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991.
Sidiropoulos K Glotsos D Kostopoulos S Ravazoula P Kalatzis I Cavouras D Stonham J 《Computers in biology and medicine》2012,42(4):376-386
In the present study a new strategy is introduced for designing and developing of an efficient dynamic Decision Support System (DSS) for supporting rare cancers decision making. The proposed DSS operates on a Graphics Processing Unit (GPU) and it is capable of adjusting its design in real time based on user-defined clinical questions in contrast to standard CPU implementations that are limited by processing and memory constrains. The core of the proposed DSS was a Probabilistic Neural Network classifier and was evaluated on 140 rare brain cancer cases, regarding its ability to predict tumors' malignancy, using a panel of 20 morphological and textural features Generalization was estimated using an external 10-fold cross-validation. The proposed GPU-based DSS achieved significantly higher training speed, outperforming the CPU-based system by a factor that ranged from 267 to 288 times. System design was optimized using a combination of 4 textural and morphological features with 78.6% overall accuracy, whereas system generalization was 73.8%±3.2%. By exploiting the inherently parallel architecture of a consumer level GPU, the proposed approach enables real time, optimal design of a DSS for any user-defined clinical question for improving diagnostic assessments, prognostic relevance and concordance rates for rare cancers in clinical practice. 相似文献
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Hatzimanolis A Smyrnis N Avramopoulos D Stefanis CN Evdokimidis I Stefanis NC 《Psychiatric genetics》2012,22(4):210-213
Independent genome-wide association studies have implicated a common single nucleotide polymorphism within the ANK3 gene (rs10994336) in bipolar disorder (BD) susceptibility, thus establishing rs10994336 marker as a strong candidate predisposing genetic factor for BD. Furthermore, recent findings demonstrate that this variant impacts on cognitive functioning in BD patients, their unaffected relatives, and healthy controls by influencing sustained attention. Here, we aimed to replicate this finding in a large population-based sample of healthy young adults (n=1808). Sustained attention was evaluated using the Continuous Performance Test as in the original study and working memory was assessed with the n-back task. Individuals carrying the BD risk T-allele showed significantly reduced sensitivity in target detection, increased errors of commission, and atypical response latency variability. In addition, we confirmed the lack of an association between the rs10994336 variant and working memory, as well as general intellectual ability, suggesting a specific effect on the Continuous Performance Test performance. 相似文献
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Roda C Kousignian I Guihenneuc-Jouyaux C Dassonville C Nicolis I Just J Momas I 《Environmental health perspectives》2011,119(11):1653-1658
Background: Certain chemical pollutants can exacerbate lower respiratory tract infections (LRIs), a common childhood ailment. Although formaldehyde (FA) is one of the most common air pollutants found in indoor environments, its impact on infant health is uncertain.Objective: Our aim was to determine the impact of FA exposure on the LRI incidence during the first year of life of infants from the Pollution and Asthma Risk: an Infant Study (PARIS) birth cohort.Methods: FA was measured in a random sample of 196 infants’ dwellings, and exposure to this pollutant was estimated for 2,940 infants using predictive models based on measurements and data about potential determinants of FA levels. Health data were collected from parents by regular self-administered questionnaires. We used multivariate logistic regressions to estimate associations between FA exposure and the occurrence of LRI and wheezy LRI (wLRI), adjusting for potential confounders/risk factors.Results: During the first year of life, 45.8% of infants had at least one LRI, and LRI occurred simultaneously with wheezing in 48.7% of cases. The FA predictive models correctly classified 70% of dwellings as having high or low exposure, and we estimated that 43.3% of infants were exposed throughout the first year to levels of FA > 19.5 µg/m3. FA exposure was significantly associated with LRI and wLRI before and after adjustment for known LRI risk factors/confounders. For an interquartile increase in FA levels (12.4 μg/m3), we estimated a 32% [95% confidence interval (CI): 11, 55] and 41% (95% CI: 14, 74) increase in the incidence of LRI and wLRI, respectively.Conclusion: The findings of this study suggest that infants exposed to FA at an early age have an increased incidence of LRI. 相似文献
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Dimopoulou I Nikitas N Orfanos SE Theodorakopoulou M Vassiliadi D Ilias I Ikonomidis I Boutati E Maratou E Tsangaris I Karkouli G Tsafou E Diamantakis A Kopterides P Maniatis N Kotanidou A Armaganidis A Ungerstedt U 《Shock (Augusta, Ga.)》2011,35(4):343-348
Microdialysis (MD) provides the opportunity to monitor tissue metabolic changes. This study aimed to describe the kinetics of MD-derived metabolites during the course of critical sepsis, to assess whether these metabolites are useful in grading sepsis severity, and to investigate their prognostic use. To this end, 54 mechanically ventilated septic patients were prospectively studied, out of which 39 had shock. Upon sepsis onset, an MD catheter was inserted into the subcutaneous adipose tissue of the upper thigh. Dialysate samples were analyzed for glucose, pyruvate, lactate, and glycerol. Sampling was performed six times per day for a maximum of 6 days. The daily mean values of MD measurements were calculated for each patient. Arterial blood was analyzed for glucose, lactate, and glycerol concomitantly with dialysate sampling. Blood glucose and tissue glucose levels along with lactate levels were high during the entire study period. Tissue pyruvate and glycerol were also raised, whereas the lactate-pyruvate ratio was preserved. At study entry, patients with septic shock had higher tissue lactate (3.3 vs. 1.9 mmol/L, P = 0.01) and glycerol (340 vs. 169 μmol/L, P = 0.04) levels compared with those without shock. Nonsurvivors had higher tissue lactate (P = 0.008), glycerol (P = 0.004), and pyruvate (P = 0.002) levels than survivors during the whole observation period. Logistic regression analysis showed that age (odds ratio [OR], 1.075; 95% confidence interval [CI], 1.004-1.150; P = 0.03), Sequential Organ Failure Assessment score on day 1 (OR, 1.550; 95% CI, 1.043-2.312; P = 0.03), and tissue glycerol on day 1 (OR, 1.007; 95% CI, 1.001-1.012; P = 0.01) predicted mortality independently. In conclusion, critical sepsis is characterized by high tissue lactate and pyruvate levels and a preserved lactate-pyruvate ratio, suggesting a nonischemic mechanism for raised blood lactate levels. Septic shock is associated with higher tissue lactate and glycerol levels compared with sepsis without shock. Elevated tissue lactate, pyruvate, and glycerol levels are related to poor clinical outcome, with the latter constituting an independent predictor. 相似文献
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