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Pathogens in the gastrointestinal tract exist within a vast population of microbes. We examined associations between pathogens and composition of gut microbiota as they relate to Shigella spp./enteroinvasive Escherichia coli infection. We analyzed 3,035 stool specimens (1,735 nondiarrheal and 1,300 moderate-to-severe diarrheal) from the Global Enteric Multicenter Study for 9 enteropathogens. Diarrheal specimens had a higher number of enteropathogens (diarrheal mean 1.4, nondiarrheal mean 0.95; p<0.0001). Rotavirus showed a negative association with Shigella spp. in cases of diarrhea (odds ratio 0.31, 95% CI 0.17–0.55) and had a large combined effect on moderate-to-severe diarrhea (odds ratio 29, 95% CI 3.8–220). In 4 Lactobacillus taxa identified by 16S rRNA gene sequencing, the association between pathogen and disease was decreased, which is consistent with the possibility that Lactobacillus spp. are protective against Shigella spp.–induced diarrhea. Bacterial diversity of gut microbiota was associated with diarrhea status, not high levels of the Shigella spp. ipaH gene.  相似文献   
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BACKGROUND: Procalcitonin (PCT) is a recently described inflammatory marker that has been shown to increase significantly in patients with severe systemic bacterial infections or sepsis. Reports on the diagnostic and predictive value of PCT in systemic fungal infections are limited. METHODS: In order to evaluate the role of PCT in systemic mycosis, 14 patients (mean age 40 years) with proven or probable systemic fungal infections were investigated. Blood samples were collected on days 1, 3, 5, and 10 after the onset of signs and symptoms of systemic fungal infection (clinical and/or laboratory diagnosis and/or radiographic evidence). PCT measurements were performed using an immunoluminometric assay. RESULTS: In five patients with severe fungal infection and an unfavorable course (patient group 2), PCT levels were moderately elevated on day 3 (0.5-1.0 ng/ml), whereas they were normal in the patients who recovered (patient group 1). High PCT levels (>/=1.11 ng/ml) were detected on the 10th day of the course of the illness in patient group 2. A normal or moderate elevation of PCT on day 10 was observed in patient group 1. The difference in mean PCT levels in patient groups 1 and 2 on days 3 and 10 were statistically significant. CONCLUSIONS: PCT levels seem to correlate with the severity and outcome of systemic fungal infection. If this finding can be confirmed in a larger number of patients, it could serve as a prognostic indicator.  相似文献   
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In this experiment, young and elderly adults listened to and recalled sentences that were varied in speech rate through computer-controlled time compression. Half of the sentences at each speech rate were presented with a normal prosodic pattern that reinforced the lexically defined syntactic structure of the sentences, and half were presented with a prosodic contour that conflicted with that structure. Both young and elderly subjects showed better recall for slower speech rates and when prosody was consistent with syntactic structure, but these effects were larger for elderly subjects. When syntax and prosody were placed in conflict, elderly subjects were more likely than the young to reconstruct the lexical content of the presented sentences to produce responses with a syntactic structure consistent with the prosody marking. Although elderly adults may be disadvantaged by rapid speech input rates, we show that they rely on normal prosody to aid syntactic parsing as a step toward language comprehension.  相似文献   
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The relative importance of astrovirus and adenoviruses as etiologic agents of diarrhea among children in day care was examined. Stool specimens from this prospective study were screened for both astrovirus and adenovirus hexon with two new indirect double-antibody assays and for enteric adenoviruses with an EIA specific for serotypes 40 and 41. Astrovirus was detected in a significantly greater percentage of children with diarrhea (4%, 21/524) than of those without (less than 1%, 1/138) (P less than .05); however, no difference between such such children with adenovirus infections was found (8%, 43/565, and 8%, 10/129, respectively). Overall, 30% (13/43) of all adenovirus hexon-positive specimens were enteric serotypes, and by extrapolation, enteric adenoviruses were identified in an equal percentage of children (2%) with and without diarrhea. This study documents the presence of astrovirus and enteric adenoviruses among children in day care in the United States, associates astrovirus with diarrhea in this setting, and suggests that viral agents may be the most common enteric pathogens among children with diarrhea in day care.  相似文献   
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