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981.
Ryszard Piotrowicz Andrzej Dabrowski Wojciech Kwiatkowski 《Annals of noninvasive electrocardiology》1998,3(2):131-138
Background: The diagnostic value of ambulatory ECG monitoring in screening for coronary artery disease has been studied in diverse and usually small groups of patients. There are no studies evaluating the diagnostic value of Holter recorded ST depression using the Bayes' theorem of probability, which accounts for the prevalence of the disease in prespecified populations. Purpose: Applying the Bayes' theorem, this study aimed to examine the diagnostic value of Holterrecorded 1-mm ST depression in patients screened for coronary artery disease (CAD) and to identify groups of patients who may benefit from diagnostic ST segment monitoring in ambulatory ECG recordings. Methods: The ST segment analysis was performed in 24-hour ambulatory ECG monitoring of 460 subjects (375 males; aged 35–65, mean 48.6 years), who were screened for CAD and had coronary angiography. The Bayes' formulae were used to calculate the predictive value of ST segment monitoring (posttest likelihood of CAD) in comparison to pretest likelihood of the disease based on age, gender, and symptoms. Results: The 1-mm ST depression was identified in the ambulatory ECG monitoring in 203 (44%) patients. CAD was angiographically confirmed in 279 (61%) patients. The 1-mm ST depression had 54% sensitivity, 71% specificity, 74% positive predictive value, and 50% negative predictive value for CAD. The Bayes' theorem analysis with adjustment for pretest likelihood of the disease in relation to age, gender, and symptoms showed that 1-mm ST segment depression is significant diagnostically in patients with pretest likelihood of the disease exceeding 75%, i.e., in males aged 35–45 years and females aged 56–65 years, both with typical angina. In other groups of patients regardless of the symptoms, age, and gender, detection of ST segment depression does not improve the diagnostic process. A negative result (absence of ST segment depression) can be helpful, confirming the absence of CAD in patients with 15%–25% pretest likelihood of the disease, i.e., in females aged 35–45 years with atypical angina pains and in males aged 46–55 years with nonanginal chest pains. Conclusions: Based on our observations, the 1-mm ST segment depression detected on 24-hour ambulatory ECG monitoring indicates a high likelihood of CAD in patients with < 75% pretest likelihood of the disease. ST segment analysis in other age and gender relative groups of patients, regardless of the nature of their symptoms, does not significantly improve diagnosis process. 相似文献
982.
Bertrand?Guidet Hans?Flaatten Ariane?Boumendil Alessandro?Morandi Finn?H.?Andersen Antonio?Artigas Guido?Bertolini Maurizio?Cecconi Steffen?Christensen Loredana?Faraldi Jesper?Fj?lner Christian?Jung Brian?Marsh Rui?Moreno Sandra?Oeyen Christina?Agwald??hman Bernardo?Bollen?Pinto Ivo?W.?Soliman Wojciech?Szczeklik Andreas?Valentin Ximena?Watson Tilemachos?Zafeiridis Dylan?W.?De?Lange 《Intensive care medicine》2018,44(7):1027-1038
Purpose
To document and analyse the decision to withhold or withdraw life-sustaining treatment (LST) in a population of very old patients admitted to the ICU.Methods
This prospective study included intensive care patients aged?≥?80 years in 309 ICUs from 21 European countries with 30-day mortality follow-up.Results
LST limitation was identified in 1356/5021 (27.2%) of patients: 15% had a withholding decision and 12.2% a withdrawal decision (including those with a previous withholding decision). Patients with LST limitation were older, more frail, more severely ill and less frequently electively admitted. Patients with withdrawal of LST were more frequently male and had a longer ICU length of stay. The ICU and 30-day mortality were, respectively, 29.1 and 53.1% in the withholding group and 82.2% and 93.1% in the withdrawal group. LST was less frequently limited in eastern and southern European countries than in northern Europe. The patient-independent factors associated with LST limitation were: acute ICU admission (OR 5.77, 95% CI 4.32–7.7), Clinical Frailty Scale (CFS) score (OR 2.08, 95% CI 1.78–2.42), increased age (each 5 years of increase in age had a OR of 1.22 (95% CI 1.12–1.34) and SOFA score [OR of 1.07 (95% CI 1.05–1.09 per point)]. The frequency of LST limitation was higher in countries with high GDP and was lower in religious countries.Conclusions
The most important patient variables associated with the instigation of LST limitation were acute admission, frailty, age, admission SOFA score and country.Trial registration
ClinicalTrials.gov (ID: NTC03134807).983.
984.
Three‐dimensional printed polycaprolactone‐based scaffolds provide an advantageous environment for osteogenic differentiation of human adipose‐derived stem cells 下载免费PDF全文
Sławomir Rumiński Barbara Ostrowska Jakub Jaroszewicz Tomasz Skirecki Krzysztof Włodarski Wojciech Święszkowski Małgorzata Lewandowska‐Szumieł 《Journal of tissue engineering and regenerative medicine》2018,12(1):e473-e485
The capacity of bone grafts to repair critical size defects can be greatly enhanced by the delivery of mesenchymal stem cells (MSCs). Adipose tissue is considered the most effective source of MSCs (ADSCs); however, the efficiency of bone regeneration using undifferentiated ADSCs is low. Therefore, this study proposes scaffolds based on polycaprolactone (PCL), which is widely considered a suitable MSC delivery system, were used as a three‐dimensional (3D) culture environment promoting osteogenic differentiation of ADSCs. PCL scaffolds enriched with 5% tricalcium phosphate (TCP) were used. Human ADSCs were cultured in osteogenic medium both on the scaffolds and in 2D culture. Cell viability and osteogenic differentiation were tested at various time points for 42 days. The expression of RUNX2, collagen I, alkaline phosphatase, osteonectin and osteocalcin, measured by real‐time polymerase chain reaction was significantly upregulated in 3D culture. Production of osteocalcin, a specific marker of terminally differentiated osteoblasts, was significantly higher in 3D cultures than in 2D cultures, as confirmed by western blot and immunostaining, and accompanied by earlier and enhanced mineralization. Subcutaneous implantation into immunodeficient mice was used for in vivo observations. Immunohistological and micro‐computed tomography analysis revealed ADSC survival and activity toward extracellular production after 4 and 12 weeks, although heterotopic osteogenesis was not confirmed – probably resulting from insufficient availability of Ca/P ions. Additionally, TCP did not contribute to the upregulation of differentiation on the scaffolds in culture, and we postulate that the 3D architecture is a critical factor and provides a useful environment for prior‐to‐implantation osteogenic differentiation of ADSCs. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
985.
986.
Ewa Wunsch Michał Post Krzysztof Gutkowski Wojciech Marlicz Barbara Szymanik Marek Hartleb Piotr Milkiewicz 《Digestive and liver disease》2010,42(11):818-821
Background
Recent studies suggest that stage-independent symptoms of primary biliary cirrhosis (PBC) such as chronic fatigue are a consequence of structural and functional abnormalities of the brain. Critical flicker frequency (CFF) is a psychophysiological modality analysing function of cerebral cortex.Aim
To analyse the usefulness of CFF in detection of brain dysfunction in patients with PBC.Methods
Fifty-one (37 non-cirrhotic/14 cirrhotic) patients with PBC were included. Control group consisted of 31 matched healthy individuals. Fatigue and health-related quality of life (HRQoL) were assessed using Fatigue Impact Scale (FIS) and questionnaire PBC-40. CFF was analysed with HEPAtonorm Analyzer®.Results
When compared to healthy controls all patients with PBC showed significantly impaired HRQoL in majority of PBC-40 domains and increased fatigue level in physical domain of FIS. No differences in HRQoL and PBC-40 domains were seen, when patients with and without cirrhosis where compared. CFF analysis showed no difference between healthy controls and patients with PBC. CFF did not correlate with PBC-40 and FIS domains.Conclusion
CFF fails to determine brain dysfunction in non-encephalopatic patients with PBC, suggesting that functional efficiency of their cerebral cortex remains unaffected and other central mechanisms are responsible for chronic fatigue in these patients. 相似文献987.
988.
YiYang Dai Sascha S. Chopra Wojciech M. Wysocki Michael Hünerbein 《International journal of colorectal disease》2010,25(12):1475-1479
Background
The application of stents in benign colorectal strictures is considered controversial. The aim of the present study was to assess effectiveness and complications associated with colorectal stent placement in benign colorectal disease. 相似文献989.