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91.
Arciola CR Campoccia D Gamberini S Donati ME Pirini V Visai L Speziale P Montanaro L 《Biomaterials》2005,26(33):6530-6535
The opportunistic pathogen Staphylococcus epidermidis is able to produce biofilm and to frequently cause implant infections. In recent years, it has also exhibited an increasing antimicrobial drug resistance. Here, the resistance to a panel of 16 different antibiotics in 342 clinical strains of S. epidermidis from orthopaedic implant infections has been investigated. The isolates were pheno- and genotyped for extracellular polysaccharide production, relevant to staphylococcal biofilm formation, in order to ascertain possible associations with antibiotic resistance. Approximately 10% of the isolates were found to be sensitive to all screened antibiotics. In all, 37-38% were resistant to beta-lactams such as oxacillin and imipenem, while the resistance to penicillin, ampicillin, cefazolin, cefamandole, was consistently observed in over 80% of the strains. Erythromycin- and clindamycin- resistant strains were approximately 41% and 16%, respectively. Of the isolates, 10% was resistant to chloramphenicol, 23% to sulfamethoxazole and 26% to ciprofloxacin. Resistance to vancomycin was never observed. Interestingly, exopolysaccharide-producing strains exhibited a significantly higher prevalence in the resistance to the four aminoglycosides (gentamicin, amikacin, netilmicin, tobramycin), to sulfamethoxazole and to ciprofloxacin with respect to non-producing isolates. Moreover, multiple resistance to antibiotics was more frequent among exopolysaccharide-forming strains. 相似文献
92.
93.
Genome of the European elk papillomavirus (EEPV) 总被引:1,自引:0,他引:1
The genome of the European elk papillomavirus (EEPV) was found to be 8,095 base pairs (bp) long and its genetic organization was similar to that of other papillomaviruses. Ten open reading frames (ORFs), designated E1-E7 and L1-L3, were identified in the genome, all located on one strand. The presence of the L3 ORF is rare among the papillomaviruses and to date has only been identified in the genomes of EEPV, the deer papillomavirus (DPV) and the Cottontail papillomavirus (CRPV). The ORF is well conserved beteeen DPV and EEPV with regard to both length and sequence. Potential promoter regions were identified at the 5-end of the E6 ORF, at the 3-end of the E1 ORF and downstream of the L1 ORF. Furthermore, two potential polyadenylation signals were found, one located in the long control region (LCR), downstream of the L1 ORF, and another preceding the L2 ORF. The EEVP genome is closely related to the genome of the DPV, the most highly conserved regions being ORFs E1 (70%), E5 (69%), and L1 (74%). 相似文献
94.
Jorge A. Negroni Elena C. Lascano Ricardo H. Pichel 《Annals of biomedical engineering》1987,15(1):35-50
We undertook a theoretical analysis of the source resistance of the left ventricle represented in a mean pressure-mean flow
diagram, using the chamber properties established in terms of the pressure-volume relationship. This analysis showed that
pairs of points should lie above the linear function proposed by Elzinga and Westerhof. A third-order polynomial function
would theoretically explain better than a linear relation or a parabolic fit the curved shape of experimentally obtained
relationships. The analysis resolves the discrepancy between Elzinga and Westerhof's theoretical concept of linear source
resistance and the actual nonlinear
relationship. 相似文献
95.
Jorge D. Erusalimsky David Gilmore Cesar Milstein 《European journal of immunology》1987,17(5):623-628
The induction of class I HLA expression by interferon-α (IFN-α) was studied in lymphoid cells arrested or traversing different stages of the cell cycle. Exponential cultures of MOLT-4 cells and the MOLT-4 cell variant YHHH were treated with the cell cycle inhibitors aphidicolin and colcemid to obtain cell populations arrested in G1/S and G2/M, respectively, and also cells traversing from S to M and vice versa. Cytofluorimetry with the monoclonal antibody YTH/76.3 (which specifically detects those class I molecules which are most susceptible to IFN-α induction) was used to quantitate the class I HLA response to IFN-α. The results showed that the response to IFN-α is not restricted to a given stage of the cell cycle. These studies also revealed that when the cells were arrested at G1/S, the absolute level of class I HLA expression was enhanced 2–3-fold, both in the presence or absence of either IFN-α or IFN-γ. Therefore, even when absolute levels changed, the ratio of IFN-induced expression to basal expression remained constant at all cell cycle stages. The level of expression of another surface antigen (the CD1 antigen HTA-1) was not affected by the G1/S block. The results were confirmed by dot blot hybridization of poly (A)+ RNA using cDNA-specific probes. These findings suggest that the effect of IFN-α is continuous throughout the cell cycle but that a G1-dependent event determines the extent of class I HLA expression, and leads to a synergistic superinduction by IFN in G1/S-arrested cells. 相似文献
96.
Imaging by scanning electron microscopy (SEM) can provide insight into viral egress. At a low magnification level, varicella zoster virions (VZV) emerge from an infected cell surface in a distinctive pattern previously described as "viral highways." Viral highways consist of thousands of particles arranged in linear pathways across the syncytial surface. This egress pattern has not been described with other herpesviruses, but a systematic analysis has not been performed. Therefore, the characteristic arrangement of VZV egress was compared with that of six other members of the herpes virus family, including herpes simplex virus (HSV) types 1 and 2, human cytomegalovirus (CMV), pseudorabies virus (PRV), and human herpesvirus types 6 and 7 (HHV-6 and HHV-7). Only VZV-infected cells exhibited viral highways. Subsequent SEM examination of VZ virions at an ultra high-resolution revealed that more than 70% were aberrant. Further imaging of the other herpesviruses demonstrated that VZV structure was more closely related to PRV than HSV-1 or HSV-2. Finally, it is noted that the individual members of the herpesvirus family have distinguishable SEM profiles. 相似文献
97.
Can energy drinks reduce the depressor effect of ethanol? An experimental study in mice 总被引:3,自引:0,他引:3
Ferreira SE Hartmann Quadros IM Trindade AA Takahashi S Koyama RG Souza-Formigoni ML 《Physiology & behavior》2004,82(5):841-847
Although the popularization of the combined use of alcoholic beverages and energy drinks (ED) containing caffeine, taurine and other substances has increased, there are no controlled experimental studies on the effects of ED alone or combined with ethanol. This work aimed at evaluating the effects of different doses of ED combined or not with ethanol, on the locomotor activity of Swiss mice. The administration of 3.57, 10.71 or 17.86 ml/kg of ED alone increased the locomotor activity of the animals in relation to a control group. Low doses of ethanol (0.5, 1.0 and 1.5 g/kg) alone or in combination with 10.71 ml/kg of ED did not affect their locomotor activity. However, the reduction of activity observed after 2.5 g/kg of ethanol was antagonized by 10.71 ml/kg of ED. Further studies on the mechanisms of this interaction are still needed. 相似文献
98.
Human heat shock protein 60 (409-424) fragment is recognized by serum antibodies of patients with acute coronary syndromes. 总被引:7,自引:0,他引:7
Jan Wysocki Bozena Karawajczyk Jacek Górski Artur Korzeniowski Zbigniew Ma?kiewicz Gotfryd Kupryszewski Renata Glo?nicka 《Cardiovascular pathology》2002,11(4):238-243
Acute coronary syndromes (ACS), including unstable angina (UA) and acute myocardial infarction (MI), are clinical manifestations of a progressive atherosclerotic process. Antibodies (Ab) to heat shock proteins (hsp) have been reported to be associated with atherosclerosis. Blood samples from 35 patients with ACS and 20 healthy volunteers were tested for Ab to human hsp60 by an enzyme-linked immunosorbent assay (ELISA). Levels of specific serum Ab against hsp60 were significantly elevated in patients with ACS when compared to clinically healthy subjects. To determine the antigenic determinants recognized by these Ab, antibody binding to seven peptides, selected from the hydrophilic and acrophilic regions of the human hsp60 molecule, was assessed. Despite the individual variation in the immune response among patients, one immunodominant region was revealed corresponding to the hsp60 (409-424) peptide. The identification of this epitope may be important for understanding the function of this protein in the atherosclerotic process. 相似文献
99.
100.
Dr. Zdravko Jelesić Dr. Renata Kikinis-Jelesić Dr. Gojko Jelesić 《Archives of virology》1955,6(4):374-378
Zusammenfassung
Die artifizielle Hibernation hemmt und verzögert die Vermehrung und die Ausbreitung von Virus Aujeszky im ZNS. peripher infizierter Kaninchen erheblich.
Hierdurch findet die frühere Beobachtung 1, wonach die Dauer der Inkubationsperiode und des Krankheitsverlaufes des M. Aujeszky bei Kaninchen beträchtlich verlängert ist, eine hinreichende Erklärung. 相似文献