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Although hydatic cyst disease rarely involves myocardium and endocardium, cardiac echinococcosis, a potentially life-threatening condition, should be managed promptly. We report a case of right ventricle hydatid cyst detected after syncopal attack in a pregnant woman by using echocardiography .  相似文献   
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Left ventricular (LV) remodeling is a major determinant of the clinical course and outcome of systolic heart failure (HF). Activation of neurohormonal and inflammatory cytokine pathways and their effects on intracellular signal transduction cascades through stimulation of membrane-bound receptors mediate LV remodeling. Although major advances have been made in clinical management of HF through large randomized trials, its prognosis remains poor. Interindividual differences, often genetically based, are increasingly recognized as important determinants of LV remodeling. Identification of the influence of these individual factors on the clinical course of HF has stimulated a search for specific pathophysiologic mechanisms that operate at the individual level and can be targeted directly. This article summarizes the current application of molecular imaging techniques to the understanding of the cellular and molecular mechanisms involved in LV remodeling in an attempt to provide the tools necessary for personalized, truly “evidence-based” assessment, serial evaluation, and monitoring of HF.  相似文献   
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Renal impairment frequently accompanies heart failure (HF) and is a recognized independent risk factor for morbidity and mortality. Few data are available assessing the impact of worsening renal function (WRF) during hospitalization on health care resource use in patients with HF. Health Insurance Portability and Accountability Act-compliant, de-identified, clinical, laboratory, and economic data for patients admitted to a tertiary care medical center with a primary diagnosis of HF were extracted by MedMining and reviewed retrospectively by the authors. Patients were excluded if they had no previous HF or were admitted for acute coronary syndrome or coronary artery bypass grafting within 30 days of index hospitalization. WRF was defined as ≥ 0.3 mg/dl increase in serum creatinine from baseline at any time during hospitalization. Of 5,803 hospitalized patients with primary HF diagnosis, 827 patients (14%) fulfilled all prespecified inclusion and exclusion criteria (74 ± 14 years of age, 43% men, 98% white, admission serum creatinine 1.4 ± 0.9 mg/dl, estimated glomerular filtration rate < 90 ml/min/1.73 m(2) at admission in 83%). During index hospitalization, WRF was identified in nearly 33%. Compared to patients without WRF, those with WRF had greater prevalence of diabetes (54% vs 43%), lower estimated glomerular filtration rate (44 ± 30 vs 62 ± 35 ml/min/1.73 m(2)), higher serum potassium (4.3 ± 0.7 vs 4.2 ± 0.7 mEq/L), and higher B-type natriuretic peptide (845 ± 821 vs 795 ± 947 pg/ml) at baseline (all p values < 0.05). Patients developing WRF incurred higher total inpatient costs ($10,977, range 671 to 212,819, vs $7,820, range 697 to 269,797, p < 0.001) and longer hospital stay (8.2 ± 6.8 vs 5.7 ± 5.5 days, p < 0.001). In conclusion, occurrence of WRF during HF-related hospitalization is associated with higher hospitalization costs and longer hospital stay.  相似文献   
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Purpose

Quantification of teeth is of clinical importance for various computer assisted procedures such as dental implant, orthodontic planning, face, jaw and cosmetic surgeries. In this regard, segmentation is a major step.

Methods

In this paper, we propose a method for segmentation of teeth in volumetric computed tomography (CT) data using panoramic re-sampling of the dataset in the coronal view and variational level set. The proposed method consists of five steps as follows: first, we extract a mask in a CT images using Otsu thresholding. Second, the teeth are segmented from other bony tissues by utilizing anatomical knowledge of teeth in the jaws. Third, the proposed method is followed by estimating the arc of the upper and lower jaws and panoramic re-sampling of the dataset. Separation of upper and lower jaws and initial segmentation of teeth are performed by employing the horizontal and vertical projections of the panoramic dataset, respectively. Based the above mentioned procedures an initial mask for each tooth is obtained. Finally, we utilize the initial mask of teeth and apply a Variational level set to refine initial teeth boundaries to final contours.

Results

The proposed algorithm was evaluated in the presence of 30 multi-slice CT datasets including 3,600 images. Experimental results reveal the effectiveness of the proposed method.

Conclusion

In the proposed algorithm, the variational level set technique was utilized to trace the contour of the teeth. In view of the fact that, this technique is based on the characteristic of the overall region of the teeth image, it is possible to extract a very smooth and accurate tooth contour using this technique. In the presence of the available datasets, the proposed technique was successful in teeth segmentation compared to previous techniques.  相似文献   
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Respiratory failure that requires endotracheal intubation is an uncommon but potentially fatal complication of scald burns in children. Because scalds are rarely associated with a direct pulmonary injury, the pathophysiology of respiratory failure is unclear. A possible mechanism may be upper airway edema, diminished pulmonary compliance secondary to fluid resuscitation, or both. To identify an at-risk population for intubation after a scald injury, the hospital courses of 174 consecutive patients under the age of 14 years who were admitted after a scald injury to a single burn center during a 6-year period were examined. Seven of these patients (4%) required endotracheal intubation. No patient older than 2.8 years or who had a scald injury that covered less than 19% of the total body surface area required intubation. Patients who required intubation were younger (mean age, 1.4 vs. 2.8 years, P<.001), had a larger mean burn size (29.9% vs. 12.3% total body surface area, P<.001), and required more fluid resuscitation (7.66 vs. 4.07 cc/kg per percentage of total body surface area burned, P<.001) than patients who did not require intubation. Examination of the adequacy of resuscitation revealed that the intubated patients had an average hourly urine output of 0.84 cc/kg during the first 24 hours, suggesting that resuscitation was not excessive. Multivariate analysis demonstrated that both larger burn size (P = .041) and younger age (P = .049) were independent predictors of the need for intubation. Young patients with large body surface area burns that required large volumes of resuscitation comprise an at-risk group for respiratory failure after a scald injury. Increased vigilance is merited during the resuscitation of these patients.  相似文献   
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Environmental pollution of aquatic ecosystems leads to an interference in several fundamental biochemical and physiological functions. In this study the interference of Cd and Pb pollutions on the physiological growth and subsequently on the age determination was investigated. The hermit crab, Coenobita scaevola (C.s) was selected as a bioaccumulator in this study. The direct and indirect age determination methods were carried out using annual band counts and carapace length, respectively. The results showed that, there was very low correlation (R2?<?0.5) between direct and indirect age determination. Wavelet Neural Network (WNN) was applied to take into account the environmental effects such as the accumulation of Cd and Pb elements in the C.s’ tissues. It was observed that WNN successfully enhanced the growth rate model and estimated the C.s’ age (R2?>?0.95). In addition, it was concluded that the environmental pollution had interaction with the growth physiology such as weight and length.  相似文献   
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