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61.
Andrew C. Faust Emily Guy Nidhu Baby Anthony Ortegon 《The Journal of emergency medicine》2018,54(5):681-684
Background
Methemoglobinemia is a well-recognized adverse drug reaction related to the use of certain local anesthetic agents. The mainstay of treatment for methemoglobinemia is i.v. methylene blue, along with provision of supplemental oxygen; however, methylene blue is listed as a category X teratogen. This poses an issue should methemoglobinemia develop during pregnancy.Case Report
A 35-year-old, 20-week and 5-day gravid female was transferred from an outpatient oral surgeon's office for hypoxia. She was undergoing extraction of 28 teeth and was administered an unknown, but “large” quantity of prilocaine during the procedure. Given this exposure, the concern was for methemoglobinemia. This was confirmed with co-oximetry, which showed 34.7% methemoglobin. The initial treatment plan was methylene blue; however, this drug is a category X teratogen. Thus, an interdisciplinary team deliberated and decided on treatment with high-dose ascorbic acid and transfusion of a single unit of packed red blood cells. The patient was managed with noninvasive ventilation strategies and a total of 8 g ascorbic acid. She was discharged on hospital day 3 with no obstetric issues noted.Why Should an Emergency Physician Be Aware of This?
Intravenous ascorbic acid appears to be a potential alternative to methylene blue in this patient population. The data surrounding teratogenicity of methylene blue are mostly related to intra-amniotic or intra-uterine administration. In life-threatening cases of methemoglobinemia during pregnancy, the benefits of i.v. methylene blue may outweigh the risks. 相似文献62.
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63.
64.
Consensus-recommendations for sirolimus in liver transplantation 总被引:2,自引:0,他引:2
Golling M Becker T Broelsch C Candinas D Faust D Fischer L Geissler E Graeb C Iberer F Klupp J Kraus T Müller AR Neuhaus P Strassburg CP Wolff M Zülke C Bechstein WO 《Zeitschrift für Gastroenterologie》2004,42(11):1333-1340
Sirolimus is an m-TOR inhibitor without renal side effects and potentially protects against the development of malignancy. Due to a higher incidence of complications in two trials and an official warning in the drug information, the use of Sirolimus in liver transplantation is limited. The participants of this consensus meeting had to analyse and evaluate the literature with respect to the potential role of Sirolimus in liver transplantation. This consensus statement follows the scheme normally employed for the presentation of guidelines including the grading of evidence (1a-5) and the extent of recommendation (A-C). Moreover, the consensus included the experience of the authors with respect to the handling of Sirolimus after liver transplantation. 相似文献
65.
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
66.
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
67.
P L Faust S Kornfeld J M Chirgwin 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(15):4910-4914
An 1110-base-pair cDNA clone for human cathepsin D was obtained by screening a lambda gt10 human hepatoma G2 cDNA library with a human renin exon 3 genomic fragment. Poly(A)+ RNA blot analysis with this cathepsin D clone demonstrated a message length of about 2.2 kilobases. The partial clone was used to screen a size-selected human kidney cDNA library, from which two cathepsin D recombinant plasmids with inserts of about 2200 and 2150 base pairs were obtained. The nucleotide sequences of these clones and of the lambda gt10 clone were determined. The amino acid sequence predicted from the cDNA sequence shows that human cathepsin D consists of 412 amino acids with 20 and 44 amino acids in a pre- and a prosegment, respectively. The mature protein region shows 87% amino acid identity with porcine cathepsin D but differs in having nine additional amino acids. Two of these are at the COOH terminus; the other seven are positioned between the previously determined junction for the light and heavy chains of porcine cathepsin D. A high degree of sequence homology was observed between human cathepsin D and other aspartyl proteases, suggesting a conservation of three-dimensional structure in this family of proteins. 相似文献
68.
69.
DM Clarkson 《Journal of medical engineering & technology》2013,37(3):125-131
An overview is provided of the scope and application of IEC TR 60825-9 in determination of hazards of non coherent optical radiation sources. Specific areas reviewed in detail include those relating to hazards of ultraviolet radiation, retinal thermal hazard and blue light photochemical hazard. The effect of spectral temperature on relative risk relating to retinal thermal hazard and blue light photochemical hazard are outlined. Assessment of risk factors of these hazards was determined using a range of measurement devices including spectral radiometer, broad band power meter and a locally developed device for determination of pulse profile of pulsed light sources. 相似文献
70.
Platelet concentrates were prepared at twice the normal concentration and stored at room temperature for 7 days in either standard bags (controls) or bags to which 1 or 2 g of Amberlite resin beads charged with dibasic phosphate had been added. The resin beads served as a buffer system by providing a "slow release" form of phosphate ions as well as by binding CO2 produced during platelet metabolism. Control platelets demonstrated rapid falls in pH, ATP content, morphology score, and thrombin-induced nucleotide release after 24 hr of storage with a fall in pH to less than 6.0 by day 3. Profound ultrastructural changes and a rise in pO2, suggesting loss of platelet viability, accompanied these changes. In contrast, the resin-stored platelets remained near normal after 24 hr of storage, with preservation of discoid morphology, 95% of ATP levels, excellent ultrastructural appearance, and evidence of continued oxygen consumption after 3 days of storage. Even after 7 days of storage, ATP levels remained greater than 50% of baseline and ultrastructurally intact platelets were seen. In the 1-g resin bags the pH remained at baseline levels (6.9-7.0), while there was a rise in pH in the 2-g resin bags. These results demonstrate the beneficial effects of maintaining a higher pH during platelet storage and provide a new approach to studying the metabolic changes that occur during longer term storage. 相似文献