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991.
BACKGROUND: Diarrheagenic Escherichia coli may cause serious extraintestinal complications, but there is no specific treatment. METHODS: Patients with diarrhea caused by diarrheagenic E. coli, specifically Shiga toxin-producing E. coli and E. coli-expressing intimin and enterohemorrhagic E. coli-hemolysin were treated by administration of pooled bovine colostrum, rich in antibodies to Shiga toxin and enterohemorrhagic E. coli-hemolysin, in a placebo-controlled, double-blind study. Symptom resolution and fecal excretion of infecting strains were assessed. RESULTS: No side effects were attributable to colostrum. Stool frequencies in the group treated with bovine colostrum were significantly reduced compared with those in the placebo group. No effect of therapy on the carriage of the pathogens or on complications of the infection could be demonstrated. CONCLUSIONS: Bovine colostrum is well tolerated and diminishes frequency of loose stools in children with E. coli-associated diarrhea. A prospective study should be conducted among a larger number of children with Shiga toxin-producing E. coli identified early in illness, to determine the effectiveness of colostrum therapy.  相似文献   
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BACKGROUND: The profile of blood donors changed dramatically in Brazil over the past 20 years, from remunerated to nonremunerated and then from replacement to community donors. Donor demographic data from three major blood centers establish current donation profiles in Brazil, serving as baseline for future analyses and tracking longitudinal changes in donor characteristics. STUDY DESIGN AND METHODS: Data were extracted from the blood center, compiled in a data warehouse, and analyzed. Population data were obtained from the Brazilian census. RESULTS: During 2007 to 2008, there were 615,379 blood donations from 410,423 donors. A total of 426,142 (69.2%) were from repeat (Rpt) donors and 189,237 (30.8%) were from first‐time (FT) donors. Twenty percent of FT donors returned to donate in the period. FT donors were more likely to be younger, and Rpt donors were more likely to be community donors. All were predominantly male. Replacement donors still represent 50% of FT and 30% of Rpt donors. The mean percentage of the potentially general population who were donors was approximately 1.2% for the three centers (0.7, 1.5, and 3.1%). Adjusting for the catchment's area, the first two were 2.1 and 1.6%. CONCLUSIONS: Donors in the three Brazilian centers tended to be younger with a higher proportion of males than in the general population. Donation rates were lower than desirable. There were substantial differences in sex, age, and community/replacement status by center. Studies on the safety, donation frequencies, and motivations of donors are in progress to orient efforts to enhance the availability of blood.  相似文献   
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The heart rate turbulence (HRT) parameters were introduced for risk stratification of ventricular arrhythmias in postmyocardial infarction patients. However, the relationship of these parameters with other risk stratificators such as heart rate variability (HRV), repolarization parameters or left ventricular function is unknown. Furthermore, the influence of age and medication on HRT remains to be evaluated. Holter ECG's of 509 post‐MI patients (1–10 years after MI) were screened for single ventricular extrasystole. In 196 patients the parameters' turbulence onset (TO) and turbulence slope (TS) could be computed. A pathological TO (>0%) and TS (<2.5 ms) was found in 58 and 54 patients, respectively. HRT was not related to gender, but was correlated with age (TS: r = 0.209, P < 0.01) . No relationship was observed between QT interval, QTc interval or QT dispersion and HRT parameters. Individuals with a pathological HRT showed decreased HRV values (e.g., PNN50: 2.8 vs. 11.5; P < 0.001 ). Of all MI patients with systolic left ventricular dysfunction (EF < 45%, n = 46) , 18 showed a pathological TO (39%) compared to 34 out of 142 patients (24%) with an EF > 45%. In contrast, the percentage of pathological HRT was not different between patients with left ventricular hypertrophy (16 out of 59, 27%) compared to patients without LVH (38 out of 133, 28%). The HRT was pathological in 14 out of 24 patients with diabetes mellitus (58%) compared to 40 out of 172 (23%) normoglycemic patients (TO: ?0.6 ± 3.1 vs. ?2.5 ± 5.5, P < 0.02 ). HRT was similar in patients with ß‐blockers (n = 96) as in patients without ß‐blockers (n = 100) . In stable post‐MI patients, HRT is influenced by age and left ventricular function and correlates with heart rate variability. Therapy with ß‐blockers has no influence on HRT, while diabetic patients may have an increased likelihood of pathological HRT.  相似文献   
999.
The mechanisms underlying the genesis and maintenance of T cell memory remain unclear. In this study, we examined the evolution of a complex, antigen-specific T cell population during the transition from primary effector to memory T cells after Listeria monocytogenes infection. T cell populations specific for listeriolysin O (LLO)91–99, the immunodominant epitope recognized by H2-Kd–restricted T lymphocytes, were directly identified in immune spleens using tetrameric H2-Kd–epitope complexes. The T cell receptor (TCR) Vβ repertoire of specific T cells was determined by direct, ex vivo staining with a panel of mAbs. We demonstrate that LLO91–99-specific, primary effector T cell populations have a diverse TCR Vβ repertoire. Analyses of memory T cell populations demonstrated similar TCR diversity. Furthermore, experiments with individual mice demonstrated that primary effector and memory T cells have indistinguishable TCR repertoires. Remarkably, after reinfection with L. monocytogenes, LLO91–99-specific T cells have a narrower TCR repertoire than do primary effector or memory T cells. Thus, our studies show that the TCR repertoire of primary effector T lymphocytes is uniformly transmitted to memory T cells, whereas expansion of memory T cells is selective.  相似文献   
1000.
We have estimated that in 1995 more than £2 million was spent by the National Health Service on throat swabs used to investigate chronic tonsillitis in the UK. This study was devised to assess the value of this investigation. The surface microflora, obtained using a throat swab, was compared with the microflora of the deep tonsil in 30 cases of chronic tonsillitis. None of the throat swabs grew pathogenic organisms, while in 16 cases, heavy growths of recognised pathogens were grown from the tonsillar tissue. This paper demonstrates that throat swabs have little value in the management of chronic tonsillitis, and if the investigation was omitted in this condition, a substantial saving could be made.  相似文献   
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