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Total fatty acids derived from 12 species of mushrooms were separated into fatty acid and 2-hydroxy fatty acid fractions (FA and HFA), and analyzed quantitatively. The HFA content varied from 0 to 22% of total fatty acids. The major fatty acids were 16:0, 18:0, 18:1, 18:2, and the major 2-hydroxy fatty acids were h16:0, h18:0, h22:0, h24:0. The predominant HFA in the mushrooms investigated had chain-lengths greater than 20 C-atoms, and were derived from sphingolipids — ceramides and cerebrosides.  相似文献   
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Soda pans are protected in the European Union as Natura 2000 areas in the category of “Pannonic saline steppes and marshes”. There are at least six soda pans of reference status in Serbia and only a half have strict legal protection. The number of similar, but disturbed (modified) habitats that could be reconstructed is still unknown. We conducted sampling in five natural and two disturbed soda pans aiming to compare a difference in physical and chemical water properties and benthic diatom communities. In addition, we tried to apply recently developed Diatom Index for Soda Pans (DISP) and Trait-based index (TBI) to test the applicability of taxonomic and trait-based approaches in ecological status assessment of soda pans in the southern part of the Carpathian Basin. In contrast to natural soda pans, lower pH and nutrients levels were recorded in disturbed pans. A total of 86 taxa of benthic diatoms, including 11 new for diatom flora of Serbia, were identified. A lower species richness and Shannon index was recorded in natural soda pans. Nitzschia austriaca, N. supralitorea, Navicula veneta and N. wiesneri were dominant diatoms in soda pans of the reference status. Both diatom indices were in average lower in disturbed pans, and this difference was statistically significant for DISP index. We concluded that two indices, supplemented with indicator values for some local diatom species, can be a promising tool for soda pan conservation in this part of the Carpathian Basin.

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The heterogeneity of the ultramafic vegetation of the Central Balkans is rather great. Although this vegetation has been continuously investigated, some gaps are still to be filled. For example, the lack of available data on ultramafic vegetation of the Republic of Macedonia is evident. In that light, we have investigated different relic Stipa species-dominated dry grasslands over ultramafic bedrock. Twenty relevés were made and compared to the similar vegetation types (i.e. Potentilla visianii, Centaureo kosaninii-Bromion fibrosi, “Thymion jankae”, Saturejo-Thymion and Alyssion heldreichii) by means of numerical analyses. We distinguished one new association and one informal community, providing them with diagnosis and lists of diagnostic, constant and dominant species. We also determined their syntaxonomic positions and relations to ultramafic syntaxa from the neighboring countries.  相似文献   
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Suspension culture was more efficient method for haploid production than anther culture. All analysed androgenic regenerants originating from embryogenic microspores in suspension culture of Aesculus hippocastanum L. had a haploid number of chromosomes (n=20), while 50 % of those derived from anther culture were diploids. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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In vitro culture of Chenopodium murale L. (ecotype 197) green and herbicide SAN 9789 - treated "white" plants was established and the effects of benzylaminopurine (BAP), indole-3-acetic acid (IAA) and gibberellic acid (GA3) on growth and flowering were tested. Green plants did not flower on glucose free media, while 17 % of plants flowered on 5 % glucose-containing medium. SAN 9789 (10–5 M) inhibited growth and flowering. BAP and IAA (0.1 – 5 mg dm–3) also inhibited growth and flowering of green and "white" plants. GA3 (10 mg dm–3) stimulated leaf development in green plants, but had no significant effect on "white" plants, and stimulated flowering of green (41 %) and "white" (33 %) plants.  相似文献   
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The aphantochilid spider Aphanlochilus rogersi accurately mimics black ants of tribe Cephalotini, and is commonly found in the neighbourhood of its models' nests. The mimic seems to be a specialized predator of this type of ant, rejecting any insect offered as prey other than cephalotines. In the field, A. rogersi was observed preying on the model species Zacryptocerus pusillus. In captivity, the spider preyed on the models Z. pusillus and Z. depressus, as well as on the yellow non-model Z. clypeatus. Recognition of correct prey by A. rogersi appears to be based primarily on visual and tactile stimuli. Capturing ant prey from behind was the most common attack tactic observed in A. rogersi, and is probably safer than frontal attacks, as in this case the spider can be bitten on the legs before the ant is immobilized. Aphanlochilus rogersi, when feeding on the hard-bodied ant models, uses the ant corpses as a ‘protective shield’ against patrolling ants of the victim's colony and resembles an ant carrying a dead companion. Certain types of mimetic traits in A. rogersi (close similarity to ant models in integument texture and pilosity of body and legs), together with ‘shielding behaviour’, are thought to function as ant-deceivers, facilitating the obligatory intimate contact the mimic must make with cephalotines in order to capture a prey among other ants. The close similarity in the arrangement of dorsal spines, body shape, integument brightness and locomotion, together with antennal illusion, is regarded as a strategy of A. rogersi for deceiving visually-hunting predators that avoid its sharp spined ant models. It is proposed that ant-mimicry in A. rogersi has both an aggressive and a Batesian adaptive component, and evolved as a result of combined selective pressures exerted both by Cephalotini ant models (through defensive behaviour towards the mimics which attack them) and predators that avoid cephalotines (through predatory behaviour toward imperfect mimics). This suggestion is schematized and discussed in terms of two tripartite mimicry systems.  相似文献   
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Aims: The aim of this study was to explore the occurrence of methicillin‐resistant staphylococci in a large urban public transport system. Methods and Results: Samples were taken from hand rails, which passengers hold onto when they are standing. In total, 1400 swabs taken from 55 vehicles (trolleybuses, trams and buses) were examined. As many as 30·1% samples were positive for the presence of methicillin‐resistant coagulase‐negative staphylococci (MRCoNS), but none for methicillin‐resistant Staphylococcus aureus (MRSA). MRCoNS were isolated from all 55 vehicles. Nearly 50% of MRCoNS isolates displayed resistance not only to beta‐lactams, but at least to two or more other classes of antimicrobials as well. Conclusions: This study demonstrated widespread occurrence of MRCoNS on hand rails in public transport vehicles. MRSA was not detected. Significance and Impact of the Study: The recovery of methicillin‐resistant staphylococci from public transport system implies a potential risk for transmission of these bacteria in an out‐hospital environment.  相似文献   
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