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21.
Muzaffer Kahyaoglu MD Arzu Kalayci MD Cetin Gecmen MD Munevver Sari MD Ahmet Guner MD Mehmet Celik MD Ibrahim Akin İzgi MD Cevat Kirma MD 《Echocardiography (Mount Kisco, N.Y.)》2018,35(2):258-259
A 42‐year‐old female patient was referred our clinic for investigation of a history of acute retinal artery occlusion. Transthoracic echocardiography showed a cyst‐like, mobile formation on posterior mitral valve leaflet. 2D and real time 3D transesophageal echocardiography showed a flexible circular mobile structure which was attached to posterior mitral valve leaflet. Echocardiographic appearance and morphological characteristics were suggestive of accessory mitral valve tissue. 相似文献
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A. Torres F. Lopez Boo V. Parra C. Vazquez S. Segura‐Pérez Z. Cetin R. Pérez‐Escamilla 《Child: care, health and development》2018,44(1):4-11
Background
Chile Crece Contigo (ChCC) is defined as a comprehensive, intersectoral, and multicomponent policy that aims to help all children reach their full potential for development, regardless of their socio‐economic status.Methods
This case study was developed on the basis of grey literature review and key informants' interviews.Results
ChCC behaves as a complex adaptive system that combines universal and targeted benefits for the more vulnerable starting since gestation and until the children are 4 years old. Three key ministries are involved in ChCC management: health, education, and social development. Studies show adequate programme implementation and positive effects of ChCC on child development. In addition, it was found that the more families use ChCC benefits and the longer the subsystem has been operating in the commune, the greater the positive effects.Conclusions
Strong political support based on principles of equity and child rights combined with strong evidence and funding commitment from government has been central to emergence, scaling up, and sustainability of ChCC. Further sustainability of ChCC will rely on firmly establishing a well‐trained and compensated cadre of early child development professionals and paraprofessionals as well as an improved management and evaluation decentralized system. 相似文献25.
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Stereopsis of X-ray images can produce 3D tree of coronary arteries up to a certain accuracy level with a lower dose of radiation when compared to computer tomography (CT). In this study, a novel and complete automatic system is designed that covers preprocessing, segmentation, matching and reconstruction steps for that purpose. First, an automatic and novel pattern recognition technique is applied for extraction of the bifurcation points with their diameters recorded in a map. Then, a novel optimization algorithm is run for matching the branches efficiently which is based on that map and the epipolar geometry of stereopsis. Finally, cut branches are fixed one by one at the bifurcations for completing the 3D reconstruction. This method prevails the similar ones in the literature with this novelty since it automatically and inherently prevents the wrong overlapping of branches. Other essential problems like correct detection of the bifurcations and accurate calibration parameters and fast overlapping of matched branches are addressed at acceptable levels. The accuracy of bifurcation extraction is high at 90 % with 96 % sensitivity. Accuracy of vessel centerlines has rootmean-square (rms) error smaller than 0.57 mm for 20 different patients. For phantom model, rms error is 0.75?±?0.8 mm in 3D localization. 相似文献
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Targeted vessel reconstruction in non‐contrast‐enhanced steady‐state free precession angiography
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Efe Ilicak Suheyla Cetin Elif Bulut Kader Karli Oguz Emine Ulku Saritas Gozde Unal Tolga Çukur 《NMR in biomedicine》2016,29(5):532-544
Image quality in non‐contrast‐enhanced (NCE) angiograms is often limited by scan time constraints. An effective solution is to undersample angiographic acquisitions and to recover vessel images with penalized reconstructions. However, conventional methods leverage penalty terms with uniform spatial weighting, which typically yield insufficient suppression of aliasing interference and suboptimal blood/background contrast. Here we propose a two‐stage strategy where a tractographic segmentation is employed to auto‐extract vasculature maps from undersampled data. These maps are then used to incur spatially adaptive sparsity penalties on vascular and background regions. In vivo steady‐state free precession angiograms were acquired in the hand, lower leg and foot. Compared with regular non‐adaptive compressed sensing (CS) reconstructions (CSlow), the proposed strategy improves blood/background contrast by 71.3 ± 28.9% in the hand (mean ± s.d. across acceleration factors 1–8), 30.6 ± 11.3% in the lower leg and 28.1 ± 7.0% in the foot (signed‐rank test, P < 0.05 at each acceleration). The proposed targeted reconstruction can relax trade‐offs between image contrast, resolution and scan efficiency without compromising vessel depiction. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Increased immunoglobulin E response in acute coronary syndromes 总被引:3,自引:0,他引:3
The role of inflammation and mast cell activation has been implicated in atherosclerotic plaque destabilization and rupture. To investigate the role of immunoglobulin E (IgE) in acute coronary syndrome, a prospective clinical study was conducted in patients with acute myocardial infarction (AMI), unstable angina pectoris (UAP), stable angina pectoris (SAP), and healthy controls. IgE levels were serially measured and compared in consecutive patients with AMI (n = 16) and UAP (n = 14) on days 1, 3, 7, 21 after admission and 3 months later and only once in stable angina pectoris (n = 15) and healthy controls (n = 14). In addition, blood eosinophil and basophil levels on admission were measured in all groups and compared. Initial IgE levels determined at admission in patients with AMI, UAP, and SAP were significantly higher than levels in the control group (p = 0.002). Initial high IgE level in AMI on day 1 increased to a peak by day 7 (p = 0.024), then gradually decreased by day 21 and at 3 months (p = 0.052). High IgE level in UAP persisted by day 7 and gradually decreased by day 21 and 3 months (p = 0.037 and p = 0.018, respectively). Blood eosinophil count on admission was significantly higher in UAP than in the control group (p = 0.005). Basophil levels of both AMI and UAP groups on admission were found to be elevated as opposed to control group (p = 0.02 and p = 0.012, respectively). This study demonstrates that the level of IgE significantly increased during the acute phase of acute coronary syndromes and gradually decreased, supporting the role of acute inflammatory response and mast cell involvement in plaque rupture. 相似文献
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Abaci A Oguzhan A Unal S Kiranatli B Eryol NK Basar E Ergin A Cetin S 《Cardiology》2002,98(1-2):50-59
OBJECTIVES: The vena contracta is the narrowest region of the regurgitant or stenotic jet just downstream the orifice and reflects the size of that orifice. This study was performed to assess the accuracy of the vena contracta width (VCW) in evaluating the severity of mitral stenosis (MS) and to compare the mitral valve area (MVA) determined by VCW with MVAs obtained by other more traditional echocardiographic methods. METHODS: We studied 59 patients (43 females, 42 +/- 14 years) with MS. VCW was measured in the apical four chamber view by Doppler color flow mapping. The largest diameter of the VCW during diastole was measured for at least three cardiac cycles and averaged. MVA was calculated from the following equation: pir(2), where r = VCW/2. MVA was also determined by planimetry, the pressure half-time method, and by the Gorlin formula. RESULTS: In this study, the width of the vena contracta ranged from 0.89 to 1.73 cm (mean 1.30 +/- 0.21). MVA, calculated based on the VCW, ranged from 0.63 to 2.35 cm(2) (mean 1.36 +/- 0.41). MVA by VCW (1.36 +/- 0.41 cm(2)) showed good correlations with three comparative techniques: (1) the cross-sectional area by planimetry (1.35 +/- 0.36 cm(2), mean difference = 0.21 +/- 0.16 cm(2), y = 0.91x + 0.14, r = 0.79, SEE = 0.26 cm(2), p < 0.001); (2) the area derived from the Doppler pressure half-time (1.27 +/- 0.32 cm(2), mean difference = 0.22 +/- 0.19 cm(2), y = 0.97x + 0.13, r = 0.76, SEE = 0.27 cm(2), p < 0.001), and (3) the area derived from the Gorlin equation in the 18 patients who underwent catheterization (1.27 +/- 0.35 cm(2), mean difference = 0.19 +/- 0.16, y = 0.98x + 0.05, r = 0.81, SEE = 0.26 cm(2), p < 0.001). CONCLUSIONS: These findings suggest that Doppler color flow imaging of the MS jet in the vena contracta can provide an accurate estimation of MVA and appears to be potentially applicable in the assessment of the severity of MS. 相似文献