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Lucia Westrich Silvie Domann Bettina Faust David Bedford David A Hopwood reas Bechthold 《FEMS microbiology letters》1999,170(2):381-387
From a cosmid library of Streptomyces cyanogenus S136, DNA fragments encompassing approximately 35 kb of the presumed landomycin biosynthetic gene cluster were identified and sequenced, revealing 32 open reading frames most of which could be assigned through data base comparison. 相似文献
103.
Anett Geyer reas Roth Stephan Vettermann Elisabeth Günther Annemarie Groh Eberhard Straube Karl-Hermann Schmidt 《FEMS immunology and medical microbiology》1999,26(1):11-24
Besides group A (GAS), Lancefield group C beta-haemolytic streptococci (GCS) have been implicated as a causative agent in outbreaks of purulent pharyngitis. In this study we have investigated a class CI M protein of a Streptococcus dysgalactiae1:256, revealed that 26% of these sera showed serological cross-reactivity between a 68-kDa cartilage protein and the N-terminal part of MC. Only 8% of the sera of healthy patients showed this property. In additional, MC also cross-reacted with antibodies recognising epidermal keratins. The cross-reacting 68-kDa protein from cartilage was different from human serum albumin, but was recognised with anti-vimentin immune serum. The MC was cloned and the gene sequenced. By using PCR, recombinant gene fragments encoding characteristic peptide fragments of MC were expressed in Escherichia coli. The peptides were used to map the binding sites for plasma proteins and to locate the cross-reacting epitopes on the MC molecule. In consequence, sequence alignments revealed that MC shared homologous regions with vimentin and different keratins. Our data, obtained with MC, suggest that not only infections with GAS but also infections with GCS and possibly GGS (the latter species can also produce class CI M-like proteins) may be responsible for the formation of streptococcal-associated sequel diseases. 相似文献
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Data about the bionomics of the pollen wasp Ceramius palaestinensis (Giordani Soika, 1957) are presented for the first time. Ceramius palaestinensis is characterized by the following ethological elements: (i) the nest is excavated in non-friable soil; (ii) the burrow is surmounted by a turret from earth extracted from within the burrow; (iii) the nest is possibly perennial; (iv) the nest has a relatively short, vertical to sub-vertical main shaft with an expansion at the bottom; (v) the main shaft is not terminated by a cell; (vi) secondary shafts are absent; (vii) the cells are sub-horizontal, all at different depths; (viii) brood cells are constructed mud-cells built within an excavated cell, formed from earth excavated within the burrow; (ix) imagines visit only flowers of Trifolium (Fabaceae) and brood cells are provisioned exclusively with pollen from this plant genus; Trifolium species varying considerably in inflorescence morphology lead to different positions of foraging wasps on the inflorescences during flower visits; Trifolium resupinatum or T. clusii inflorescences with resupinate flowers function as a disc-shaped pseudanthium with the vexilla of the flowers arranged on the outer periphery serving as petal-like exhibition organs; and (x) males patrol and perch at water collection sites, at flowers and within nesting aggregations; copulations or copulatory attempts are observed there. 相似文献
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ümit Aydin Johannes Vorwerk Matthias Dümpelmann Philipp Küpper Harald Kugel Marcel Heers J?rg Wellmer Christoph Kellinghaus Jens Haueisen Stefan Rampp Hermann Stefan Carsten H. Wolters 《PloS one》2015,10(3)
We investigated two important means for improving source reconstruction in presurgical epilepsy diagnosis. The first investigation is about the optimal choice of the number of epileptic spikes in averaging to (1) sufficiently reduce the noise bias for an accurate determination of the center of gravity of the epileptic activity and (2) still get an estimation of the extent of the irritative zone. The second study focuses on the differences in single modality EEG (80-electrodes) or MEG (275-gradiometers) and especially on the benefits of combined EEG/MEG (EMEG) source analysis. Both investigations were validated with simultaneous stereo-EEG (sEEG) (167-contacts) and low-density EEG (ldEEG) (21-electrodes). To account for the different sensitivity profiles of EEG and MEG, we constructed a six-compartment finite element head model with anisotropic white matter conductivity, and calibrated the skull conductivity via somatosensory evoked responses. Our results show that, unlike single modality EEG or MEG, combined EMEG uses the complementary information of both modalities and thereby allows accurate source reconstructions also at early instants in time (epileptic spike onset), i.e., time points with low SNR, which are not yet subject to propagation and thus supposed to be closer to the origin of the epileptic activity. EMEG is furthermore able to reveal the propagation pathway at later time points in agreement with sEEG, while EEG or MEG alone reconstructed only parts of it. Subaveraging provides important and accurate information about both the center of gravity and the extent of the epileptogenic tissue that neither single nor grand-averaged spike localizations can supply. 相似文献
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