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21.
IntroductionIn order to deliver high quality results, detection and elimination of possible analytical interferences, such as lipaemia, is crucial. The aim of this study is to evaluate the efficacy of high-speed centrifugation in eliminating lipaemic interference and to define own lipaemic index (LI) for the studied biochemical analytes.Materials and methodsEvaluated analytes were: albumin, alkaline phosphatase, alanine-aminotransferase (ALT), aspartate-aminotransferase (AST), calcium, creatinine, gamma-glutamyltransferase (GGT), glucose, phosphates, total proteins, urea and total bilirubin. Those analytes and LIs have been analysed in duplicate in the Roche Diagnostics-c8000 analyser in samples centrifuged at 3000 rpm/10 minutes in the SL16 (Thermo Scientific, Waltham, USA) centrifuge and according to an own high-speed centrifugation protocol (12,900 rpm/15 minutes) in the MicroCL17R (Thermo Scientific, Waltham, USA) centrifuge. Lipaemia has been measured in each sample. The efficiency of high-speed centrifugation is verified by the Wilcoxon test (P < 0.05). In cases where significant differences are observed, our own LI is calculated. For ALT and AST, it is verified by McNemar test (P < 0.05). For creatinine, both Wilcoxon and McNemar test were applied.ResultsThere were statistically significant differences in analyte concentration before and after high-speed centrifugation for: albumin, creatinine, GGT, glucose, phosphates, urea and total bilirrubin. Own LI is calculated. McNemar test shows statistically significant diferences in the proportion of delivered results before and after high-speed centrifugation in ALT, AST and creatinine.ConclusionsThis study confirms the efficacy of high-speed centrifugation protocol for all the considered analytes, excepting calcium, alkaline phosphatase and total proteins.  相似文献   
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Resumen

Se ha estudiado durante 6 meses el desarrollo de 4 sujetos, que tenían 7, 12, 18 y 21 meses de edad al comienzo de la investigación. Para ello se ha grabado en video a los sujetos mensualmente, durante una hora, en su hogar. También se le han aplicado pruebas de las escalas de desarrollo de Uzgiris y Hunt (1975) para determinar su desarrollo cognitivo.

Sobre los 9 meses los niños ya son capaces de comunicar algunas intenciones, mediante gestos y vocalizaciones. Las funciones que cubren son progresivamente sustituidas y ampliadas por producciones que ya son lingüísticas. La eclosión del lenguaje se manifiesta después de que los niños realizan avances importantes en su desarrollo cognitivo, en el establecimiento de relaciones entre producciones fonéticas y significados intencionales, y en sus conductas comunicativas. Se concluye que, si bien la aparición del lenguaje es preparada por estas formas transicionales y logros anteriores, ninguna de ellas aisladamente permite explicar el empleo sistemático de palabras, que supone un nivel cualitativamente nuevo en la competencia de los niños, resultado de una síntesis creadora de logros precedentes.  相似文献   
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Consumer distrust is only recently beginning to be perceived as an important e-commerce issue and, unlike online trust, the nature and role of distrust is much less established. This study examines the influence of two important consumer characteristics (ethical ideology and risk aversion) on consumer’s ethically-based distrust of online retailers. Also, the moderating role of consumer’s need for personal contact with sales staff is tested. Results from 409 online consumers confirm that both relativist-based ethical ideology and risk aversion are strongly and positively related to consumers’ distrust. Interestingly, our findings show that positive effects of relativism and risk aversion on consumer’s distrust are moderated by consumers’ need for personal interaction, which is more pronounced for those consumers with a high need for personal interaction with retail salespeople.  相似文献   
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Describes the process behind – and the progress of – a unique project designed to explore many of the technical and economic issues pertaining to the implementation and use of an electronic library.  相似文献   
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Artificial rugby union playing surface installation is increasing. This prospective cohort study aimed to examine the effect of playing surface on match injury types within 157 players of two UK professional rugby union clubs playing 209 matches (96 on artificial surfaces and 113 on grass) over three seasons. There was no difference in overall injury risk between the two playing surfaces with injury incidence on artificial 80.2 (CI 69.9–91.7) and on grass 81.9 per 1000 match-hours (CI 72.2–92.5), with an incidence rate ratio (RR) of 0.98 (CI 0.82–1.17). There was a higher rate of concussion (RR 0.52, CI 0.34 – 0.78) and chest injuries on grass (RR 0.26 CI 0.07, 0.95), and a higher rate of thigh haematoma (RR 2.25, CI 1.05–4.82) foot injuries (RR 4.12, CI 1.10, 15.40) and injury to players being tackled (RR 1.46, CI 1.00, 2.15) on artificial. Whilst there was no higher injury risk for matches played on artificial versus natural grass surfaces, the higher incidence of concussion and chest injury on grass, and the higher rate of foot injuries on artificial surfaces may be related to tackle and footwear-to-surface interface factors.  相似文献   
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This essay provides an overview of the huelga schools established in Houston, Texas, in 1970. For 2 years, from 1970 to 1972, the Mexican American community opposed the Houston Independent School District’s plan to integrate the schools by pairing so-called White Mexican Americans with African American students. While they protested this decision, Mexican Americans also established huelga or strike schools in order to provide their children with basic skills in education and to explain the meaning and significance of their political actions. This is the history of the huelga schools established in the 1st months of this struggle.  相似文献   
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The success of students with disabilities in school and community largely relies on productive family professional partnerships (FPPs). The Individuals with Disabilities Education Act (IDEA, 2004) recognises the importance of family collaboration to student success by mandating that parents be involved in the Individualised Education Plan (IEP) process as full team members. While several previous studies examined the perspectives of parents of children with disabilities on partnerships with educators, less research exists on teacher perspectives on family professional collaborations. Additionally, there are even fewer studies that focus on teacher perspectives on partnerships with parents of children with autism, a disability category which continues to increase in prevalence. The present study contributes to the literature by examining teacher perspectives on factors that build and hinder positive partnerships with families of children with autism. Researchers surveyed 25 Special Education teachers and conducted additional individual interviews and open-ended questionnaires to examine teachers' first-hand experiences. Findings identified four common themes that educators felt helped and hindered collaborative relationships with families. Study results may lead to the development of specific family professional collaboration strategies that can be implemented and discussed in school districts, teacher trainings, pre-service teacher education programs and family workshops.  相似文献   
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Resumen

Dos grupos extremos en cuanto a rendimiento escolar son comparados respecto a 21 variables reunidas en un cuestionario. Cada grupo está formado por 36 estudiantes varones de 7.° y 8.° de EGB de un colegio estatal de Madrid con una población de 1.360 estudiantes. Los sujetos de un grupo obtuvieron en el año anterior tres o más sobresalientes y los del otro grupo tres o más suspensos cada uno. Las variables fueron seleccionadas en sesiones de discusión sobre el fracaso escolar por los profesores del centro y cubren distintos aspectos de la ocupación del tiempo libre, realización de las tareas escolares, dificultades con los estudios, valoración de los mismos, nivel cultural de los padres, relaciones familiares y relaciones en el colegio.

Las variables que mayor interés presentan, tanto por su gran efecto discriminativo como por la plausibilidad de una explicación causal, son, en primer lugar, las dificultades de atención-concentración, seguidas por el nivel educativo de los padres, sin que las relaciones de esta última con otras variables ayuden a entender el modo cómo influye en el éxito/fracaso escolar.

Como principales variables concomitantes, interactuando con el éxito/fracaso, aparecen: una mayor dedicación a actividades extraacadémicas, mayor afición por la lectura y una mayor valoración de la importancia del estudio para la vida futura entre los estudiantes sobresalientes.

Sorprendentemente, ambos grupos no muestran diferencias en diez variables, entre las que destacan el número de horas dedicadas al estudio, la satisfacción con los profesores y las relaciones familiares.  相似文献   
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