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51.
Narrow QRS tachycardia with apparent concentric atrial activation pattern: What is the mechanism? 下载免费PDF全文
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Monique Lhussier HND MSc PhD Simon Eaton BMedSci BMBS FRCP DM CertMEd Natalie Forster BA PGCert Mathew Thomas BA Sue Roberts MBBS MSc FRCP Susan M Carr BA MSc PhD 《Health expectations》2015,18(5):605-624
Objective
This article focuses on approaches within clinical practice that seek to actively involve patients with long‐term conditions (LTCs) and how professionals may understand and implement them. Personalized care planning is one such approach, but its current lack of conceptual clarity might have impeded its widespread implementation to date. A variety of overlapping concepts coexist in the literature, which have the potential to impair both clinical and research agendas. The aim of this article is therefore to explore the meaning of the concept of care planning in relation to other overlapping concepts and how this translates into clinical practice implementation.Methods
Searches were conducted in the Cochrane database for systematic reviews, CINHAL and MEDLINE. A staged approach to conducting the concept mapping was undertaken, by (i) an examination of the literature on care planning in LTCs; (ii) identification of related terms; (iii) locating reviews of those terms. Retrieved articles were subjected to a content analysis, which formed the basis of our concept maps. (iv) We then appraised these against knowledge and experience of the implementation of care planning in clinical practice.Results and Conclusions
Thirteen articles were retrieved, in which the core importance of patient‐centredness, shared decision making and self‐management was highlighted. Literature searches on these terms retrieved a further 24 articles. Our concept mapping exercise shows that whilst there are common themes across the concepts, the differences between them reflect the context and intended outcomes within clinical practice. We argue that this clarification exercise will allow for further development of both research and clinical implementation agendas. 相似文献54.
55.
C J Oddie E H Blaine S D Bradshaw J P Coghlan D A Denton J F Nelson B A Scoggins 《The Journal of endocrinology》1976,69(3):341-348
Peripheral blood corticosteroid levels were determined in nine species of Australian marsupial (Eastern grey kangaroo, black-tailed, Bennett's and pademelon wallabies, quokka, wombat, koala and Western native and tiger cats), one species of monotreme (echidna) and one placental Australian mammal (dingo). Animals were obtained or bled with minimal disturbance and came from areas considered to have adequate sodium content of the vegetation. Aldosterone, corticosterone, cortisol, 11-deoxycorticosterone and 11-deoxycortisol were measured and levels found to be similar to five introduced eutherian species (sheep, cow, dog, fox and man) with the exception of the koala and the wombat. Cortisol was the predominant corticosteroid, except in the koala, which produced corticosterone in relatively the greatest quantity, and the wombat which produced more 11-deoxycortisol. Steroid levels were generally low in the wombat. ACTH administered to the koala changed its pattern of corticosteroid secretion from predominantly corticosterone to cortisol. In the dingo, administration of ACTH caused rises in corticosteroid levels similar to those seen in most other eutherian mammals. 相似文献
56.
Smyth AE MacGregor AJ Mukerjee D Brough GM Black CM Denton CP 《Rheumatology (Oxford, England)》2003,42(6):732-738
OBJECTIVES: In scleroderma, outcome measures such as skin score provide only limited information about the functional impact of the disease. The requirement for validated and convenient instruments that reliably reflect disease morbidity is now recognized. This study compares the Disability Index of the Health Assessment Questionnaire (HAQ-DI) with two more recently developed scleroderma-specific tools: scleroderma-visual analogue scales (scleroderma-VAS) and the UK scleroderma Functional Score (UKFS). In addition, the use of clinical and laboratory measures as predictors of disease severity have been examined. METHODS: One hundred and fifteen consecutive patients were studied. Subjects completed the 20-item HAQ-DI, the scleroderma-VAS and a questionnaire related to hand and muscle function (UKFS). Clinical details, measurement of maximal hand-spread, fist-closure and investigations for internal organ involvement were recorded. RESULTS: Over 68% of patients with diffuse disease had moderate to severe disease on the UKFS, compared with 44% with limited disease. The mean UKFS in diffuse disease was 14.7 (s.d. 9.1) and 10.6 (s.d. 8.5) in the limited subset (P=0.02). The mean HAQ-DI in diffuse disease was 1.23 (s.d. 0.77) and 0.79 (s.d. 0.75) in the limited subset (P=0.005). The HAQ-DI showed significant correlation with UKFS (r=0.9; P < 0.001). Several clinical and laboratory measures were associated with higher HAQ-DI and UKFS. CONCLUSIONS: This is the first comparative study of the UKFS and the HAQ-DI. These data show a strong correlation between assessment methods. Higher scores correlated with clinical and laboratory indicators of severe disease. Used together, these inexpensive tools assess general and organ-specific symptoms, as well as functional limitation. 相似文献
57.
Identification of an oncogenic form of the thrombopoietin receptor MPL using retrovirus-mediated gene transfer 总被引:3,自引:3,他引:3
Onishi M; Mui AL; Morikawa Y; Cho L; Kinoshita S; Nolan GP; Gorman DM; Miyajima A; Kitamura T 《Blood》1996,88(4):1399-1406
Thrombopoietin and its receptor (MPL) are important regulators of megakaryopoiesis. We have identified an activating mutation of MPL using a combination of a retrovirus-mediated gene transfer and polymerase chain reaction-driven random mutagenesis. This point mutation causes a single amino acid substitution from Ser498 to Asn498 in the transmembrane region and abrogates factor-dependency of all interleukin-3-dependent cell lines tested. Murine interleukin-3- dependent Ba/F3 cells expressing the mutated but not the normal form of MPL were tumorigenic when transduced into syngeneic mice. Analysis of intracellular signaling pathways indicated that the mutant MPL protein constitutively activated two distinct signaling pathways, SHC-Raf-MAPK and JAK2-STAT3/STAT5. 相似文献
58.
Role of copper in mitochondrial iron metabolism 总被引:1,自引:1,他引:1
Heme synthesis by copper-deficient cells was investigated to elucidate the nature of the defect in intracellular iron metabolism. Iron uptake from transferrin by copper-deficient reticulocytes was 52% of normal, and the rate of heme synthesis was 33% of normal. Hepatic mitochondria isolated from copper-deficient animals were deficient in cytochrome oxidase activity and failed to synthesize heme from ferric iron (Fe III) and protoporphyrin at the normal rate. The rate of heme synthesis correlated with the cytochrome oxidase activity. Heme synthesis from Fe(III) and protoporphyrin by normal mitochondria was enhanced by succinate and inhibited by malonate, antimycin A, azide, and cyanide. It is proposed that an intact electron transport system is required for the reduction of Fe(III), thereby providing a pool of ferrous iron (Fe II) for protoheme and heme a synthesis. 相似文献
59.
Experimental narrowing of the main renal artery to produce hypertension increases the aorta-glomerular capillary pressure difference and vascular resistance. This article examines the hypothesis that hypertension also may be caused by structural changes that narrow intrarenal blood vessels, similarly increasing preglomerular vascular resistance and the aortic-glomerular capillary pressure gradient. There is evidence of both wall hypertrophy and lumen narrowing of the preglomerular arteries in spontaneously hypertensive rats, with increased preglomerular resistance and aortic-glomerular capillary pressure difference. We have also attempted to induce structural changes in renal-preglomerular vessels experimentally by infusing angiotensin II at low doses (0.5 to 4.5 ng/kg per minute) into the renal artery of Sprague-Dawley rats and greyhound dogs for up to 4 weeks. This angiotensin II infusion produced apparent dose-related effects on preglomerular vessel structure and hypertension. The possibility that hypertension may be induced by structural changes in preglomerular resistance vessel walls, by simulation of the hemodynamic effects of main renal artery stenosis, deserves further investigation. 相似文献
60.
Elharith M. Ahmed Frederick J. Barrera Edward A. Early Michael L. Denton C.D. Clark Dhiraj K. Sardar 《Computers in biology and medicine》2013,43(12):2278-2286
Since its invention in the early 1960s, the laser has been used as a tool for surgical, therapeutic, and diagnostic purposes. To achieve maximum effectiveness with the greatest margin of safety it is important to understand the mechanisms of light propagation through tissue and how that light affects living cells. Lasers with novel output characteristics for medical and military applications are too often implemented prior to proper evaluation with respect to tissue optical properties and human safety. Therefore, advances in computational models that describe light propagation and the cellular responses to laser exposure, without the use of animal models, are of considerable interest. Here, a physics-based laser–tissue interaction model was developed to predict the dynamic changes in the spatial and temporal temperature rise during laser exposure to biological tissues. Unlike conventional models, the new approach is grounded on the rigorous electromagnetic theory that accounts for wave interference, polarization, and nonlinearity in propagation using a Maxwell's equations-based technique. 相似文献