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1.
Igor Loncaric Gabrielle L. Stalder Kemal Mehinagic Renate Rosengarten Franz Hoelzl Felix Knauer Chris Walzer 《PloS one》2013,8(12)
In order to test whether rooks (Corvus frugilegus) represent good indicators for the potential circulation of antibiotics in their native habitat, two populations with different migratory behavior were tested for the presence of beta-lactamase producing Enterobacteriaceae and methicillin-resistant Staphylococcus aureus (MRSA). In all, 54 and 102 samples of fresh feces of a migratory and a resident population were investigated. A total of 24 and 3 cefotaxime-resistant enterobacterial isolates were obtained from the migratory and resident population, respectively. In these isolates CTX-M-1 (n = 15), CTX-M-3 (n = 3), and CTX-M-15 (n = 3) genes were detected. TEM-1 and OXA-1 were associated with CTX-M in 3 and 2 isolates, respectively. In two E. coli isolates CMY-2 could be detected, where from one isolate displayed an overexpression of chromosomal AmpC as well. Among E. coli isolates the most common phylogenetic group was A (n = 11) and ST1683 (n = 5). In one E. coli of B2-ST131 the rfbO25b locus was detected. Three Enterobacter isolates were stably derepressed AmpC-producers. In five samples of the migratory population, PVL positive MRSA could be isolated. Two isolates were typed SCCmec IVa, spa type t127, and ST1. Three isolates carried a SCCmec type IVc, with spa type t852 and ST22. The highly significant difference of the occurrence of antibiotic resistance between the migratory population from eastern Europe compared to resident population in our study indicates that rooks may be good indicator species for the evaluation of environmental contamination with antibiotic resistant bacteria, especially due to their ecology, foraging behavior and differing migratory behavior. 相似文献
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Nimra Khan Dylan Pelletier Thomas S. McAlear Nathalie Croteau Simon Veyron Andrew N. Bayne Corbin Black Muneyoshi Ichikawa Ahmad Abdelzaher Zaki Khalifa Sami Chaaban Igor Kurinov Gary Brouhard Susanne Bechstedt Khanh Huy Bui Jean-François Trempe 《Structure (London, England : 1993)》2021,29(6):572-586.e6
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Summary Partial trisomy 11q due to a sporadic translocation was found in a mentally retarded girl with multiple abnormalities. The proportion of sporadic translocations involved in the total incidence of partial trisomies is discussed. 相似文献
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A I Gurevich A V Mikul'skis O V Nekrasova E A Chernen'kaia 《Molekuliarnaia genetika, mikrobiologiia i virusologiia》1988,(1):33-36
RecA-independent recombinations accompanying the processes of plasmids preparation and cloning into Escherichia coli cells are induced within the short direct and inverted repeats of several types. 相似文献
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The soybean trypsin inhibitor conjugate with a thermo-reactive water soluble polymer, poly(N-vinyl caprolactam), was successfully
used for thermally induced affinity precipitation of trypsin. The validity of the developed procedure was proven by a model
separation of trypsin from dilute solution containing a large excess of bovine serum albumin. 相似文献
9.
Igor A. Krasheninnikov Anton A. Komar Ivan A. Adzhubei 《Journal of Protein Chemistry》1991,10(5):445-453
Examination of nascent globin peptides accumulatingin vitro during globin synthesis in rabbit reticulocyte lysates was carried out. A view was supported that nonrandom distribution of codons with different usage frequencies in mRNA may determine the messenger's translation kinetics. Regions of reduced translation of - and -globin polypeptide chains were localized, and the cotranslational protein-folding model suggested previously was substantiated. An active conjunction of synthesis and folding of proteins was proposed as one of the main destinations of a translation nonuniformity. 相似文献
10.
Enhanced neuronal K+ conductance: a possible common mechanism for sedative-hypnotic drug action 总被引:2,自引:0,他引:2
P L Carlen N Gurevich M F Davies T J Blaxter M O'Beirne 《Canadian journal of physiology and pharmacology》1985,63(7):831-837
It is commonly thought that central nervous system depressant drugs exert their actions through enhancement of gamma-aminobutyrate (GABA)-mediated mechanisms. Recently, the cellular electrophysiological evidence from this laboratory and others suggests that both sedative hypnotics and general anaesthetics inhibit central neurons by increasing potassium conductance (GK). We have utilized the mammalian in vitro hippocampal and cerebellar slice preparations at 34-36 degrees C. Intracellular recordings from CA1, CA3, and cerebellar Purkinje cells were obtained. Low dose (sedative) concentrations of ethanol (less than or equal to 20 mM), two different benzodiazepines (midazolam and clonazepam in low nanomolar concentrations), and pentobarbital (10(-6) to 10(-4) M) were applied by pressure ejection or were bath perfused. All drugs caused a hyperpolarization with decreased spontaneous activity, and enhanced post spike afterhyperpolarizations (AHPs). These long-lasting AHPs are presumably due to enhanced calcium-mediated GK. Increased responsiveness to focally applied GABA was only seen at higher doses (ethanol, 100 mM; midazolam, 10(-7) M; pentobarbital, 10(-4) M). These data suggest that the above neurodepressant drugs, when applied at sedative doses to hippocampal pyramidal cells, enhance GK and not the actions of GABA. 相似文献