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51.
The non‐surgical diagnosis of endometriosis is still challenging for the clinician. Ultrasonography and magnetic resonance imaging can be used to diagnose ovarian endometriotic cysts and deep infiltrating endometriosis; but their performance is poor in the diagnosis of initial stages of endometriosis. CA‐125 and other serum markers (such as CA 19‐9, serum protein PP14, interleukins, and angiogenetic factors) have been measured in women with endometriosis but they are not reliable for the diagnosis of the disease. Although several studies used proteomics technologies to identify plasmatic markers of endometriosis, the non‐invasive diagnosis of endometriosis is far from being achieved. In this issue, Manousopoulou et al. compare the integrated quantitative proteomic profile of eutopic endometrium and serum of women with endometriosis and controls. 1214 proteins are differentially expressed in the eutopic endometrium and 404 proteins in the serum of the two study groups. 21 proteins are aberrantly expressed in both eutopic endometrium and serum of women with endometriosis. More work is needed to assess if the differentially expressed proteins identified in this study can be used as clinical markers of endometriosis.  相似文献   
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The EBBTF (European Breeding Blanket Test Facility) experimental plant is a key component for the development of the breeding blankets (TBMs test blanket modules, HCLL helium cooled lithium lead and HCPB helium cooled pebble bed types) used by ITER. EBBTF is an experimental plant which provides the double breeding/cooling loops (liquid metal and gas) required for HCLL testing. EBBTF is composed of four subsystems (TBM, IELLLO integrated European lead lithium loop, HE-FUS3 helium fusion loop, version 3 and helium compressor build by ATEKO) with dedicated control systems realized with hardware/software combinations covering 15 years (1995–2010) time span. At the end of 2010 we began to upgrade the HE-FUS3 data acquisition control systems (DACS) replacing the obsolete PLC Siemens S5 with National Instruments Compact FieldPoint and LabVIEW. The control room has been completely reorganized using high resolution monitors and workstations linked with standard Ethernet interfaces. The data acquisition, control, safety and SCADA software has been completely developed in ENEA using LabVIEW. In this paper we are going to discuss the technical difficulties and the solutions that we have used to accomplish the upgrade.  相似文献   
53.
A thorough analysis of the behavior of error‐correcting codes over space links affected by solar scintillation is presented. The relevant channel parameters are fixed through the development of a model based on real missions' data. Both telecommand and telemetry links are considered in fast and slow fading conditions. Besides classical coherent modulation schemes, the possibility to use noncoherent modulation schemes is considered, to eliminate the problem of phase tracking. For the case of channels with very slow fading, the use of external interleavers or erasure coding is proposed to cope with error bursts.  相似文献   
54.
In diabetes, the mean square error (MSE) metric is extensively used for assessing glucose prediction methods and identifying glucose models. One limitation of this metric is that, by equally treating errors in hypo-, eu-, and hyperglycemia, it is not able to weight the different clinical impact of errors in these three situations. In this paper, we propose a new cost function, which overcomes this limitation and can be used in place of MSE for several scopes, in particular for assessing the quality of glucose predictors and identifying glucose models. The new metric called glucose-specific MSE (gMSE) modifies MSE with a Clark error grid inspired penalty function, which penalizes overestimation in hypoglycemia and underestimation in hyperglycemia, i.e., the most harmful conditions on a clinical perspective. From a mathematical point of view, gMSE retains sensitivity of MSE and inherits some of its important mathematical features, in particular it has no local minima, simplifying the optimization. This makes it suitable for model identification purposes also. First, the goodness of it is demonstrated by means of three experiments, designed ad hoc to evidence its sensitivity to accuracy, precision, and distortion in glucose predictions. Second, a prediction assessment problem is presented, in which two real prediction profiles are compared. Results show that the MSE chooses the worst clinical situation, while gMSE correctly selects the situation with less clinical risk. Finally, we also demonstrate that models identified minimizing gMSE are more accurate in potentially harmful situations (hypo- and hyperglycemia) than those obtained by MSE.  相似文献   
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In this study, regional diastolic patterns and their relations with transmitral Doppler inflow were investigated in hypertrophic cardiomyopathy (HC) by pulsed Doppler tissue imaging (DTI). Doppler echocardiography and DTI of basal septum and lateral wall (apical 4-chamber view) were performed in 20 patients (15 men and 5 women) with HC and in 10 healthy subjects (7 men and 3 women). Diabetes, hypertension, coronary artery and valvular disease, mitral regurgitation, New York Heart Association functional classes III to IV, sinus tachycardia, atrial fibrillation, and inadequate echocardiograms were exclusion criteria. Peak velocity and time-velocity integral of early and late waves and their ratios, and deceleration and isovolumic relaxation times were determined by standard Doppler and by DTI at the septal and lateral wall levels. The 2 groups were comparable for age, heart rate, blood pressure, and ejection fraction. Transmitral peak velocity and time-velocity integral E/A ratios were reduced (both p <0.05) and deceleration and isovolumic relaxation times prolonged (both p <0.00001) in HC. Septal DTI showed lower peak velocity and time-velocity integral e/a ratios (p <0.00001 and p <0.001, respectively) and lengthened regional deceleration (p <0.01) and isovolumic (p <0.001) relaxation times. DTI of the lateral wall showed a prolongation of deceleration and isovolumic relaxation times (both p <0.01). By dividing HC according to transmitral E/A, 8 patients with E/A <1 had lower DTI septal e/a ratio (p <0.01) and prolonged septal deceleration and isovolumic relaxation times (both p <0.01) but no changes in DTI pattern of lateral wall than 12 patients with E/A > 1. In conclusion, DTI is useful and complementary to standard Doppler imaging to characterize diastolic properties in HC, reflecting a typical pattern of intramyocardial impaired relaxation at the level of hypertrophied septum and also providing information about the degree of this regional impairment. The lateral wall presents minor changes in diastolic times, which indicate how diastolic asynchrony is not confined to the hypertrophied segment in HC.  相似文献   
57.
The purpose of this study was to evaluate the association between four distinct histopathological features: (1) tumor infiltrating lymphocytes, (2) mucinous differentiation, (3) tumor-stroma ratio, plus (4) tumor budding and two gene expression-based classifiers—(1) consensus molecular subtypes (CMS) plus (2) colorectal cancer intrinsic subtypes (CRIS). All four histopathological features were retrospectively scored on hematoxylin and eosin sections of the most invasive part of the primary tumor in 218 stage II and III colon cancer patients from two independent cohorts (AMC-AJCC-90 and AC-ICAM). RNA-based CMS and CRIS assignments were independently obtained for all patients. Contingency tables were constructed and a χ2 test was used to test for statistical significance. Odds ratios with 95% confidence intervals were calculated. The presence of tumor infiltrating lymphocytes and a mucinous phenotype (>50% mucinous surface area) were strongly correlated with CMS1 (p < 0.001 and p = 0.008) and CRIS-A (p = 0.006 and p < 0.001). The presence of mucus (≥ 10%) was associated with CMS3: mucus was present in 64.1% of all CMS3 tumors (p < 0.001). Although a clear association between tumor-stroma ratio and CMS4 was established in this study (p = 0.006), still 32 out of 61 (52.5%) CMS4 tumors were scored as stroma-low, indicating that CMS4 tumors cannot be identified solely based on stromal content. Higher budding counts were seen in CMS4 and CRIS-B tumors (p = 0.045 and p = 0.046). No other associations of the measured parameters were seen for any of the other CRIS subtypes. Our analysis revealed clear associations between histopathologic features and CMS or CRIS subtypes. However, identification of distinct molecular subtypes solely based on histopathology proved to be infeasible. Combining both molecular and morphologic features could potentially improve patient stratification.  相似文献   
58.
The identification of advanced fibrosis by applying noninvasive tests is still a key component of the diagnostic algorithm of NAFLD. The aim of this study is to assess the concordance between the FIB-4 and liver stiffness measurement (LSM) in patients referred to two liver centers for the ultrasound-based diagnosis of NAFLD. Fibrosis 4 Index for Liver Fibrosis (FIB-4) and LSM were assessed in 1338 patients. A total of 428 (32%) had an LSM ≥ 8 kPa, whereas 699 (52%) and 113 (9%) patients had an FIB-4 < 1.3 and >3.25, respectively. Among 699 patients with an FIB-4 < 1.3, 118 (17%) had an LSM ≥ 8 kPa (false-negative FIB-4). This proportion was higher in patients ≥60 years, with diabetes mellitus (DM), arterial hypertension or a body mass index (BMI) ≥ 27 kg/m2. In multiple adjusted models, age ≥ 60 years (odds ratio (OR) = 1.96, 95% confidence interval (CI) 1.19–3.23)), DM (OR = 2.59, 95% CI 1.63–4.13), body mass index (BMI) ≥ 27 kg/m2 (OR = 2.17, 95% CI 1.33–3.56) and gamma-glutamyltransferase ≥ 25 UI/L (OR = 2.68, 95% CI 1.49–4.84) were associated with false-negative FIB-4. The proportion of false-negative FIB-4 was 6% in patients with none or one of these risk factors and increased to 16, 31 and 46% among those with two, three and four concomitant risk factors, respectively. FIB-4 is suboptimal to identify patients to refer to liver centers, because about one-fifth may be false negative at FIB-4, having instead an LSM ≥ 8 KPa.  相似文献   
59.
Hollow‐fiber ultrafiltration (UF) membranes were prepared from blends of poly(vinyl chloride) (PVC) and polystyrene (PS) with a dry/wet phase inversion method. Poly(ethylene glycol) (PEG) and N,N‐dimethylacetamide were used as the additive and solvent, respectively. The effects of the PEG concentration in the dope solution as an additive on the cross sections and inner and outer surface morphologies, permeability, and separation performance of the hollow fibers were examined. The mean pore size, pore size distribution, and mean roughness of both the inner and outer surfaces of the produced hollow fibers were determined by atomic force microscopy. Also, the mechanical properties of the hollow‐fiber membranes were investigated. UF experiments were conducted with aqueous solutions of poly(vinyl pyrrolidone) (PVP; K‐90, Mw = 360 kDa). From the results, we found that the PVC/PS hollow‐fiber membranes had two layers with a fingerlike structure. These two layers were changed from a wide and long to a thin and short morphology with increasing PEG concentration. A novel and until now undescribed shape of the nodules in the outer surfaces, which was denoted as a sea‐waves shape, was observed. The outer and inner pore sizes both increased with increasing PEG concentration. The water permeation flux of the hollow fibers increased from 104 to 367 L m?2 h?1 bar?1) at higher PEG concentrations. The PVP rejection reached the highest value at a PEG concentration of 4 wt %, whereas at higher values (from 4 to 9 wt %), the rejection decreased. The same trend was found also for the tensile stress at break, Young's modulus, and elongation at break of the hollow fibers. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 989‐1004, 2013  相似文献   
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