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1.
Background A high Mandard score implies a non-response to chemotherapy in oesophageal adenocarcinoma. However, some patients exhibit tumour volume reduction and a nodal response despite a high score. This study examines survival and recurrence patterns in these patients.Methods Clinicopathological factors were analysed using multivariable Cox regression assessing time to death and recurrence. Computed tomography-estimated tumour volume change was examined in a subgroup of consecutive patients.Results Five hundred and fifty-five patients were included. Median survival was 55 months (Mandard 1–3) and 21 months (Mandard 4 and 5). In the Mandard 4 and 5 group (332 patients), comparison between complete nodal responders and persistent nodal disease showed improved survival (90 vs 18 months), recurrence rates (locoregional 14.75 vs 28.74%, systemic 24.59 vs 48.42%) and circumferential resection margin positivity (22.95 vs 68.11%). Complete nodal response independently predicted improved survival (hazard ratio 0.34 (0.16–0.74). Post-chemotherapy tumour volume reduction was greater in patients with a complete nodal response (−16.3 vs −7.7 cm3, p = 0.033) with no significant difference between Mandard groups.Conclusion Patients with a complete nodal response to chemotherapy have significantly improved outcomes despite a poor Mandard score. High Mandard score does not correspond with a non-response to chemotherapy in all cases and patients with nodal downstaging may still benefit from adjuvant chemotherapy.Subject terms: Oesophageal cancer, Surgical oncology  相似文献   
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Abstract: Establishment of mixed bone marrow chimerism in pig-to-primate transplantation, as a means of inducing specific immune tolerance, will require that both immune and nonimmune barriers be overcome. As a preliminary step in evaluating nonimmune barriers in this system, we have developed an in vitro model of engraftment in which long-term culture of porcine bone marrow-derived hematopoietic cells is supported on preformed primate bone marrow stromal layers. In the absence of cytokine supplementation, primate stromal cells were unable to support long-term porcine hematopoiesis in these cultures. Supplementation with porcine Steel Factor was required for long-term maintenance of hematopoietic progenitor cell content and total hematopoietic activity. Addition of porcine IL-3, in combination with porcine Steel Factor, increased long-term progenitor cell content and hematopoietic activity on primate stroma to levels comparable to that obtained in cultures on porcine stroma. The combination of porcine GM-CSF and Steel Factor increased progenitor cell content and hematopoietic activity early in the cultures, but had little effect in long-term cultures. The Steel Factor and IL-3 combination was species-specific in its action in these cultures, as the corresponding human cytokines were unable to effectively support long-term porcine hematopoiesis. Likewise, the combination of porcine cytokines had only minimal effects on long-term bone marrow culture of primate CD34+ cells I on primate stroma.  相似文献   
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Mutations P225L and P225R were identified in codon 225 of the gene for ornithine transcarbamylase (OTC) in two patients with the neonatal form of OTC deficiency. The mutations occur at a CpG dinucleotide and eliminate a unique MspI restriction site in exon 7 of the OTC gene. They do not alter existing splice sites or create new sites, as judged from the nucleotide sequence. Both mutations are associated with undetectable levels of OTC antigen in liver homogenates, and with either complete lack of OTC activity (P225R mutation) or very small residual activity (0.15% of normal in the P225L mutation). The residual activity observed with P225L exhibits normal pH dependence, little or no increases in the Km values for ornithine and carbamoyl phosphate and normal stability at either 37°C or, in the presence of 0.66 mol/L urea, at 0°C. The latter conditions were used to examine whether the P225L mutation favours dissociation of the active OTC trimer. Given the normal stability and lack of tendency to dissociation of the mutant enzyme, it appears likely that the dramatic reduction in the level of OTC protein is due to inefficient conversion of the mutant OTC precursor polypeptide (pOTC) into the correctly localized, appropriately folded, mature enzyme trimer, suggesting degradation of pOTC in transit to the mitochondria.  相似文献   
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Mental health services for older adults benefit from an outreach approach that makes both clients and providers aware of the availability and usefulness of a range of programs to address various problems. Coordination of multiple systems of care is usually required to provide the necessary complement of services needed by older adults.  相似文献   
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Pericardial effusion complicating breast cancer.   总被引:2,自引:0,他引:2       下载免费PDF全文
Thirty-five patients with metastatic breast cancer and pericardial effusions are described. They were treated with specific endocrine or chemotherapy. Twenty-two (63%) had presented in cardiac tamponade and were rapidly relieved by pericardiocentesis. Eighteen (82%) of these required no further local treatment, 2 obtained relief from a second aspiration and 2 needed additional treatment (intrapericardial bleomycin instillation and surgical pleuropericardial window). The median survival was 13.2 months. No patient relapsed again in the pericardium, suggesting that their prognosis was that of the underlying disease. Cardiac tamponade should be considered in any breathless patient with malignancy. In breast cancer, periocardiocentesis is lifesaving and systemic treatment can usefully prolong life.  相似文献   
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Background: Reports of major and minor sequelae following lidocaine spinal anesthesia have generated interest in an alternative short-acting intrathecal agent. Of the available anesthetics suitable for short-duration spinal anesthesia, prilocaine is perhaps the most promising agent. However, data comparing the neurotoxicity of these agents are lacking. Accordingly, the present experiments investigate whether prilocaine and lidocaine differ with respect to sensory impairment and histologic damage when administered intrathecally in the rat.

Methods: Ninety rats were divided into three groups to receive an intrathecal infusion of 2.5% prilocaine in saline, 2.5% lidocaine in saline, or normal saline. The animals were assessed for persistent sensory impairment 4 days after anesthetic administration using the tail-flick test. Three days later, the animals were killed, and specimens of the spinal cord and nerve roots were obtained for histopathologic examination.

Results: Prilocaine and lidocaine produced equivalent elevations in tail-flick latency that differed significantly from saline. Histologic injury scores with prilocaine were greater than with lidocaine, but this difference did not reach statistical significance.  相似文献   

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Population-based association studies are powerful tools for the genetic mapping of complex diseases. However, this method is sensitive to potential confounding by population structure. While statistical methods that use genetic markers to detect and control for population structure have been the focus of current literature, the utility of self-defined race/ethnicity in controlling for population structure has been controversial. In this study of 1334 individuals, who self-identified as either African American, European American or Hispanic, we demonstrated that when the true underlying genetic structure and the self-defined racial/ethnic groups were roughly in agreement with each other, the self-defined race/ethnicity information was useful in the control of population structure.  相似文献   
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The cause of death.   总被引:2,自引:1,他引:1       下载免费PDF全文
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