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1.
Two young men with longstanding suprapatellar masses are presented. The initial clinical diagnosis was of a synovial or soft tissue tumour. Magnetic resonance imaging showed the features of an arteriovenous malformation (AVM). Surgical exploration and biopsy confirmed the diagnosis. AVMs, although rare, should be considered as a possible diagnosis of a peri-articular swelling of the knee.  相似文献   
2.
In this paper, we reviewed all existing studies using electroencephalography (EEG) in infants and children with known prenatal exposure to alcohol (PEA). The guiding purposes of the review were to determine if (1) EEG is a useful neuroimaging technique for investigating the brain correlates of PEA in infants and children, (2) there are indeed consistent EEG correlates of PEA in literature, and (3) these EEG correlates can be framed within a coherent picture of emerging implications for the study of PEA and its effects. The review confirms that EEG techniques have proven useful in indicating evidence of differential effects of patterns of PEA and timing in early fetal development and impairment of brain maturation in older children. In general, these techniques could be important in functional assessment of the brain of children affected by PEA, especially if used in conjunction with other neuroimaging techniques. The reviewed studies also suggest that although the impact on sensory and cognitive functions may involve extensive neural networks, there are EEG correlates of PEA which may in the future lead to the identification of neurophysiologic markers. A consistent aspect that emerges from the EEG data is that converging evidence from the study of different systems and processes suggests that PEA may almost invariably have consequences for later neurocognitive development.  相似文献   
3.
Peroxiredoxins are an important class of antioxidant enzymes found from Archaea to humans, which reduce and thereby detoxify peroxides and peroxynitrites. The major thiol-containing surface antigen of the invasive ameba, Entamoeba histolytica, is a peroxiredoxin and is likely to be important during the transition from the anaerobic environment of the large intestine to human tissues. The closely related species, Entamoeba dispar, is incapable of invasion and more sensitive to hydrogen peroxide, yet also has a peroxiredoxin. We cloned and expressed the two active recombinant enzymes and found that their activity was similar by a fluorometric stopped-flow assay, giving a Km of <10 microM for hydrogen peroxide. Three monoclonal antibodies produced to recombinant E. histolytica peroxiredoxin cross-reacted with Entamoeba dispar.E. histolytica contains as much as 50 times more peroxiredoxin than E. dispar as demonstrated by a sensitive capture ELISA. In addition, the peroxiredoxin is present largely on the outer surface of the cell, in contrast to E. dispar. This unusual peroxiredoxin localizes to the site of parasite-host cell contact where it can effectively counteract oxidants generated by host cells, thus facilitating invasion.  相似文献   
4.
Abstract

The ongoing COVID-19 pandemic is unprecedented in the modern age both due to its scale and its disruption to daily life throughout the world. Widespread social isolation and restrictions in the age of modern communicative technology, coupled with some early successes for makers, have united the open-source community towards a common goal in a way not previously seen. Local hospitals and care facilities are turning to makers to print essential consumable parts, such as simple visors, while in the hardest hit areas, critical pieces of medical technology are being fabricated. While important and effective innovations are appearing almost daily, there are also some worrying trends towards hobbyists attempting manufacture of complex medical devices with little understanding of the clinical or scientific rationale behind their design. The nature of the open-source community, an area of intensive innovation, fluidity, and experimentation, jars with the exacting standards of medical device regulation. Here, we review the involvement of rapid prototyping and the open-source community in the key areas of personal protective equipment (PPE), diagnostics, critical care technology, and information acquisition and sharing, highlighting where makers and hackers have clashed with medical device regulations, and areas where the system has worked well to facilitate change.  相似文献   
5.
6.
The accurate identification of the nursing diagnoses and the corresponding measurement of their indicators will depend on the elements in the standardized language systems.

OBJECTIVE

To analyze the correspondence between elements of four NANDA‐I nursing diagnoses and outcomes suggested by the nursing outcomes classification (NOC) for the resolution of these diagnoses.

METHOD

A methodological study consisting of cross‐mapping was performed in the first stage between definitions, defining characteristics (DCs), and related factors (RFs) of impaired oral mucous membrane, impaired tissue integrity, spiritual distress, and delayed surgical recovery and outcome definitions and indicators to measure results of diagnoses resolution and an analysis of its relevance by experts in the second stage.

RESULTS

It found partial correspondence between outcome indicators, DCs, RFs, and definitions.

CONCLUSION

The data evidence the relevance of this review for a reliable application of these taxonomies and demonstrated partial correspondence between concepts analyzed. A identificação precisa dos diagnósticos de enfermagem e a medida correspondente dos seus indicadores dependerá dos elementos nos sistemas de linguagem padronizados.

OBJETIVO

Foi analisar a correspondência entre os elementos de quatro NANDA‐I diagnósticos de enfermagem e os resultados sugeridos pelo NOC para a resolução destes diagnósticos.

MÉTODO

um estudo metodológico que consiste em cross‐mapping foi realizado em uma primeira fase entre as definições, características definidoras e fatores relacionados de Mucosa oral prejudicada, Integridade tissular prejudicada, Sofrimento espiritual e Recuperação cirúrgica retardada e as definições dos resultados indicados para a resolução destes diagnósticos; na segunda fase, foi realizada uma análise desta concordância por especialistas.

RESULTADOS

correspondência parcial entre as definições dos diagnósticos e dos resultados, características definidoras e fatores relacionados.

CONCLUSÃO

Os resultados evidenciam a relevância dessa avaliação para uma aplicação confiável destas taxonomias e demonstrou a correspondência parcial entre os conceitos analisados.  相似文献   
7.

Background

Experimental and clinical studies show that prematurity leads to altered left ventricular (LV) structure and function with preserved resting LV ejection fraction (EF). Large-scale epidemiological data now links prematurity to increased early heart failure risk.

Objectives

Echocardiography imaging was performed at prescribed exercise intensities to determine whether preterm-born adults have impaired LV functional response to physical exercise.

Methods

A total of 101 normotensive young adults born preterm (n = 47; mean gestational age 32.8 ± 3.2 weeks) and term (n = 54) were recruited for detailed cardiovascular phenotyping. Full clinical resting and exercise stress echocardiograms were performed, with apical 4-chamber views collected while exercising at 40%, 60%, and 80% of peak exercise capacity, determined by maximal cardiopulmonary exercise testing.

Results

Preterm-born individuals had greater LV mass (p = 0.015) with lower peak systolic longitudinal strain (p = 0.038) and similar EF to term-born control subjects at rest (p = 0.62). However, by 60% exercise intensity, EF was 6.7% lower in preterm subjects (71.9 ± 8.7% vs 78.6 ± 5.4%; p = 0.004) and further declined to 7.3% below the term-born group at 80% exercise intensity (69.8 ± 6.4% vs 77.1 ± 6.3%; p = 0.004). Submaximal cardiac output reserve was 56% lower in preterm-born subjects versus term-born control subjects at 40% of peak exercise capacity (729 ± 1,162 ml/min/m2 vs. 1,669 ± 937 ml/min/m2; p = 0.021). LV length and resting peak systolic longitudinal strain predicted EF increase from rest to 60% exercise intensity in the preterm group (r = 0.68, p = 0.009 and r = 0.56, p = 0.031, respectively).

Conclusions

Preterm-born young adults had impaired LV response to physiological stress when subjected to physical exercise, which suggested a reduced myocardial functional reserve that might help explain their increased risk of early heart failure. (Young Adult Cardiovascular Health sTudy [YACHT]; NCT02103231)  相似文献   
8.
BACKGROUND: We compared the psychometric properties of the ESPRINT-15, the short form of a new Spanish instrument to measure health-related quality of life in allergic rhinitis (AR) patients, with those of the Mini-Rhinoconjunctivitis Quality of Life Questionnaire (MiniRQLQ). METHODS: The questionnaires were compared in Spanish patients with intermittent allergic rhinitis (IAR) or persistent AR in a prospective, observational study. Floor and ceiling effects, internal consistency (Cronbach's alpha), test-retest reliability (intraclass correlation coefficient; ICC), convergent and known groups validity, and sensitivity to change (standardized response means; SRMs) were compared. RESULTS: In terms of content, while the MiniRQLQ has a dimension covering practical problems and places more emphasis on symptoms, the ESPRINT-15 has two dimensions (Sleep and Psychological impact) which are not included in the MiniRQLQ. In the validation study, 400 patients were included and 59% of the sample had persistent AR. There were no significant floor or ceiling effects on any dimension on either questionnaire. Cronbach's alpha values for the ESPRINT-15 and MiniRQLQ overall scores were 0.92 and 0.90, respectively. In 48 clinically stable patients, ICCs were 0.80 and 0.77, respectively. Both instruments discriminated between patients with IAR and persistent AR. Correlations with symptom scores and generic measures were moderate to strong. SRMs for overall scores and individual dimensions on the two questionnaires in the 197 patients reporting a change in health status ranged from 0.7 to 1.3. CONCLUSIONS: Both questionnaires performed well in psychometric terms. The ESPRINT-15 is particularly recommended for use in Spanish-speaking populations.  相似文献   
9.

Background

Valuations of health states were affected by the wording of the two instruments (EQ-5D-3L and EQ-5D-Y) and by the perspective taken (child or adult).

Objectives

There is a growing demand for value sets for the EQ-5D-Y (EQ-5D instrument for younger populations). Given the similarities between EQ-5D-Y and EQ-5D-3L, we investigated whether valuations of health states were affected by the differences in wording between the two instruments and by the perspective taken in the valuation exercise (child or adult). Study Design: Respondents were randomly assigned to EQ-5D-3L or EQ-5D-Y (instrument) and further into two groups that either valued health states for an adult or for a 10-year-old child (perspective). The valuation tasks were composite time trade-off (C-TTO) and discrete choice experiments (DCE), including comparisons with death (DCE + death). Members of the adult general population in four countries (Germany, Netherlands, Spain, England) participated in computer-assisted personal interviews.

Methods

Two-way multivariate analysis of variance (MANOVA) and post hoc tests were used to compare C-TTO responses and chi-square tests were conducted to compare DCE + death valuations.

Results

A significant interaction effect between instrument and perspective for C-TTO responses was found. Significant differences by perspective (adult and child) occurred only for the EQ-5D-3L. Significant differences in values between instruments (EQ-5D-3L and EQ-5D-Y) occurred only for the adult perspective. Both significant results were confirmed by the DCE + death results. When comparing EQ-5D-3L for adult perspective and EQ-5D-Y for child perspective, values were also significantly different.

Conclusions

The results identified an interaction effect between wording of the instrument and perspective on elicited values, suggesting that current EQ-5D-3L value sets should not be employed to assign values to EQ-5D-Y health states.  相似文献   
10.
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