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61.
Karadimas EJ Nicolson T Kakagia DD Matthews SJ Richards PJ Giannoudis PV 《International orthopaedics》2011,35(9):1381-1390
Purpose
The purpose of this study was to evaluate the relation between pelvic fracture patterns and the angiographic findings, and to assess the effectiveness of the embolisation. 相似文献62.
Nicholas V. Sarlis Efthimios S. Skordas Panayiotis A. Varotsos Toshiyasu Nagao Masashi Kamogawa Seiya Uyeda 《Proceedings of the National Academy of Sciences of the United States of America》2015,112(4):986-989
Using the Japan Meteorological Agency earthquake catalog, we investigate the seismicity variations before major earthquakes in the Japanese region. We apply natural time, the new time frame, for calculating the fluctuations, termed β, of a certain parameter of seismicity, termed κ1. In an earlier study, we found that β calculated for the entire Japanese region showed a minimum a few months before the shallow major earthquakes (magnitude larger than 7.6) that occurred in the region during the period from 1 January 1984 to 11 March 2011. In this study, by dividing the Japanese region into small areas, we carry out the β calculation on them. It was found that some small areas show β minimum almost simultaneously with the large area and such small areas clustered within a few hundred kilometers from the actual epicenter of the related main shocks. These results suggest that the present approach may help estimation of the epicentral location of forthcoming major earthquakes.In this study, we investigate the evolution of seismicity shortly before main shocks in the Japanese region, , using Japan Meteorological Agency (JMA) earthquake catalog as in ref 1. For this, we adopted the new time frame called natural time since our previous works using this time frame made the lead time of prediction as short as a few days (see below). For a time series comprising N earthquakes (EQs), the natural time χk is defined as χk = k/N, where k means the kth EQ with energy Qk (Fig. 1). Thus, the raw data for our investigation, to be read from the earthquake catalog, are χk = k/N and , where pk is the normalized energy. In natural time, we are interested in the order and energy of events but not in the time intervals between events.Open in a separate windowFig. 1.EQ sequence in (A) conventional time and (B) natural time. In B, Qk is given in units of the energy ε corresponding to a 3.5MJMA EQ.We first calculate a parameter called κ1, which is defined as follows (2, 3), from the catalog.[1]We start the calculation of κ1 at the time of initiation of Seismic Electric Signals (SES), the transient changes of the electric field of Earth that have long been successfully used for short-term EQ prediction (4, 5). The area to suffer a main shock is estimated on the basis of the selectivity map (4, 5) of the station that recorded the corresponding SES. Thus, we now have an area in which we count the small EQs of magnitude greater than or equal to a certain magnitude threshold that occur after the initiation of the SES. We then form time series of seismic events in natural time for this area each time a small EQ occurs, in other words, when the number of the events increases by one. The κ1 value for each time series is computed for the pairs (χk,pk) by considering that χk is “rescaled” to χk = k/(N +1) together with rescaling upon the occurrence of any additional event in the area. The resulting number of thus computed κ1 values is usually of the order 102 to 103 depending, of course, on the magnitude threshold adopted for the events that occurred after the SES initiation until the main shock occurrence. When we followed this procedure, it was found empirically that the values of κ1 converge to 0.07 a few days before main shocks. Thus, by using the date of convergence to 0.07 for prediction, the lead times, which were a few months to a few weeks or so by SES data alone, were made, although empirically, as short as a few days (6, 7). In fact, the prominent seismic swarm activity in 2000 in the Izu Island region, Japan, was preceded by a pronounced SES activity 2 mo before it, and the approach of κ1 to 0.07 was found a few days before the swarm onset (8). However, when SES data are not available, which is usually the case, it is not possible to follow the above procedure. To cope with this difficulty, in the previous work (1), we investigated the time change of the fluctuation of the κ1 values during a few preseismic months for each EQ (which we call target EQ) over the large area (Fig. 2A) for the period from 1 January 1984 to 11 March 2011, the day of M9.0 Tohoku EQ. Setting a threshold MJMA = 3.5 to assure data completeness of JMA catalog, we were left with 47,204 EQs in the concerned period of about 326 mo: ∼150 EQs per month. For calculating the β values, we chose 200 EQs before target EQs to cover the seismicity in almost one and a half months.Open in a separate windowFig. 2.(A) The 47,204 EQs with MJMA ≥ 3.5 that occurred during the period of our study. (B) Contours of the number of EQs per month within R = 250 km. Solid diamonds show the epicenters of six shallow EQs investigated in this study. (C) Contours of the natural time window W used in each of the 12,476 areas of radius R = 250 km with offset 0.1° from one another that have at least eight EQs per month.To obtain the fluctuation β of κ1, we need many values of κ1 for each target EQ. For this purpose, we first took an excerpt comprised of W successive EQs just before a target EQ from the seismic catalog. The number W was chosen to cover a period of a few months. For this excerpt, we form its subexcerpts of consecutive N = 6 EQs (since at least six EQs are needed (2) for obtaining reliable κ1) of energy Qj+k?1 and natural time χk = k/N each. Further, , and by sliding Sj over the excerpt of W EQs, (= W − 5), we calculate κ1 using Eq. 1 for each j. We repeat this calculation for , thus obtaining an ensemble of [(W − 4)(W − 5)]/2 (= 1 + 2 +…+ W − 5) κ1 values. Then, we compute the average μ(κ1) and the SD σ(κ1) of thus obtained ensemble of [(W − 4)(W − 5)]/2 κ1 values. The variability β of κ1 for this excerpt W is defined to be β ≡ σ(κ1)/μ(κ1) and is assigned to the (W + 1)th EQ, i.e., the target EQ.The time evolution of the β value can be pursued by sliding the excerpt through the EQ catalog. Namely, through the same process as above, β values assigned to (W + 2)th, (W + 3)th, … EQs in the catalog can be obtained.We found in ref. 1 that the fluctuation β of κ1 values exhibited minimum a few months before all of the six shallow EQs of magnitude larger than 7.6 that occurred in the study period. A minimum of β ≡ σ(κ1)/μ(κ1) means large average and/or small deviation of κ1 values (e.g., see ref. 9).In the present work, we calculate the β values for small areas before the six large EQs, which showed β minima of the large area. 相似文献
63.
Michael I. Koukourakis Christos Kakouratos Dimitra Kalamida Zoi Bampali Sophia Mavropoulou Efthimios Sivridis 《International journal of radiation biology》2016,92(7):353-363
Purpose: To assess whether anaerobic metabolism, proliferation activity and stem cell content are linked with radioresistance in bladder cancer. Materials and methods: Tissue sections from 66 patients with invasive transitional cell bladder cancer treated with hypofractionated accelerated radiotherapy, was immunohistochemically analyzed for the Hypoxia-Inducible Factor 1α (HIF1α) and the anaerobic glycolysis enzyme lactate dehydrogenase 5 (LDH5). Proliferation index (Ki-67) and stem-cell marker (cluster of differentiation CD44, aldehyde dehydrogenase ALDH1) expression was also examined. Results: Both HIF1α and LDH5 expression were linked with high CD44 stem cell population (p?=?0.001 and 0.05, respectively), while high Ki-67 proliferation index was linked with nuclear LDH5 expression (p?=?0.03) and high histological grade (p?=?0.02). A strong significant association of HIF1α (p?=?0.0009) and of LDH5 (p?0.0001) with poor local relapse free survival (LRFS) was noted, which was also confirmed in multivariate analysis. A significant association with overall survival was also noted. Silencing of lactate dehydrogenase LDHA gene in the human RT112 bladder cancer cell line, or exposure to oxamate (LDH activity inhibitor), resulted in strong radio-sensitization. Conclusions: HIF1α and LDH5 are markers of poor outcome in patients with bladder cancer treated with radiotherapy. Blockage of anaerobic metabolism may prove of importance in clinical radiotherapy. 相似文献
64.
A Giatromanolaki M I Koukourakis E Sivridis K O'Byrne G Cox P E Thorpe K C Gatter A L Harris 《Clinical cancer research》2000,6(5):1917-1921
We investigated the expression of MUC1 protein and its relationship to the microvessel density and the expression of thymidine phosphorylase, vascular endothelial growth factor (VEGF), VEGF-receptor KDR, basic fibroblast growth factor (bFGF), and bFGF-receptor (FGFR-2) in non-small cell lung cancer. Although MUC1 expression was found equally in poorly and highly vascularized tumors, a significant coexpression with multiple angiogenic factors and their receptors was noted (P = 0.0002, 0.03, 0.19, 0.10, and 0.01 for thymidine phosphorylase, VEGF, KDR, bFGF, and FGFR-2, respectively). In multiple regression analysis, both angiogenesis and MUC1 expression were independent prognostic variables. The present study suggests the existence of an early genetic event leading to the activation of both migration and angiogenesis pathways in non-small cell lung cancer. 相似文献
65.
66.
Sotirios G. Tsiogkas Maria G. Grammatikopoulou Konstantinos Gkiouras Efterpi Zafiriou Iordanis Papadopoulos Christos Liaskos Efthimios Dardiotis Lazaros I. Sakkas Dimitrios P. Bogdanos 《Nutrients》2021,13(12)
Rheumatic diseases (RDs) are often complicated by chronic symptoms and frequent side-effects associated with their treatment. Saffron, a spice derived from the Crocus sativus L. flower, is a popular complementary and alternative medicine among patients with RDs. The present systematic review aimed to summarize the available evidence regarding the efficacy of supplementation with saffron on disease outcomes and comorbidities in patients with RD diagnoses. PubMed, CENTRAL, clinicaltrials.gov and the grey literature were searched until October 2021, and relevant randomized controlled trials (RCTs) were screened for eligibility using Rayyan. Risk of bias was assessed using the Cochrane’s Risk of Bias-2.0 (RoB) tool. A synthesis without meta-analysis (SWiM) was performed by vote counting and an effect direction plot was created. Out of 125 reports, seven fulfilled the eligibility criteria belonging to five RCTs and were included in the SWiM. The RCTs involved patients with rheumatoid arthritis, osteoarthritis and fibromyalgia, and evaluated outcomes related to pain, disease activity, depression, immune response, inflammation, oxidative stress, health, fatigue and functional ability. The majority of trials demonstrated some concerns regarding overall bias. Moreover, the majority of trialists failed to adhere to the formula elaborations suggested by the CONSORT statement for RCTs incorporating herbal medicine interventions. Standardization of herbal medicine confirms its identity, purity and quality; however, the majority of trials failed to adhere to these guidelines. Due to the great heterogeneity and the lack of important information regarding the standardization and content of herbal interventions, it appears that the evidence is not enough to secure a direction of effect for any of the examined outcomes. 相似文献
67.
68.
Ioannis Liampas MD MSc Konstantinos S. Mylonas MD PhD PDCP Alexandros Brotis MD PhD Panagiotis Dervenis MD MSc Vasileios Siokas MD PhD Alexios-Fotios A. Mentis MD MPH PgCert Metaxia Dastamani MD MSc Athina-Maria Aloizou MD Zisis Tsouris MD MSc Paraskevi Aslanidou BSc MSc Christos Bakoyiannis MD PhD Efthimios Dardiotis MD PhD 《Headache》2021,61(1):44-59
69.
Adamos-Konstantinos Konstantinou Konstantinos Bonotis Maria Sokratous Vasileios Siokas Efthimios Dardiotis 《Archives of Psychiatric Nursing》2018,32(3):449-456
Background
Job burnout is one of the most serious occupational health hazards, especially, among mental health nurses. It has been attributed among others to staff shortages, health service changes, poor morale and insufficient employee participation in decision-making.Aim
The aim of this study was to measure burnout among mental health nurses, investigate relations between burnout and organizational factors and examine potential predictors of nurses' burnout. Specifically, this study aimed to investigate whether role conflict, role ambiguity, organizational commitment and subsequent job satisfaction could predict each of the three dimensions of burnout.Design/methodology/approach
During current cross sectional, the survey was administered to 232 mental health nurses, employed in four private psychiatric clinics in the region of Larissa, Thessaly, Greece in May 2015. Our findings were based on the responses to 78 usable questionnaires. Different statistical analyses, such as correlation analyses, regression analyses and analyses of variance were performed in order to explore possible relations.Findings
High emotional exhaustion (EE) accounted for 53.8% of the sample, while high depersonalization (DP) and high personal accomplishment (PA) accounted for 24.4% and 25.6%, respectively. The best predictors of burnout were found to be role conflict, satisfaction with workload, satisfaction with training, role ambiguity, satisfaction with pay and presence of serious family issues.Practical implications
These findings have implications for organizational and individual interventions, indicating that mental health nurses' burnout could be reduced, or even prevented by team building strategies, training, application of operation management, clear instructions and psychological support. 相似文献70.
Theodorakis G Katsikis A Livanis E Kostopoulou A Adamopoulos S Tsiapras D Voudris V 《Pacing and clinical electrophysiology : PACE》2011,34(11):1553-1560
Background: We aimed at evaluating the long‐term effects of cardiac resynchronization therapy (CRT) in nonambulatory New York Heart Association (NYHA) IV heart failure patients (NAIVHFP). Methods: Eighteen patients, 15 men and three women, eight with ischemic and 10 with nonischemic cardiomyopathy, who underwent biventricular pacemaker implantation while they were in nonambulatory NYHA IV class, were studied. Patients’ age was 58 ± 9 years and left ventricular ejection fraction (LVEF) 18 ± 3 %. Follow‐up data were obtained through review of follow‐up visits notes, stored echocardiographic studies, device interrogation data, and death certificates. Results: After a mean duration of 1223 ± 846 days, 11 patients were alive, including five patients who underwent heart transplantation (OCT) and seven dead. Three of 11 patients who received a CRT‐defibrillator, experienced at least one appropriate discharge, but eventually they either died or received an OCT during follow‐up. Sustained improvements in NYHA class (Z = 2.4, P = 0.015) and 6‐minute walk distance (0 vs 212 ± 95 m, P ? 0.001) were documented after a median duration of 855 days postimplantation. Cumulative proportion of death or OCT at 18 months—when full follow‐up data were available—was 18%, which compared favorably with historical controls. Full echocardiographic and clinical follow‐up data at 12‐months postimplantation were available for 10 patients, documenting a significant reduction in end‐systolic volume (248 ± 82 vs 269 ± 97 mL, P = 0.039). Conclusions: CRT can be safely applied in this subset of extreme severity heart failure patients, achieving encouraging survival rates and reverse remodeling effects. These observations can form an evidence‐based rationale for including NAIVHFP in randomized CRT trials. (PACE 2011; 34:1553–1560) 相似文献