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排序方式: 共有274条查询结果,搜索用时 15 毫秒
1.
Dr. Adarshi P. Welegedara Dr. Ansis Maleckis Ruchira Bandara Dr. Mithun C. Mahawaththa Iresha Dilhani Herath Yi Jiun Tan Dr. Angeliki Giannoulis Prof. Daniella Goldfarb Prof. Gottfried Otting Prof. Thomas Huber 《Chembiochem : a European journal of chemical biology》2021,22(8):1480-1486
The selenol group of selenocysteine is much more nucleophilic than the thiol group of cysteine. Selenocysteine residues in proteins thus offer reactive points for rapid post-translational modification. Herein, we show that selenoproteins can be expressed in high yield and purity by cell-free protein synthesis by global substitution of cysteine by selenocysteine. Complete alkylation of solvent-exposed selenocysteine residues was achieved in 10 minutes with 4-chloromethylene dipicolinic acid (4Cl-MDPA) under conditions that left cysteine residues unchanged even after overnight incubation. GdIII−GdIII distances measured by double electron–electron resonance (DEER) experiments of maltose binding protein (MBP) containing two selenocysteine residues tagged with 4Cl-MDPA-GdIII were indistinguishable from GdIII−GdIII distances measured of MBP containing cysteine reacted with 4Br-MDPA tags. 相似文献
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The barrier function, surface biochemistry, and morphology of confluent monolayers of endothelial cells isolated from different segments of the bovine lung vasculature [microvessels (BLMVEC), vein (BPVEC) and artery (BPAEC)] were grown in culture and compared. A number of common cell surface proteins were identified along with two proteins of 46 and 48 kDa found exclusively on BPVEC. Lectin affinity chromatography revealed multiple glycosylation differences. The lectins, Arachis hypogaea (AHA) and Lycopersicum esculentum (LEA) agglutinins, interacted with several glycoproteins of BLMVEC but not of BPAEC. Bandeiraea simplicifolia (BS-1) and Caragana arborescens (CAA) agglutinins recognized several glycoproteins of BPVEC and BPAEC but not BLMVEC. Permeabilities were much lower for BLMVEC than BPAEC or BPVEC monolayers, with a range of about 16-fold less for sucrose to 2-fold less for albumin. Electron microscopy revealed that BLMVEC have a greater surface density of plasmalemmal vesicles (approximately 4-fold) and more extensively developed intercellular junctions with more focal membrane adhesion sites per junction (approximately 9-fold) than the other cells. We conclude that: i) BLMVEC monolayers form a much more restrictive barrier to molecular transport as a result of the tighter junctional formation; and ii) endothelial surface glycoproteins may be differentially glycosylated depending on their segmental location within the vasculature. 相似文献
4.
Of 101 women, 15-50 years of age, presenting with vaginal discharge, 34 had bacterial vaginosis and were randomly assigned to a seven-day course of oral treatment with either erythromycin (0.5 g b.i.d.) or metronidazole (0.4 g b.i.d.) in a single-blind, cross-over study. Treatment failure (> or = three clinical signs of bacterial vaginosis) occurred in 13 (81%) of 16 patients given erythromycin, as compared with three (17%) of 18 women treated with metronidazole (p < 0.001). Persistence of Gardnerella vaginalis, Mobiluncus species and/or Mycoplasma hominis was found in 14 of 16 patients treated with erythromycin, and in four of 16 patients treated with metronidazole. Treatment with metronidazole was successful (< or = two clinical signs of bacterial vaginosis) in eight of 10 cases of erythromycin treatment failure. Neither of two cases of metronidazole treatment failure was cured with erythromycin. At three-month follow-up of 31 women, persistence or recurrence of bacterial vaginosis was diagnosed in 11 cases (36%). 相似文献
5.
Gottfried Spicher 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1987,184(4):300-303
Zusammenfassung Es wurden Untersuchungen angestellt über die Mikroflora von 26 Weizensauerteigen für die Panettone- und Weizenbrotherstellung aus Bäckereien in Italien, der Schweiz, Deutschland und Schweden. Die Sauerteige wurden teils mit einem Spontansauer angestellt, teils mit einem reifen Weizensauer (masa madre), der bereits über längere Zeit fortgeführt wurde. Die Mikroflora der Sauerteige (pH 4,4 bis 3,8, Säuregrad 6,3 bis 22,4) setzte sich aus 2,5 × 105 bis 3 × 109 Lactobacillun/g und 1 × 103 bis 4,5 × 107 Hefen/g zusammen. Es wurden insgesamt 388 Isolate gewonnen und als Vertreter der GattungLactobacillus identifiziert. In Weizensauerteigen, die mit einem Spontansauer angestellt wurden, traten vornehmlich homofermentativeLactobacillus-Species auf (Lactobacillus plantarum, L. casei, L. farciminis, L. homohiochii), nebenL. brevis, L. hildegardii und einigen anderen heterofermentativen Spezies. Die Sauerteigbakterien des mit einem masa madre angestellten Weizensauerteig erwiesen sich insbesondere alsLactobacillus brevis ssp.lindneri resp.L. sanfrancisco, nebenL. brevis, L. hildegardii undL. viridescens. Daneben kamen in den Weizensauerteigen zu mehr oder minder hohen AnteilenStreptococcus spp. vor. Bei den im Weizensauerteig auftretenden Hefen handelt es sich umSaccharomyces cerevisiae, nebenS. servazzi undCandida milleri.
Nr. 5475 der Veröffentlichung der Bundesforschungsanstalt für Getreide- und Kartoffelverarbeitung, Detmold 相似文献
The microflora of sourdoughXXII. Communication: The lactobacillus species of wheat sourdough
Summary We investigated the microflora of 26 wheat sourdoughs which are used for the production of panettone and wheat bread in bakeries in Italy, Switzerland, Germany and Sweden. The sourdoughs were started in part with a ripe wheat sour (masa madre) which had been propagated for a long time. The microflora of the wheat sourdough (pH 4.4 to 3.8; acidity 6.3 to 22.4) consisted of 2 × 105 to 3 × 109 lactobacilli/g and 1 × 103 to 4.5 to 107 yeasts/g. We obtained 388 isolates; all belonging to the genusLactobacillus. In wheat sourdoughs which were started with a spontaneous sour homofermentativelactobacilli (Lactobacillus plantarum, L. casei, L. farciminis, L. homohiochii) are mainly found and alsoLactobacillus brevis, L. hildegardii and some other heterofermentative species. The main sourdough bacteria of wheat sourdoughs which were prepared with a masa madre were identified asLactobacillus brevis ssp.lindneri resp.L. sanfrancisco, which were present in addition toL. brevis, L. hildegardii, andL. viridescens. We also found varying numbers ofStreptococcus spp. in the wheat sourdoughs. The yeasts which we identified wereSaccharomyces cerevisiae, S. servazzi andCandida milleri.
Nr. 5475 der Veröffentlichung der Bundesforschungsanstalt für Getreide- und Kartoffelverarbeitung, Detmold 相似文献
6.
Roland Schmidt Ulrich Hammon Stefan Gottfried M. Bruce Welch Helmut G. Alt 《应用聚合物科学杂志》2003,88(2):476-482
The synthesis of iron(II) complexes with various tridentate di(imino)pyridine ligands and their potential as ethene oligomerization catalysts are described. The ligands are characterized by 1H‐ and 13C‐NMR spectroscopy and the complexes only by mass spectrometry due to their paramagnetism. After activation either with methylalumoxane (MAO) or with a heterogeneous cocatalyst consisting of partially hydrolyzed trimethylaluminum and silica gel, the prepared complexes proved to be good catalysts for the oligomerization of ethene. 1‐Octene, 1‐hexene, and 1‐decene were the major products, formed in very high isomeric purity (99.9 %). © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 476–482, 2003 相似文献
7.
Ira S. Gottfried 《Information Systems Management》2013,30(2):86-89
The importance of securing data against the threat of natural disasters i s something most MIS managers don't realize until it's too late. This column describes how two fires and an earthquake adversely affected several companies that were unprepared, or only partially prepared, for such disasters. It also discusses disaster recovery measures some MIS executives believe their companies should strengthen not only to protect the data center but to reduce their employees risk of losing valuable informa- tion from office files. 相似文献
8.
Gorka Epelde Eduardo Carrasco Gottfried Zimmermann Jan Alexandersson Robert Neßelrath Markus Dubielzig 《Universal Access in the Information Society》2013,12(1):73-87
This paper presents a new approach to make current and future television universally accessible. The proposed approach provides a means of universal accessibility both for remotely operating the TV set and for interacting with online services delivered through the TV. This proposal is based on the ISO/IEC 24752 “Universal Remote Console” (URC) standard. This standard defines an abstract user interface layer called the “user interface socket” and allows the development of pluggable (plug-in) user interfaces for any type of user and any control device. The proposed approach lays the foundation for the development of advanced user interfaces that can be interacted within various modalities. Different prototypes have been developed based on this approach and tested with end users. The user tests have shown this approach to be a viable option for the proposed scenarios. Based on the experience gathered with the prototypes, recommendations and implementation options are suggested for commercial adoption. 相似文献
9.
Christian Schuberth Peter Singerl Michael E. Gadringer Holger Arthaber Andreas Wiesbauer Gottfried Magerl 《国际射频与微波计算机辅助工程杂志》2010,20(4):446-457
This article presents a switched‐mode transmitter architecture using a current mode class‐D (CMCD) amplifier. To achieve high average efficiency for a modulated signal the envelope of the complex baseband signal is transformed into pulses such that the CMCD amplifier is operated either at its peak efficiency or completely switched off. The CMCD amplifier has been designed based on single‐tone active harmonic load‐pull measurements to achieve a power‐added efficiency (PAE) of 61.5% with 25 W output power at 900 MHz using LDMOS FETs. Removing the losses of the demodulation filter and of the amplifier a 10% higher efficiency than in an ideal class‐B amplifier can be obtained for burst‐mode operation with a peak‐to‐average power ratio of 10 dB. © 2010 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2010. 相似文献
10.
The use of RFID middleware to support application development for and integration of RFID hardware into information systems
has become quite common in RFID applications where reader devices remain stationary, which currently represents the largest
part of all RFID applications in use. Another field for applying RFID technology which is offering a huge set of novel possibilities
and applications are mobile applications, where readers are no longer fixed. In order to address the specific issues of mobile RFID-enabled applications
and to support developers in rapid application development, we present ID-Services, an architecture for an RFID middleware that is designed to support mobile applications. The ID-Services approach has been used to implement MoVIS (Mobile Visitor Information System), a mobile application which allows museum visitors to request individually adapted multimedia
information about exhibits in an intuitive way. 相似文献