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Recent studies suggest a synergic effect of infection and hypoxia-ischemia in the causation of perinatal brain damage. We conducted a prospective pilot study on the presence of infection in hypoxic-ischemic encephalopathy (HIE), focusing on neurotropic viruses. Sixteen newborns with HIE were included in the study. There were no confirmed cases of viral infection. There was a case of bacterial early onset sepsis and four cases of suspected sepsis due to clinical and/or analytical signs, but with negative cultures. Our results do not support universal screening for viral infection in cases of HIE.  相似文献   
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Purpose

To study the psychometric properties, including reliability, validity and responsiveness, of the Spanish EQ-5D-5L questionnaire for patients with hip or knee osteoarthritis (OA).

Methods

We included 758 patients with hip or knee OA who completed the EQ-5D-5L and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) at baseline, of whom 644 also did 6 months later. The EQ-5D-5L contains five questions from which a utility index is derived. The WOMAC covers three dimensions: pain, stiffness and physical function. Floor and ceiling effects were calculated. Reliability was assessed using Cronbach’s alpha. Convergent validity was tested using the Spearman correlation coefficient between EQ-5D-5L and WOMAC. We examined known-groups validity by comparing the EQ-5D-5L between subgroups defined by WOMAC scores using ANOVA or the Kruskal–Wallis test. Effect sizes were calculated to assess responsiveness, and minimal clinically important difference (MCID) was estimated.

Results

The EQ-5D-5L showed minimal floor and ceiling effects (<?3%). Cronbach’s alpha was 0.86. The EQ-5D-5L index was strongly correlated with WOMAC pain and function scores (??0.688 and ??0.782). Patients with higher WOMAC scores had significantly (p?<?0.0001) lower EQ-5D-5L index. The 20.19% had hip or knee replacement during the follow-up. Effect sizes were small among non-surgical patients, but >?0.80 among “improved” surgical patients, being the MCID for improvement 0.32 points.

Conclusions

The results support the reliability, validity and responsiveness of the EQ-5D-5L, overcoming the limitations of the EQ-5D-3L in these patients. Therefore, the EQ-5D-5L could be very useful as an outcome measure, at least in patients with hip or knee OA.
  相似文献   
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Maximising power output during the initial acceleration phase of a bicycle motocross (BMX) race increases the chance to lead the group for the rest of the race. The purpose of this study was to investigate the effect of non-circular chainrings (Q-ring) on performance during the initial acceleration phase of a BMX race. Sixteen male cyclists (Spanish National BMX team) performed two counterbalanced and randomized initial sprints (3.95s), using Q- ring vs. circular chainring, on a BMX track. The sample was divided into two different groups according to their performance (Elite; n = 8 vs. Cadet; n = 8). Elite group covered a greater distance using Q-ring (+0.26 m, p = 0.02; D = 0.23), whilst the improvement for the Cadet (+0.04 m) was not significant (p = 0.87; D = -0.02). Also, there was no significant difference in power output for the Elite group, while the Cadet group revealed larger peak power with the circular chainring. Neither lactate level, nor heart rate showed significant differences due to the different chainring used. The non-circular chainring improved the initial acceleration capacity only in the Elite riders.

Key Points

  • This work provides novel results demonstrating very significant improvements in the sprint performance of BMX cycling discipline using a non-circular chainring system.
  • This study seeks a practical application from scientific analysis
  • All data are obtained in a real context of high competition using a sample comprised by the National Spanish Team.
  • Some variables influencing performance as subjects’ physical fitness are discussed.
  • Technical equipment approved by International Cycling Union is studied to check its potentially beneficial influence on performance.
Key words: Power, efficiency, pedalling, biomechanics, lactate  相似文献   
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The purpose of this study was to develop a predictive model for perceived competence and to obtain an integrator evaluation of the nursing curriculum with measures of nursing self‐efficacy, general self‐efficacy, resilience, and stress among nursing students. A correlational study with nursing students (N = 265) from the degree in nursing was conducted. A factor analysis was used to test the construct validity of nursing self‐efficacy and perceived competence. The correlational and discriminant analyses evaluated the factors in the four academic levels of the degree (2016–2017) to identify the variables involved in the classification of the students in each level. The results of exploratory and confirmatory factor analyses of nursing self‐efficacy and perceived competence revealed a statistically significant good fit and consistency. Nursing self‐efficacy, general self‐efficacy, resilience, and year of the degree course predicted 34% of perceived competence scores. The discriminant function of nursing self‐efficacy, perceived competence, and resilience classified 76% of participants in the first and last years of the degree. Nursing self‐efficacy, perceived competence, and resilience increased with academic level. They help chart nursing students' progress through the curriculum.  相似文献   
27.
Tatton-Brown-Rahman syndrome (TBRS) is an overgrowth disorder caused by germline heterozygous mutations in the DNA methyltransferase DNMT3A. DNMT3A is a critical regulator of hematopoietic stem cell (HSC) differentiation and somatic DNMT3A mutations are frequent in hematologic malignancies and clonal hematopoiesis. Yet, the impact of constitutive DNMT3A mutation on hematopoiesis in TBRS is undefined. In order to establish how constitutive mutation of DNMT3A impacts blood development in TBRS we gathered clinical data and analyzed blood parameters in 18 individuals with TBRS. We also determined the distribution of major peripheral blood cell lineages by flow cytometric analyses. Our analyses revealed non-anemic macrocytosis, a relative decrease in lymphocytes and increase in neutrophils in TBRS individuals compared to unaffected controls. We were able to recapitulate these hematologic phenotypes in multiple murine models of TBRS and identified rare hematological and non-hematological malignancies associated with constitutive Dnmt3a mutation. We further show that loss of DNMT3A in TBRS is associated with an altered DNA methylation landscape in hematopoietic cells affecting regions critical to stem cell function and tumorigenesis. Overall, our data identify key hematopoietic effects driven by DNMT3A mutation with clinical implications for individuals with TBRS and DNMT3A-associated clonal hematopoiesis or malignancies.  相似文献   
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OBJECTIVE: The objectives of our study were to investigate differences in Doppler sonography features between benign and malignant breast lesions and between malignant lesions with different prognostic factors and to propose diagnostic criteria for Doppler sonography of breast lesions. SUBJECTS AND METHODS: We performed power and duplex Doppler sonography examinations in 826 breast lesions scheduled for sonographically guided core needle biopsy. Lesion vascularity, pulsatility index (PI), and resistive index (RI) of the vessels detected were analyzed and correlated with histologic results. RESULTS: Color flow was more frequently seen in malignant (237/348 lesions, 68%) than in benign (171/478, 36%) lesions (p < 0.001). However, sensitivity, specificity, and positive and negative predictive values for this sign were low (68%, 64%, 58%, and 73%, respectively). The RI and PI values were significantly higher (p < 0.001) in cancers. Although an overlap in these values between benign and malignant lesions was observed, all but one nodule with an RI of greater than 0.99 (those with null or inverted diastolic flow) or a PI of greater than 4 were malignant. No significant relationship was found between PI, RI, or flow visualization on power Doppler sonography and tumor grade or lymph node involvement in cancers. CONCLUSION: Flow visualization on power Doppler sonography indicates a higher possibility of malignancy but is not useful as the main sign for malignancy. However, any lesion with a vessel that has an RI value greater than 0.99 or a PI value greater than 4 within it must be considered as probably malignant regardless of any other sonography sign present. Doppler findings are not useful to predict tumor grade or lymph node involvement.  相似文献   
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