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61.

Introduction

The validation process is essential in accredited clinical laboratories. Aim of this study was to validate five kinds of serum vacuum tubes for routine clinical chemistry laboratory testing.

Materials and methods:

Blood specimens from 100 volunteers in five diff erent serum vacuum tubes (Tube I: VACUETTE®, Tube II: LABOR IMPORT®, Tube III: S-Monovette®, Tube IV: SST® and Tube V: SST II®) were collected by a single, expert phlebotomist. The routine clinical chemistry tests were analyzed on cobas® 6000 module. The significance of the diff erences between samples was assessed by paired Student’s t-test after checking for normality. The level of statistical significance was set at P < 0.005. Finally, the biases from Tube I, Tube II, Tube III, Tube IV and Tube V were compared with the current desirable quality specifications for bias (B), derived from biological variation.

Results and conclusions:

Basically, our validation will permit the laboratory or hospital managers to select the brand’s vacuum tubes validated according him/her technical or economical reasons, in order to perform the following laboratory tests: glucose, total cholesterol, high density lipoprotein-cholesterol, triglycerides, total protein, albumin, blood urea nitrogen, uric acid, alkaline phosphatise, aspartate aminotransferase, gamma-glutamyltransferase, lactate dehydrogenase, creatine kinase, total bilirubin, direct bilirubin, calcium, iron, sodium and potassium. On the contrary special attention will be required if the laboratory already performs creatinine, amylase, phosphate and magnesium determinations and the quality laboratory manager intend to change the serum tubes. We suggest that laboratory management should both standardize the procedures and frequently evaluate the quality of in vitro diagnostic devices.  相似文献   
62.
The majority of Internet users search for medical information online; however, many do not have an adequate medical vocabulary. Users might have difficulties finding the most authoritative and useful information because they are unfamiliar with the appropriate medical expressions describing their condition; consequently, they are unable to adequately satisfy their information need. We investigate the utility of bridging the gap between layperson and expert vocabularies; our approach adds the most appropriate expert expression to queries submitted by users, a task we call query clarification. We evaluated the impact of query clarification. Using three different synonym mappings and conducting two task-based retrieval studies, users were asked to answer medically-related questions using interleaved results from a major search engine. Our results show that the proposed system was preferred by users and helped them answer medical concerns correctly more often, with up to a 7 % increase in correct answers over an unmodified query. Finally, we introduce a supervised classifier to select the most appropriate synonym mapping for each query, which further increased the fraction of correct answers (12 %).  相似文献   
63.
The relationship between junior boys' tennis success, as measured by a top 20 International Tennis Federation's Junior Circuit (ITFJC) ranking, and subsequent ranking accomplishments in professional men's tennis is discussed. The names, countries, and birthdates of all players to achieve a top 20 ITFJC boys' year-end ranking from 1992 to 1998 were recorded. The progress of these players through the professional ranks was then tracked to the end of 2004. Results indicate that 91% of top 20-ranked boys achieved a professional men's ranking, while a stepwise regression analysis revealed junior ranking (JR) to be a predictor of future, professional ranking (beta = 0.232, r(2) = 0.054, p < 0.05). A regression equation [predicted professional rank = 78.17 + 6.31*(JR)] accounted for a significant amount of variance in professional ranking. For male players, therefore, the achievement of a top 20 junior ranking appears to be a reasonable yardstick for future, professional success. The type of surface upon which junior players develop their games was also shown to influence professional ranking highs, with play on clay courts or a combination of clay and hard courts helping to produce higher, professionally ranked players than hard court play alone (p< or = 0.01).  相似文献   
64.
A new device called Buzzy® has been recently presented that combines a cooling ice pack and a vibrating motor in order to relieve the venipuncture pain. The aim of this study was to evaluate the impact of Buzzy® use during diagnostic blood specimen collection by venipuncture for routine immunochemistry tests. Blood was collected from 100 volunteers by a single, expert phlebotomist. A vein was located on the left forearm without applying tourniquet, in order to prevent any interference from venous stasis, and blood samples were collected using a 20-G straight needle directly into 5 mL vacuum tubes with clot activator and gel separator. In sequence, external cold and vibration by Buzzy® was applied on the right forearm—5 cm above the chosen puncture site—for 1 min before venipuncture and continued until the end of the same procedure already done in the left forearm. The panel of tests included the following: glucose, total cholesterol, HDL-cholesterol, triglycerides, total protein, albumin, c-reactive protein, urea, creatinine, uric acid, alkaline phosphatase, amylase, AST, ALT, g-glutamyltransferase, lactate dehydrogenase, creatine kinase, total bilirubin, phosphorus, calcium, magnesium, iron, sodium, potassium, chloride, lipase, cortisol, insulin, thyroid-stimulating hormone, total triiodothyronine, free triiodothyronine, total thyroxine, free thyroxine and haemolysis index. Clinically significant differences between samples were found only for: total protein, albumin and transferrin. The Buzzy® can be used during diagnostic blood specimens collection by venipuncture for the majority of the routine immunochemistry tests. We only suggest avoiding this device during blood collection when protein, albumin and transferrin determinations should be performed.  相似文献   
65.
Reading and Writing - Text generation—the mental translation of ideas into language at word, sentence, and discourse levels—involves oral language abilities. However, oral language...  相似文献   
66.
A low-cost device for registration-free quantitative phase microscopy (QPM) based on the transport of intensity equation of cells in continuous flow is presented. The method uses acoustic focusing to align cells into a single plane where all cells move at a constant speed. The acoustic focusing plane is tilted with respect to the microscope’s focal plane in order to obtain cell images at multiple focal positions. As the cells are displaced at constant speed, phase maps can be generated without the need to segment and register individual objects. The proposed inclined geometry allows for the acquisition of a vertical stack without the need for any moving part, and it enables a cost-effective and robust implementation of QPM. The suitability of the solution for biological imaging is tested on blood samples, demonstrating the ability to recover the phase map of single red blood cells flowing through the microchip.  相似文献   
67.
The aim of this brief communication is to reply to a letter by Kosmulski (Journal of Informetrics 6(3):368–369, 2012), which criticizes a recent indicator called “success-index”. The most interesting features of this indicator, presented in Franceschini et al. (Scientometrics, in press), are: (i) allowing the selection of an “elite” subset from a set of publications and (ii) implementing the field-normalization at the level of an individual publication. We show that the Kosmulski's criticism is unfair and inappropriate, as it is the result of a misinterpretation of the indicator.  相似文献   
68.
69.
This paper provides new insights into understanding the causes of deterioration of the Corbii de Piatra rupestrian church and shows the significance of studying the geological environment of historical rock-cut settlements when undertaking preservation and restoration actions. The Corbii de Piatra church is one of the few rupestrian churches remaining in Romania and is an important part of the country's heritage. The church is carved in a stratum of polymictic sandstone of Oligocene age, which is part of the Getic Depression, located in the southern part of the South Carpathians. In the 14th century the interior walls of the church were decorated with mural paintings of a high artistic value. Over the centuries, the church's walls and mural paintings have been negatively affected by a series of physicochemical processes. These processes were studied through field investigations and laboratory analyses carried out between October 2007 and November 2010. The investigations revealed that tectonic fissuring and the structural anisotropy of the rock facilitate the infiltration of meteoric water through the walls into the interior of the church, from north to south, maintaining a high-level of humidity in the northern wall and in the interior of the church. The most harmful effects observed were: (i) the partial hydrolysis of the feldspars through reaction with water from the pores, producing a friable mass of phyllosilicates which led to a superficial disaggregation of the rock and to a diminished cohesion between the rock and the mortar of the fresco, (ii) the reprecipitation of the gypsum as efflorescences on the northern wall and ceiling, covering the mural painting in localized areas, as a result of the transportation of the gypsum by water from the upper strata, (iii) the alteration of the cinnabar pigment, as a result of water penetration by diffusion through the fresco from the wet rock to the pictorial layer (the secondary effect observed being the formation of sulfuric acid, which further reacted with the carbonate from the fresco to form gypsum), (iv) the development of biotic crusts, predominately algal, on the interior wet walls, which, facilitated by the permanent high humidity and the semi-obscurity of the interior of the church, have covered large surfaces of the fresco. Compared to the interior, the exterior vertical walls have been exposed to prolonged daily and seasonal variations of temperature and humidity. These variations have caused repeated variations in the volume of the sandstone, leading to contraction fissuring and peeling of the vertical walls. Any future procedures that might be used to conserve the church should strive to reduce the humidity of the sandstone in the interior walls.  相似文献   
70.
According to Michel Foucault, modernity is predicated on the emergence of an instrumental idea of knowledge, which does not affect the constitution of the individual as a subject. This article aims to explore this thesis in the context of British Higher Education through a problematization of widening participation policies, and how they have been increasingly constructed in economic-instrumental terms. This approach suggests two main considerations within the framework of Foucault's argument. First, widening participation initiatives have contributed to reinforce an idea of knowledge as an instrumental set of notions external to the subject rather than a process of transformation of the self. Second, widening participation initiatives have been dominated by a neoliberal approach to the problem of inequality which has turned students into seemingly equal consumers of knowledge. However, it will be argued, this approach contributes to reproduce in different ways the inequality gap between students of different socioeconomic backgrounds.  相似文献   
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