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The purpose of this retrospective study was to assess the efficacy of salvage radiation therapy (RT) or chemoradiation therapy (CRT) for locoregional recurrence (LR) of esophageal cancer after curative surgery. Forty‐two patients who received salvage RT or CRT for LR of esophageal cancer after curative surgery between November 2000 and May 2012 were reviewed. The intended RT regimen was 60 Gy in 30 fractions combined with concurrent platinum‐based chemotherapy. Median follow‐up periods were 17.9 months for all evaluable patients and 28.2 months for patients still alive (19 patients) at analysis time. The 1‐, 2‐, and 3‐year survival rates were 81.2 ± 6.4%, 51.3 ± 8.6%, and 41.1 ± 8.7%, respectively, with a median survival time of 24.3 ± 4.1 months. Out of 41 evaluable patients, 16 patients (39%) were alive beyond 2 years from salvage therapy. However, univariate analyses for overall survival showed no significant prognostic factor. Grade 3 or higher leukocytopenia was observed in 46% of the patients. Salvage RT or CRT for LR after surgery for esophageal cancer was safe and effective. These therapies may offer long‐term survival to some patients. RT or CRT should be considered for LR.  相似文献   
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Objective

To compare the spatial distribution of motor units recruited in tibialis anterior (TA) when electrical stimulation is applied over the TA muscle belly versus the common peroneal nerve trunk.

Methods

Electromyography (EMG) was recorded from the surface and from fine wires in superficial and deep regions of TA. Separate M-wave recruitment curves were constructed for muscle belly and nerve trunk stimulation.

Results

During muscle belly stimulation, significantly more current was required to generate M-waves that were 5% of the maximal M-wave (Mmax; M5%max), 50% Mmax (M50%max) and 95% Mmax (M95%max) at the deep versus the superficial recording site. In contrast, during nerve trunk stimulation, there were no differences in the current required to reach M5%max, M50%max or M95%max between deep and superficial recording sites. Surface EMG reflected activity in both superficial and deep muscle regions.

Conclusions

Stimulation over the muscle belly recruited motor units from superficial to deep with increasing stimulation amplitude. Stimulation over the nerve trunk recruited superficial and deep motor units equally, regardless of stimulation amplitude.

Significance

These results support the idea that where electrical stimulation is applied markedly affects how contractions are produced and have implications for the interpretation of surface EMG data.  相似文献   
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OBJECTIVE: To clarify the signaling mechanism of human myeloid differentiation by hematopoietic growth factors and cytokines, we investigated the role of extracellular signal-regulated kinase (ERK) during the differentiation of human monoblastic U937 cells stimulated by granulocyte-macrophage colony-stimulating factor (GM-CSF) and tumor necrosis factor (TNF). MATERIALS AND METHODS: Myeloid differentiation was evaluated by morphology, function (respiratory burst activity), and cell surface expression of adhesion molecule (CD11b), and activation of ERK and/or p38 was determined by Western blotting and/or in vitro kinase assay. Inhibition of the ERK pathway was performed using PD98059, a specific inhibitor of this pathway. RESULTS: U937 cells were induced to be differentiated by the combination of GM-CSF and TNF, but only minimally by either cytokine alone. Transient phosphorylation and activation of ERK was induced by both GM-CSF alone and combination of the two cytokines, whereas sustained phosphorylation and activation was induced only by the combination. In addition, PD98059, a specific inhibitor of ERK pathway, almost completely abolished this prolonged phosphorylation of ERK and completely blocked differentiation. In contrast, both TNF alone and cytokine combination equivalently phosphorylated p38 in U937 cells, which was dissociated from differentiation, and a specific inhibitor of p38 (SB203580) did not inhibit differentiation. CONCLUSIONS: The results indicate potential roles of sustained activation of ERK but not of p38 in the signaling pathways for human myeloid differentiation in U937 cells synergistically stimulated by the two physiologic cytokines GM-CSF and TNF.  相似文献   
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BACKGROUND/AIMS: There are no systematic criteria for cervical lymphadenectomy in esophageal carcinoma. We provide a new algorithm for deciding whether to use three-field dissection or two-field dissection. METHODOLOGY: Ninety-eight patients underwent curative esophagectomies with three-field lymph node dissections for squamous cell carcinoma of the thoracic esophagus. We examined the outcomes and predictors for survival of these patients. Therefore, we devised a new decision tree for deciding whether to use three-field dissection or two-field dissection. RESULTS: The overall 5-year survival rate for the 98 patients was 41.3%. The number of positive nodes was the only significant predictor for survival in the multivariate Cox proportional hazard model. The outcomes of patients with positive supraclavicular/internal jugular nodes were poor. On the other hand, positive cervical paraesophageal nodes do not worsen prognosis. We provided a new algorithm for selecting procedure of lymphadenectomy based on the presence of lymph node metastases. This algorithm is decided by the number of positive nodes, the presence of cervical node metastasis and recurrent nerve node metastasis. According to this decision tree, there were a few patients who needed absolutely three-field dissections. CONCLUSIONS: The new algorithm may be helpful for deciding three-field dissection or two-field dissection for thoracic esophageal carcinoma.  相似文献   
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