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The behavioral relevance of neuronal activity in primate area MT for motion perception and control of visually guided eye movements is well documented. The projections of area MT comprise connections to subcortical structures and to the parietal network, both of which play a role in visuospatial transformation for guiding eyes and hands. Here, we have investigated, whether area MT is involved in the network needed to control visually guided arm movements. Our results show that half of the neurons tested significantly modulated their activity during visually guided arm movements. We conclude that the main reason for the neuronal modulation is not the arm movement per se, but the use of information from MT for visual feedback in the tracking movement. Moreover, control experiments show that attentional effects cannot solely cause the neuronal modulation. Thus, our study provides strong evidence that area MT is involved in processing visual information for visually guided manual tracking movements.  相似文献   
53.
Hay  CR; Laurian  Y; Verroust  F; Preston  FE; Kernoff  PB 《Blood》1990,76(5):882-886
Home therapy with porcine factor VIIIC was safe and effective when administered to five hemophilic patients over periods of 8 1/2, 6, 4, 3 1/2, and 2 years. No significant transfusion reactions occurred. Before treatment with porcine factor VIIIC, all five had high-level, high- responding anti-human VIIIC inhibitors initially lacking anti-porcine factor VIIIC activity. Although specific anti-porcine VIIIC inhibitors arose in all patients, these were generally transient, and only one patient became refractory to treatment. We believe that porcine factor VIIIC is the treatment of choice in patients whose inhibitors do not cross-react. All five patients lost their original anti-human VIIIC inhibitors after starting treatment with porcine VIIIC, permitting the reintroduction of human VIIIC in three of them. There has been no recurrence of anti-human VIIIC inhibitor activity during 2 to 3 years of regular treatment with human VIIIC in these patients. This suggests that tolerance to human VIIIC has arisen as a result of treatment with porcine VIIIC. Porcine VIIIC may have a role in the desensitization of some factor VIIIC inhibitor patients.  相似文献   
54.
Introduction: Cancer therapy has been transformed by the demonstration that tumor-specific T-cells can eliminate tumor cells in a clinical setting with minimal long-term toxicity. However, significant success in the treatment of leukemia and lymphoma with T-cells using native receptors or redirected with chimeric antigen receptors (CARs) has not been recapitulated in the treatment of solid tumors. This lack of success is likely related to the paucity of costimulatory and cytokine signaling available in solid tumors, in addition to a range of inhibitory mechanisms.

Areas covered: We summarize the latest developments in engineered T-cell immunotherapy, describe the limitations of these approaches in treating solid tumors, and finally highlight several strategies that may be useful in mediating solid tumor responses in the future, while also ensuring safety of engineered cells.

Expert opinion: CAR-T therapies require further engineering to achieve their potential against solid tumors. Facilitating cytokine signaling in CAR T-cells appears to be essential in achieving better responses. However, the engineering of T-cells with potentially unchecked proliferation and potency raises the question of whether the simultaneous combination of enhancements will prove safe, necessitating continued advancements in regulating CAR-T activity at the tumor site and methods to safely switch off these engineered cells.  相似文献   

55.

Introduction

Previous work has suggested that Emergency Department rotational patient assignment (a system in which patients are algorithmically assigned to physicians) is associated with immediate (first-year) improvements in operational metrics. We sought to determine if these improvements persisted over a longer follow-up period.

Methods

Single-site, retrospective analysis focused on years 2–4 post-implementation (follow-up) of a rotational patient assignment system. We compared operational data for these years with previously published data from the last year of physician self-assignment and the first year of rotational patient assignment. We report data for patient characteristics, departmental characteristics and facility characteristics, as well as outcomes of length of stay (LOS), arrival to provider time (APT), and rate of patients who left before being seen (LBBS).

Results

There were 140,673 patient visits during the five year period; 138,501 (98.7%) were eligible for analysis. LOS, APT, and LBBS during follow-up remained improved vs. physician self-assignment, with improvements similar to those noted in the first year of implementation. Compared with the last year of physician self-assignment, approximate yearly average improvements during follow-up were a decrease in median LOS of 18 min (8% improvement), a decrease in median APT of 21 min (54% improvement), and a decrease in LBBS of 0.69% (72% improvement).

Conclusion

In a single facility study, rotational patient assignment was associated with sustained operational improvements several years after implementation. These findings provide further evidence that rotational patient assignment is a viable strategy in front-end process redesign.  相似文献   
56.
IgG4-related disease is a newly recognized fibro-inflammatory condition. The purpose of this report is to present a patient with 11 years of follow-up, who revealed characteristic features of IgG4-related disease with systemic, orbital and corneal involvement and showed a favorable response to steroids and rituximab treatment.  相似文献   
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Background

The Heartmate 3 (HM3) is a Conformiteé Européenne mark–approved left ventricular (LV) assist device (LVAD) with fully magnetically levitated rotor and features consisting of a wide range operational speeds, wide flow paths, and artificial pulse. We performed a hemodynamic-echocardiographic speed optimization evaluation in HM3-implanted patients to achieve optimal LV- and right ventricular (RV) shape.

Methods and Results

Sixteen HM3 patients underwent pump speed ramp tests with right heart catheterization. Three-dimensional echocardiographic (3DE) LV and RV datasets (Philips) were acquired, and volumetric (Tomtec) and shape (custom software) analyses were performed (LV: sphericity, conicity; RV: septal and free-wall curvatures). Data were recorded at up to 13 speed settings. Speed changes were in 100-rpm steps, starting at 4600 rpm and ramping up to 6200 rpm. 3DE was feasible in 50% of the patients. Mean original speed was 5306 ± 148 rpm. LV end-diastolic (ED) diameter (?0.15 ± 0.09 cm/100 rpm) and volumes (ED: 269 ± 109 mL to 175 ± 90 mL; end-systolic [ES]: 234 ± 111 mL to 146 ± 81 mL) progressively decreased as the shape became less spherical and more conical; RV volumes initially remained stable, but at higher speeds increased (ED: from 148 ± 64 mL to 181 ± 92 mL; ES: 113 ± 63 mL to 130 ± 69 mL). On average, the RV septum became less convex (bulging toward the LV) at the highest speeds.

Conclusions

LV and RV shape changes were noted in HM3-supported patients. Although a LV volumetric decrease and shape improvement was consistently noted, RV volumes grew in response to increase in speed above a certain point. A next concern would be whether understanding of morphologic and function changes in LV and RV during LVAD speed change assessed with the use of 3DE helps to optimize LVAD speed settings and improve clinical outcomes.  相似文献   
60.
The alkylation of chromatin constituents (DNA, histones and non-histones) in liver cell nuclei was investigated at various times after intraperitoneal injection of rats with 3H-cyclophosphamid. The highest alkylation was found in the DNA, the lowest in the histones; the euchromatic portions were alkylated several times higher compared to those of the heterochromatin. The eventual elimination of 3H-activity with time indicates that cyclophosphamid leads to repair processes in the DNA, this conclusion being supported by other experimental observations. In some of the 16 subfractions of the nonhistone proteins, alkylated portions are apparantly eliminated by normal protein turnover; however, in other nonhistones this elimination is inhibited, whereby in one subfraction it seems to be accelerated. The results of analog experiments with 14C-tryptophan as a precursor for nonhistone protein synthesis serve as a reference for this. In supplementary in-vitro model experiments using triaziquon as an alkylating agent indications for DNA-Protein-cross-links in chromatin could be obtained by the technique of X-ray low angle scattering, and according to sedimentation behaviour.  相似文献   
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