Search results for "Models"
showing 10 items of 8211 documents
A CAD system for nodule detection in low-dose lung CTs based on region growing and a new active contour model
2007
A computer-aided detection (CAD) system for the selection of lung nodules in computer tomography (CT) images is presented. The system is based on region growing (RG) algorithms and a new active contour model (ACM), implementing a local convex hull, able to draw the correct contour of the lung parenchyma and to include the pleural nodules. The CAD consists of three steps: (1) the lung parenchymal volume is segmented by means of a RG algorithm; the pleural nodules are included through the new ACM technique; (2) a RG algorithm is iteratively applied to the previously segmented volume in order to detect the candidate nodules; (3) a double-threshold cut and a neural network are applied to reduce…
Relationships between adipose tissues and brain: what do we learn from animal studies?
2010
International audience; Over the last decades, more and more data supporting the importance of the relationships between the brain and adipose tissues (white and brown) in regards of body weight regulation and energy homeostasis have been published. Indeed the brain via the autonomic nervous system participates to the regulation of different parameters such as the metabolic (lipolysis, lipogenesis and thermogeneis), and secretory (leptin and other adipokines) activities but also plasticity (proliferation differentiation and apoptosis) of adipose tissues. In turn the various fat pads will send information via sensory innervation of white adipose tissue as well as metabolic and hormonal signa…
Dimensional stability of contemporary irreversible hydrocolloids: humidor versus wet tissue storage.
2012
Statement of problem The storage time and conditions of irreversible hydrocolloid impressions affect their accuracy and in turn the precision of the definitive cast. Recommendations for proper storage are, however, based on theoretical assumptions rather than facts. Purpose The purpose of this study was to assess the influence of the 2 most common storage conditions on the dimensional stability of 7 contemporary irreversible hydrocolloids (IH) for a period of up to 7 days. Material and methods Twelve specimens per material (Blueprint, Cavex CA37, Cavex ColorChange, Jeltrate, Orthoprint, Cavex Orthotrace, and Tetrachrom) were fabricated according to ISO/CD 21563. The specimens were either st…
Effect of chest compressions only during experimental basic life support on alveolar collapse and recruitment
2007
Summary Aim The importance of ventilatory support during cardiac arrest and basic life support is controversial. This experimental study used dynamic computed tomography (CT) to assess the effects of chest compressions only during cardiopulmonary resuscitation (CCO-CPR) on alveolar recruitment and haemodynamic parameters in porcine model of ventricular fibrillation. Materials and methods Twelve anaesthetized pigs (26±1kg) were randomly assigned to one of the following groups: (1) intermittent positive pressure ventilation (IPPV) both during basic life support and advanced cardiac life support, or (2) CCO during basic life support and IPPV during advanced cardiac life support. Measurements w…
Effects of calcium, dairy product, and vitamin D supplementation on bone mass accrual and body composition in 10-12-y-old girls: a 2-y randomized tri…
2005
Little is known about the relative effectiveness of calcium supplementation from food or pills with or without vitamin D supplementation for bone mass accrual during the rapid growth period.The purpose was to examine the effects of both food-based and pill supplements of calcium and vitamin D on bone mass and body composition in girls aged 10-12 y.This placebo-controlled intervention trial randomly assigned 195 healthy girls at Tanner stage I-II, aged 10-12 y, with dietary calcium intakes900 mg/d to 1 of 4 groups: calcium (1000 mg) + vitamin D3 (200 IU), calcium (1000 mg), cheese (1000 mg calcium), and placebo. Primary outcomes were bone indexes of the hip, spine, and whole body by dual-ene…
Prediction of dilutional acidosis based on the revised classical dilution concept for bicarbonate
2004
Due to the controversy surrounding the term dilutional acidosis, the classical dilution concept for bicarbonate has been rigorously revised for the prediction of pH, actual bicarbonate concentration, and base excess. In the algorithms derived for buffer solutions, blood, and whole body (1-, 2-, and 3-fluid compartment), only bicarbonate is considered. On dilution at constant Pco2, the final concentration of bicarbonate is the sum in terms of pH, due to the following processes: dilution, formation from chemical reaction with the nonbicarbonate buffers phosphate, hemoglobin, and plasma proteins, and transfer from erythrocytes and interstitial fluid to plasma. At constant Pco2, the level of c…
The impact of occult renal failure on the cardiovascular risk stratification in an elderly population: the PREV-ICTUS study.
2008
To analyze the impact of occult renal failure (ORF) in the individual risk stratification and on the blood pressures (BP) and low-density lipoprotein (LDL) goals in an aged population, according to the ESH/ESC Hypertension Guidelines.A cross-sectional, population-based study on individuals aged 60 years or more carried out in Primary Care Centers of Spain. Kidney function was estimated from calculated creatinine clearance (eGFR), Cockroft and Gault formula. Ten-year cardiovascular risk was estimated through the ESH/ESC table including or not including the eGFR. Estimates of the modification in BP and LDL-cholesterol (cLDL) goals were calculated.In 6419 subjects, 4242 subjects (66%) had norm…
Comprehensive pharmacokinetic model of insulin Glargine and other insulin formulations.
2005
In this paper, a comprehensive pharmacokinetic model for different insulin formulations including insulin Glargine is developed based on the model proposed by Trajanoski et al. (1993). Current models show limitations for insulin Glargine due to the appearance of an uncharacteristic peak in the concentration-time evolution of plasma insulin that does not coincide with real experimental data. This important limitation has been solved in this paper by introducing a new virtual insulin state called the bound state, in addition to the dimeric and hexameric ones. Trying to describe the retarded action of insulin Glargine, the modeling idea behind this approach is that immediately after the subcut…
Stabilization of Perivascular Mast Cells by Endothelial CNP (C-Type Natriuretic Peptide)
2020
Objective: Activated perivascular mast cells (MCs) participate in different cardiovascular diseases. Many factors provoking MC degranulation have been described, while physiological counterregulators are barely known. Endothelial CNP (C-type natriuretic peptide) participates in the maintenance of vascular barrier integrity, but the target cells and mechanisms are unclear. Here, we studied whether MCs are regulated by CNP. Approach and Results: In cultured human and murine MCs, CNP activated its specific GC (guanylyl cyclase)-B receptor and cyclic GMP signaling. This enhanced cyclic GMP–dependent phosphorylation of the cytoskeleton-associated VASP (vasodilator-stimulated phosphoprotein) and…
Hepatocellular Hyperplasia, Plasmacytoma Formation, and Extramedullary Hematopoiesis in Interleukin (IL)-6/Soluble IL-6 Receptor Double-Transgenic Mi…
1998
Cytokines interact not only with membrane anchored receptors, but also with specific soluble receptors which circulate in the bloodstream. In general, soluble cytokine receptors such as soluble tumor necrosis factor receptor, soluble interleukin 1 receptor, and soluble interleukin 4 receptor compete with their membrane-bound counterparts for the ligands and therefore act as antagonists. In contrast, soluble receptors for cytokines of the interleukin-6 (IL-6) family complex with their ligands act agonistically. Interestingly, the complex of IL-6 and the soluble interleukin 6 receptor (sIL-6R) activates target cells that do not express the membrane-bound IL-6R and therefore cannot respond to …