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81.
WBG Macdonald AP Patrikeos RI Thompson BD Adler AA Van Der Schaaf 《Journal of Medical Imaging and Radiation Oncology》2005,49(1):32-38
The present study compared the accuracy of ventilation perfusion scintigraphy (VQS) and CT pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism. This was a prospective observational study of 112 patients with suspected pulmonary embolism (PE) who could be studied with both investigations within 24 h. Results were compared to final diagnosis at completion of 6-month follow up, using receiver operating characteristic (ROC) analysis. Pulmonary embolism was diagnosed in 27 referred patients (24%). The sensitivity and specificity of VQS and CTPA were similar to that reported from the literature. A normal VQ scan had the highest negative predictive value (100%), while a high-probability VQ scan had the highest positive predictive value (92%). There was no overall difference (area under the ROC curve (AUC)) between VQS (AUC (95% CI) = 0.82 (0.75,0.89)) and CTPA (AUC = 0.88 (0.81,0.94)) for the diagnosis of PE. Among patients with abnormal chest X-rays, CTPA (AUC 0.90 (0.83,0.97)) appeared somewhat better than VQS (AUC 0.78 (0.68,0.88)) but this difference did not reach statistical significance. In this instance, CTPA is at least as accurate as VQS and may provide an opportunity to make alternative diagnoses. 相似文献
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David C. Klonoff Jordan C. Messler Guillermo E. Umpierrez Limin Peng Robby Booth Jennifer Crowe Valerie Garrett Raymie McFarland Francisco J. Pasquel 《Diabetes care》2021,44(2):578
OBJECTIVEDiabetes and hyperglycemia are important risk factors for poor outcomes in hospitalized patients with coronavirus disease 2019 (COVID-19). We hypothesized that achieving glycemic control soon after admission, in both intensive care unit (ICU) and non-ICU settings, could affect outcomes in patients with COVID-19.RESEARCH DESIGN AND METHODSWe analyzed pooled data from the Glytec national database including 1,544 patients with COVID-19 from 91 hospitals in 12 states. Patients were stratified according to achieved mean glucose category in mg/dL (≤7.77, 7.83–10, 10.1–13.88, and >13.88 mmol/L; ≤140, 141–180, 181–250, and >250 mg/dL) during days 2–3 in non-ICU patients or on day 2 in ICU patients. We conducted a survival analysis to determine the association between glucose category and hospital mortality.RESULTSOverall, 18.1% (279/1,544) of patients died in the hospital. In non-ICU patients, severe hyperglycemia (blood glucose [BG] >13.88 mmol/L [250 mg/dL]) on days 2–3 was independently associated with high mortality (adjusted hazard ratio [HR] 7.17; 95% CI 2.62–19.62) compared with patients with BG <7.77 mmol/L (140 mg/dL). This relationship was not significant for admission glucose (HR 1.465; 95% CI 0.683–3.143). In patients admitted directly to the ICU, severe hyperglycemia on admission was associated with increased mortality (adjusted HR 3.14; 95% CI 1.44–6.88). This relationship was not significant on day 2 (HR 1.40; 95% CI 0.53–3.69). Hypoglycemia (BG <70 mg/dL) was also associated with increased mortality (odds ratio 2.2; 95% CI 1.35–3.60).CONCLUSIONSBoth hyperglycemia and hypoglycemia were associated with poor outcomes in patients with COVID-19. Admission glucose was a strong predictor of death among patients directly admitted to the ICU. Severe hyperglycemia after admission was a strong predictor of death among non-ICU patients. 相似文献
84.
Frances K. Walsh Vivian H. Heyward Candace Garrett Schau 《The Physician and sportsmedicine》2013,41(11):74-89
In brief: The body composition of 49 female intercollegiate basketball players was used to derive a sport-specific equation and to assess the applicability of the Sloan et al (population-specific) and Jackson et al (generalized) equations for use with this sample. The sport-specific equation yielded an adjusted multiple regression of.71 and a standard error of the estimate (SEE) of.0077. A comparative analysis indicated that mean body density was significantly underestimated by 0.0112 gmml?1 using the Sloan and by 0.0126 gmml?1 using the Jackson equations. The SEEs for the Sloan (.0073 gmml?1) and Jackson (.0085 gm ml?1) equations were low; however, each equation produced a large total error (.014 and.016 gmml?1). 相似文献
85.
Yan Ma PhD Garrett G. Sullivan MD Elizabeth Schrick RN In-Young Choi PhD Zhuoya He PhD JoAnn Lierman RN PhD 《Journal of the American College of Nutrition》2013,32(3):187-193
Objective: A simple method of using fingerstick blood glucose (FSBG) monitors to estimate blood ascorbate values after high-dose intravenous (IV) ascorbate infusion is evaluated as a substitution for high-performance liquid chromatography (HPLC) measurement. Methods: In 33 participants, readings from FSBG monitors were taken before and after IV ascorbate infusions at various time points, with the postinfusion FSBG readings subtracted from the baseline glucose readings. The results of the subtractions (AAFSBG) were correlated with ascorbate concentrations detected by HPLC (AAHPLC). Results: A linear regression was found between ascorbate concentrations detected by the fingerstick method (AAFSBG) and by HPLC (AAHPLC). The linear correlations were identical in healthy subjects, diabetic subjects, and cancer patients. Analysis of variance obtained an AAFSBG/AAHPLC ratio of 0.90, with a 90% confidence interval of (0.69, 1.20). The corrections of AAFSBG improved similarity to AAHPLC but did not significantly differ from the uncorrected values. Conclusion: The FSBG method can be used as an approximate estimation of high blood ascorbate concentration after IV ascorbate (>50 mg/dL, or 2.8 mM) without correction. However, this measurement is not accurate in detecting lower or baseline blood ascorbate. It is also important to highlight that in regard to glucose monitoring, FSBG readings will be erroneously elevated following IV ascorbate use and insulin should not be administered to patients based on these readings. 相似文献
86.
This paper describes a project to establish and evaluate online study partnerships, using social networking applications, between final year Canadian nursing students at the University of British Columbia (UBC) and second year undergraduate science education students at the University of Plymouth (UoP) in the UK. The project took place between 2009 and 2010 and evaluated the use of social networking applications with international interdisciplinary partnerships between Canadian and UK students. A multi-method evaluation strategy incorporating questionnaires, online focus groups and web analytics was used to explore the value of social media to promote the exchange of ideas and discussion of scientific philosophy in different contexts, between students working in disciplines with differing philosophical perspectives principally modern/post-modern, quantitative/qualitative, empirical/theoretical. This project resulted in a very successful collaborative partnership between UK and Canadian students. 相似文献
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Effect of prosthetic restoration on masticatory function in patients with shortened dental arches: a multicentre study
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K. Fueki Y. Igarashi Y. Maeda K. Baba K. Koyano K. Sasaki Y. Akagawa T. Kuboki S. Kasugai N. R. Garrett 《Journal of oral rehabilitation》2016,43(7):534-542
The aim of this multicentre study was to investigate the effect of prosthetic restoration for missing posterior teeth on mastication in patients with shortened dental arches (SDAs). Partially dentate patients who had an intact teeth in anterior region and missed distal molar(s) (2–12 missing occlusal units) classified as Kennedy Class I or Class II were recruited from seven university‐based dental hospitals in Japan. Of the 125 subjects who underwent baseline (pre‐treatment) and follow‐up/post‐treatment evaluation, 53 chose no replacement of missing teeth and 72 chose treatment with removable partial dentures (n = 53) or implant‐supported fixed partial dentures (n = 19). Objective masticatory performance (MP) was evaluated using a gummy jelly test. Perception of chewing ability (CA) was rated using a food intake questionnaire. In the no‐treatment group, mean MP and CA scores at baseline were similar to those at follow‐up evaluation (P > 0·05). In the treatment group, mean MP after treatment was significantly greater than the pre‐treatment mean MP (P < 0·05). However, the mean perceived CA in the treatment groups was similar at pre‐ and post‐treatment (P > 0·05). In a subgroup analysis of subjects in the treatment group, subjects with lower pre‐treatment CA showed a significant CA increase after treatment (P = 0·004), but those with higher pre‐treatment CA showed a significant decrease in CA (P = 0·001). These results suggest that prosthetic restoration for SDAs may benefit objective masticatory performance in patients needing replacement of missing posterior teeth, but the benefit in subjective chewing ability seems to be limited in subjects with perceived impairment in chewing ability before treatment. 相似文献
89.
90.
David Neilsen Luis Lehner Carlos Palenzuela Eric W. Hirschmann Steven L. Liebling Patrick M. Motl Travis Garrett 《Proceedings of the National Academy of Sciences of the United States of America》2011,108(31):12641-12646
The extraction of rotational energy from a spinning black hole via the Blandford–Znajek mechanism has long been understood as an important component in models to explain energetic jets from compact astrophysical sources. Here we show more generally that the kinetic energy of the black hole, both rotational and translational, can be tapped, thereby producing even more luminous jets powered by the interaction of the black hole with its surrounding plasma. We study the resulting Poynting jet that arises from single boosted black holes and binary black hole systems. In the latter case, we find that increasing the orbital angular momenta of the system and/or the spins of the individual black holes results in an enhanced Poynting flux. 相似文献