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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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N A Medvedeva T C Vo I Iu Sergeev I M Rodionov 《Biulleten' eksperimental'no? biologii i meditsiny》1987,103(5):517-520
Neuromediated behaviour of feline caudal femoral arteries was studied in vitro. Transmural stimulation of arteries, previously constricted by noradrenaline, caused an up to 58% relaxation of the induced tone. Atropine (10(-5) g/ml) blocked this response by 93%. The removal of endothelium did not affect the magnitude of the response. It is suggested that the caudal femoral artery is an example of a blood vessel which has muscarinic receptors located directly on its smooth muscles. 相似文献
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L V Lyzlova B L Vo?tsekhovski? K B Grabovskaia A A Totolian 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1989,(7):7-12
The work shows that fibronectin obtained from human plasma is capable of binding with streptococci of different groups with almost equal effectiveness. Fibronectin bound to bacterial cells inhibits the adhesion of group A streptococci onto vaginal cells, but it produces no effect on the adhesion of group B streptococci. The binding constant of fibronectin 125I is equal to 10(6) -M-1, which indicates that the level of the specificity of interaction is not sufficiently high. 相似文献
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A V Paniutich B I Rubika?te N N Vo?tenok E A Shidlovskaia S L Grokhovski? A L Zhuze O O Favorova 《Bioorganicheskaia khimiia》1989,15(8):1060-1069
The importance of protein phosphorylation at tyrosyl hydroxy groups in the control of cell proliferation has recently been established. For identification of tyrosine-phosphorylated proteins, monoclonal antibodies (Mabs) against artificial immunogens containing O-phosphotyrosine (pTyr) or tripeptide pTyr-Gly-Gly as haptens were generated; the haptens were coupled to carrier proteins (bovine serum albumin, human immunoglobulin, keyhole limpet hemocyanin). After immunization of mice with pTyr coupled to keyhole limpet hemocyanin, Mabs were generated which were highly specific for pTyr and did not cross-react with O-phosphoserine, O-phosphothreonine, tyrosine or nucleoside-5'-monophosphates. The Mabs specifically react with tyrosinephosphorylated proteins in the Rous sarcoma virus-transformed rat XC-cell. 相似文献
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O A Osipovich A B Sudarikov T S Kolesnikova N I Misuno N N Vo?tenok 《Biulleten' eksperimental'no? biologii i meditsiny》1992,113(6):638-640
The p53 gene has been associated with malignant transformation as well as "anti-oncogene" activity. In the present report expression of p53 in resting and activated human blood monocytes and lymphocytes is analyzed. It is found that human monocytes freshly isolated by continuous percoll gradient centrifugation contained detectable level of p53 mRNA. Stimulation of monocytes by potent activation inducer Staphylococcus Aureus Cowan I for 3-5 hr caused disappearance of r53 mRNA. In contrast, induction of high level of TNF-alpha mRNA was detected. Addition of cycloheximide had no effect on p53 mRNA content in stimulated monocytes, and caused disappearance of mRNA in resting cells. In lymphocytes cultures p53 mRNA was absent in freshly isolated cells and in resting lymphocytes cultured for 20 hr. Activation of lymphocytes by lectin caused accumulation of p53 mRNA. We suggest that r53 gene regulation and functions might be different in human monocytes and lymphocytes. 相似文献