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71.
Hodgkin lymphoma (HL) relapsing after allogeneic stem cell transplantation (alloSCT) presents a major clinical challenge. In the present investigation, we evaluated brentuximab vedotin, a CD30-directed Ab-drug conjugate, in 25 HL patients (median age, 32 years; range, 20-56) with recurrent disease after alloSCT (11 unrelated donors). Patients were > 100 days after alloSCT, had no active GVHD, and received a median of 9 (range, 5-19) prior regimens. Nineteen (76%) had refractory disease immediately before enrollment. Patients received 1.2 or 1.8 mg/kg of brentuximab vedotin IV every 3 weeks (median, 8 cycles; range, 1-16). Overall and complete response rates were 50% and 38%, respectively, among 24 evaluable patients. Median time to response was 8.1 weeks, median progression-free survival was 7.8 months, and the median overall survival was not reached. Cough, fatigue, and pyrexia (52% each), nausea and peripheral sensory neuropathy (48% each), and dyspnea (40%) were the most frequent adverse events. The most common adverse events ≥ grade 3 were neutropenia (24%), anemia (20%), thrombocytopenia (16%), and hyperglycemia (12%). Cytomegalovirus was detected in 5 patients (potentially clinically significant in 1). These results support the potential utility of brentuximab vedotin for selected patients with HL relapsing after alloSCT.  相似文献   
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Although recently the incidence of prehypertension has increased considerably, the pathophysiological mechanisms and the effects of gender in its causation have not yet been fully elucidated. Therefore, in this study body mass index (BMI), waist-hip ratio (WHR), basal heart rate (BHR), blood pressure (BP), rate pressure product (RPP), and spectral indices of heart rate variability (HRV) were reordered and analyzed in normotensive and prehypertensive males and females. It was observed that low frequency-high frequency (LF-HF) ratio, the sensitive indicator of sympathovagal imbalance (SVI), is significantly more (P < .001) in male prehypertensives compared with female prehypertensives. Although SVI in prehypertensives was found to be due to both sympathetic activation and vagal inhibition, contribution of vagal withdrawal was prominent in males. The LF-HF ratio was significantly correlated with BMI, WHR, BHR, BP, and RPP, which was more prominent in male prehypertensives and the degree of correlation was more for WHR and diastolic pressure. It was concluded that vagal inhibition plays an important role in critical alteration of SVI in the genesis of prehypertension, especially in males, and WHR could be a better indicator of SVI in prehypertensives. It was suggested that prehypertensives should improve their vagal tone to restore the sympathovagal homeostasis.  相似文献   
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Background:Presenting and demonstrating a surgical procedure in the current era is difficult without good intraoperative pictures and videos. A long, complex, multi-staged surgery is better illustrated by detailed intraoperative images at various stages. Although desirable, it may be difficult due to various reasons.Results:It is a simple technique with a moderate learning curve. Once familiar with technique, one can effectively use the technique to convey the details in much more clear manner.Conclusion:It is a simple and effective way of communicating through digital images, and gives the audience a 3 dimensional idea about the concept.KEY WORDS: Clay models in plasticine surgery, photography, presentations in plastic surgery, teaching and patient education, use of clay models for presentations  相似文献   
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Li B  Avinash GB  Hsieh J 《Medical physics》2007,34(10):3732-3738
Until recently, most studies addressing the trade-off between spatial resolution and quantum noise were performed in the context of single-slice CT. In this study, we extend the theoretical framework of previous works to volumetric CT and further extend it by taking into account the actual shapes of the preferred reconstruction kernels. In the experimental study, we also attempt to explore a three-dimensional approach for spatial resolution measurement, as opposed to the conventional two-dimensional approaches that were widely adopted in previously published studies. By scanning a finite-sized sphere phantom, the MTF was measured from the edge profile along the spherical surface. Cases of different resolutions (and noise levels) were generated by adjusting the reconstruction kernel. To reduce bias, the total photon fluxes were matched: 120 kVp, 200 mA, and 1 s per gantry rotation. All data sets were reconstructed using a modified FDK algorithm under the same condition: Scan field-of-view (SFOV) = 10 cm, and slice thickness = 0.625 mm. The theoretical analysis indicated that the variance of noise is proportional to > 4th power of the spatial resolution. Our experimental results supported this conclusion by showing the relationship is 4.6th (helical) or 5th (axial) power.  相似文献   
80.
Reference frames for reach planning in macaque dorsal premotor cortex   总被引:1,自引:0,他引:1  
When a human or animal reaches out to grasp an object, the brain rapidly computes a pattern of muscular contractions that can acquire the target. This computation involves a reference frame transformation because the target's position is initially available only in a visual reference frame, yet the required control signal is a set of commands to the musculature. One of the core brain areas involved in visually guided reaching is the dorsal aspect of the premotor cortex (PMd). Using chronically implanted electrode arrays in two Rhesus monkeys, we studied the contributions of PMd to the reference frame transformation for reaching. PMd neurons are influenced by the locations of reach targets relative to both the arm and the eyes. Some neurons encode reach goals using limb-centered reference frames, whereas others employ eye-centered reference fames. Some cells encode reach goals in a reference frame best described by the combined position of the eyes and hand. In addition to neurons like these where a reference frame could be identified, PMd also contains cells that are influenced by both the eye- and limb-centered locations of reach goals but for which a distinct reference frame could not be determined. We propose two interpretations for these neurons. First, they may encode reach goals using a reference frame we did not investigate, such as intrinsic reference frames. Second, they may not be adequately characterized by any reference frame.  相似文献   
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