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171.
Isolation and structure of a covalent cross-link adduct between mitomycin C and DNA 总被引:13,自引:0,他引:13
M Tomasz R Lipman D Chowdary J Pawlak G L Verdine K Nakanishi 《Science (New York, N.Y.)》1987,235(4793):1204-1208
A DNA cross-link adduct of the antitumor agent mitomycin C (MC) to DNA has been isolated and characterized; the results provide direct proof for bifunctional alkylation of DNA by MC. Exposure of MC to Micrococcus luteus DNA under reductive conditions and subsequent nuclease digestion yielded adducts formed between MC and deoxyguanosine residues. In addition to the two known monoadducts, a bisadduct was obtained. Reductive MC activation with Na2S2O4 (sodium dithionite) leads to exclusive bifunctional alkylation. The structure of the bisadduct was determined by spectroscopic methods that included proton magnetic resonance, differential Fourier transform infrared spectroscopy, and circular dichroism. Formation of the same bisadduct in vivo was demonstrated upon injection of rats with MC. Computer-generated models of the bisadduct that was incorporated into the center of the duplex B-DNA decamer d(CGTACGTACG)2 indicated that the bisadduct fit snugly into the minor groove with minimal distortion of DNA structure. A mechanistic analysis of the factors that govern monofunctional and bifunctional adduct formation is presented. 相似文献
172.
Skrzecz Iwona Sukovata Lidia Jabłoński Tomasz Sowińska Alicja Szmidla Hanna 《Journal of pest science》2021,94(4):1393-1404
Journal of Pest Science - The protection of reforested areas against the large pine weevil Hylobius abietis is one of the greatest forest management challenges in many European countries. No... 相似文献
173.
Niemczyk Marzena Chmura Daniel J. Socha Jarosław Wojda Tomasz Mroczek Piotr Gil Wojciech Thomas Barb R. 《European Journal of Forest Research》2021,140(6):1341-1361
European Journal of Forest Research - The contribution of Douglas-fir (Df) to European forests is likely to increase as the species is a potential adaptation option to climate change. In this... 相似文献
174.
Regenerating arms of crinoids represent direct evidence of nonlethal attacks by predators and provide an opportunity for exploring the importance of predation through geologic time. Analysis of 11 Paleozoic crinoid Lagerst?tten revealed a significant increase in arm regeneration during the Siluro-Devonian. During this interval, referred to as the Middle Paleozoic Marine Revolution, the diversity of shell-crushing predators increased, and antipredatory morphologies among invertebrate prey, such as crinoids, became more common. Crinoid arm regeneration data suggest an increase in nonlethal attacks at this time and represent a causal link between those patterns, which implies an important role for predator-driven evolution. 相似文献
175.
Kowalewski M Hoffmeister AP Baumiller TK Bambach RK 《Science (New York, N.Y.)》2005,308(5729):1774-1777
The fossil record of predation indicates that attacks on Paleozoic brachiopods were very rare, especially compared to those on post-Paleozoic mollusks, yet stratigraphically and geographically widespread. Drilling frequencies were very low in the early Paleozoic (<1%) and went up slightly in the mid-to-late Paleozoic. Present-day brachiopods revealed frequencies only slightly higher. The persistent rarity of drilling suggests that brachiopods were the secondary casualties of mistaken or opportunistic attacks by the enemies of other taxa. Such sporadic attacks became slightly more frequent as trophic systems escalated and predators diversified. Some evolutionarily persistent biotic interactions may be incidental rather than coevolutionary or escalatory in nature. 相似文献
176.
Joanna O'Keeffe Mikoaj Piniewski Mateusz Szczeniak Pawe Oglcki Piotr Parasiewicz Tomasz Okruszko 《Fisheries Management and Ecology》2019,26(6):474-485
Climate change is expected to affect the flow regime, cause loss of habitat, change community composition and behavioural habits of fish. This study assessed the impact of climate change on ecologically relevant streamflow conditions for fish migration and spawning in the Vistula and the Odra river basins. Streamflow simulations obtained with the Soil and Water Assessment Tool (SWAT) for the historical period and two future horizons were driven by nine bias‐corrected EURO‐CORDEX Regional Climate Models under two greenhouse gas concentration trajectories. This study identified a subset of Indicators of Hydrological Alteration (IHA) that are relevant for pike, Esox lucius L., chub, Squalius cephalus (L.), and Atlantic salmon, Salmo salar L. IHA indicators were calculated and compared for different scenarios. An index‐based framework identified that all considered species will be impacted by climate change, with Atlantic salmon facing the largest impact. The model's uncertainty was addressed through an aggregation method that assessed inconsistencies in the model's response. 相似文献
177.
Tomasz Lesiow Herbert W. Ockerman Konrad Dabrowski 《Journal of the World Aquaculture Society》2009,40(5):678-686
Rainbow trout were fed a fish meal‐based diet or diets where 25, 50, 75, or 100% of the fish meal protein was replaced with a mixture of rendered animal protein ingredients. Diets were formulated to be iso‐nitrogenous (36% crude protein) and meet all known nutrient requirements of rainbow trout. The effect of five diets on dressing percentage, chemical composition, functional properties, and sensory characteristics of rainbow trout fillets stored up to 1 wk on ice in a refrigerated room (4 C) was determined. Dressing percentage based on body weight (from 724 to 811 g) did not show a significant difference due to the diet. Raw tissue pH, 24 and 144 h post mortem, were significantly lower than the control when 75 and 100% fish meal replacement were utilized. Assessment of color, texture, flavor, and tenderness indicated that fillet were lighter, less firm, more bland, and more tender after 144 h compared to 24‐h storage time. Fillets from fish fed all diets were considered as acceptable by the panel. 相似文献
178.
Migena Gjoni Gündemir Tomasz Szara Constantin Spataru Ismail Demircioglu Bernard Turek Georgios Petrovas Mihaela Claudia Spataru 《Anatomia, histologia, embryologia》2023,52(2):190-196
The anatomy of the sternum in birds varies according to their habitats and type of locomotion. In particular, the carina sterni manifest different shape variations. In this study, the shape of the carina sterni was investigated by means of geometric morphometrics. Birds of different types of locomotion were used in the study: flying, swimming, and terrestrial. Ducks and chickens show a wider variety of shapes. Pigeons are the species with the least differences. The margo cranialis carinae in a turkey is the flattest compared to other species. In chickens, the apex carinae is more caudally than the base of the carina sterni. The margo cranialis of the carina sterni in ducks is concave. The differences in centroid size and shape differences between species collectively are statistically significant (p < 0.0001). The most distinct shape contrast is between the duck and turkey (p: 0.0003). Form differences between the ducks and geese as well as between the chicken and turkey are statistically insignificant. There is less variation in the shape of the carina sterni among avian species representing the same type of locomotion. Although there are many comparative morphological and morphometric studies of birds, shape analysis studies revealing the interspecific differences and similarities of the sternum are very limited. Morphology of the carina sterni can be useful in taxonomic investigations. 相似文献
179.
Effect of soil drought on growth and yield of maize (Zea mays L.) hybrids grown under compacted soil
Maciej T. Grzesiak Tomasz Hura Anna Maksymowicz Kinga Dziurka Grzegorz Rut Andrzej Rzepka Stanisław Grzesiak 《Journal of Agronomy and Crop Science》2023,209(2):300-315
In this study, we examined responses of maize hybrids differing in susceptibility to soil compaction and drought in the case of their separate or combined action. We ran field and greenhouse experiments and determined effects on grain yield, biomass, weight of 1000 grains, shoot and roots dry matter (DM), shoot-to-roots ratio, harvest index, plant height, emergence index, leaf area and greening and root number and length. Individual and combined effects of both stresses were observed in the field and greenhouse. Compared with plants growing in loose soil and optimal irrigation (LI), the resistant hybrids in treatments HI, LD and HD showed a smaller reduction in GY, BY, S, R, RN and RL than the sensitive. In both groups, stress influence on HA, W-1000, LA and SPAD was smaller and the differences were insignificant. Compared with LI treatment, the roots of LD, HI and HD increased their DM, number and length in the upper level of the soil profile and the number of roots developed at 0–30° and 30–60° in relation to the root main axis. Analysis of those traits in the hybrids resistant and sensitive to both stress factors enabled to explain a defence response. Our study demonstrated that soil compaction and soil drought, which usually occurs simultaneously, caused significant changes in components of plant yield and showed plant plasticity in response to environmental factors under natural conditions. 相似文献