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We examined effects of UV and visible light irradiation on mycelial growth and sclerotium formation of Sclerotinia sclerotiorum. The irradi­ation with UV had no effect on the production of sclerotia. However it had strong inhibitory action on the growth of mycelia. In cultures of the fungus irradiated with yellow and green light more but small sclerotia developed mainly in the perimeter of culture at the time of irradiation and between this circle and the wall of Petri dishes. In cultures irradiated with red and blue light, a few, but large sclerotia developed.

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It is inferred from the thermoanalytical data obtained on 0.2–4.0M solutions of Fe(ClO4)2 which are frozen under non-equilibrium conditions that the phase containing the solute ions turns into a glassy state below −95°. On the warming of these solutions exothermic and endothermic processes are observed which can be related to the effects observed by the nuclear gamma resonance method.

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Absztrakt

Célkitűzés: A szerzők visszatekintő és összehasonlító tanulmányukban keresik a választ a fiatalkori aortabillentyű-hibák Ross-féle autograft-, illetve mechanikus műbillentyű beültetés javallataira a hosszú távú eredmények alapján. Beteganyag, módszerek: A szerzők 1992–2002 között 34 fiatal (18–35 éves) beteget operáltak súlyos aortavitium miatt. Egyaránt 17-17 betegnél Ross-műtét, illetve mechanikus aortaműbillentyű beültetés történt. Hét beteg anatómiai rendellenességek (méretaránytalanság 3, kóros falszerkezet 2, rendellenes koszorúér 2 eset), öt beteg pedig élettani okok (kezelhetetlen hypertonia 2, rossz bal kamra 2, aktív endocarditis 1 eset) miatt volt alkalmatlan a tervezett Ross-műtét elvégzésére. Három további betegnél saját kérésre, két esetben megfelelő méretű pulmonalis homograft hiánya következtében történt mechanikus műbillentyű beültetése. Eredmények: Korai halálozás egyik csoportban sem volt, és valamennyi beteget utánvizsgálták (utánkövetési idő 64,4 ± 26,8 hónap). Az aortaműbillentyű-beültetésen átesett betegek körében két késői haláleset volt (műbillentyű-endocarditis okozta sepsis, illetve végstádiumú szívelégtelenség). A műbillentyűs csoportban az utánkövetési idő alatt összesen két betegnél alakult ki műbillentyű-endocarditis, két másik betegnél pedig a véralvadásgátlással kapcsolatos szövődmény lépett fel. Ross-műtétet követően egy betegnél alakult ki korai endocarditis (fertőzött homograft következtében), egy másik kisebb tüdőemboliát szenvedett. Egy esetben észleltek enyhe aortaelégtelenséget a Ross-műtétet követően. A bal kamra végdiastolés átmérője és falvastagsága a Ross-műtétet követően jelentősen kisebbnek bizonyult, mint a műbillentyű-beültetést követően (p = 0,049 és p = 0,017). Következtetések: Ross-műtétet követően a bal kamrai izomtömeg gyorsabban és nagyobb mértékben csökken, mint műbillentyű-beültetést követően. A tökéletesebb bal kamrai helyreállítódás és a véralvadásgátlás szükségtelensége miatt a fiatal betegek minden tekintetben teljesen normális életmódot folytathatnak, de a Ross-műtét nem minden betegnél végezhető el biztonsággal.

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Studies on transition-metal picoline complexes

I. Preparation and thermoanalytical investigations

Journal of Thermal Analysis and Calorimetry
Authors: G. Liptay, A. Borbély-Kuszmann, and G. Nagy
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Although angiogenesis is considered to be indispensable for continuous tumour growth, only very few studies have been published performing microvessel quantification during tumour progression. We mea- sured the tumour vascularity in different stages of rat pancreatic carcinogenesis induced by azaserine and promoted by raw soya flour-containing pancreatotrophic diet. Besides the tumour samples taken at 6 (atypical acinar cell nodules), 15 (adenomas) and 20 (localised adenocarcinomas) months after carcino- gen initiation, we also investigated 3 control groups: tumour-bearing host tissue of azaserine-treated rats and normal tissue of untreated rats kept on standard or pancreatotrophic diet. In contrast with the usual microvessel counting on hot spots, we determined microvascular surface density (SV) and volume den- sity (VV) by electron microscopic morphometry. There was no significant difference in these respect between the control groups. At month 6 after the azaserine induction SV and VV showed slight, non- significant decrease as compared to the host control. Both values remained unchanged until the 15th month and increased significantly by the 20th month. These results may indicate comparable growth rate of tumour and new microvessels in the premalignant stages of carcinogenesis while a more intense angio- genesis than tumour growth afterwards.

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In order to target factors involved in plant-pathogen interactions, gene expression differences were investigated on pepper ( Capsicum annuum L.) plants after artificial infection with the bacterial pathogen Xanthomonas campestris pv. vesicatoria . Amplified Fragment Length Polymorphism investigations on reverse transcribed DNA fragments (cDNA-AFLP) were used to compare the expression profiles of parental lines and of resistant and susceptible individuals from pepper populations segregating for the gds gene, which confers a general defence system in pepper. In total, 73 transcript-derived fragments (TDFs) displaying differential expression patterns could be identified (presence-absence and/or different time courses in resistant and susceptible genotypes). Of these, 67 fragments were cloned and sequenced. In the case of several TDFs, sequence comparisons revealed close homologies to genes known to be responsible for abiotic stress or biotic elicitors, presenting potentially interesting targets for more detailed studies on gene expression and signal transduction.

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The aim of the present work was to study the soil seed bank of the semiarid sandy grassland community using the nested sampling procedure. The samples consisted of six concentric cores with diameters ranging from 5 to 22 cm and surface area ratio of the outermost to the innermost ring of 19. Investigations were directed to establish the minimum core diameter to find the dominant and less frequent species in the seed bank and also to have an insight on distribution patterns of species. The smallest core (diameter: 5 cm) employed in 20 repetitions was adequate to find the dominant species in the seed bank, while increasing the sample area to 19 times resulted in doubling the number of species found. The seeds of the dominant species had clustered distribution even at the smallest applied sample scale, while patterns of seed clumps followed different (uniform, contagious, random) distributions.

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The survey was carried out on the seed bank of several patches of an open, semiarid sandy grassland (Festucetum vaginatae Rapaics ex Soó 1929 (Borhidi 1996)). We chose four, approximately 20 m × 20 m large, adjacent patches, different in their species composition and total cover. Soil samples were taken in early spring and at the end of summer, in two consecutive years. We determined the seed bank of the samples with the seedling emergence method. The fact that we found the seeds of only two species that were not present in the vegetation indicates the isolated and without artificial disturbed state of the grassland. The vegetation and the seed bank of the patches showed a low degree of similarity in the same period, while the composition of the spring aspect reflected clearly in the seed bank of late summer in all four patches. Results showed that mosaic-like appearance is not only characteristic of the vegetation, but also the seed bank of the soil. Differentiation of the seed bank manifested mostly after the period of seed-fall, at the end of summer, while in early spring it was less expressed. On the basis of the differentiation of the seed bank we can conclude that not the dispersion of seeds, but natural vicinity of mother plants was decisive in forming the spatial variation of the seed bank.

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Abstract  

Simultaneous calorimetric and potentiometric/thermometric measurements were performed on three uncatalyzed bromate oscillators (UBOs) showing distinct temporal structures. The following UBOs were chosen: a) the gallic acid (3,4,5-trihydroxy benzoic acid)—bromate; b) the 1-hydroxy-4-[(1-hydroxy-2-methylamino)ethyl] benzene (HME)—bromate; and c) the 1,4-cyclohexanedione (CHD)—bromate system. Their oscillating reactions were monitored by an isoperibolic batch calorimeter of the Calvet-type at 20°C and with a quasi-adiabatic Dewar setup at room temperature, and in addition by platinum/calomel potentiometry and thermometry. Shape of the calorimetric curves, number and duration of the oscillations and their frequencies varied considerably between these three UBOs. The underlying chemical reaction schemes are discussed in connection with the energetic background.

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