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1.
A simple and sensitive high-performance liquid chromatography method with electrochemical detector is described for the determination of free 3-methoxy-4-hydroxyphenylacetic acid (HVA) in human plasma. The method does not involve any extraction, is specific and reproducible, and has the potential to measure serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) simultaneously. The plasma concentration of free HVA in eight normal, healthy adult volunteers was 10.9 ± 4.6 (mean ± SD). In a preliminary study, in one schizophrenic patient the plasma HVA increased twofold after neuroleptic treatment.  相似文献   
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Wood-pastures are fragile ecosystems because they were formed by, and depend on specific, low-intensity multifunctional management. Although their ecological and cultural significance is high, wood-pastures are rapidly deteriorating all over Europe, mainly due to changing land use. We still lack a basic understanding of the ecological value of wood-pastures, and in which features they differ from other landscape elements. In this paper we investigated the ecological value of wood-pastures for passerine birds by (i) comparing bird assemblages of wood-pastures with those of closed forests and open pastures and (ii) exploring the relationships between variables describing wood-pastures and species traits of the bird assemblages. Our study region (Southern Transylvania, Romania) provides a unique opportunity to understand the importance of a traditional cultural and ecological environment for many different organisms. Wood-pastures had a higher overall number of bird species, and a higher spatial turnover in bird community composition than closed forests and open pastures. We found significant associations between bird species traits and habitat structural elements in wood-pastures such as large trees, oak- and pear trees and shrubs. Our findings suggest that traditional wood-pastures in Southern Transylvania have distinct and rich passerine bird communities. This richness is inextricably linked to the multifunctional, low-intensity land use traditionally applied in the wood-pastures that promotes high niche diversity. For effective conservation of the biodiversity of wood-pastures, a detailed understanding is needed of how different management regimes may influence the key structural elements of wood-pastures relevant for biodiversity and these should be protected.  相似文献   
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The European endemic Erebia oeme (Hübner [1804]) (Lepidoptera: Nymphalidae: Satyrinae) is discovered in the Carpathian Chain, from where it was considered to be absent. The single population found is situated in the southern part of the Romanian Carpathians (Retezat Mountains), where it flies sympatrically and synchronically with Erebia medusa ([Denis & Schiffermüller] 1775). The similar external morphology of these two species probably caused E. oeme to be overlooked in the Carpathians, leading to an unexpected information gap in the otherwise thoroughly studied European continent. The morphology of the Romanian specimens is compared to populations from the rest of the species’ range and to E. medusa. In addition, we tested DNA barcoding as a method to discriminate between these species and confirmed that it represents an effective identification tool for the taxa involved. The habitat of E. oeme, adults of both sexes and their genitalia are illustrated in comparison with E. medusa. Based on the study of several collections, we show that E. oeme is likely to be extremely local in the Carpathians and provide arguments to consider the species as vulnerable in Romania.  相似文献   
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Ioan I. Bucur 《Facies》2007,53(3):377-388
A new dasycladalean alga Salpingoporella? popgrigorei n. sp. was identified in P?durea Craiului Mountains (northern Apuseni, Romania) in the Lower Aptian limestone of the Valea Bobdei Member. The new alga was found within the external platform coarse bioclastic facies with fragments of corals, sclerosponges, bivalves (including rudists), gastropods, echinoderms, brachiopods, and bryozoans. The micropaleontological assemblage consists of foraminifera, calcareous algae, rare rivulariacean-type cyanobacteria, and some problematic microfossils. The deposits are Early Bedoulian in age, as clearly indicated by the orbitolinid foraminifera Orbitolinopsis pygmaea, Paracoskinolina sunnilandensis and Palorbitolina lenticularis. Salpingoporella? popgrigorei n. sp. is a medium-sized dasycladalean alga showing funnel-like laterals with an euspondyl arrangement. The laterals consist of two distinctive parts. The proximal part is narrow and flattened. The distal part widens relatively suddenly, and then narrows slightly before the final widening towards the exterior, in the place where the laterals most probably formed an assimilatory cortex. The distinctive features of the new species are represented by the shape of the laterals. The new Salpingoporella best resembles the Upper Hauterivian–Lower Barremian p.p. Salpingoporella genevensis (Conrad), especially due to the quadrangular aspect of the laterals in middle-deep tangential section. However, differences refer to the laterals’ general shape, and to the typical features of the laterals in deep tangential section of Salpingoporella? popgrigorei n. sp.  相似文献   
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Question: What is the variation in species composition of Central European semi‐dry grasslands? Can we apply a training‐and‐test validation approach for identifying phytosociological associations which are floristically well defined in a broad geographic comparison; can we separate them from earlier described associations with only a local validity? Location: A 1200 km long transect running along a gradient of increasing continentality from central Germany via Czech Republic, Slovakia, NE Austria, Hungary to NW Romania. Methods: Relevés with > 25% cover of Brachypodium pin‐natum and/or Bromus erectus were geographically selected from a larger database. They were randomly split into two data sets, TRAINING and TEST, each with 422 relevés. Cluster analysis was performed for each data set on scores from significant principal coordinates. Different partitions of the TRAINING data set were validated on the TEST data set, using a new method based on the comparison of % frequencies of species occurrence in clusters. Clusters were characterized by statistically defined groups of diagnostic species and values of climatic variables. Results: Species composition changed along the NW‐SE gradient and valid clusters were geographically well separated. Optimal partition level was at 11 clusters, six being valid: two clusters Germany and the Czech Republic corresponded to the Bromion erecti; two clusters from the Czech Republic and Hungary to the Cirsio‐Brachypodion, and two clusters were transitional between these two alliances. Conclusion: The training‐and‐test validation method used in this paper proved to be efficient for discriminating between robust clusters, which are appropriate candidates for inclusion in the national or regional syntaxonomic overviews, and weak clusters, which are specific to the particular classification of the given data set.  相似文献   
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New chromosome numbers for two species from the Senecio nemorensis group: S. dacicus (2n = 40) and S. ucranicus (2n = 40) have been ascertained. The counts for S. germanicus Wallr. subsp. germanicus (2n = 40), S. hercynicus Herborg subsp. hercynicus (2n = 40), S. ovatus (P. Gaertn. et al.) Willd. subsp. ovatus (2n = 40) occurring in the Carpathians are also reported. The study confirmed only the known tetraploid chromosome number for the taxa of this group. The pollen fertility ranged from 82.09 to 92.99% in all examined species and subspecies, including their hybrids.  相似文献   
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In 1905, Nopcsa tentatively identified a fragmentary rib from the Jibou Formation at Someş Odorhei as belonging to an ornithopod dinosaur. Therefore, he concluded that the base of this formation is Late Cretaceous, but this hypothesis was subsequently ignored or rejected by other authors. New dinosaur bones discovered in this locality by new excavations are here interpreted as belonging to the euornithopod Zalmoxes shqiperorum Weishampel, Jianu, Csiki and Norman, 2003. The base of the Jibou Formation can therefore be regarded as Maastrichtian, correlative to the Sânpetru Formation and to the middle member of the Densuş Ciula Formation from the Haţeg Basin, as well as the base of the Şard Formation in the southwestern Basin of Transylvania, in the Alba Iulia area. The presence of Zalmoxes at Someş Odorhei also confirms the northeastern extension for the ‘Haţeg Island’ in Transylvania.  相似文献   
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A high-resolution pollen analysis has been carried out on the Lupoaia section (SW Romania) in order to check whether the repetitive clay–lignite alternations correspond to cyclic changes in climate. Increases in altitudinal tree pollen content appear to have been caused by drops in temperature, while developments of thermophilous elements correspond to rises in temperature, still under humid conditions. Such repeated changes in vegetation, on the whole consistent with the clay–lignite alternations, have been forced by cycles in eccentricity. On the basis of a comparison between the Lupoaia pollen record and (1) European climatostratigraphy (based on reference pollen diagrams documenting global changes), and (2) global climatic curves (eccentricity, δ18O), the age of the section has been reconsidered. The Lupoaia section (i.e. from lignite IV to lignite XIII) starts just before the C3n.3n Chron and probably ends just before the C3n.1n Chron. The section represents a time span of about 600 kyr, i.e. from about 4.90 Ma to about 4.30 Ma.  相似文献   
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