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本文应用结肠非低张双重对比灌肠造影诊断结肠病变,这是一种简单的方法。本文根据150例的实践径验介绍了技术、病人的准备、有关造影剂的问题和正常所见,并通过具体的病例阐述了结肠非低张双重对比检查的临床应用价值,并指出了本法的不足之处。 相似文献
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Laboratory diagnosis of catheter-related bacteremia. 总被引:2,自引:0,他引:2
Semiquantitative culture of the external surface of catheter tips has become the currently most used method to detect catheter colonisation and catheter-related bacteremia; however, this method may fail to detect significant colonisation of the internal lumen of catheters, and several quantitative methods have been described for this purpose. Although 15 and 1000 CFU are used to define positive catheters, the sensitivity and specificity are not yet well known, and the definitive cut-off level for a positive result remains to be established. We studied prospectively 91 intravascular catheter tips removed because a catheter-related infection was suspected. The result of external and internal cultures with different cut-off levels, alone or combined, were correlated with clinical data in 22 bacteremic episodes which occurred in these patients, 12 of which were catheter-related. The semiquantitative culture of the external surface alone with a cut-off level of 25 CFU provided the best means of detecting catheter-related bacteremia. This method has 100% sensitivity and 81.1% specificity. We conclude that semiquantitative culture technique of the catheter tip alone is sufficient and this method should be employed for diagnosing catheter-related bacteremia in unselected populations. 相似文献
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F. Deulofeu J. M. Nava F. Bella C. Martí M. A. Morera B. Font D. Fontanals J. Lite J. Garau A. Calderón M. T. Coll S. Uriz V. Pineda 《European journal of clinical microbiology & infectious diseases》1994,13(8):633-638
The incidence and characteristics of invasiveHaemophilus influenzae disease were studied in 43 adult patients admitted to the acute care hospitals in El Vallés County (Barcelona, Spain) between January 1987 and June 1992. The annual incidence ofHaemophilus influenzae disease was 1.2 per 100,000 inhabitants. Pneumonia occurred in 24 patients, meningitis in five, intraabdominal infections in three, obstetric infections in two, epiglottitis in two and cellulitis in one. In six patients the source of infection was unknown. Ten (23 %) of the infections were hospital acquired. Underlying conditions were diagnosed in 30 (70 %) patients. NontypeableHaemophilus influenzae strains predominated in all adult age groups. Sixty-one percent of type b and 34 % of nontypeable strains were ampicillin resistant (p=0.08). Multiple antibiotic resistance was also high among type b (53 %) and nontypeable (18 %) strains. The mortality rate was significantly higher in patients with pneumonia, bactaeremia from an unidentified focus or shock at presentation. 相似文献
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The widely adopted value of (102+/-5)a for the (209)Po half-life, which is based on a single determination reported in 1956, appears to be in error by a large factor. Decay data from two separate primary standardizations of a (209)Po solution standard, conducted approximately 12 years apart, are inconsistent with the adopted value and its assigned uncertainty. An estimated half-life, larger than the adopted value by about 25%, is more consistent with the standardization data. A longer half-life is also supported by measurements on a recently standardized (210)Pb solution standard. 相似文献
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Isolation of Fc-binding molecules was performed by complexing IgG antibodies and the corresponding antigens in lysates of radiolabeled rabbit lymphoid cells. A single-chain molecule of 110 000 apparent mol. wt. (unreduced) or 120 000 (reduced) was observed in sodium dodecyl sulfate polyacrylamide gel electrophoresis when the antibodies were in the IgG form but not as F(ab')2. This molecule was very susceptible to proteolysis, but the fragments thus produced remained associated by disulfide bridges, and the binding properties of the molecule were conserved. The molecule and its proteolytic fragments (mol. wts. 75 000, 45 000 and 20 000) were very similar to those obtained for the mouse Fc receptor under similar conditions, and therefore the molecule was designated as rabbit Fc receptor. Among several precipitating systems used, some Ig-anti-Ig complexes appeared to be the most efficient in coprecipitating the rabbit Fc receptor. Remarkably high titers of Fc receptor were found on lymphocyte membrane of infected rabbits, in agreement with a possible role of this molecule in immune regulation. 相似文献
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Prats G Navarro F Mirelis B Dalmau D Margall N Coll P Stell A Johnson JR 《Journal of clinical microbiology》2000,38(1):201-209
To clarify the clinical and bacteriological correlates of urinary-tract infection (UTI) due to Escherichia coli O15:K52:H1, during a 1-year surveillance period we prospectively screened all 1, 871 significant E. coli urine isolates at the Hospital de la Santa Creu i Sant Pau, Barcelona, Spain, for this serotype and assessed the epidemiological features of community-acquired UTI due to E. coli O15:K52:H1 versus other E. coli serotypes. We also compared the 25 O15:K52:H1 UTI isolates from the present study with 22 O15:K52:H1 isolates from other, diverse geographic locales and with 23 standard control strains (8 strains from the ECOR reference collection and 15 strains of nonpathogenic O:K:H serotypes) with respect to multiple phenotypic and genotypic traits. Although E. coli O15:K52:H1 caused only 1.4% of community-acquired E. coli UTIs during the surveillance period, these UTIs were more likely to present as pyelonephritis and to occur in younger hosts, with similar risk factors, than were UTIs due to other E. coli serotypes. Irrespective of geographic origin, E. coli O15:K52:H1 strains exhibited a comparatively restricted repertoire of distinctive virulence factor profiles (typically, they were positive for papG allele II, papA allele F16, and aer and negative for sfa, afa, hly, and cnf1), biotypes, ribotypes, and amplotypes, consistent with a common clonal origin. In contrast, their antimicrobial resistance profiles were more extensive and more diverse than those of control strains. These findings indicate that E. coli O15:K52:H1 constitutes a broadly distributed and clinically significant uropathogenic clone with fluid antimicrobial resistance capabilities. 相似文献