954 resultados para Single-unit Responses


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Treatments for patients with hematologic malignancies not in remission are limited, but a few clinical studies have investigated the effects of salvaged unrelated cord blood transplantation (CBT). We retrospectively studied 19 patients with acute leukemia, 5 with myelodysplastic syndrome (MDS with refractory anemia with excess blasts [RAEB]), and 2 with non-Hodgkin's lymphoma who received 1 CBT unit ≤2 loci human leukocyte antigen (HLA)-mismatched after undergoing myeloablative conditioning regimens between July 2005 and July 2014. All of them were in non-remission before transplantation. The infused total nucleated cell (TNC) dose was 4.07 (range 2.76-6.02)×107/kg and that of CD34+ stem cells was 2.08 (range 0.99-8.65)×105/kg. All patients were engrafted with neutrophils that exceeded 0.5×109/L on median day +17 (range 14-37 days) and had platelet counts of >20×109/L on median day +35 (range 17-70 days). Sixteen patients (61.5%) experienced pre-engraftment syndrome (PES), and six (23.1%) patients progressed to acute graft-versus-host disease (GVHD). The cumulative incidence rates of II-IV acute GVHD and chronic GVHD were 50% and 26.9%, respectively. After a median follow-up of 27 months (range 5-74), 14 patients survived and 3 relapsed. The estimated 2-year overall survival (OS), disease-free survival (DFS), and non-relapse mortality (NRM) rates were 50.5%, 40.3%, and 35.2%, respectively. Salvaged CBT might be a promising modality for treating hematologic malignancies, even in patients with a high leukemia burden.

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We consider a version of the cooperative buyer-seller market game of Shapley and Shubik (1972). For this market we propose a c1ass of sealed- bid auctions where objects are sold simultaneously at a market c1earing price rule. We ana1yze the strategic games induced by these mechanisms under the complete information approach. We show that these noncooperative games can be regarded as a competitive process for achieving a cooperative outcome: every Nash equilibrium payoff is a core outcome of the cooperative market game. Precise answers can be given to the strategic questions raised.

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The theory of auctions of a single object generalizes to a situation where identical objects are sold either sequentially or simultaneously but individuais can only buy one object. In this context, I will present a survey of the main results regarding the ranking of auctions based on revenue, bidding behaviour, effects of entry fees and reserve prices, and other strategic issues.

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Objectives: Because the mechanical behavior of the implant-abutment system is critical for the longevity of implant-supported reconstructions, this study evaluated the fatigue reliability of different implant-abutment systems used as single-unit crowns and their failure modes. Methods and Materials: Sixty-three Ti-6Al-4V implants were divided in 3 groups: Replace Select (RS); IC-IMP Osseotite; and Unitite were restored with their respective abutments. Anatomically correct central incisor metal crowns were cemented and subjected to separate single load to failure tests and step-stress accelerated life testing (n = 18). A master Weibull curve and reliability for a mission of 50,000 cycles at 200 N were calculated. Polarized-light and scanning electron microscopes were used for failure analyses. Results: The load at failure mean values during step-stress accelerated life testing were 348.14 N for RS, 324.07 N for Osseotite, and 321.29 N for the Unitite systems. No differences in reliability levels were detected between systems, and only the RS system mechanical failures were shown to be accelerated by damage accumulation. Failure modes differed between systems. Conclusions: The 3 evaluated systems did not present significantly different reliability; however, failure modes were different. (Implant Dent 2012;21:67-71)

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AIM: To compare the 10-year peri-implant bone loss (BL) rate in periodontally compromised (PCP) and periodontally healthy patients (PHP) around two different implant systems supporting single-unit crowns. MATERIALS AND METHODS: In this retrospective, controlled study, the mean BL (mBL) rate around dental implants placed in four groups of 20 non-smokers was evaluated after a follow-up of 10 years. Two groups of patients treated for periodontitis (PCP) and two groups of PHP were created. For each category (PCP and PHP), two different types of implant had been selected. The mBL was calculated by subtracting the radiographic bone levels at the time of crown cementation from the bone levels at the 10-year follow-up. RESULTS: The mean age, mean full-mouth plaque and full-mouth bleeding scores and implant location were similar between the four groups. Implant survival rates ranged between 85% and 95%, without statistically significant differences (P>0.05) between groups. For both implant systems, PCP showed statistically significantly higher mBL rates and number of sites with BL> or =3 mm compared with PHP (P<0.0001). CONCLUSIONS: After 10 years, implants in PCP yielded lower survival rates and higher mean marginal BL rates compared with those of implants placed in PHP. These results were independent of the implant system used or the healing modality applied.

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To evaluate the clinical and radiographic changes at implants in posterior maxillary and mandibular areas supporting single-unit crowns (SCs) and fixed dental prostheses (FDPs) with one mesial or distal cantilever extension after an observation period of at least 3 years.

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OBJECTIVES The aim of this case series was to introduce a complete digital workflow for the production of monolithic implant crowns. MATERIAL AND METHODS Six patients were treated with implant-supported crowns made of resin nano ceramic (RNC). Starting with an intraoral optical scan (IOS), and following a CAD/CAM process, the monolithic crowns were bonded either to a novel prefabricated titanium abutment base (group A) or to a CAD/CAM-generated individualized titanium abutment (group B) in premolar or molar sites on a soft tissue level dental implant. Economic analyses included clinical and laboratory steps. An esthetic evaluation was performed to compare the two abutment-crown combinations. RESULTS None of the digitally constructed RNC crowns required any clinical adaptation. Overall mean work time calculations revealed obvious differences for group A (65.3 min) compared with group B (86.5 min). Esthetic analysis demonstrated a more favorable outcome for the prefabricated bonding bases. CONCLUSIONS Prefabricated or individualized abutments on monolithic RNC crowns using CAD/CAM technology in a model-free workflow seem to provide a feasible and streamlined treatment approach for single-edentulous space rehabilitation in the posterior region. However, RNC as full-contour material has to be considered experimental, and further large-scale clinical investigations with long-term follow-up observation are necessary.

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INTRODUCTION The Rondo is a single-unit cochlear implant (CI) audio processor comprising the identical components as its behind-the-ear predecessor, the Opus 2. An interchange of the Opus 2 with the Rondo leads to a shift of the microphone position toward the back of the head. This study aimed to investigate the influence of the Rondo wearing position on speech intelligibility in noise. METHODS Speech intelligibility in noise was measured in 4 spatial configurations with 12 experienced CI users using the German adaptive Oldenburg sentence test. A physical model and a numerical model were used to enable a comparison of the observations. RESULTS No statistically significant differences of the speech intelligibility were found in the situations in which the signal came from the front and the noise came from the frontal, ipsilateral, or contralateral side. The signal-to-noise ratio (SNR) was significantly better with the Opus 2 in the case with the noise presented from the back (4.4 dB, p < 0.001). The differences in the SNR were significantly worse with the Rondo processors placed further behind the ear than closer to the ear. CONCLUSION The study indicates that CI users with the receiver/stimulator implanted in positions further behind the ear are expected to have higher difficulties in noisy situations when wearing the single-unit audio processor.

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BACKGROUND The role of sentinel lymph node biopsy (SLNB) and its benefits in patients with thick melanoma is still controversial. OBJECTIVES We evaluated the clinical effect of SLNB in patients with thick melanoma. METHODS We performed a retrospective cohort review (1996-2012) of thick melanomas. Collected data included the patient and tumour characteristics. Locoregional recurrence, distant metastases, disease free and overall survival were compared between the patients with positive and negative SLNB. RESULTS 126 thick melanomas with a mean age of 64.09 years were included in the study. Positive SLNB were found in 47 (37.3%) patients. Significantly more locoregional recurrence (P = 0.002) and distant metastases (P = 0.030) were detected in the patients with positive SLNB. Furthermore, the patients with negative SLNB showed significantly better disease free survival (P = 0.021). CONCLUSIONS Positive SLNB might be prognostic factor in thick melanoma and aggravates the outcome of thick melanomas.

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We revisit the one-unit gradient ICA algorithm derived from the kurtosis function. By carefully studying properties of the stationary points of the discrete-time one-unit gradient ICA algorithm, with suitable condition on the learning rate, convergence can be proved. The condition on the learning rate helps alleviate the guesswork that accompanies the problem of choosing suitable learning rate in practical computation. These results may be useful to extract independent source signals on-line.

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Restricted cochlear lesions in adult animals result in plastic changes in the representation of the lesioned cochlea, and thus in the frequency map, in the contralateral auditory cortex and thalamus. To examine the contribution of subthalamic changes to this reorganization, the effects of unilateral mechanical cochlear lesions on the frequency organization of the central nucleus of the inferior colliculus (ICC) were examined in adult cats. Lesions typically resulted in a broad high-frequency hearing loss extending from a frequency in the range 15-22 kHz. After recovery periods of 2.5-18 months, the frequency organization of ICC contralateral to the lesioned cochlea was determined separately for the onset and late components of multiunit responses to tone-burst stimuli. For the late response component in all but one penetration through the ICC, and for the onset response component in more than half of the penetrations, changes in frequency organization in the lesion projection zone were explicable as the residue of prelesion responses. In half of the penetrations exhibiting nonresidue type changes in onset-response frequency organization, the changes appeared to reflect the unmasking of normally inhibited inputs. In the other half it was unclear whether the changes reflected unmasking or a dynamic process of reorganization. Thus, most of the observed changes were explicable as passive consequences of the lesion, and there was limited evidence for plasticity in the ICC. The implications of the data with respect to the primary locus of the changes and to the manner in which they contribute to thalamocortical reorganization are considered. (C) 2003 Wiley-Liss, Inc.

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Barrels are discrete cytoarchitectonic neurons cluster located in the layer IV of the somatosensory¦cortex in mice brain. Each barrel is related to a specific whisker located on the mouse snout. The¦whisker-to-barrel pathway is a part of the somatosensory system that is intensively used to explore¦sensory activation induced plasticity in the cerebral cortex.¦Different recording methods exist to explore the cortical response induced by whisker deflection in¦the cortex of anesthetized mice. In this work, we used a method called the Single-Unit Analysis by¦which we recorded the extracellular electric signals of a single barrel neuron using a microelectrode.¦After recording the signal was processed by discriminators to isolate specific neuronal shape (action¦potentials).¦The objective of this thesis was to familiarize with the barrel cortex recording during whisker¦deflection and its theoretical background and to compare two different ways of discriminating and¦sorting cortical signal, the Waveform Window Discriminator (WWD) or the Spike Shape Discriminator (SSD).¦WWD is an electric module allowing the selection of specific electric signal shape. A trigger and a¦window potential level are set manually. During measurements, every time the electric signal passes¦through the two levels a dot is generated on time line. It was the method used in previous¦extracellular recording study in the Département de Biologie Cellulaire et de Morphologie (DBCM) in¦Lausanne.¦SSD is a function provided by the signal analysis software Spike2 (Cambridge Electronic Design). The¦neuronal signal is discriminated by a complex algorithm allowing the creation of specific templates.¦Each of these templates is supposed to correspond to a cell response profile. The templates are saved¦as a number of points (62 in this study) and are set for each new cortical location. During¦measurements, every time the cortical recorded signal corresponds to a defined number of templates¦points (60% in this study) a dot is generated on time line. The advantage of the SSD is that multiple¦templates can be used during a single stimulation, allowing a simultaneous recording of multiple¦signals.¦It exists different ways to represent data after discrimination and sorting. The most commonly used¦in the Single-Unit Analysis of the barrel cortex are the representation of the time between stimulation¦and the first cell response (the latency), the representation of the Response Magnitude (RM) after¦whisker deflection corrected for spontaneous activity and the representation of the time distribution¦of neuronal spikes on time axis after whisker stimulation (Peri-Stimulus Time Histogram, PSTH).¦The results show that the RMs and the latencies in layer IV were significantly different between the¦WWD and the SSD discriminated signal. The temporal distribution of the latencies shows that the¦different values were included between 6 and 60ms with no peak value for SSD while the WWD¦data were all gathered around a peak of 11ms (corresponding to previous studies). The scattered¦distribution of the latencies recorded with the SSD did not correspond to a cell response.¦The SSD appears to be a powerful tool for signal sorting but we do not succeed to use it for the¦Single-Unit Analysis extracellular recordings. Further recordings with different SSD templates settings¦and larger sample size may help to show the utility of this tool in Single-Unit Analysis studies.

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Neuroimaging studies typically compare experimental conditions using average brain responses, thereby overlooking the stimulus-related information conveyed by distributed spatio-temporal patterns of single-trial responses. Here, we take advantage of this rich information at a single-trial level to decode stimulus-related signals in two event-related potential (ERP) studies. Our method models the statistical distribution of the voltage topographies with a Gaussian Mixture Model (GMM), which reduces the dataset to a number of representative voltage topographies. The degree of presence of these topographies across trials at specific latencies is then used to classify experimental conditions. We tested the algorithm using a cross-validation procedure in two independent EEG datasets. In the first ERP study, we classified left- versus right-hemifield checkerboard stimuli for upper and lower visual hemifields. In a second ERP study, when functional differences cannot be assumed, we classified initial versus repeated presentations of visual objects. With minimal a priori information, the GMM model provides neurophysiologically interpretable features - vis à vis voltage topographies - as well as dynamic information about brain function. This method can in principle be applied to any ERP dataset testing the functional relevance of specific time periods for stimulus processing, the predictability of subject's behavior and cognitive states, and the discrimination between healthy and clinical populations.