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61.

Background

It is still uncertain whether or not avoidance to let disinfectant alcohol dry at the site of venipuncture is a source of spurious hemolysis when drawing venous blood.

Methods:

In a consecutive series of 52 outpatients referred for routine laboratory testing, venous blood was drawn by direct venipuncture with (odd group) or without (pair group) wiping 70% isopropyl alcohol at the site of venipuncture. A 3.5 mL evacuated tube with clot activator and gel separator was drawn from a vein of the upper limb, serum was immediately separated with standard centrifugation and tested for potassium, lactate dehydrogenase (LD), aspartate aminotransferase (AST) and hemolysis index (HI) on Roche Cobas.

Results:

No specimen was discarded for unsatisfactory venipuncture. No differences for age and gender were observed between groups. As regards the four parameters investigated, no significant differences could be observed between patients in whom blood was drawn with or without letting the alcohol dry. It is also noteworthy that no sample in both groups exceeded the conventional sample rejection threshold of cell-free hemoglobin.

Conclusions:

The results of our prospective, randomized study attest that failure to wipe alcohol at the site of venipuncture should not be considered as a potential source of spurious hemolysis when drawing blood.  相似文献   
62.
Current development education in the United Kingdom usually offers participants from developing countries studies of what development is or should be. These programmes are well suited to the needs of higher-level planners or policy researchers. They contrast markedly with the urgent need for the knowledge of and skills in how to undertake planned economic and social changes. This paper suggests a possible route towards a practical, professional training for middle-and lower-level personnel engaged in managing development and extension services. Briefly, the paper notes the lack of educational programmes aimed at practical training and middle-level staff in Britain; and the role of education in the process of development. Current difficulties for locating these programmes in the developing countries themselves are discussed, and the outline for a suitably practical programme, initially based in Britain, is proposed.  相似文献   
63.
This paper examines the relative importance and significance of the four technology enablers introduced by Davis (1989) in the technology acceptance model (TAM) (perceived ease of use, perceived usefulness, attitude towards using and behavioural intention) for use on four different levels of citizen engagement in e-government (null, publish, interact and transact). An extended technology acceptance model (TAM) is developed to test citizen engagement towards online e-government services from a sample of 307 citizens who used the benefits advisor tool within a Spanish City Hall. Although the proposed model follows TAM and explains the intention towards the actual use of e-government by postulating four direct determinants, “A, PU, PEOU and BI” have been considered as parallel processes, meaning that each can have separate influence in different levels of citizen engagement. To achieve this goal, a multinomial logistic regression is developed and tested to confirm the explanatory power of the four technology enablers on the four different levels of e-government. Our findings further suggest that in order to implement e-government, some of the enablers matter more than others to move from one level of citizen engagement to another. The main contribution of the paper is to question the use of existing models which seek to represent the relationship between technology enablers and the adoption of e-government services without considering their impacts on citizens’ engagement. The implications of the findings are discussed and useful insights are provided in relation to policy recommendations geared to create appropriate conditions to build citizens’ engagement intent of use of e-government services.  相似文献   
64.
The present study integrates two concepts: the notion of opinionleadership, as conceptualized and measured by the Strength ofPersonality (SP) scale, and the agenda-setting process. Thus,we suggest and test a two-step flow model in which certain individuals,the influentials, identify emerging issues in the mass mediaand then diffuse these issues to others via their personal networks.Based on a series of six national surveys conducted in Germany(1990) measuring issue salience and various personal characteristics,this study highlights the role certain individuals play in theemergence of the public agenda. The degree to which individualscan be influenced, measured by the SP scale, is found to bea powerful predictor of the formation of personal agendas, withhigh SP individuals differing from others in their identificationof emerging public issues. However, the analysis reveals thecomplexity of these relationships: they depend on the obtrusivenessof the issue, and they vary over time and location (East orWest Germany). The findings encourage the empirical pursuitof the suggested ‘two-step flow model’ as appliedto the agenda-setting process.  相似文献   
65.
Two studies were carried out during university workshops, and analyzed the effects of resource interdependence on student‐student interactions, and the impact of these interactions on performance. Students worked cooperatively, either on complementary information (positive resource interdependence) or on identical information (resource independence). In Study 1, analysis of videotaped interactions revealed that working on complementary information produced more positive interactions; however this was not sufficient to prevent students who had no direct access to the information from being disadvantaged, because of informational dependence. In Study 2, with simpler texts allowing better information transmission, performance was favored when students worked on complementary information. Moreover, working on identical information not only enhanced confrontations of point of views, it also elicited competence threat. Further analysis revealed that competence threat mediated resource interdependence effect on performance. Discussion provides insights into the conditions in which different cooperative methods can benefit learning.  相似文献   
66.
It is ironical that developments in the field of education call for teachers to differentiate instruction as a pre-requisite for effective learning,while teacher education and continuing professional development adhere to a one-size-fits-all philos- ophy. In general,professional development initiatives are part of'reform packages'with decisions about what,when,and  相似文献   
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Efforts to break the link between the school type attended and the qualification awarded are seen an important step in the modernization of Germany??s tracked secondary school system. However, it remains disputed whether these efforts have reduced social disparities or in fact increased them. This study examined the transition from lower secondary education in academic- and intermediate-track schools to upper secondary education in general and vocational gymnasium schools in the state of Baden-Württemberg. When indicators of parental social background and school-leaving qualifications were controlled, the opening of upper secondary education was found to be associated with a decrease in the social selectivity of upper secondary education for intermediate-track students. At the same time, for those intermediate-track students who were entitled to enter upper secondary education, social background had predictive effects on the transition decision; however, the overall size of these effects was low.  相似文献   
70.
The effects of treadmill running on impact acceleration were examined together with the interaction between running surface and runner's fatigue state. Twenty recreational runners (11 men and 9 women) ran overground and on a treadmill (at 4.0 m/s) before and after a fatigue protocol consisting of a 30-minute run at 85% of individual maximal aerobic speed. Impact accelerations were analysed using two lightweight capacitive uniaxial accelerometers. A two-way repeated-measure analysis of variance showed that, in the pre-fatigue condition, the treadmill running decreased head and tibial peak impact accelerations and impact rates (the rate of change of acceleration), but no significant difference was observed between the two surfaces in shock attenuation. There was no significant difference in acceleration parameters between the two surfaces in the post-fatigue condition. There was a significant interaction between surface (treadmill and overground) and fatigue state (pre-fatigue and post-fatigue). In particular, fatigue when running overground decreased impact acceleration severity, but it had no such effect when running on the treadmill. The effects of treadmill running and the interaction need to be taken into account when interpreting the results of studies that use a treadmill in their experimental protocols, and when prescribing physical exercise.  相似文献   
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