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792 Babai, L., Szigeti, Zs., Parratt, J. R., Végh, Á. (2002) Delayed cardioprotective effects of exercise in dogs are aminoguanidine sensitive: possible involvement of nitric oxide. Clin

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Serotonin (5-HT) is known to induce a wide range of short-term and long-term (or delayed) effects. In the present paper we demonstrated that short time-window application of the 5-HT precursor 5-hydroxytryptophan during early cleavage stages results in both irreversible morphological malformation (exogastrulation) and distinct changes in behavior of young animals of the freshwater snail, Lymnaea stagnalis (Mollusca: Gastropoda). Pharmacological and immunocytochemical analysis confirmed that both the increase of intracellular 5-HT level within the cleaved blastomers and activation of membrane 5-HT2-like type receptors are required for the appearence of these phenomena.

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., Singh, U. P. (1992) Morphometric changes in the ovaries of Indian vespertilionid bat, Scotophilus heathi with reference to delayed ovulation. Eur. Arch. Biol. 103 , 257-264. Morphometric changes in the ovaries of Indian

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The development of local early basal resistance (EBR), is a form of non-specific general defence response of plants to bacteria, greatly depending on temperature. This symptomless defence mechanism is easily detected by its inhibitory action on the hypersensitive response (HR) caused by a subsequent incompatible pathogenic bacterium. Both EBR and HR were investigated at different temperatures ranging from 30 °C to 5 °C. At normal temperatures (30-20 °C) both heat-killed Pseudomonas syringae pv. syringae 61 (polyvirulent to many plants) and Pseudomonas savastanoi pv. phaseolicola S21 (pathogenic to bean) induced EBR in tobacco leaves within a few hours, but below 10 °C it was greatly delayed and at 5 °C usually no EBR response could be detected within 2-3 days. The time required for development of EBR did not depend on the bacterial pathovars or strains. However, the induction time of HR was not as sensitive to low temperatures as that of EBR, instead, it depended on the bacterial pathovars used.

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Connor, J. A., Stevens, C. F. (1971) Inward and delayed outward membrane currents in isolated neuronal somata under voltage clamp. J. Physiol. 213 , 1-19. Inward and delayed outward membrane currents in isolated neuronal somata

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Parisi, V., Scarale, M. E., Balducci, N., Fresina, M., Campos, E. C. (2010) Electrophysiological detection of delayed postretinal neural conduction in human amblyopia. Invest. Ophthalmol. Vis. Sci. 51 , 5041

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The effects of ethyl alcohol and synthetic β-carotene have been studied on two models of carcinogenesis in mice BALB/c. Lung tumours were induced with organotropically acting urethane (given by i.p. injections, total dose -100 mg/mouse), subcutaneous tumours were induced with locally acting benzo(a)pyrene (single injection, 2 mg/mouse). β-Carotene was given 3 times per week 0.4 mg/mouse by gastric intubations and 10% ethanol was given instead of drinking water until the end of experiments (4-6 months). Results showed that β-carotene did not significantly inhibit lung adenomogenesis and may moderately delay subcutaneous tumours occurrence. In our studies chronic ethanol intake did not show significant influence on this delay.

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Acta Biologica Hungarica
Authors: Ildikó Karsai, B. Kőszegi, G. Kovács, P. Szűcs, Klára Mészáros, Z. Bedő, and O. Veisz

In order to analyse the effects of temperature (9–22 °C) and light intensity (170–576 μmol m −2 s −1 ) on plant development two barley varieties with contrasting seasonal growth habits were included in a series of experiments consisting of controlled environment tests. The effect of constant (18 °C) and daily fluctuating (18/16 °C) temperature with a long photoperiod was also examined in a set of barley varieties including winter, facultative and spring barleys. Dicktoo with facultative growth habit was more sensitive to unfavourable conditions than Kompolti korai with winter growth habit; the flowering of Dicktoo was significantly delayed by sub-and supra-optimal temperatures and low light intensity accompanied by higher or fluctuating temperatures. The optimal temperature at flowering was also significantly lower for Dicktoo than for Kompolti korai (16.0 °C vs. 21.0 °C, respectively). Plant development was the fastest when there was no fluctuating environmental factor in the growing conditions and was significantly delayed with application of photo cycle. The addition of thermo cycle to photo cycle had an even stronger delaying effect. Facultative barleys were the most sensitive, followed by winter barleys, while spring barleys the least sensitive to the introduction of thermo cycle.

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We imposed two different global changes, climate warming and declining species richness, to synthesized grassland ecosystems, in order to determine both their single-factor effect as well as their possible interactions on plant phenology. Twelve climate-controlled chambers were therefore exposed to two temperature treatments (0 °C and 3 °C above ambient air temperature) and three species richness treatments (1,3 and 9 species). Measurements consisted of visual phenological observations of the appearance of flower buds until flowering and of autumn senescence stages, as well as of readings of the leaf chlorophyll content. In spring, chlorophyll concentrations increased under warming (9.7%) and decreasing species richness (39.4%). Warming also induced an earlier spring start (4 days) and enhanced flower production, whereas decreasing species richness likewise enhanced flower production but delayed the start of spring (16 days). In autumn, leaf senescence started simultaneously at the two temperature treatments and three species richness levels, but the end of the senescence was delayed in the heated chambers, as well as in the monocultures. Although warming and species richness interacted with species identity, no warming×species richness interactions were found. In conclusion, although warming and species richness influenced the duration of the growing season, none of these effects were reflected in the above-ground biomass of the individual plants. Under the projected climatic changes, warming will therefore not necessarily enhance the productivity of the individual plants.

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Mendham, N. J., Shipway, P. A. 1981: The effects of delayed sowing and weather on growth, development and yield of winter oilseed rape. J. Agric. Sci. Camb. , 96 , 389-416. The effects

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