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PURPOSE: Ifosfamide, carboplatin, and etoposide (ICE) are associated with grade III/IV dose-limiting thrombocytopenia. The Children's Oncology Group conducted a phase I dose escalation, pharmacokinetic, and biological study of recombinant human thrombopoietin (rhTPO) after ICE in children with recurrent/refractory solid tumors (CCG-09717) to assess the toxicity and maximum tolerated dose of rhTPO administered at 1.2, 2.4, or 3.6 microg/kg per dose. EXPERIMENTAL DESIGN: Children received ifosfamide 1,800 mg/m2 on days 0 to 4, carboplatin 400 mg/m2 on days 0 to 1, and etoposide 100 mg/m2 on days 0 to 4. rhTPO was administered i.v. on days +4, +6, +8, +10, and +12 at 1.2, 2.4, or 3.6 microg/kg per dose.RESULTS: rhTPO was well tolerated and maximum tolerated dose was not reached. Median time to platelet recovery > or =100,000/microL of rhTPO at 1.2, 2.4, and 3.6 microg/kg/d was 24 days (22-24 d), 25 days (23-29 d), and 22 days (16-37 d), respectively. Patients required a median of 2 days of platelet transfusions (0-7 days). Mean (+/- SD) rhTPO maximum serum concentrations were 63.3 +/- 9.7 and 89.3 +/- 15.7 ng/mL and terminal half-lives were 47 +/- 13 and 64 +/- 42 hours after 2.4 and 3.6 microg/kg/d, respectively. There was a significant increase in colony-forming unit megakaryocyte upon WBC count recovery. CONCLUSIONS: rhTPO was well tolerated. Time to hematologic recovery and median number of platelet transfusions seem to be improved compared with historical controls receiving ICE + granulocyte colony-stimulating factor (CCG-0894).  相似文献   
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AimTo comprehensively describe intellectual and executive functioning (EF) in people with dyskinetic cerebral palsy (DCP), by comparing their performance with that of: 1) age- and sex-matched typically developing controls (TDC); and 2) participants with spastic cerebral palsy (SCP) matched for age, sex, term/preterm and gross motor function classification system (GMFCS).MethodThis cross-sectional study was conducted by the University of Barcelona in collaboration with five institutions. Participants were people with DCP (n = 52; 24 females, median age 20.5 y: 5mo, interquartile range [IQR] = 13.75 y: 7mo; GMFCS I–V). As comparison groups, participants with SCP (n = 20; 10 females, median age = 20.5 y: 5.5mo, IQR = 13.75 y 9mo; GMFCS I–V) and TDC (n = 52; 24 females, median age = 20 y: 4mo, IQR = 12 y 7mo) were included. Intelligence and EF were assessed using common tests in all participants.ResultsBoth CP groups had lower intelligence than TDC and performed poorer in almost all EF tasks. Intelligence was higher in DCP than SCP (z = ?2.51, p = 0.01). Participants with DCP also performed significantly better in goal-setting tasks (z = 2.27, p = 0.03) and information processing (z = ?2.54, p = 0.01) than those with SCP.ConclusionPeople with DCP present lower general intellectual functioning and poorer EF across multiple domains than typically developing controls. People with DCP have higher general intellectual functioning and better EF than people with SCP when levels of motor severity are similar.  相似文献   
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The problem of diffusion-controlled growth following an instantaneous nucleation event was studied within the framework of a new numerical model, considering the spatial distribution of hemispherical nuclei on the electrode surface and the mutual influence of growing nuclei via the collision of 3D diffusion fields. The simulation of the diffusion-controlled growth of hexagonal and random ensembles was performed at the overpotential-dependent number density of nuclei. The diffusion flow to each nucleus within a random ensemble was simulated by the finite difference method using the derived analytical expressions for the surface areas and the volumes formed at the intersection of 3D diffusion fields with the side faces of a virtual right prism with a Voronoi polygon base. The implementation of this approach provides an accurate calculation of concentration profiles, time dependences of the size of nuclei, and current transients. The results, including total current density transients, growth exponents, and nucleus size distribution, were compared with models developed within the concept of planar diffusion zones, the mean-field approximation and the Brownian dynamics simulation method, as well as with experimental data from the literature. The prospects of the model for studying the initial stages of electrocrystallization were discussed.  相似文献   
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This study built theoretical and practical models to evaluate the corrosion resistance of concrete for coastal offshore structures in Vietnam. A mathematical model was developed in the form of a system of nonlinear partial differential equations characterizing the diffusion “free calcium hydroxide” in a solid of a concrete structure. The model describes the process of non-stationary mass conductivity observed in the “concrete structure—marine environment” system under non-uniform arbitrary initial conditions, as well as combined boundary conditions of the second and third kind, taking into account the nonlinear nature of the coefficients of mass conductivity k and mass transfer β. It was shown that the solution of the boundary value problem of non-stationary mass conductivity allows us to conclude about the duration of the service life of a concrete structure, which will be determined by the processes occurring at the interface: in concrete—mass conductivity, depending on the structural and mechanical characteristics of hydraulic structures, and in the liquid phase—mass transfer, determined by the conditions of interaction at the interface of the indicated phases.  相似文献   
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PurposeTo study the clinical signs and mechanisms (viral and autoimmune) of myoendocarditis in the long‐term period after COronaVIrus Disease 2019 (COVID‐19).MethodsFourteen patients (nine male, 50.1 ± 10.2 y.o.) with biopsy proven post‐COVID myocarditis were observed. The diagnosis of COVID‐19 was confirmed by IgG seroconversion. The average time of admission after COVID‐19 was 5.5 [2; 10] months. An endomyocardial biopsy (EMB) of the right ventricle was obtained. The biopsy analysis included polymerase chain reaction diagnosis of viral infection, morphological, immunohistochemical (IHC) examination with antibodies to CD3, CD45, CD68, CD20, SARS‐Cov‐2 spike, and nucleocapsid antigens. Coronary atherosclerosis was ruled out in all patients over 40 years.ResultsThe new cardiac symptoms (congestive heart failure 3–4 New York Heart Association class with severe right ventricular involvement, various rhythm, and conduction disturbances) appeared 1–5 months following COVID‐19. Magnetic resonance imaging showed disseminated or focal subepicardial and intramyocardial late gadolinium enhancement, hyperemia, edema, and increased myocardial native T1 relaxation time. Antiheart antibodies levels were increased 3–4 times in 92.9% of patients. The mean left ventricular (LV) ejection fraction (EF) was 28% (24.5; 37.8). Active lymphocytic myocarditis was diagnosed in 12 patients, eosinophilic myocarditis in two patients. SARS‐Cov‐2 RNA was detected in 12 cases (85.7%), in association with parvovirus B19 DNA—in one. Three patients had also endocarditis (infective and nonbacterial, with parietal thrombosis). As a result of steroid and chronic heart failure therapy, the EF increased to 47% (37.5; 52.5).ConclusionsCOVID‐19 can lead to long‐term severe post‐COVID myoendocarditis, that is characterized by prolonged persistence of coronavirus in cardiomyocytes, endothelium, and macrophages (up to 18 months) in combination with high immune activity. Corticosteroids and anticoagulants should be considered as a treatment option of post‐COVID myoendocarditis.  相似文献   
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INTRODUCTION: Psychological factors are believed to play an important role in infertility and its treatment Psychological problems may be considered to be risk factors and the cause of reduced infertility, as well as contribute to an unsuccessful outcome of infertility treatment. OBJECTIVES: The aim of the study was to investigate the correlation between semen parameters and quality of life in male patients with fertility problems. MATERIAL AND METHODS: 70 patients with infertility treated in Andrology Clinic were divided into two groups according to semen parameters: bad and good quality of semen. The quality of life has been with the help of Campbell questionnaires. RESULTS: Significantly lower questionnaire score in bad quality of semen group has been observed, in comparison with normozoospermic men. High correlation between concentration, motility and morphology in comparison with the quality of life has been observed in the studied group of patients. CONCLUSION: The quality of life is directly associated with semen parameters such as concentration, motility and morphology of sperm.  相似文献   
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