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CJ Stewart ECL Marrs S Magorrian A Nelson C Lanyon JD Perry ND Embleton SP Cummings JE Berrington 《Acta paediatrica (Oslo, Norway : 1992)》2012,101(11):1121-1127
Aim: To describe gut colonization in preterm infants using standard culture and 16S gene rRNA profiling, exploring differences in healthy infants and those who developed NEC/late onset sepsis (LOS). Methods: Ninety‐nine stools from 38 infants of median 27‐week gestation were cultured; 44 stools from 27 infants had their microbial profiles determined by 16S. Ordination analyses explored effects of patient variables on gut communities. Results: Standard microbiological culture identified a mean of two organisms (range 0–7), DGGE 12 (range 3–18) per patient. Enterococcus faecalis and coagulase negative staphylococci (CONS) were most common by culture (40% and 39% of specimens). Meconium was not sterile. No fungi were cultured. Bacterial community structures in infants with NEC and LOS differed from healthy infants. Infants who developed NEC carried more CONS (45% vs 30%) and less Enterococcus faecalis (31% vs 57%). 16S identified Enterobacter and Staphylococcus presence associated with NEC/LOS, respectively. Conclusions: Important differences were found in the gut microbiota of preterm infants who develop NEC/LOS. The relationship of these changes to current practices in neonatal intensive care requires further exploration. 相似文献
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The ‘new sociology of childhood’ has activated a growing interest in children as social actors and their level of involvement in activities that affect their lives. In the field of research, debate is underway regarding the consent processes and methodological activities that support child participation. This paper highlights methodological and ethical considerations that emerged while engaging in research with young boys (aged 9–11 years old) with a formal diagnosis of attention-deficit/hyperactivity disorder (ADHD). Key issues include recruitment, informed consent, and participatory activities for data production. Sociocultural theories of childhood and disability are applied to reflect on the power and privilege operating through the research process. Engaging in research that involves children with disabilities, in which discourses of risk, stigma, and protection are elevated, problematizes the researcher–researched relationship and expands considerations of what constitutes ethical practice and ‘valuable data’. 相似文献
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Karla Berdichevsky Christine Tucker Alberto Martínez Suellen Miller 《Health care for women international》2013,34(5):444-457
We conducted a qualitative study to explore responses to a low-technology first-aid device for management of life-threatening obstetric hemorrhage in rural health facilities in Mexico. This entailed in-depth, semistructured interviews with clinical and administrative staff (n = 70) involved in pilot studies of the nonpneumatic antishock garment (NASG) at primary health care facilities and rural hospitals. We found that staffs’ response fell into four categories: owning, doubting, resisting, and rejecting. Overall, there were positive reactions to the garment as a relevant technology for saving women's lives. Findings will be used for future implementation of the garment and other new technologies. 相似文献
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Price GD Woodger FJ Badger MR Howitt SM Tucker L 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(52):18228-18233
Cyanobacteria possess a highly effective CO(2)-concentrating mechanism that elevates CO(2) concentrations around the primary carboxylase, Rubisco (ribulose-1,5-bisphosphate carboxylase/oxygenase). This CO(2)-concentrating mechanism incorporates light-dependent, active uptake systems for CO(2) and HCO(-)(3). Through mutant studies in a coastal marine cyanobacterium, Synechococcus sp. strain PCC7002, we identified bicA as a gene that encodes a class of HCO(-)(3) transporter with relatively low transport affinity, but high flux rate. BicA is widely represented in genomes of oceanic cyanobacteria and belongs to a large family of eukaryotic and prokaryotic transporters presently annotated as sulfate transporters or permeases in many bacteria (SulP family). Further gain-of-function experiments in the freshwater cyanobacterium Synechococcus PCC7942 revealed that bicA expression alone is sufficient to confer a Na(+)-dependent, HCO(3)(-) uptake activity. We identified and characterized three cyanobacterial BicA transporters in this manner, including one from the ecologically important oceanic strain, Synechococcus WH8102. This study presents functional data concerning prokaryotic members of the SulP transporter family and represents a previously uncharacterized transport function for the family. The discovery of BicA has significant implications for understanding the important contribution of oceanic strains of cyanobacteria to global CO(2) sequestration processes. 相似文献
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This paper describes the clinical validation of the 10-question Short Zung Interviewer-assisted Depression Rating Scale (Short Zung I.D.S.) which has been derived from the 20-question Zung Self-rating Depression Scale (Zung S.D.S) for use in the elderly. The Short Zung I.D.S. was administered to 104 elderly volunteers from the community and to 33 elderly depressed patients assessed by a psychiatrist. The mean scores (41.3 and 81.0, respectively) were significantly different (P less than 0.0001). The Short Zung I.D.S. has proved to be a useful brief screening test for depression in the elderly and should be of value in measuring changes in mood. 相似文献