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201.
One of the many facets of educational psychology to which the nurse teacher should give consideration is the nature of human knowledge. An individual interacting with his environment forms ideas or concepts which coalesce to create a mental organisation, or ‘conceptual framework’, that is unique to that individual. The nurse teacher takes account of this uniqueness of such a framework by assessing the conceptual position occupied by each of his learners, and by adapting his teaching strategies accordingly. Failure to do this can result in the inadequate learning of new ideas or concepts, in particular complex concepts such as are found in nursing. With reference to certain of the literature it is shown that the direct teaching of concepts does not occur, while the effectiveness of active learner participation is demonstrated as aiding the ‘personalisation’ of newly offered concepts, which then become truly part of the learner's conceptual framework. 相似文献
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Elizabeth R Hooker Bram CJ van der Eerden Huibert A Pols Albert Hofman Johannes PTM van Leeuwen Andre G Uitterlinden Carrie M Nielson M. Carola Zillikens 《Journal of bone and mineral research》2017,32(6):1182-1193
Extreme phosphate levels (P) have been associated with mineralization defects and increased fracture risk. Whether P within normal range is related to bone health in the general population is not well understood. To investigate the association of P with bone mineral density (BMD) and fracture risk, we assessed two population‐based cohorts: the Dutch Rotterdam Study (RS‐I, RS‐II, RS‐III; n = 6791) and the US Osteoporotic Fractures in Men (MrOS; n = 5425) study. The relationship of P with lumbar spine (LS) and femoral neck (FN) BMD was tested in all cohorts via linear models; fracture risk was tested in RS‐I, RS‐II, and MrOS through Cox models, after follow‐up of 8.6, 6.6, and 10.9 years, respectively. Adjustments were made for age, body mass index, smoking, serum levels of calcium, potassium, 25‐hydroxyvitamin D, estimated glomerular filtration rate (eGFR), FN‐BMD, prevalent diabetes, and cardiovascular disease. Additional adjustments were made for phosphate intake, parathyroid hormone, and fibroblast growth factor 23 levels in MrOS. We further stratified by eGFR. Results were pooled through study‐level meta‐analyses. Hazard ratios (HR) and betas (β) (from meta‐analyses) are expressed per 1 mg/dL P increase. P was positively associated with fracture risk in men and women from RS, and findings were replicated in MrOS (pooled HR all [95% CI]: 1.47 [1.31–1.65]). P was associated with fracture risk in subjects without chronic kidney disease (CKD): all (1.44 [1.26–1.63]) and in men with CKD (1.93 [1.42–2.62]). P was inversely related to LS‐BMD in men (β: –0.06 [–0.11 to –0.02]) and not to FN‐BMD in either sex. In summary, serum P was positively related to fracture risk independently from BMD and phosphate intake after adjustments for potential confounders. P and LS‐BMD were negatively related in men. Our findings suggest that increased P levels even within normal range might be deleterious for bone health in the normal population. © 2017 American Society for Bone and Mineral Research. 相似文献
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MT Clandinin JE Van Aerde A Parrott CJ Field AR Euler E Lien 《Acta paediatrica (Oslo, Norway : 1992)》1999,88(8):890-896
This study evaluated preterm infants of less than 2.3 kg birth weight fed commercial formula (Preemie SMA®) devoid of arachidonic acid (AA) and docosahexaenoic acid (DHA) and compared this control group with similar infant groups fed one of three formulas containing a range of 0.32-1.1% AA and 0.24-0.75% DHA in the fat component of the formula. An analogous group of infants fed on their mothers' breast milk and a breast milk fortifier was also studied. Individual lipoprotein fractions were isolated from blood samples collected at 12 d of age and after a further 4 wk of feeding. The fatty acid content of individual lipid components, isolated from each lipoprotein fraction was quantitatively determined in order to identify change in marker pools of essential fatty acid. The high density lipoproteins (HDL) and low density lipoproteins (LDL) phospholipid and cholesterol ester fractions contain most of the AA and DHA found in the lipoprotein fractions (total of 0.49% and 0.35%, respectively). Infants fed a formula without AA and DHA showed a reduction in AA level in the phospholipid fraction of all lipoproteins and in the HDL and LDL cholesterol ester fraction. A reduced level of DHA was also observed primarily in the lipoprotein phospholipid fraction in comparison with infants fed breast milk or infant formula containing AA and DHA. Supplementing infant formula with increasing levels of AA and DHA produced a clear dose response in the level of AA found in the HDL and LDL phospholipid fraction. From comparison of the fatty acid levels present in the lipoproteins it appears that a formula level of 0.49% AA and 0.35% DHA provides sufficient levels of these fatty acids to achieve a similar fatty acid content to that of infants fed breast milk for the major lipoprotein fractions examined. 相似文献
206.
Adverse drug reactions and the package insert 总被引:1,自引:0,他引:1
CJ Coté 《Acta paediatrica (Oslo, Norway : 1992)》1999,88(9):925-927
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Eloise CJ Carr 《Journal of clinical nursing》2009,18(1):124-131
Aim. The purpose of this paper is to critically explore the sequential explanatory mixed method research design and how it can enhance our understanding of pain management. Background. The general prevalence of pain after surgery has not changed significantly over several decades despite the widespread introduction of new pain relieving technologies. The majority of postoperative pain studies use quantitative methods which offer little understanding of the underlying processes of care. Understanding can be illuminated by using an explanatory mixed method research design. Design. Discursive paper. Method. This paper focuses on the methodological considerations when using a mixed method design. Two previously published mixed methods studies illustrate how findings can inform practice. In the first, 85 women undergoing surgery completed questionnaires to measure pain, anxiety and depression. Telephone interviews explored their pain experiences. The second study considered frequency and patterns of anxiety in the immediate pre and postoperative period. Semi‐structured telephone interviews, identified contributing events/situations amenable to nursing intervention. Discussion. Reasons for growing popularity, criticisms, paradigmatic considerations and epistemological roots of pragmatism are explored. The two explanatory mixed method studies provide examples of these studies and how ‘inferences’ from quantitative and qualitative data can inform practice. Conclusion. This paper connects quantitative and qualitative data, drawing on two research studies, to give greater understanding to the management of pain. Knowledge of the processes responsible for inadequate pain management can be illuminated by using explanatory mixed methods research designs. Relevance to clinical practice. Nursing requires knowledge which reflects the complexity of human health. The explanatory mixed method study can elucidate the problem under scrutiny, e.g. prevalence of pain or anxiety. The qualitative phase can generates an understanding of contributing factors and insights for care delivery. The implicit desire to change and influence practice makes it relevant for those closely aligned to practice. 相似文献
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210.
Granulocyte colony-stimulating factor (G-CSF) can elicit responses that include proliferation, granulocytic differentiation, and activation of cellular functions in target cells. The biochemical pathways responsible for transduction of these signals from the G-CSF receptor (G-CSFR) have not been defined. In this report, we show that, in murine (NFS-60) and human (OCI-AML 1) myeloid leukemia cell lines and in murine pro-B-lymphocytic cells, BAF/B03, transfected with the murine G- CSFR, proliferative responses to G-CSF are associated with rapid activation of p42 and p44 MAP kinases and p21ras. Truncation of the cytoplasmic portion of the murine G-CSFR at residue 646 but not at residue 739 abolished G-CSF-induced stimulation of cellular proliferation as well as activation of MAP kinase and p21ras in transfected BAF/B03 cells. G-CSF-induced granulocytic differentiation of the murine leukemic cell line 32DC13(G) occurred in the absence of detectable activation of p42 MAP kinase. Nonproliferative responses to G-CSF in the human promyelocytic cell line HL-60 and in human neutrophils were similarly associated with no MAP kinase activation. These results imply that differing cellular effects of G-CSF may be involve the recruitment of differing signal transduction pathways with the p21ras/MAP kinase pathway being limited to proliferative responses. 相似文献