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Measures of quantum properties are essential to understanding the fundamental differences between quantum and classical systems as well as quantifying resources for quantum technologies. Here, two broad classes of bosonic phase-space functions, which are filtered versions of the Glauber-Sudarshan P function, are compared with regard to their ability to uncover nonclassical effects of light through their negativities. Gaussian filtering of the P function yields the family of s-parametrized quasiprobabilities, while more powerful regularized nonclassicality quasiprobabilities are obtained by non-Gaussian filtering. A method is proposed to directly sample such phase-space functions for the restricted case of phase-independent quantum states from balanced homodyne measurements. This overcomes difficulties of previous approaches that manually append uniformly distributed optical phases to the measured quadrature data. We experimentally demonstrate this technique for heralded single- and two-photon states using balanced homodyne detection with varying efficiency. The s-parametrized quasiprobabilities, which can be directly sampled, are non-negative for detection efficiencies below 0.5. By contrast, we show that significant negativities of non-Gaussian filtered quasiprobabilities uncover nonclassical effects for arbitrarily low efficiencies.
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BACKGROUND: On 31 December 2016, a total of 1206 physicians participated in the outpatient care of chronic pain patients according to the criteria of a special pain management program (QSV). Because of the largely existing shortage of treatment resources for chronic pain patients, there is a lack of data regarding the evaluation of outpatient pain management by highly specialized pain therapists. METHODS: In a hybrid Delphi procedure, a questionnaire concerning the content, structural and personal assessment of outpatient pain management in Germany was developed. With the help of this instrument, an internet-based cross-sectional survey of 281 QSV pain therapists from four German states (Berlin, Lower Saxony, Saxony, Baden-Württemberg) and of all the heads of university outpatient pain services (nâ¯= 36) in Germany was conducted. RESULTS: The adjusted response rate of the survey was 35.9%. The response rate of the heads of university outpatient pain services was 66.7%. In 91% of the respondents the proportion of chronic pain patients in the medical practices was more than 70%. Whereas 67.3% were satisfied with the situation in their medical practice, 63.4% were dissatisfied with the current organizational structure of the pain management in Germany. They expressed their dissatisfaction especially in terms of budgeting regulations (69.3%), the cooperation with psychotherapists (69.3%) and interdisciplinary networking (50.5%). The 1year specialist training in pain management (87.1%) and the completion of a psychosomatic basic care course (90.1%) were assessed as a good preparation for the later profession. A multitude of free comments indicated that the pain specialist training is too short and insufficient. Most of the respondents considered the establishment of a specialist board certification for pain management more suitable from the perspective of physicians (61.4%) and the patients (54.5%). Of the heads of university outpatient pain services 70.8% expressed the wish for autonomous structures with separate budgets and 75.0% indicated that under the current conditions their outpatient pain services are not working profitably. Only 39.7% of the QSV pain therapists provided fellowship training for physicians and 57.6% were planning to retire during the next 10 years. CONCLUSION: Highly specialized pain therapists are dissatisfied because of the lack of independence of the organizational structure of pain management care and the insufficient interdisciplinary network in outpatient pain management. A possible solution for a better pain management care and the recruitment problems may be the establishment of a board certification for pain management.
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Pacientes Ambulatorios , Manejo del Dolor , Berlin , Estudios Transversales , Alemania , Humanos , Internet , EspecializaciónRESUMEN
Black-backed jackals (Canis mesomelas) are small meso-predators that occur in the wild and around cities and towns in southern Africa and have been associated with the spread of rabies in South Africa. Oral bait rabies vaccine has been used in Europe and the USA for the control of rabies in reservoir species. The effectiveness of an oral vaccination strategy depends not only on the efficacy of the vaccine but on the uptake of the bait in the target species. This study evaluated factors associated with the uptake of oral bait by free ranging jackal and other wildlife species in a multi-site field study in Gauteng Province, South Africa. Three different baits were offered: commercial fishmeal polymer, pieces of red meat and chicken heads. Bait uptake was observed using camera traps and patterns of uptake assessed by multiple correspondence analysis and Cox proportional hazards models. In general, all the baits were well accepted with an uptake of 91%. Median consumption time of bait for jackal was 18â¯h (IQR: 8-21â¯hours; range 7-66â¯hours) and for all other species it was 21â¯h (IQR: 4-44, range 1-283). In species other than jackals there was a faster uptake in the winter months when less food was available, and the vegetation was sparse, whereas jackal showed no seasonal preference. Jackal consumed 20% of baits placed and took all three bait types but showed a clear preference for chicken heads if available (Hazard ratio (HR)â¯=â¯3.41; 95%CI: 1.16-9.99; pâ¯=â¯0.025). Species other than carnivores preferred fishmeal polymer or red meat. Jackals showed no preference for time of day whereas herbivores and other species clearly preferred day; other carnivores preferred either day or night but not both, depending upon species. This study showed that chicken heads may be the preferred bait type for oral vaccination of black-backed jackal in this area, and that consideration should be given to placing bait during summer and at dusk, in order to minimize uptake by non-target species.
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Vacunas Antirrábicas/administración & dosificación , Vacunación/veterinaria , Animales , Animales Salvajes , Chacales , Vacunas Antirrábicas/efectos adversos , Sudáfrica , Vacunación/métodosRESUMEN
Three different noise moments of field strength, intensity, and their correlations are simultaneously measured. For this purpose a homodyne cross-correlation measurement [1] is implemented by superimposing the signal field and a weak local oscillator on an unbalanced beam splitter. The relevant information is obtained via the intensity noise correlation of the output modes. Detection details like quantum efficiencies or uncorrelated dark noise are meaningless for our technique. Yet unknown insight in the quantumness of a squeezed signal field is retrieved from the anomalous moment, correlating field strength with intensity noise. A classical inequality including this moment is violated for almost all signal phases. Precognition on quantum theory is superfluous, as our analysis is solely based on classical physics.
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A method is introduced that allows one to measure normal-ordered moments of the displaced photon-number operator up to higher orders, without the need of photon-number resolving detectors. It is based on unbalanced homodyne correlation measurements, with the local oscillator being replaced by a displaced dephased laser. The measured moments yield a simple approximation of quasiprobabilities, representing the full quantum state. Quantum properties of light are efficiently certified through normal-ordered observables directly accessible by our method, which is illustrated for a weakly squeezed vacuum and a single-photon-added thermal state.
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Retrotransposons are abundant in the genomes of plants. In the present study, inter-retrotransposon amplified polymorphism (IRAP) and retrotransposon-microsatellite amplified polymorphism (REMAP) markers were developed for the cassava genome (Manihot esculenta Crantz). Four cassava cultivars (Fécula Branca, IPR-União, Olho Junto, and Tamboara, two samples per cultivar) were used to obtain IRAP and REMAP fingerprints. Twelve designed primers were amplified alone and in combinations. The 42 IRAP/REMAP primer combinations amplified 431 DNA segments (bands; markers) of which 36 (8.36%) were polymorphic. The largest number of informative markers (16) was detected using the primers AYF2 and AYF2xAYF4. The number of bands for each primer varied from 3 to 16, with an average of 10.26 amplified segments per primer. The size of the amplified products ranged between 100 and 7000 bp. The AYF2 primer generated the highest number of amplified segments and showed the highest number of polymorphic bands (68.75%). Two samples of each cassava cultivar were used to illustrate the usefulness and the polymorphism of IRAP/REMAP markers. IRAP and REMAP markers produced a high number of reproducible bands, and might be informative and reliable for investigation of genetic diversity and relationships among cassava cultivars.
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Manihot/genética , Repeticiones de Microsatélite , Polimorfismo Genético , Retroelementos , Marcadores GenéticosRESUMEN
In endangered and local pig breeds of small population sizes, production has to focus on alternative niche markets with an emphasis on specific product and meat quality traits to achieve economic competiveness. For designing breeding strategies on meat quality, an adequate performance testing scheme focussing on phenotyped selection candidates is required. For the endangered German pig breed 'Bunte Bentheimer' (BB), no breeding program has been designed until now, and no performance testing scheme has been implemented. For local breeds, mainly reared in small-scale production systems, a performance test based on in vivo indicator traits might be a promising alternative in order to increase genetic gain for meat quality traits. Hence, the main objective of this study was to design and evaluate breeding strategies for the improvement of meat quality within the BB breed using in vivo indicator traits and genetic markers. The in vivo indicator trait was backfat thickness measured by ultrasound (BFiv), and genetic markers were allele variants at the ryanodine receptor 1 (RYR1) locus. In total, 1116 records of production and meat quality traits were collected, including 613 in vivo ultrasound measurements and 713 carcass and meat quality records. Additionally, 700 pigs were genotyped at the RYR1 locus. Data were used (1) to estimate genetic (co)variance components for production and meat quality traits, (2) to estimate allele substitution effects at the RYR1 locus using a selective genotyping approach and (3) to evaluate breeding strategies on meat quality by combining results from quantitative-genetic and molecular-genetic approaches. Heritability for the production trait BFiv was 0.27, and 0.48 for backfat thickness measured on carcass. Estimated heritabilities for meat quality traits ranged from 0.14 for meat brightness to 0.78 for the intramuscular fat content (IMF). Genetic correlations between BFiv and IMF were higher than estimates based on carcass backfat measurements (0.39 v. 0.25). The presence of the unfavorable n allele was associated with increased electric conductivity, paler meat and higher drip loss. The allele substitution effect on IMF was unfavorable, indicating lower IMF when the n allele is present. A breeding strategy including the phenotype (BFiv) combined with genetic marker information at the RYR1 locus from the selection candidate, resulted in a 20% increase in accuracy and selection response when compared with a breeding strategy without genetic marker information.
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Especies en Peligro de Extinción , Variación Genética , Genotipo , Carne/análisis , Carne/normas , Fenotipo , Sus scrofa/fisiología , Alelos , Animales , Cruzamiento , Especificidad de la Especie , Sus scrofa/genéticaRESUMEN
We present magnetic FePt nanoparticles with a hydrophilic, inert, and biocompatible silico-tungsten oxide shell. The particles can be functionalized, optically detected, and optically manipulated. To show the functionalization the fluorescent dye NOPS was bound to the FePt core-shell nanoparticles with propyl-triethoxy-silane linkers and fluorescence of the labeled particles were observed in ethanol (EtOH). In aqueous dispersion the NOPS fluorescence is quenched making them invisible using 1-photon excitation. However, we observe bright luminescence of labeled and even unlabeled magnetic core-shell nanoparticles with multi-photon excitation. Luminescence can be detected in the near ultraviolet and the full visible spectral range by near infrared multi-photon excitation. For optical manipulation, we were able to drag clusters of particles, and maybe also single particles, by a focused laser beam that acts as optical tweezers by inducing an electric dipole in the insulated metal nanoparticles. In a first application, we show that the luminescence of the core-shell nanoparticles is bright enough for in vivo multi-photon imaging in the mouse neocortex down to cortical layer 5.
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A 1.5-year-old neutered male rabbit was presented with chronic nasal discharge and ataxia. Rapid progression of neurological signs was noted subsequent to general anaesthesia and the rabbit was humanely destroyed due to the poor prognosis. At necropsy examination there were no gross changes affecting the brain or spinal cord. Microscopical examination revealed that the perikarya of numerous neurons in the brain and spinal cord were distended by the intracytoplasmic accumulation of pale, finely granular to vacuolar material. Transmission electron microscopy showed this to be composed of concentric membranous cytoplasmic bodies. Thin layer chromatography revealed elevation of GM2 ganglioside in the brain of this rabbit compared with that of an unaffected control rabbit. Enzymatically, there was markedly reduced activity of tissue ß-hexosaminidase A in brain and liver tissue from the rabbit. This was a result of an almost complete absence of the enzymatic activity of the α-subunit of that enzyme. These findings are consistent with sphingolipidosis comparable with human GM2 gangliosidosis variant B1.
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Gangliosidosis GM2/metabolismo , Gangliosidosis GM2/veterinaria , Neuronas/metabolismo , Conejos , Animales , Encéfalo/metabolismo , Encéfalo/patología , Gangliosidosis GM2/diagnóstico , Gangliosidosis GM2/patología , Cuerpos de Inclusión/ultraestructura , Masculino , Neuronas/patología , Vacuolas/ultraestructura , Cadena alfa de beta-Hexosaminidasa/metabolismoRESUMEN
OBJECTIVES: The study was intended to determine whether tocilizumab has a threshold pharmacologic effect on cardiac repolarization as detected by QT/QTc prolongation on 12-lead electrocardiograms (ECGs) in healthy subjects. METHODS: This was a multicenter, double-blind, placebo- and active-controlled, parallel group study. Healthy subjects received either an intravenous infusion of tocilizumab 10 mg/kg (n = 30) or 20 mg/kg (n = 31), oral moxifloxacin 400 mg (n = 31), or placebo (n = 29). Triplicate ECGs were obtained at predose, 2 h postdose on Day 1, and on Days 8, 15, and 29. Blood samples for pharmacokinetic analyses were collected at predose and up to 28 days postdose. Adverse events and laboratory safety tests were assessed throughout the study. RESULTS: Estimated mean study-specific, heart rate-corrected QT interval change from time-matched baseline versus placebo was negative at all time points (range -5.4 to -1.0 ms); the associated upper bound of the 1-sided 95% confidence limit was below threshold (10 ms). No clinically significant abnormalities in other electrocardiographic parameters were detected. No electrocardiographic abnormalities constituted an adverse event. After tocilizumab dosing, median time to maximum serum concentration was 2 h postdose; mean apparent terminal half-life was 9.3 ± 1.2 (10 mg/kg) and 12.1 ± 1.5 (20 mg/kg) days. Tocilizumab was well tolerated. Neutrophil counts decreased after tocilizumab administration, reaching a nadir 2 to 5 days after infusion. Mean neutrophil counts returned to baseline in the 10-mg/kg group and were near baseline in the 20-mg/kg group at the follow-up visit (Day 50 ± 2). CONCLUSIONS: There was no QT prolongation effect of clinical concern by tocilizumab at both the therapeutic (10 mg/kg) and the supratherapeutic (20 mg/kg) dose in healthy subjects.
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Anticuerpos Monoclonales Humanizados/farmacología , Electrocardiografía/efectos de los fármacos , Adolescente , Adulto , Anticuerpos Monoclonales Humanizados/efectos adversos , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
In rheumatoid arthritis (RA), interleukin-6 (IL-6) concentration is elevated, which may cause reduced cytochrome P450 (CYP) activity and increased exposure (peak plasma concentration and area under the plasma concentration-vs.-time curve (AUC)) to certain drugs. Tocilizumab may reverse IL-6-induced suppression of CYP3A4 activity. In this study, exposure to simvastatin was significantly reduced at 1 and 5 weeks after tocilizumab infusion in 12 patients with RA. The mean effect ratio for simvastatin AUC(last) was 43% (90% confidence interval (CI), 34-55%) at 1 week after tocilizumab infusion (day 15) and 61% (90% CI, 47-78%) at 5 weeks after tocilizumab infusion, as compared with baseline (day 1); both ratios were significantly lower than the bioequivalence boundary (80-125%). Mean plasma C-reactive protein (CRP) levels normalized within 1 week after tocilizumab was initiated; the time course of tocilizumab's CRP-reducing effect paralleled that of simvastatin pharmacokinetics. The study findings suggest that caution should be exercised when starting tocilizumab in RA patients who are taking simvastatin.
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Anticuerpos Monoclonales/sangre , Antirreumáticos/sangre , Artritis Reumatoide/sangre , Artritis Reumatoide/tratamiento farmacológico , Simvastatina/sangre , Adulto , Anciano , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados , Antirreumáticos/uso terapéutico , Interacciones Farmacológicas/fisiología , Femenino , Humanos , Interleucina-6/sangre , Masculino , Persona de Mediana Edad , Simvastatina/uso terapéuticoRESUMEN
Structure-guided lead optimization of recently described benzimidazolyl acetamides addressed the key liabilities of the previous lead compound 1. These efforts culminated in the discovery of 4-{(S)-2-[2-(4-chloro-phenyl)-5,6-difluoro-benzoimidazol-1-yl]-2-cyclohexyl-acetylamino}-3-fluoro-benzoic acid 7g, a highly potent and selective FXR agonist with excellent physicochemical and ADME properties and potent lipid lowering activity after oral administration to LDL receptor deficient mice.
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Bencimidazoles/química , Receptores Citoplasmáticos y Nucleares/agonistas , para-Aminobenzoatos , Ácido 4-Aminobenzoico/síntesis química , Ácido 4-Aminobenzoico/química , Ácido 4-Aminobenzoico/farmacocinética , Administración Oral , Animales , Bencimidazoles/síntesis química , Bencimidazoles/farmacocinética , Sitios de Unión , Simulación por Computador , Cristalografía por Rayos X , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Microsomas Hepáticos/metabolismo , Conformación Molecular , Ratas , Ratas Wistar , Receptores Citoplasmáticos y Nucleares/metabolismo , Receptores de LDL/deficiencia , Receptores de LDL/genética , Receptores de LDL/metabolismo , Relación Estructura-ActividadRESUMEN
Conventional methods of imaging membrane potential changes have limited spatial resolution, particularly along the axis perpendicular to the cortical surface. The laminar organization of the cortex suggests, however, that the distribution of activity in depth is not uniform. We developed a technique to resolve network activity of different cortical layers in vivo using two-photon microscopy of the voltage-sensitive dye (VSD) ANNINE-6. We imaged spontaneous voltage changes in the barrel field of the somatosensory cortex of head-restrained mice and analyzed their spatiotemporal correlations during anesthesia and wakefulness. EEG recordings always correlated more strongly with VSD signals in layer (L) 2 than in L1. Nearby (<200 mum) cortical areas were correlated with one another during anesthesia. Waking the mouse strongly desynchronized neighboring cortical areas in L1 in the 4- to 10-Hz frequency band. Wakefulness also slightly increased synchrony of neighboring territories in L2 in the 0.5- to 4.0-Hz range. Our observations are consistent with the idea that, in the awake animal, long-range inputs to L1 of the sensory cortex from various cortical and thalamic areas exert top-down control on sensory processing.
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Potenciales Evocados Somatosensoriales , Células Piramidales/fisiología , Corteza Somatosensorial/fisiología , Vigilia , Animales , Electroencefalografía , Colorantes Fluorescentes/análisis , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente/métodos , Fotones , Células Piramidales/citología , Corteza Somatosensorial/citologíaRESUMEN
The objective of this study was to determine the contemporary etiologies, treatment, and outcomes of moderate and large pericardial effusions in pediatric patients. We reviewed pediatric patients with moderate or large effusions diagnosed at Children's Hospital Boston. Effusion size was determined in offline review of echocardiograms. One hundred sixteen patients with moderate or large pericardial effusions were identified. The age range was 1 day to 17.8 years (median 8.6). The size of the pericardial effusions ranged from 0.5 to 4.7 cm (median 2.1). Neoplastic disease was present in 39% of patients, collagen vascular disease in 9%, renal disease in 8%, bacterial infection in 3%, and human immunodeficiency virus (HIV) in 2%; 37% were idiopathic. Pericardial drainage procedures were performed in 47 patients (41%). Of these, 29 (63%) had recurrent effusions leading to repeat drainage in 12 (41%). Pericardial effusions resolved within 3 months in 83% of patients who underwent drainage and in 91% of patients who did not. In summary, pediatric pericardial effusions were rarely caused by bacterial infections in this study population and were more frequently idiopathic or associated with neoplastic disease. Pericardial effusions often reaccumulated after drainage. The majority of both drained and undrained effusions resolved within 3 months.
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Derrame Pericárdico/etiología , Derrame Pericárdico/terapia , Adolescente , Niño , Preescolar , Enfermedades del Colágeno/complicaciones , Drenaje , Femenino , Humanos , Lactante , Recién Nacido , Modelos Logísticos , Masculino , Neoplasias/complicaciones , Recurrencia , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Staphylococcal cassette chromosome mec (SCCmec) type IV methicillin-resistant Staphylococcus aureus (MRSA) strains were identified in 8 (19.5%) of 41 consecutive patients with MRSA ventilator-associated pneumonia (VAP) in this retrospective, observational study. There were no significant differences in VAP severity and crude mortality rates between patients with SCCmec type II strains and patients with SCCmec type IV strains.
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Genes Bacterianos , Resistencia a la Meticilina/genética , Neumonía Asociada al Ventilador/microbiología , Infecciones Estafilocócicas/genética , Staphylococcus aureus/genética , Adulto , Anciano , Enfermedades Transmisibles Emergentes/genética , Enfermedades Transmisibles Emergentes/microbiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Philadelphia/epidemiología , Neumonía Asociada al Ventilador/genética , Neumonía Asociada al Ventilador/mortalidad , Reacción en Cadena de la Polimerasa , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/mortalidad , Staphylococcus aureus/efectos de los fármacosRESUMEN
Film formation and capillary condensation of nitrogen at 78 K on the mesoporous controlled pore glass CPG-10-75 have been studied at certain relative pressures by in situ small-angle neutron scattering. On desorption ramified clusters of vapor filled voids have been observed, but not on adsorption. The kinetics of adsorption and desorption have been followed. The experimental results are discussed with respect to recent theoretical studies of fluids in complex pore systems.
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Recombinant human erythropoietin (rhEPO) is used to treat anemia in chronic renal insufficiency. Erythropoietin (EPO) immunogenicity can lead to EPO-resistant anemia. Conjugating proteins with polyethylene glycol (PEG) can prolong elimination half-life and diminish protein immunogenicity. We investigated the efficacy of new erythropoietic agents, synthesized by single (Ro 50-3821) and multiple (MIX) integrations of PEG and succinimidyl butanoic acid with rhEPO, in rats with chronic renal insufficiency. Sprague-Dawley rats with surgically induced renal insufficiency received Ro 50-3821 or MIX subcutaneously (s.c.) over 4-12 weeks compared to rhEPO and NaCl. Hemoglobin and antibody levels served as primary efficacy and safety variables. Dosing intervals and dose-response characteristics were investigated. Ro 50-3821 (2.5 microg/kg once weekly) increased hemoglobin levels by 7 g/dl after 4 weeks compared to 1 g/dl in NaCl controls (P<0.05). MIX (2.5 microg/kg once weekly) and rhEPO (0.25 microg/kg three times weekly) increased hemoglobin levels by 3 g/dl. Ro 50-3821 administered for 12 weeks (0.75 microg/kg once weekly) increased hemoglobin levels (from 13 to 19 g/dl) more effectively than rhEPO (0.75 microg/kg once weekly, decline from 13 to 11 g/dl, P<0.05). No antibodies against Ro 50-3821 were detected after 12 weeks of treatment. Antibodies against rhEPO were seen in 69% of animals (P<0.00001). Ro 50-3821 increased hemoglobin levels with once weekly s.c. dosing. Multiple pegylated EPO is less effective. In rats, rhEPO failed to increase hemoglobin levels with once weekly long-term dosing. Antibody formation following rhEPO may explain this finding. Therefore, Ro 50-3821 may provide important clinical advantages compared to unpegylated EPO. It can be administered in longer dosing intervals and has a lower risk of unfavorable immunological responses.
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Eritropoyesis/efectos de los fármacos , Eritropoyetina/uso terapéutico , Fallo Renal Crónico/tratamiento farmacológico , Polietilenglicoles/uso terapéutico , Animales , Eritropoyetina/inmunología , Eritropoyetina/toxicidad , Hemoglobinas/análisis , Masculino , Polietilenglicoles/toxicidad , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes , Sístole/efectos de los fármacosRESUMEN
An evolutionary optimization technique is used to reconstruct digitized material models of 300(3) nm3 size for mesoporous two-phase systems. The models are adapted to the two-point probability (TPP) and to a volume-based pore-size distribution (PSD) which were derived from SANS and adsorption experiments and which carry statistical information about morphology and topology of the pore system. To avoid extreme update-costs, the bulk of mutations are assessed by means of a suitable approximation of the PSD; it is demonstrated that a sporadic insertion of the PSD suffices to drive the algorithm towards satisfactory models in acceptable time. Our approach is knowledge-based in the sense that (i) the mutations are restricted to expedient exchanges of phase-voxels by a heuristic rule, and (ii) the sporadic calculation of the PSD from the current state of the model, in essence, provides an efficient self-control for the evolutionary process. We applied the method to reconstruct periodic models of the xerogel Gelsil 200. Such reconstructs of real mesoporous solids could be utilized, for instance, to verify theories of adsorption and capillary condensation.
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PURPOSE: Although computer- and image-guided surgical procedures are an improvement of frame-guided stereotaxy, many navigation systems still require rigid fixation of the patient's head throughout the operation. This study describes the clinical application of a technical modification that enables cranial navigation with "free head mobility" using CT and MR images as well as the calculated 3-D reconstruction models. MATERIAL AND METHODS: A sensor-based electromagnetic neuronavigation system was expanded to allow the localization and position monitoring of several sensors within an electromagnetic field. One of these sensors was attached to a dental splint as an additional reference (DRF = dynamic reference frame). Thus, it was possible to determine the position of the sensor-guiding surgical instruments and to record the slightest movement of the cranium as well. This information was then used to continuously adapt the position of the imaging plane and the resultant calculated 3-D reconstructions to the actual position of the cranium. RESULTS: The clinical application of the DRF was tested for different neurosurgical procedures. They included image-guided biopsies and endoscopic interventions using MRI data, transnasal accesses to the base of the skull using CT data and surgical removal of multilocular metastases using data from both imaging modalities. Intracranial target reference points as well as those on the skull were found with a high accuracy to the initial measurement position after arbitrary movement of the patient's head. Thus, navigation was also possible without rigid fixation of the head because of the continuous adaptation of the imaging data on the change in position of the patient's head. CONCLUSION: Based on these first test results, a high clinical potential for DRF application in cranial navigation is to be expected. The aim of DRF is to dispense with the rigid fixation of the patient's head. This increases the application scope of image-guided navigation procedures to include, for example, any bioptic or endoscopic intervention, in which rigid pin fixation of the cranium is not required or desired. For all other procedures, continuous position monitoring by DRF ensures automatic correction of imaging data with mechanical alteration of the head position.
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Encefalopatías/cirugía , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Técnicas Estereotáxicas/instrumentación , Técnica de Sustracción , Cirugía Asistida por Computador/instrumentación , Tomografía Computarizada por Rayos X/métodos , Encefalopatías/diagnóstico , Diseño de Equipo , Análisis de Falla de Equipo , Cabeza/diagnóstico por imagen , Cabeza/patología , Cabeza/cirugía , Humanos , Imagenología Tridimensional/métodos , Inmovilización , Movimiento , Cráneo/diagnóstico por imagen , Cráneo/patología , Cráneo/cirugía , Cirugía Asistida por Computador/métodosRESUMEN
Heart failure from myocarditis may be transient or may progress to unremitting severe cardiac failure. This study was performed to determine the outcomes and prognostic features of pediatric patients with myocarditis. Patients with the diagnosis of myocarditis between 1990 and 2001 were identified through the coding system of Yale-New Haven Hospital. A total of 28 patients were included, with ages ranging from 1 day to 20 years. Before discharge, 11 patients developed unremitting severe cardiac failure. Of the remaining 17 patients, at the time of discharge 10 had normal systolic function and 7 had decreased systolic function. Unremitting cardiac failure developed in 9 of 14 patients (64%) with an ejection fraction < 30% and in only 2 of 14 (14%) of those with an ejection fraction > or = 30% on admission (p < 0.01). Furthermore, shortening fraction < 15%, left ventricular dilatation, and moderate to severe mitral regurgitation on admission as well as arrhythmia were significantly associated with development of unremitting severe cardiac failure. In this series of patients with myocarditis, by the time of discharge 39% of the patients had developed unremitting severe cardiac failure, 25% had depressed systolic function, and 36% had normal systolic function. Predictive factors at admission for poor outcome were ejection fraction < 30%, shortening fraction < 15%, left ventricular dilatation, and moderate to severe mitral regurgitation.