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161.
Influence of blood specimen collection method on various preanalytical sample quality indicators 总被引:1,自引:0,他引:1
Tester F. Ashavaid Sucheta P. Dandekar Bhamini Keny Vishaal R. Bhambhwani 《Indian journal of clinical biochemistry : IJCB》2008,23(2):144-149
Preanalytical errors contribute to a large proportion of total laboratory errors. In order to achieve continuous laboratory
improvement, it is important to focus on all phases of patient specimen testing i.e. preanalytical, analytical and post-analytical.
With large variations in the way venous blood specimens are collected using diverse devices in the country, the effect of
such practices on specimen quality is not known. The purpose of this study was to monitor fourteen specimen preanalytical
quality indicators in order to compare the usage of evacuated blood collection devices with needle and syringe open collection
using either disposable tubes or re-washed glass vials. The study involved 26638 patient specimens assessed over a period
of 6 months. The results demonstrated that evacuated closed blood collection resulted in an approximate 100-fold reduction
in the incidence of hemolysis in samples. Similarly, there was a 200-fold reduction in incidence of insufficient specimen
quantity while using evacuated collection system. It was also found that incidence of specimen contamination, improper volume
of sample collected, and specimen spillage was also lower when the evacuated collection system was used. Further, it was also
observed that the facility with a laboratory information system demonstrated much lower specimen identification and related
errors. The observed results clearly demonstrate that the usage of the evacuated blood collection system resulted in improvement
of preanalytical specimen quality as compared to needle and syringe usage. 相似文献
162.
163.
Seema Bhargava Meghaa Shanta Bhargava Eishaan Kamta Bhargava LM Srivastava 《Indian journal of clinical biochemistry : IJCB》2016,31(2):148-151
Hyperhomocysteinemia (HHCY) has been demonstrated to affect cochlear microvasculature as well as cochlear epithelial cells directly, with a resultant alteration of the expression of matrix metalloproteinases (MMPs) and their inhibitors, tissue inhibitors of metalloproteinases (TIMPs). Hence, ascertaining the optimum concentration of MMPs and TIMPs in the cochlea could help to inhibit hearing loss due to HHCY by the administration of appropriate MMP inhibitors, Since infections/inflammations as well as ototoxic antibiotics have a similar mechanism of otic pathology, the cochlear damage they cause could also be similarly prevented. 相似文献
164.
165.
Spelling skills have been identified as one of the major barriers to written text production in young English writers. By contrast oral language skills and text generation have been found to be less influential in the texts produced by beginning writers. To date, our understanding of the role of spelling skills in transparent orthographies is limited. The current study addressed this gap by examining the contribution of spelling, oral language and text generation skills in written text production in Italian beginner writers. Eighty-three children aged 7–8 years participated in the study. Spelling, lexical retrieval, receptive grammar, and written sentence generation and reformulation skills were assessed and children were asked to write a text on a set topic. A factor analysis revealed that the children’s written text production was captured by three factors: productivity, complexity and accuracy. In contrast to results from children learning to write in opaque orthographies, such as English, this study showed that receptive grammar and written sentence generation skills accounted for significant variance in measures of productivity, complexity and accuracy in Italian children’s written text production. Spelling skills contributed to text accuracy and quality and explained more variance than receptive grammar in microstructural accuracy. By contrast, oral grammatical skills explained more variance in text quality than spelling. The current study shows the differential impact of language systems, such as Italian, on written text production. Implications for assessment and instruction are outlined. 相似文献
166.
Blended forms of learning have become increasingly popular. Learning activities within these environments are supported by a large variety of online and face-to-face interventions. However, it remains unclear whether these blended environments are successful, and if they are, what makes them successful. Studies suggest that blended learning challenges the self-regulatory abilities of learners, though the literature does little to explain these findings; nor does it provide solutions. In particular, little is known about the attributes that are essential to support learners and how they should guide course design. To identify such attributes and enable a more thoughtful redesign of blended learning environments, this systematic literature review (n?=?95) examines evidence published between 1985 and 2015 on attributes of blended learning environments that support self-regulation. The purpose of this review is therefore to identify and define the attributes of blended learning environments that support learners’ self-regulatory abilities. Seven key attributes were found (authenticity, personalization, learner-control, scaffolding, interaction, cues for reflection and cues for calibration). This review is the first to identify and define the attributes that support self-regulation in blended learning environments and thus to support the design of blended learning environments. This study may serve to facilitate the design of blended learning environments that meet learners’ self-regulatory needs. It also raises crucial questions about how blended learning relates to well-established learning theories and provides a basis for future research on self-regulation in blended learning environments. 相似文献
167.
168.
The introduced study represents methodology and results of research focused on utilization of interactive whiteboard as didactic technology mediating information through multimedia worksheets applied in education process in pre-primary education. Its aim was to determine whether it can significantly increase the level of children’s acquired knowledge in the field of technical skills education and whether it can positively influence the development of children’s creative skills as a sign of their motivation. We observe that this issue in the way it is theoretically and practically established in this study can contribute by proposing education standards and set of multimedia worksheets in the technical field in Slovak pre-primary education. 相似文献
169.
170.
Rajesh Kumar Kori Manish Kumar Singh Abhishek Kumar Jain Rajesh Singh Yadav 《Indian journal of clinical biochemistry : IJCB》2018,33(4):372-381
The problem of pesticides is not new and its exposure to human due to indiscriminate use is largely associated with the health related problems including neurotoxicological alterations. High levels of pesticide residues and their metabolites in the dietary constituents, food materials, maternal blood, cord blood, placenta breast milk have been reported and linked to alterations in birth weight, crown heel length, head circumference, mid-arm circumference and ponderal index of the neonates. Epidemiological studies have suggested that exposure of pesticide to human could be a significant risk factor for neurological disorders, including Parkinson’s disease, Alzheimer’s disease and multiple sclerosis. Cholinergic and non-cholinergic dysfunctions in pesticide exposed population, especially in children have also been frequently reported in recent years. Developmental neurotoxicity is another concern in the area where pregnant are more prone towards its exposure and which results in the abnormalities in the fetus. In view of the increasing risk of human health through pesticide exposure, the present review has been focused on the studies pertaining to pesticide induced neurochemical alterations and associated behavioral abnormalities in farm workers which could establish a possible link between the its exposure and associated health hazards. 相似文献