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121.
PURPOSE: Attempts to improve survival of patients with esophageal cancer have been made using induction chemoradiotherapy (CRT) followed by surgery. A large single-center experience was reviewed to determine which treatment-related variables could predict survival and recurrence. PATIENTS AND METHODS: All patients undergoing esophagectomy between January 1994 and December 2002 were reviewed. Univariate and multivariate analyses were performed using log-rank and Cox proportional hazards models, and survival curves were estimated using the Kaplan-Meier method. RESULTS: Of 171 patients with invasive cancer, 131 (77%) underwent preoperative CRT. The average age was 60 years, and most patients were male (85%). Operations performed included Ivor-Lewis (60%), transhiatal (8%), three-hole (23%), or left thoracoabdominal (8%) esophagectomy. Perioperative mortality rate was 5%. Median overall survival (OS) of the entire group was 33 months, and the 5-year OS rate was 26%. Induction CRT was associated with a 33% 5-year survival rate compared with 11% for surgery alone (P = .43). Patients downstaged to pathologic stage 0 or I had an improved OS and disease-free survival (DFS) compared with those patients who were not downstaged (P = .022). Additionally, the ability to perform an R0 resection was a significant factor for OS and DFS (n = 130; P < .0001 and P <.0002, respectively). CONCLUSION: Response to CRT and the ability to perform an R0 resection are associated with significantly improved survival in patients with esophageal carcinoma.  相似文献   
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Immunosuppressives have been used in multiple sclerosis (MS) since 1966. Today, we have many treatments for the relapsing forms of the disease, including 8 US Food and Drug Administration-approved therapies, with more soon to be introduced. Given the current treatment landscape what place do immunosuppressants have in combating MS? Trial work and our experience suggest that immunosuppressives still have an important role in treating MS. Cyclophosphamide finds use in treating patients with severe, inflammatory relapsing remitting MS or those suffering from a fulminant attack. We tend to employ mycophenolate mofetil as an add-on to injectable therapy for patients experiencing breakthrough activity. Some progressive (primary progressive multiple sclerosis or secondary progressive multiple sclerosis) patients may stabilize after treatment with either cyclophosphamide or mycophenolate. We rarely employ mitoxantrone because of potential cardiac or carcinogenic effects. We prefer to use cyclophosphamide or mycophenolate mofetil in preference to methotrexate because evidence of efficacy is limited for this drug. We have less experience with azathioprine, but it may be an alternative for patients with limited options who are unable to tolerate conventional therapies.  相似文献   
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Teeth adopt a variety of different morphologies, each of which is presumably optimized for performing specific functions during feeding. It is generally agreed that the enamel cap is a crucial element in controlling the mechanical behavior of mammalian teeth under load. Incisors are particularly interesting in terms of structure–function relations, as their role in feeding is that of the ‘first bite’. However, little is known how incisor cap morphology is related to tooth deformation. In the present paper we examine the mechanical behavior of mandibular central incisors in the cercopithecine primate Macaca mulatta under loads similar to those encountered during ingestion. We map three‐dimensional displacements on the labial surface of the crown as it is compressed, using electronic speckle pattern interferometry (ESPI), an optical metrology method. In addition, micro‐computed tomography is used to obtain data regarding the morphology of the enamel cap, which in the M. mulatta lower incisors exhibits missing or very little enamel on the lingual face. The results showed that although compressed along a longitudinal axis, deformation in the incisors mostly occurred in the lingual direction and orthogonal to the direction of the applied load. Both isolated, embedded teeth and teeth in the mandible showed considerable lingual deformation. Incisor deformation in the mandible was generally greater, reflecting the additional freedom of movement enabled by the supporting structures. We show that the association with adjacent teeth in the arch is significant for the behavior of the tooth under load. Finally, loading two teeth simultaneously in the mandible showed that they work as one functional unit. We suggest that these results demonstrate the importance of enamel cap morphology in directing deformation behavior; an ability stemming from the stiffness of the enamel cap overlying the more pliable dentin.  相似文献   
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Ernst Heller died 50 years ago in Leipzig. His name is linked to myotomy for the treatment of cardiospasm (achalasia). Many other developments in the field of thoracic surgery and other fields of surgery, such as magnetic removal of projectiles from the brain have been forgotten. The introduction of colors into the operating room (OR) and the construction of modern lighting sources are the most important developments of Heller which can be observed worldwide in all modern ORs. This short review focuses on factors that may have contributed to the delay in recognition of the true value in modern management not only of achalasia but also of many other esophageal motor disorders. Heller first published the use of myotomy in the treatment of achalasia 100 years ago.  相似文献   
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The recurrence of ventral hernias continues to be a problem faced by surgeons, in spite of efforts toward implementing novel repair techniques and utilizing different materials to promote healing. Cadaveric acellular dermal matrices (Alloderm) have shown some promise in numerous surgical subspecialties, but these meshes still suffer from subsequent failure and necessitation of re‐intervention. Here, it is demonstrated that the addition of platelet rich plasma to Alloderm meshes temporally modulates both the innate and cytotoxic inflammatory responses to the implanted material. This results in decreased inflammatory cytokine production at early time points, decreased matrix metalloproteinase expression, and decreased CD8+ T cell infiltration. Collectively, these immune effects result in a healing phenotype that is free from mesh thinning and characterized by increased material stiffness.  相似文献   
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