and persistent organic compounds in water and fish, respectively, were very low, at levels typical for remote pristine areas. Analysis of anthropogenic radionuclides in water and sediment revealed elevated activity concentrations of 137Cs in water, and measurable 134Cs in the upper sediment layers from April 2011, possibly as a consequence of the Fukushima nuclear accident in March 2011. The potential genotoxicity of river and lake water and lake sediment was assessed under laboratory conditions using the alkaline comet assay on human peripheral blood lymphocytes, and measured levels of primary DNA damage were within acceptable boundaries. The results showed that despite the protected status of the park, anthropogenic impact exists in both its terrestrial and aquatic components. Although contaminant levels were low, further monitoring is recommended to make sure that they will not rise and cause potentially hazardous anthropogenic impacts. 相似文献
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Water supply is a major problem in the Adriatic islands, especially during the summer tourism season, and represents a limiting factor to the islands' further economic development. Much attention has been given to water supply solutions, primarily in terms of attempting to use the existing island water. Unfortunately, few islands have favourable hydrological conditions to accumulate significant quantities of surface water or groundwater. In the period from 2001 to 2004, investigations were conducted on many islands to define their own freshwater or partially brackish water resources since desalinisation technology could resolve a significant part of the water supply demand on small and distant islands. Due to the specificity and complexity of research in karst areas, the study was conducted in phases and included the geological and hydrogeological reconnaissance of the island, aimed at locating possible areas on the island where the necessary quantities of groundwater of adequate quality could be captured; a detailed hydrogeological mapping of the specified areas, geophysical investigation and test drilling; and, over several days, test pumping of the most promising borehole. One of the islands investigated was the island of Olib. The conducted surveys indicated that it is possible to pump about 3.5 L/s of groundwater from the karst aquifer of the island of Olib, which fully complies with the sanitary quality of drinking water. 相似文献
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Darinka Gjorgieva Ackova Tatjana Kadifkova-Panovska Katerina Bačeva Andonovska Trajče Stafilov 《Journal of environmental science and health. Part. B》2016,51(5):340-349
This study was designed to assess the effects of long term, high metal exposition (cadmium, lead, copper, nickel and zinc) on DNA damage in four plant model systems [Taraxacum officinale (Asteraceae), Matricaria recutita L. (Asteraceae), Robinia pseudoacacia L. (Fabaceae), and Urtica dioica (Urticaceae)]. DNA stability was investigated by a Random Amplified Polymorphic DNA (RAPD) technique. Agarose-gel electrophoresis revealed total of 37 bands with different molecular weights ranging from 1250 to 5000 bp. It generated distinctive polymorphism value of 72.97% (27 bands) total in four plant species investigated. The dendrogram constructed using NTSYSpc programme showed that there is grouping in separate clusters of the same plant model collected from two different areas (metal-exposed and control samples). The study concluded that the long term metal-exposing periods had genotoxic stress on macromolecules of plant model systems investigated and biomarkers used should be augmented for reliable estimates of genotoxicity after exposure of plants to metal stressors. 相似文献
19.
Concentration of trace elements in blood and feed of homebred animals in Southern Serbia 总被引:1,自引:1,他引:0
Dragana Popovic Tatjana Bozic Jelka Stevanovic Marina Frontasyeva Dragana Todorovic Jelena Ajtic Vesna Spasic Jokic 《Environmental science and pollution research international》2010,17(5):1119-1128
Background, aim and scope
The paper presents concentrations of trace elements in blood of homebred animals (cows and sheep) from Southern Serbia (Bujanovac) and the contents of natural and anthropogenic radionuclides and some heavy metals in feed. The region of Southern Serbia was exposed to contamination by depleted uranium ammunition during NATO attacks in 1999 and therefore, is of great concern to environmental pollution and human and animal health. 相似文献20.
As a member of the British Oxford Group, psychologist Richard Ryder marked the beginning of the modern animal rights and animal welfare movement in the seventies. By introducing the concept “speciesism.” Ryder contributed importantly to the expansion of this movement. Surprisingly little attention has been paid to Ryder’s moral theory, “painism”, that aims to resolve the conflict between the two predominant rival theories in animal ethics, the deontological of Tom Regan and the utilitarian of Peter Singer. First, this paper examines the kernel and historical sources of Ryder’s painist theory, linking it to the work of John Rawls and Jean-Jacques Rousseau. Second, it examines Ryder’s critique of utilitarianism. It is argued that his critique of Singer’s use of the word “sentience” is unconvincing and that his critique of utilitarian aggregation as not taking a full account of the metaphysical separateness of persons, has already been countered and dealt with. Finally this paper looks at some of the counterintuitive implications of Ryder’s theory and argues that utilitarianism might have more resources for dealing with its own alleged counterintuitive implications than Ryder acknowledges. 相似文献