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51.
To evaluate the prevalence rate of tick-borne bacterial pathogens, unfed adult Ixodes ricinus ticks were collected from vegetation in 2001, 2003, and 2004 at 18 localities throughout Serbia. A total of 287 ticks were examined by PCR technique for the presence of Borrelia burgdorferi sensu lato, Anaplasma phagocytophilum, and Francisella tularensis. The highest prevalence rate was that for B. burgdorferi sensu lato (42.5%), followed by A. phagocytophilum (13.9%) and F. tularensis (3.8%). The presence of five B. burgdorferi sensu lato genospecies, namely, B. burgdorferi sensu stricto, B. afzelii, B. garinii, B. lusitaniae, and B. valaisiana was identified by restriction fragment length polymorphism (RFLP) analysis. The most frequent B. burgdorferi sensu lato genospecies was B. lusitaniae, followed by B. burgdorferi sensu stricto. Co-infection by B. burgdorferi sensu stricto and B. lusitaniae was frequently observed. Co-infection by B. burgdorferi sensu lato and A. phagocytophilum and co-infection by B. burgdorferi sensu lato and F. tularensis appeared in 24 ticks. Sequencing of p44/msp2 paralogs of Serbian A. phagocytophilum showed that they were unique and distinct from those of A. phagocytophilum in US and UK. This is the first report of B. garinii, B. lusitaniae, B. valaisiana, as well as A. phagocytophilum and F. tularensis infected ticks in Serbia. These findings indicate a public health threat in Serbia of tick-borne diseases caused by B. burgdorferi sensu lato, A. phagocytophilum and F. tularensis.  相似文献   
52.
Wetlands Ecology and Management - Massive gravel excavation is one of the most destructive forces affecting riverine habitats in Europe. However, gravel pit lakes are also recognized as valuable...  相似文献   
53.
Three closely related [MoO2(L)(ML)] complexes, where L is the 2-hydroxy-1-naphthaldehyde-S-methylisothiosemicarbazone ligand, and ML is EtOH (I), Py (II) and DMSO (III), were synthesized, characterized by NMR and IR spectra, and their X-ray crystal structures were determined. The crystal structure properties of these three closely related complexes were compared. Two cis-Mo-O bond lengths were almost the same in the crystal structure of complexes II and III, while in complex I a significant difference between the two cis-Mo-O bond lengths was observed. At the same time, the geometry of L ligand in complex I is different, compared to II and III. DFT calculations on the isolated molecule I, as well as geometrical analysis of the complexes indicate that intramolecular interactions are not responsible for these structural differences. On the other hand, the pattern of intermolecular contacts in the crystal structure of I differs from those observed in II and III. Analyses indicate that differences in cis-Mo-O bond lengths and in the geometry of ligand L could be related to intermolecular interactions. These results suggest the possibility that in enzymes oxotransferases or in their model systems, the Mo-O bond length could be designed by the interactions of chelate ligands with the surroundings.  相似文献   
54.
Searching structures of porphyrin-containing proteins from the Protein Data Bank revealed that the π system of every porphyrin ring is involved in XH/π interactions, with most of the porphyrins having several interactions. Both five-membered pyrrole rings and six-membered chelate rings are involved in XH/π interactions; the number of interactions with five-membered rings is larger than the number of interactions with six-membered rings. We found interactions with C–H and N–H groups as hydrogen-atom donors; however, the number of CH/π interactions is much larger than the number of NH/π interactions. The amino acids involved in the interactions show a high conservation score. Our results that every porphyrin is involved in XH/π interactions and that amino acids involved in these interactions are highly conserved demonstrate that XH/π interactions play an important role in porphyrin–protein stability. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
55.
Stipa crassiculmis subsp. picentina Martinovský, Moraldo & Caputo (Poaceae, Pooideae, Stipae) was found for the first time in the Balkan Peninsula. It was recorded in the northern part of the Republic of Macedonia, in the P?inja River gorge (Badar Gorge), between Veles and Katlanovo on ultramafic substrates. To date, S. crassiculmis subsp. picentina was known only for Italy where it occurs in the Lombardy and Campania administrative regions. This record for the Balkan Peninsula is a new example of Amphi-Adriatic Balkan-Apennine disjunction. In this paper, the morphological and anatomical characters of the specimens collected in the study area were reported together with the phytosociological characteristics of the habitat. The threatened status of the species for Macedonia was also assessed on the basis of the IUCN criteria.  相似文献   
56.
57.
Paramphistomum parasites identified by histology as Paramphistomum microbothrium were found in 18 of 34 roe deer (Capreolus capreolus) intestines from central Serbia, examined between 1998 and 2004. This represents the first record of P. microbothrium in roe deer in Serbia.  相似文献   
58.
The spontaneously active Br neuron from the brain-subesophageal ganglion complex of the garden snail Helix pomatia rhythmically generates regular bursts of action potentials with quiescent intervals accompanied by slow oscillations of membrane potential. We examined the involvement of the Na(+)/K(+) pump in modulating its bursting activity by applying a static magnetic field. Whole snail brains and Br neuron were exposed to the 10-mT static magnetic field for 15?min. Biochemical data showed that Na(+)/K(+)-ATPase activity increased almost twofold after exposure of snail brains to the static magnetic field. Similarly, (31)P NMR data revealed a trend of increasing ATP consumption and increase in intracellular pH mediated by the Na(+)/H(+) exchanger in snail brains exposed to the static magnetic field. Importantly, current clamp recordings from the Br neuron confirmed the increase in activity of the Na(+)/K(+) pump after exposure to the static magnetic field, as the magnitude of ouabain's effect measured on the membrane resting potential, action potential, and interspike interval duration was higher in neurons exposed to the magnetic field. Metabolic pathways through which the magnetic field influenced the Na(+)/K(+) pump could involve phosphorylation and dephosphorylation, as blocking these processes abolished the effect of the static magnetic field.  相似文献   
59.
Stimulated erythropoiesis and reticulocytosis can be induced by daily bleeding, or by phenylhydrazine (PHZ) treatment. We compared the in vivo effects of PHZ and bleeding treatment on haematological, energy and redox status parameters in red blood cells (RBC) of rats. The results showed that all followed haematological parameters were significantly lower in bleeding, compared to PHZ-treated rats. PHZ induced even 2.58-fold higher reticulocytosis as compared to bleeding treatment. Although PHZ induced higher reticulocytosis, respiration intensity and energy production was lower than in bleeding-induced reticulocytes. These alterations were the consequence of increased superoxide anion and peroxynitrite concentrations in PHZ-treated rats. Bleeding treatment resulted in increased activity of an antioxidative enzyme, superoxide dismutase. In conclusion, differences in these two experimental models for reticulocytosis may be used as tools for appropriate pharmacological testing of redox-active substances considering energy and redox processes, as well as apoptosis pathways.  相似文献   
60.
An integrative taxonomic approach revealed two taxa within Chrysotoxum festivum (Linnaeus, 1758) (Diptera, Syrphidae), C. festivum A and C. festivum B. In addition to morphological differences, results also showed significant distinction in geometric morphometrics of wings and surstyli, and in DNA sequence data (nuclear ITS2 sequences) between C. festivum A, C. festivum B, and the closely related species C. elegans Loew, 1841. From examination of type material, the name C. tomentosum Giglio‐Tos, 1890 is proposed for C. festivum B, and the taxon is redefined. © 2013 The Linnean Society of London  相似文献   
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