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51.
Evidence for in vivo incorporation of D-lactate into peptidoglycan precursors of vancomycin-resistant enterococci. 总被引:8,自引:0,他引:8
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M Arthur C Molinas T D Bugg G D Wright C T Walsh P Courvalin 《Antimicrobial agents and chemotherapy》1992,36(4):867-869
The VanA ligase encoded by the vancomycin resistance plasmid pIP816 of Enterococcus faecium BM4147 condenses D-alanine with various D-2-hydroxy and D-2-amino acids in vitro. D-Lactate added to the culture medium restored the vancomycin resistance of a strain that does not produce the VanH dehydrogenase and therefore appears to be a substrate of VanA in vivo. 相似文献
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53.
Current methods of predicting prognosis in transitional cell carcinoma of the bladder fail to provide consistently reliable information about future tumour behaviour. The monoclonal antibody Ki67 recognises an antigen present in actively dividing cells and Ki67 reactivity has been shown to correlate with conventional prognostic indicators in several tumours. In this study, Ki67 antibody was used to determine the proportions of cells undergoing active division in 26 transitional cell carcinomas of the bladder. The proportion of cells stained in muscle invasive tumours (12.3 +/- 5.4%) was significantly greater than in superficial tumours (4.3 +/- 1.9%) and poorly differentiated tumours showed significantly greater proportions of cells staining compared with well or moderately well differentiated tumours. These results show that Ki67 reactivity correlates with high tumour stage and poor differentiation. Ki67 staining provides an easy method of determining tumour cell turnover that might provide additional prognostic information. 相似文献
54.
M J Harrison P A Tomlinson C S Ubhi J Wright J D Hardcastle 《Annals of the Royal College of Surgeons of England》1988,70(2):61-63
Changes in anal pressure have been monitored during the induction of anaesthesia. Falls in pressure accompany loss of consciousness following bolus doses of commonly used intravenous and inhalational anaesthetic agents. Subsequent rises in pressure towards pre-anaesthetic levels are usually associated with the time taken to correct responses and initial recovery. Premedication, including anticholinergic drugs in conventional dosage, does not affect anal pressure. 相似文献
55.
Assault-injured Adolescents Presenting to the Emergency Department: Causes and Circumstances 总被引:1,自引:0,他引:1
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58.
E Meyers G S Bisacchi L Dean W C Liu B Minassian D S Slusarchyk R B Sykes S K Tanaka W Trejo 《The Journal of antibiotics》1987,40(11):1515-1519
Xylocandin is a complex of novel peptides with potent antifungal activity that is produced by Pseudomonas cepacia ATCC 39277. The complex was isolated from the fermentation broth by extraction with butanol-methanol, 9:1, followed by collection of the precipitate formed upon concentration of the solvent extract. Purification was effected by chromatography on reversed phase and size exclusion gels followed by TLC on silica gel. These techniques afforded eight components: A1, A2, B1, B2, C1, C2, D1 and D2. A mixture of the two closely related components, xylocandins A1 and A2, displayed potent anticandidal and antidermatophytic activities in vitro. The activity was diminished by the presence of serum or vaginal washings. No antibacterial activity was demonstrable. 相似文献
59.
M J Wallace K Ogawa K Wright C H Carrasco W Richli C Charnsangavej 《AJR. American journal of roentgenology》1986,147(6):1247-1250
New inferior vena caval filters for percutaneous placement were made by attaching filter wires similar to those in the bird's nest inferior vena caval filter onto expandable metallic stents. These stents formed a base on which to anchor the filter to the wall of the inferior vena cava. The stent filter can be introduced through a 12- to 13-French catheter sheath system. The system was successfully tested in 13 dogs. 相似文献
60.
W C Hanigan J Gibson N J Kleopoulos T Cusack G Zwicky R M Wright 《Journal of neurosurgery》1986,64(4):575-580
Five cases of fetal ventriculomegaly are described in detail. Following ultrasonography, either computerized tomography or magnetic resonance imaging was used in an attempt to clarify the structural pathology of the ventriculomegaly. In two patients, a precise diagnosis was achieved while a probable diagnosis was established in a third patient. The diverse etiology of fetal ventriculomegaly in these five cases demonstrates that ancillary medical imaging may be necessary to achieve diagnostic precision prior to therapeutic intervention. 相似文献