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61.

Introduction

Glycolysis affects glucose determination in vitro. The placement of sample tubes in ice-water slurry with plasma separation within 30 minutes is recommended, or alternatively the use of a glycolysis inhibitor. The aim of our two-steps study was to evaluate which Terumo tube is best for glucose determination in routine clinical setting.

Materials and methods

In the first study, blood from 100 volunteers was collected into lithium heparin (LH), NaF/Na heparin (FH) and NaF/citrate buffer/Na2EDTA (FC-Mixture) tubes. LH sample was treated as recommended and considered as reference, while FH and FC-Mixture samples were aliquoted, maintained at room temperature (RT) for 1, 2 and 4 hours; centrifuged and plasma analysed in triplicate. In the second study, samples from 375 volunteers were collected in LH, FH and FC-Mixture tubes and held at RT before centrifugation from 10 to 340 minutes, depending on each laboratory practice. Samples were analysed in one analytical run.

Results

In the first study, FH glucose concentrations were 5.15 ± 0.66 mmol/L, 5.05 ± 0.65 mmol/L and 5.00 ± 0.65 mmol/L (P < 0.001) in tubes stored at RT for 1, 2 and 4 hours, respectively. Mean biases in all time points exceeded the analytical goal for desirable bias based on biological variation criteria. FC-Mixture glucose concentrations were 5.48 ± 0.65 mmol/L, 5.46 ± 0.6 mmol/L and 5.46 ± 0.64 mmol/L in tubes stored at RT for 1, 2 and 4 hours, respectively. Mean biases for FC-Mixture glucose in all time points reached optimal analytical goals. In the second study, the biases for LH and FH glucose compared to reference FC-Mixture glucose exceeded the preset analytical goals, regardless of the blood collection to centrifugation time interval.

Conclusions

FC-mixture tubes glucose concentrations were preserved up to 4h storage at RT. We confirmed that NaF alone does not allow immediate glycolysis inhibition in real life pre-centrifugation storage conditions (up to 340 minutes). FC-Mixture should be used exclusively for glucose determination in laboratories unable to implement the recommended blood samples’ treatment.Key words: glucose, pre-analytical phase, sodium fluoride, citrate acidification, stability  相似文献   
62.
Using the unique form of a composite counterstory culled from the experiences of 13 Black women at historically and predominantly White colleges and universities in a Western U.S. state, this paper explores the psychological tensions and silencing Black college women face as they navigate social constructions of their selfhood under a White gaze. This study centers these Black women’s voices through a tradition of storytelling and examines the ways they try to carve their own place by often engaging liberating, yet repressive, historically constructed STRONGBLACKWOMAN imagery to counteract equally silencing Angry Black Woman imagery. The historically and predominantly White institutional spaces within which these women study, live, and play exacerbate this tension, propelling them to model and rely upon stereotypically ‘positive’ representations of Black womanhood to deal with the pain of microaggressions. Altogether, these factors create instances of enhanced racial battle fatigue.  相似文献   
63.
This paper presents some of the elements which have been typical of music in different contexts and cultures, and describes an approach to musical phenomena which relates them to the intercultural and interdisciplinary dimension of lifelong education (music considered as a cultural good, an expression form, a field of creativity, an artistic production and an aesthetic experience). From the educational point of view, the aim is to form "multi-musical" individuals. In this framework are set the problem of musical identity and the need to spell out that identity in relation to stereotypes (popular music, classical music, folk music, etc.) and the differing shades of diversity. Particular attention needs to be given to the question of the universals seen in the psychology of music and the configuration of musical phenomena as structures which are organized hierarchically in several dimensions. In short, music in all its forms can help to form a dynamic, pluralist identity in the European context.  相似文献   
64.
Richard Griffith's The Movie Stars (Doubleday $25.00, $19.95 before Christmas, and $11.95 from the Literary Guild or Mainstroam Book Clubs)

Bernard Rosenberg and Harry Silverstein, The Real Tinsel (Macmillan, $9.95)

Andrew Sarris' Confessions of a Cultist: On The Cinema, 1955-69 (Simon and Schuster, $9.95, also available in paperback edition)

P. Adams Sitney's Film Culture Reader (Praeger, $4.95)

Anthony Schillaci and John M. Culkin's edited collection Films Deliver (Citation Press book 1583, $5.25)

International Film Guide Series  相似文献   
65.
Abstract

Knee injuries such as anterior cruciate ligament lesions and patellar tendonitis are very frequent in volleyball, and are often attributed to micro traumas that occur during the landing phase of airborne actions. The aim of the present study was to compare different jumping activities during official men's and women's volleyball games. Twelve top-level matches from the Italian men's and women's professional leagues were analysed. The jumps performed during the games were classified according to the landing technique used by the player (left or right foot or both feet together), court position, and ball trajectory. Chi-square analyses were performed to detect differences in landing techniques between the sexes, court positions, and trajectories when serving, attacking, blocking, and setting. Significant differences (P < 0.05) were found between the sexes for block, set, and spike but not for the jump serve. The frequency of landings on one foot was related to court position and the trajectory of the sets: when spiking faster sets, the players were more likely to use a one-footed landing. The present results should help coaches and physiotherapists to devise appropriate training and prevention programmes, and reveal the need for further detailed biomechanical investigations of the relationships between landings and knee injuries.  相似文献   
66.
67.
Over the last few years, increasing scholarly and media attention has been paid to the plight of undocumented immigrant college students. However, only a small fraction of undocumented youth actually moves on from high school to postsecondary opportunities. Indeed, the exclusion from financial aid eligibility and low family socioeconomic status severely limit undocumented students’ ability to matriculate to institutions of higher learning. But little is known about the ways in which school experiences shape postsecondary outcomes. This article focuses on the high school experiences of a sample of undocumented young adults and examines the ways in which school structures shape access to resources needed for postsecondary matriculation. In doing so, I argue that school-based networks are critical for success. However, these networks are fundamentally shaped by the school structure. This article draws from 78 in-depth life histories of undocumented Latino young adults in the Los Angeles metropolitan area. I incorporate a sample, stratified by educational experiences. The lived experiences of these young adults shed important light on the broader world in which they live and the ways in which immigration policies interact with school practices to shape success and failure.  相似文献   
68.
A computer- and Internet-based intervention was designed to influence several variables related to the prevention of pregnancy, STDs, and HIV in rural adolescents. Three-hundred and thirty-eight tenth-graders enrolled in two rural public high schools participated in this field experiment. Results indicate that students in the experimental school had greater knowledge, greater condom negotiation efficacy, greater situational efficacy, and more favorable attitudes toward waiting to have sex than students in the control school. In tandem, the results suggest that computer-based programs may be a cost-effective and easily replicable means of providing teens with basic information and skills necessary to prevent pregnancy, STDs, and HIV.  相似文献   
69.
Cyberbullying is the deliberate and repeated misuse of communication technology by an individual or group to threaten or harm others. Guided largely by the communication skills deficiency model and previous research on cyberbullying, this study examins the effects of several predictor variables (i.e., verbal aggression, sex, risky behaviors, parental monitoring, parental limits, technology use, and scope of Internet activities) on cyberbullying perpetration. A total of 1,606 incoming freshmen at a large southwestern university completed an online survey measuring all predictor and dependent variables under investigation. Overall, 35% of these individuals reported that they had cyberbullied at least one person during their senior year of high school. Results indicated that verbal aggression, risky behaviors, and cyberbullying victimization emerged as significant predictors of cyberbullying perpetration. These results have important theoretical and practical implications for those interested in developing cyberbullying prevention interventions.  相似文献   
70.
In the literature there is a lack of data about the development of top level athletes in cross-country mountain biking (XCO). The purpose of this study was to analyze anthropometric and physiological characteristics of some of the best XCO bikers aged between 13 and 16. The study involved 45 bikers (26 males and 19 females) belonging to a youth national team. The evaluations, consisting of anthropometric measures, incremental cycling tests (VO2max, PPO, P@RCP), and 30 s Wingate Tests (PMax, PMean), were conducted over a lapse of 4 years. Our findings showed in bikers, already at young age, a specific athletic profile advantageous for XCO performance. At the age of 16, just before entering the junior category and competing at international level, male and female bikers showed physiological values normalized to the body mass comparable to those reported in literature for high level athletes (VO2max>70 and >60 ml/kg/min, PPO >6.5 and >5.5 W/kg, respectively in males and females). The production of high power-to-weight ratios and high peaks of anaerobic power attests the presence of highly developed aerobic and anaerobic systems in young XCO cyclists reflecting the high physiological demand of this sport.  相似文献   
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