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The WHO recommends exclusive breastfeeding for 6 months, but despite interventions, breastfeeding rates remain stubbornly low. Financial voucher incentives have shown promise but require a biomarker for validation of intake. This study aimed to develop a simple biochemical assay of infant urine that would tell if an infant was receiving any breast milk to validate maternal report. Urine samples were collected and snap frozen from 34 infants attending with minor illness or feeding problems, of whom 12 infants were exclusively breastfed, nine exclusively formula fed, and 11 mixed breast/formula fed. High‐performance anion exchange chromatography was used to identify discriminating patterns of monosaccharide composition of unconjugated glycans in a sequence of three experiments. The absolute concentration of all human milk oligosaccharides measured blind could detect “any breastfeeding” only with a sensitivity of 48% and specificity of 78%. Unblinded examination of N‐acetylglucosamine (GlcNAc) measured as GlcNH2 after hydrolysis of GlcNAc improved sensitivity to 75% at the expense of a specificity of 28%. Estimation of the relative abundance of GlcNH2 (GlcNH2[%]) or the ratio of GlcNH2 to endogenous mannose (Man) improved accuracy. In a further blind experiment, the GlcNH2/Man ratio with a cut‐off of 1.5 correctly identified all those receiving “any breast milk,” while excluding exclusively formula fed infants. The GlcNH2/Man ratio in infant urine is a promising test to provide biochemical confirmation of any breastfeeding for trials of breastfeeding promotion.  相似文献   
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Erythema induratum of Bazin (EIB) is a form of tuberculid resulting from hypersensitivity to tuberculosis antigen. EIB occurs most commonly in middle‐aged women and is not typically seen in children. Here, we present a rare case of EIB, presenting as a chronic nodular panniculitis, in a 10‐year‐old Korean boy.  相似文献   
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International Urology and Nephrology - We analyzed the long-term efficacy of simultaneous transurethral resection (TUR) and therapeutic hydrodistention in patients with ulcerative interstitial...  相似文献   
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Background: Engaging and inspiring the next generation of physician-scientists at an early stage is recognised as key to ensure the future of medical research. However, little is known about medical student perceptions of research.

Objectives: We attempted to ascertain perceptions of research and research-orientated careers from medical students studying in different countries.

Methods: An online questionnaire was developed, piloted, and promoted to medical students in various countries.

Results: 1625 responses were collected from 38 countries. Analysis was restricted to data collected from countries with >100 responses (n?=?890). Less than half the respondents felt their medical school provided adequate research training. Key perceived barriers to research participation as a student included lack of time and difficulty finding mentors or projects. A significant gender disparity existed in research ambitions of students with females desiring less research involvement. The importance of barriers and satisfaction with research training differed significantly between countries.

Conclusions: Students perceive a number of key barriers to research involvement and pursuit of research-orientated careers. Programmes designed to engage students with research should focus on overcoming identified barriers. Greater effort is needed to engage female students who report more significant barriers and less desire to follow research-orientated careers.  相似文献   
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