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Data generation remains a bottleneck in training surrogate models to predict molecular properties. We demonstrate that multitask Gaussian process regression overcomes this limitation by leveraging both expensive and cheap data sources. In particular, we consider training sets constructed from coupled-cluster (CC) and density functional theory (DFT) data. We report that multitask surrogates can predict at CC-level accuracy with a reduction in data generation cost by over an order of magnitude. Of note, our approach allows the training set to include DFT data generated by a heterogeneous mix of exchange-correlation functionals without imposing any artificial hierarchy on functional accuracy. More generally, the multitask framework can accommodate a wider range of training set structures-including the full disparity between the different levels of fidelity-than existing kernel approaches based on Δ-learning although we show that the accuracy of the two approaches can be similar. Consequently, multitask regression can be a tool for reducing data generation costs even further by opportunistically exploiting existing data sources.
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INTRODUCTION: While tin prefiltration is established in various CT applications, its value in extremity cone-beam CT relative to optimized spectra has not been thoroughly assessed thus far. This study aims to investigate the effect of tin filters in extremity cone-beam CT with a twin-robotic X-ray system. METHODS: Wrist, elbow and ankle joints of two cadaveric specimens were examined in a laboratory setup with different combinations of prefiltration (copper, tin), tube voltage and current-time product. Image quality was assessed subjectively by five radiologists with Fleiss' kappa being computed to measure interrater agreement. To provide a semiquantitative criterion for image quality, contrast-to-noise ratios (CNR) were compared for standardized regions of interest. Volume CT dose indices were calculated for a 16 cm polymethylmethacrylate phantom. RESULTS: Radiation dose ranged from 17.4 mGy in the clinical standard protocol without tin filter to as low as 0.7 mGy with tin prefiltration. Image quality ratings and CNR for tin-filtered scans with 100 kV were lower than for 80 kV studies with copper prefiltration despite higher dose (11.2 and 5.6 vs. 4.5 mGy; p < 0.001). No difference was ascertained between 100 kV scans with tin filtration and 60 kV copper-filtered scans with 75% dose reduction (subjective: p = 0.101; CNR: p = 0.706). Fleiss' kappa of 0.597 (95% confidence interval 0.567-0.626; p < 0.001) indicated moderate interrater agreement. CONCLUSION: Considerable dose reduction is feasible with tin prefiltration, however, the twin-robotic X-ray system's low-dose potential for extremity 3D imaging is maximized with a dedicated low-kilovolt scan protocol in situations without extensive beam-hardening artifacts. IMPLICATIONS FOR PRACTICE: Low-kilovolt imaging with copper prefiltration provides a superior trade-off between dose reduction and image quality compared to tin-filtered cone-beam CT scan protocols with higher tube voltage.
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Procedimientos Quirúrgicos Robotizados , Estaño , Tomografía Computarizada de Haz Cónico/métodos , Cobre , Extremidades , Humanos , Dosis de Radiación , Rayos XRESUMEN
Climate change will bring warmer and wetter conditions and more frequent extreme events in the Nemoral climate zone. These changes are expected to affect maize growth and yields. In this study, we applied the AgroC model to assess climate change impact on changes in growing environmental conditions, growing season length, yield and potential yield losses due to multiple abiotic stresses. The model was calibrated and validated using data from dedicated field experiments conducted in Lithuania during four meteorologically contrasting years (2015, 2016, 2017 and 2019). We simulated the climate impacts on rainfed maize for long-term future climate conditions from 2020 to 2100 under the RCP2.6 (low), RCP4.5 (medium) and RCP8.5 (high) emission scenarios. As a result, we found that air temperature, sum of growing degree days and amount of precipitation during the growing season of maize will increase, especially under medium and higher emission scenarios (RCP4.5 and RCP8.5), with significantly positive effect on yields. The simulation results showed that average maize grain yield will increase under RCP2.6 by 69 kg ha-1 per decade, under RCP4.5 by 197 kg ha-1 per decade and under RCP8.5 by 304 kg ha-1 per decade. The future potential maize yield reveals a progressive increase with a surplus of +10.2% under RCP4.5 and +14.4% under RCP8.5, while under RCP2.6 the increase of potential yield during the same period will be statistically not significant. The yield gap under RCP2.6 and RCP4.5 will fluctuate within a rather narrow range and under RCP8.5, it will decrease.
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Cambio Climático , Zea mays , Lituania , Estaciones del Año , TemperaturaRESUMEN
BACKGROUND: Anterior shoulder dislocation is common. The treatment of recurrence with glenoid bone defect is still considered controversial. A new arthroscopic subscapularis augmentation has recently been described that functions to decrease the anterior translation of the humeral head. The purpose of the presented study was to examine the biomechanical effect on glenohumeral joint motion and stability. METHODS: Eight fresh frozen cadaver shoulders were studied by use of a force guided industrial robot fitted with a six-component force-moment sensor to which the humerus was attached. The testing protocol includes measurement of glenohumeral translation in the anterior, anterior-inferior and inferior directions at 0°, 30° and 60° of glenohumeral abduction, respectively, with a passive humerus load of 30N in the testing direction. The maximum possible external rotation was measured at each abduction angle applying a moment of 1Nm. Each specimen was measured in a physiologic state, as well as after Bankart lesion with an anterior bone defect of 15-20% of the glenoid, after arthroscopic subscapularis augmentation and after Bankart repair. FINDINGS: The arthroscopic subscapularis augmentation decreased the anterior and anterior-inferior translation. The Bankart repair did not restore the mechanical stability compared to the physiologic shoulder group. External rotation was decreased after arthroscopic subscapularis augmentation compared to the physiologic state, however, the limitation of external rotation was decreased at 60° abduction. INTERPRETATION: The arthroscopic subscapularis augmentation investigated herein was observed to restore shoulder stability in an experimental model.
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Rango del Movimiento Articular/fisiología , Manguito de los Rotadores/fisiología , Manguito de los Rotadores/cirugía , Articulación del Hombro/fisiología , Hombro/fisiología , Hombro/cirugía , Adulto , Fenómenos Biomecánicos , Bursitis/fisiopatología , Cadáver , Femenino , Humanos , Cabeza Humeral , Inestabilidad de la Articulación/cirugía , Masculino , Persona de Mediana Edad , Recurrencia , Rotación , Escápula/cirugía , Luxación del Hombro/cirugía , Cicatrización de HeridasRESUMEN
OBJECTIVE: We aimed to test the hypothesis that slice-by-slice prospective motion correction at 7T using an optical tracking system reduces the rate of false positive activations in an fMRI group study with a paradigm that involves task-correlated motion. MATERIALS AND METHODS: Brain activation during right leg movement was measured using a block design on 15 volunteers, with and without prospective motion correction. Clearly erroneous activations were compared between both cases, at the individual level. Additionally, conventional group analysis was performed. RESULTS: The number of falsely activated voxels with T-values higher than 5 was reduced by 48% using prospective motion correction alone, without additional retrospective realignment. In the group analysis, the statistical power was increased - the peak T-value was 26% greater, and the number of voxels in the cluster representing the right leg was increased by a factor of 9.3. CONCLUSION: Slice-by-slice prospective motion correction in fMRI studies with task-correlated motion can substantially reduce false positive activations and increase statistical power.
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Algoritmos , Artefactos , Mapeo Encefálico/métodos , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Movimiento/fisiología , Femenino , Humanos , Pierna/fisiología , Masculino , Movimiento (Física) , Estudios Prospectivos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estadística como Asunto , Análisis y Desempeño de Tareas , Adulto JovenRESUMEN
Zirconia (ZrO2) thin films with micronic layer thickness are deposited on Si(100) substrates by MOCVD in a cold wall reactor using direct injection (DLI-CVD) process with Zr2(OiPr)6(thd)2 precursor diluted in cyclohexane. The effects of experimental parameters such as substrate's temperature, injection frequency, oxygen partial pressure in the reactive chamber and deposition duration of the process are investigated in order to produce a strongly textured tetragonal ZrO2 film. The films crystalline structure and crystallite size (several nm) are identified by Grazing incidence X-ray diffraction (GIXRD); the microstructure and morphology are observed with the use of FEG-SEM. GIXRD patterns showed the predominance of nano-crystallized tetragonal phase (or cubic) in the films. Pole figures have been analysed for both {111}(t-c) and {200}(t-c) planes in order to evaluate the relationship binding the preferential crystallographic orientation to the column-like growth structure. Besides, the internal stresses levels (with the use of sin2 psi method) within zirconia layers varied from a compressive to a tensile state depending on the experimental deposition conditions and are related to phase orientation and/or transformation into monoclinic one. It is demonstrated that high temperature, low pressure and low deposition time enhanced the tetragonal phase quality that became highly (200)t textured.
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BACKGROUND: Acute exacerbations in allergic asthmatics may lead to impaired ability to clear mucus from the airways, a key factor in asthma morbidity. OBJECTIVE: The purpose of this study was to determine the effect of inhaled house dust mite challenge on the regional deposition of inhaled particles and mucociliary clearance (MCC) in allergic asthmatics. METHODS: We used gamma scintigraphy (inhalation of (99m) Tc -sulphur colloid particles) to measure the regional particle deposition and MCC in allergic asthmatics (n=12) 4 h following an inhaled dust mite allergen challenge (Dermatophagoides farinae extract; PD(max) =fall in forced expiratory volume in 1 s of 10%) for comparison with baseline non-challenge measures. RESULTS: In responders (n=9 PD(max) dose), lung function returned to pre-challenge values by 3 h but was significantly decreased at 6 and 24 h in three of the responders (i.e. late-phase response) and induced sputum eosinophils were increased at 24 h post-challenge (P<0.05). Responders showed enhanced bronchial airway deposition of inhaled particles (P<0.05) and slowed clearance from the central lung zone (P<0.01) at 4 h post-challenge compared with the baseline (no allergen challenge) that was predicted by the PD(max) allergen concentration (r=-0.70, P<0.05). The decline in lung function at 24 h post-challenge correlated with reduced MCC from the central lung zone (r=-0.78, P<0.02) and PD(max) . Non-responders (n=3) showed no change in lung function, regional deposition or MCC post-challenge vs. baseline. CONCLUSIONS AND CLINICAL RELEVANCE: These data suggest that regional deposition and clearance of inhaled particles may be sensitive for detecting mild airway obstruction associated with early- and late-phase allergen-induced effects on mucus secretions. The study was listed on clinicaltrials.gov (NCT00448851).
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Antígenos Dermatofagoides/inmunología , Asma/inmunología , Depuración Mucociliar/inmunología , Pyroglyphidae/inmunología , Administración por Inhalación , Adulto , Animales , Antígenos Dermatofagoides/administración & dosificación , Asma/fisiopatología , Pruebas de Provocación Bronquial , Broncoespirometría , Eosinófilos/inmunología , Femenino , Volumen Espiratorio Forzado , Humanos , Recuento de Leucocitos , Masculino , Neutrófilos/inmunología , Esputo/citología , Esputo/inmunología , Adulto JovenRESUMEN
BACKGROUND: No standard treatment for locally advanced pancreatic cancer (LAPC) is defined. PATIENTS AND METHODS: Within a multi-centre, randomised phase II trial, 95 patients with LAPC were assigned to three different chemoradiotherapy (CRT) regimens: patients received conventionally fractionated radiotherapy of 50 Gy and were randomised to concurrent 5-fluorouracil (350 mg m(-2) per day on each day of radiotherapy, RT-5-FU arm), concurrent gemcitabine (300 mg m(-2)), and cisplatin (30 mg m(-2)) on days 1, 8, 22, and 29 (RT-GC arm), or the same concurrent treatment followed by sequential full-dose gemcitabine (1000 mg m(-2)) and cisplatin (50 mg m(-2)) every 2 weeks (RT-GC+GC arm). Primary end point was the overall survival (OS) rate after 9 months. RESULTS: The 9-month OS rate was 58% in the RT-5-FU arm, 52% in the RT-GC arm, and 45% in the RT-GC+GC arm. Corresponding median survival times were 9.6, 9.3, and 7.3 months (P=0.61) respectively. The intent-to-treat response rate was 19, 22, and 13% respectively. Median progression-free survival was estimated with 4.0, 5.6, and 6.0 months (P=0.21). Grade 3/4 haematological toxicities were more frequent in the two GC-containing arms, no grade 3/4 febrile neutropaenia was observed. CONCLUSION: None of the three CRT regimens tested met the investigators' definition for efficacy; the median OS was similar to those previously reported with gemcitabine alone in LAPC.
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Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/radioterapia , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Fluorouracilo/uso terapéutico , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/radioterapia , Adenocarcinoma/patología , Adolescente , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Cisplatino/administración & dosificación , Cisplatino/efectos adversos , Desoxicitidina/administración & dosificación , Desoxicitidina/efectos adversos , Desoxicitidina/análogos & derivados , Supervivencia sin Enfermedad , Esquema de Medicación , Femenino , Fluorouracilo/efectos adversos , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias Pancreáticas/patología , Tasa de Supervivencia , Adulto Joven , GemcitabinaRESUMEN
This study was undertaken to examine the role of K(+) channels on cytosolic Ca(2+) ([Ca(2+)](i)) in insulin secreting cells. [Ca(2+)](i) was measured in single glucose-responsive INS-1 cells using the fluorescent Ca(2+) indicator Fura-2. Glucose, tolbutamide and forskolin elevated [Ca(2+)](i) and induced [Ca(2+)] oscillations. Whereas the glucose effect was delayed and observed in 60% and 93% of the cells, in a poorly and a highly glucose-responsive INS-1 cell clone, respectively, tolbutamide and forskolin increased [Ca(2+)](i) in all cells tested. In the latter clone, glucose induced [Ca(2+)](i) oscillations in 77% of the cells. In 16% of the cells a sustained rise of [Ca(2+)](i) was observed. The increase in [Ca(2+)](i) was reversed by verapamil, an L-type Ca(2+) channel inhibitor. Adrenaline decreased [Ca(2+)](i) in oscillating cells in the presence of low glucose and in cells stimulated by glucose alone or in combination with tolbutamide and forskolin. Adrenaline did not lower [Ca(2+)](i) in the presence of 30mM extracellular K(+), indicating that adrenaline does not exert a direct effect on Ca(2+) channels but increases K(+) channel activity. As for primary b-cells, [Ca(2+)](i) oscillations persisted in the presence of closed K(ATP) channels; these also persisted in the presence of thapsigargin, which blocks Ca(2+) uptake into Ca(2+) stores. In contrast, in voltage-clamped cells and in the presence of diazoxide (50mM), which hyperpolarizes the cells by opening K(ATP) channels, [Ca(2+)](i) oscillations were abolished. These results support the hypothesis that [Ca(2+)](i) oscillations depend on functional voltage-dependent Ca(2+) and K(+) channels and are interrupted by a hyperpolarization in insulin-secreting cells.
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Señalización del Calcio/fisiología , Calcio/metabolismo , Insulina/metabolismo , Potenciales de la Membrana/fisiología , Canales de Potasio/metabolismo , Agonistas alfa-Adrenérgicos/farmacología , Antagonistas Adrenérgicos alfa/farmacología , Animales , Línea Celular , Clonidina/farmacología , Colforsina/farmacología , Diazóxido/farmacología , Inhibidores Enzimáticos/farmacología , Epinefrina/farmacología , Colorantes Fluorescentes/metabolismo , Fura-2/metabolismo , Glucosa/farmacología , Hipoglucemiantes/farmacología , Secreción de Insulina , Islotes Pancreáticos/citología , Islotes Pancreáticos/fisiología , Ratones , Técnicas de Placa-Clamp , Prazosina/farmacología , Receptores Adrenérgicos alfa 2/metabolismo , Tapsigargina/farmacología , Tolbutamida/farmacologíaRESUMEN
PURPOSE: The aim of this paper is to find techniques for quantifying radiation lung injury after irradiation with lung involvement to improve an early diagnosis. METHODS: The case of a patient with NSCLC was used to demonstrate different methods in order to quantify a developing pneumopathy after radiation treatment. By means of HRCT studies in the follow-up, a procedure was developed by defining a test-ROI in high-dose areas of the lung and evaluating the corresponding HU-histogramm for the parameters of the lung peak. Changes during the follow-up can be derived from the differential HU-histogram by the determination of a parameter called delta HUrel, which quantifies the shift to higher HU values. Alternatively, a Fourier analysis of the lung pattern within the test-ROI results in a Fourier amplitude distribution, which reacts sensitively to changes during the follow-up. Furthermore, a Fourier-frequency histogram can be derived which is independent of the spatial orientation of the density pattern. RESULTS: From the HRCT follow-up study, values for delta HUrel can be derived to be 0.24, 0.44, and 0.50 (56, 100 and 422 days after beginning the treatment). The differential Fourier frequency-histogram presentations demonstrate pronounced pattern changes. CONCLUSION: The presented methods demonstrate possibilities to quantify radiation lung injury. The proven sensitivity can possibly be improved after the introduction of a breath triggered HRCT technique.
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Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Neoplasias Pulmonares/radioterapia , Pulmón/efectos de la radiación , Traumatismos por Radiación/diagnóstico por imagen , Radioterapia/efectos adversos , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Pulmón/diagnóstico por imagen , Traumatismos por Radiación/etiología , Dosificación Radioterapéutica , Tomografía Computarizada por Rayos XRESUMEN
The aim of the present study was to investigate whether mechanisms distal to the regulation of Ca2-influx are involved in tolbutamide-induced stimulation and adrenaline- and somatostatin- induced inhibition of insulin secretion in INS-1 cells. Using the patch clamp method, the membrane voltage was either kept constant at -70 mV, or Ca2+-influx was activated by short depolarising pulses to 0 my. These pulses induced an increase in cellular capacitance (Cm) caused by fusion of secretory granules with the plasma membrane. Tolbutamide did not alter, neither Cm under voltage clamp at -70 mV nor increases of Cm due to voltage pulses. The inhibitors of secretion, adrenaline and somatostatin, counteracted the augmentation of [Ca2+]i which was induced by glucose, tolbutamide and forskolin. In the voltage clamp mode, however, where no changes of [Ca2]i. were observed, adrenaline but not somatostatin inhibited the increase of Cm caused by depolarizing voltage pulses. The adrenaline effect on Cm was dependent on the addition of GTP to the pipette solution. When GTP was replaced by GDPbetaS or GTPgammaS, the effect of adrenaline on Cm was abolished. The blockade of calcineurin, by the addition of calcineurin inhibitory peptide (CIP) to the pipette solution, did not affect the adrenaline-induced inhibition of Cm. Moreover. After incubation of the cells with deltamethrin, a calcineurin inhibitor, the stimulation of secretion was attenuated, but the adrenaline-induced inhibition was not affected. Our results suggest that adrenaline-induced inhibition of insulin secretion involves a site of action directly related to the exocytotic membrane fusion. In contrast, the stimulator tolbutamide and the inhibitor somatostatin had no direct effect on exocytosis in INS-1 cells.
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Epinefrina/farmacología , Insulina/metabolismo , Tolbutamida/farmacología , Línea Celular , Exocitosis , Secreción de Insulina , Potenciales de la Membrana , Nitrilos , Técnicas de Placa-Clamp , Piretrinas/farmacología , Somatostatina/farmacología , Análisis EspectralRESUMEN
OBJECTIVES: To develop and test a standardized instrument, the purpose of which is to assess (1) whether skilled nursing facilities (SNFs) transfer residents to emergency departments (ED) inappropriately, (2) whether residents are admitted to hospitals inappropriately, (3) and factors associated with inappropriate transfers. DESIGN: A structured implicit review (SIR) of medical records. SETTING AND PARTICIPANTS: Using nested random sampling in eight community SNFs, we identified SNF and hospital records of 100 unscheduled transfers to one of 10 hospitals. MEASUREMENTS: Seven trained physician reviewers assessed appropriateness using a SIR form designed for this study (2 independent reviews per record, 200 total reviews). We measured interrater reliability with kappa statistics and used bivariate analysis to identify factors associated with assessment that transfer was inappropriate. RESULTS: In 36% of ED transfers and 40% of hospital admissions, both reviewers agreed that transfer/admit was inappropriate, meaning the resident could have been cared for safely at a lower level of care. Agreement was high for both ED (percent agreement 84%, kappa .678) and hospital (percent agreement 89%, kappa .779). When advance directives were considered, both reviewers rated 44% of ED transfers and 45% of admissions inappropriate. Factors associated with inappropriateness included the perceptions that: (1) poor quality of care contributed to transfer need, (2) needed services would typically be available in outpatient settings, and (3) the chief complaint did not warrant hospitalization. CONCLUSIONS: Inappropriate transfers are a potentially large problem. Some inappropriate transfers may be associated with poor quality of care in SNFs. This study demonstrates that structured implicit review meets criteria for reliable assessment of inappropriate transfer rates. Structured implicit review may be a valuable tool for identifying inappropriate transfers from SNFs to EDs and hospitals.
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Toma de Decisiones , Servicio de Urgencia en Hospital , Transferencia de Pacientes , Instituciones de Cuidados Especializados de Enfermería , Directivas Anticipadas , Anciano , Anciano de 80 o más Años , Atención Ambulatoria/estadística & datos numéricos , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Necesidades y Demandas de Servicios de Salud/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Variaciones Dependientes del Observador , Admisión del Paciente/estadística & datos numéricos , Transferencia de Pacientes/estadística & datos numéricos , Calidad de la Atención de Salud , Reproducibilidad de los Resultados , Estudios Retrospectivos , Instituciones de Cuidados Especializados de Enfermería/estadística & datos numéricosAsunto(s)
Investigación Metodológica en Enfermería/métodos , Proyectos de Investigación , Actitud del Personal de Salud , Ética en Enfermería , Salud Holística , Humanos , Consentimiento Informado , Relaciones Enfermero-Paciente , Defensa del Paciente , Filosofía en Enfermería , Investigadores/psicologíaRESUMEN
PURPOSE: The goal of the second German Soft Tissue Sarcoma Study CWS-86 (1985 to 1990) was to improve the prognosis in children and adolescents with soft tissue sarcoma by means of a clinical trial comprising intensive chemotherapy and risk-adapted local therapy. PATIENTS AND METHODS: There were 372 eligible patients. A staging system based on the postsurgical extent of disease was used. Chemotherapy consisted of vincristine, dactinomycin, doxorubicin, and ifosfamide. Radiotherapy was administered early at 10 to 13 weeks simultaneously with the second chemotherapy cycle (32 Gy or 54. 4 Gy). The single dose was reduced to 1.6 Gy and given twice daily (accelerated hyperfractionation). RESULTS: The event-free survival (EFS) and overall survival rates at 5 years were 59% +/- 3% and 69% +/- 3%, respectively. The 5-year EFS rate according to stage was as follows: stage I, 83% +/- 5%; stage II, 69% +/- 6%; stage III, 57% +/- 4%; and stage IV, 19% +/- 6%. The outcome for patients with stage III disease who required radiotherapy was much better in the CWS-86 study compared with the CWS-81 study (5-year EFS, 60% +/- 5% v 44% +/- 6%; P =.053). The most common treatment failure was isolated local relapse, with 14% of patients relapsing at the primary tumor site. CONCLUSION: The improved design of the study incorporating risk-adapted radiotherapy allowed treatment to be reduced for selected groups of patients without compromising survival.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Sarcoma/tratamiento farmacológico , Sarcoma/radioterapia , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Niño , Preescolar , Terapia Combinada , Ciclofosfamida/administración & dosificación , Dactinomicina/administración & dosificación , Dactinomicina/efectos adversos , Supervivencia sin Enfermedad , Doxorrubicina/administración & dosificación , Doxorrubicina/efectos adversos , Femenino , Humanos , Ifosfamida/administración & dosificación , Ifosfamida/efectos adversos , Masculino , Evaluación de Resultado en la Atención de Salud , Cuidados Preoperatorios , Pronóstico , Recurrencia , Proyectos de Investigación , Terapia Recuperativa , Sarcoma/mortalidad , Vincristina/administración & dosificación , Vincristina/efectos adversosRESUMEN
Two reaction-time experiments using the psychological refractory period paradigm examined whether two prominent tasks, i.e., mental rotation and memory scanning, require access to a single-channel mechanism and must therefore be performed sequentially with other operations requiring the same mechanism. On each trial, subjects made speeded responses to a tone (Exp. 1) or a character (Exp. 2, with symbolic SR-compatibility of the character manipulated) as Task 1 and to a letter (for blocks with mental rotation) or a digit (for blocks with memory scanning) as Task 2. The set-size effect was constant across SOAs, suggesting that memory scanning cannot be performed in parallel with response selection of Task 1. The effect of orientation, however, decreased with decreasing SOA. The decrease was even intensified if Task 1 bottleneck processes were prolonged by symbolic SR-compatibility. The exact pattern of underadditivity, however, was not predicted by current theories of dual-task performance. The results contradict a central bottleneck model but are in line with extensions of the model proposed by Meyer and Kieras.
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Memoria/fisiología , Procesos Mentales/fisiología , Percepción de Movimiento/fisiología , Femenino , HumanosRESUMEN
Objetivos: Valorar indicadores psicológicos, sociales y físicos así como hallazgos génito-anales y Enfermedades Sexualmente Transmisibles (EST) en 70 casos certeros de Abuso Sexual (AS). Resultados: Hallazgos génito-anales: * Grupo IA Normal 8,70 por ciento. * Grupo IB Inespecíficos 13,04 por ciento. * Grupo II Sugestivo Abuso Sexual (SAS) 42,03 por ciento. * Grupo III Concluyente Abuso Sexual (ConAS) 34,78 por ciento. * Grupo IV Certeza Abuso Sexual (CerAS) 1,45 por ciento. Hallazgos microbiológicos: Grupo I (Inespecífico): Flora endógena 58,62 por ciento, Patógenos Respiratorios 6,90 por ciento o Intestinales 6,90 por ciento. Grupo II (SAS): G. vaginalis 6,90 por ciento, U. urealyticum 3,45 por ciento, HSV, HPV. Grupo III (ConAS): G. trachomatis > 4 años 31,82 por ciento; T. vaginales > 1 año 3,45 por ciento. Grupo IV (CerAS): N. gonorrhoeae; Sífilis; HIV. Conclusiones: 1. Relato de la niña en 87,14 por ciento; 2. AS intrafamiliar 68,57 por ciento, AS extrafamiliar 24,28 por ciento y no supo en 7,14 por ciento; 3. De los casos intrafamiliares, en 43,75 por ciento el abusador fue el padre; 4. Hallazgos genito-anales SAS 42,03 por ciento y ConAS 34,78 por ciento. Estos índices se modifican a 33,33 por ciento y 46,37 por ciento, al incorporar EST en el criterio diagnóstico; 5. Si bien la vulvovaginitis es un signo inespecífico, el hallazgo de EST en 31,03 por ciento obliga a cultivar las niñas con flujo persistente y/o intermitente; 6. Violencia familiar 45,71 por ciento y alcoholismo y otras drogas 27,14 por ciento; 7. Antecedentes AS en madre o padre 27,14 por ciento; 8. Trastornos escolares 46,15 por ciento; 9. Pareja parental oroginal ya no existía en 70 por ciento
Asunto(s)
Humanos , Femenino , Preescolar , Abuso Sexual Infantil/diagnóstico , Violación/diagnóstico , Abuso Sexual Infantil/psicología , Abuso Sexual Infantil/estadística & datos numéricos , Maltrato a los Niños/diagnóstico , Encuestas Sanitarias acerca de Suministro de Agua , Delitos Sexuales/estadística & datos numéricos , Factores Socioeconómicos , Violación/estadística & datos numéricos , Violación/psicologíaRESUMEN
BACKGROUND: Blood and blood products are irradiated to avoid the graft-versus-host disease (GVHD) in immunosuppressed patients and to destroy tumor cells during the intra-operative autotransfusion in tumor surgery. For that purpose more and more dedicated gamma irradiators are used. In most cases the equipment is supplied with a dose calibration factor for a totally filled irradiation canister. As users handle different blood product volumes, it is necessary to investigate the influence of the irradiated blood volume on the absolute dose in a reference point and the dose distribution in the irradiation volume. MATERIAL AND METHODS: The dose rate in the center of an empty irradiation canister of an IBL 437C blood irradiator (CIS Diagnostic) was investigated by means of Fricke solution dosimeters from the Physikalisch-Technische Bundesanstalt (PTB). Using thermoluminescence dosimetry (TLD) this value could be transferred to a situation with an empty or completely filled respectively with 2 blood samples (270 ml each) filled canister. Also essential for the irradiation of blood is the knowledge of the dose distribution in the irradiated volume. The distributions in the empty and the realistic filled canister were measured by positioning the TLD on the plexiglas holder in a regular pattern. The case of a completely filled container was investigated by means of the MR Fricke gel dosimetry. All distributions are presented as dose-volume-histograms (DVH). RESULTS: The TLD-measurement in the center of the completely filled canister yielded a 4.8% higher dose rate value as compared to the suppliers certificate. From the investigations using the Fricke solution dosimeters in air combined with TLD-measurements values for the complete bandwidth of different container fillings could be derived. So the dose rate in the centre of the canister in the boundary conditions empty and full canister as compared to the values for the realistic filling condition (2 bags) are 117.5% and 94% respectively. Axial dose distributions and DVH have been determined for the 3 filling conditions. CONCLUSIONS: We recommend a dose calibration measurement of a blood irradiator to determine the irradiation times for the chosen filling condition, which is typical for the hospital. The DVH presented in this work can be used to derive a value for the dose variance within the irradiated blood.