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Verrucous carcinoma is a variant of squamous cell carcinoma and should be distinguished from benign papilloma and well-differentiated nonverrucous squamous cell carcinoma. It is rare tumor of the sinonasal tract. Occasionally, conventional squamous cell carcinomatous components may be seen in verrucous carcinoma. This entity is called a hybrid verrucous squamous cell carcinoma. We report a case of hybrid verrucous squamous cell carcinoma occurring in the nasal cavity and paranasal sinus of a 67-year-old male. The removed mass shows the typical feature of verrucous carcinoma, but focally conventional squamous cell carcinomatous area is also noted. The treatment of this case follows verrucous carcinoma, but close follow up is mandatory because it may potentially spread to regional lymph nodes in contrast to pure form of verrucous carcinoma.  相似文献   
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DNA-based immunization strategies designed to elicit cellular antitumor immunity offer an attractive alternative to protein- or peptide-based approaches. In the present study we have evaluated the feasibility of DNA vaccination for the induction of CTL reactivity to five different melanoma Ags in vitro. Cultured, monocyte-derived dendritic cells (DC) were transiently transfected with plasmid DNA encoding human MART-1/Melan-A, pMel-17/gp100, tyrosinase, MAGE-1, or MAGE-3 by particle bombardment and used to stimulate autologous PBMC responder T cells. CTL reactivity to these previously identified melanoma Ags was reproducibly generated after two or three stimulations with genetically modified DC. Co-ordinate transfection of two melanoma Ag cDNAs into DC promoted CTL responders capable of recognizing epitopes from both gene products. Coinsertion of genes encoding the Th1-biasing cytokines IL-12 or IFN-alpha consistently enhanced the magnitude of the resulting Ag-specific CTL reactivity. Importantly, DC transfected with a single melanoma Ag cDNA were capable of stimulating Ag-specific CTL reactivity restricted by multiple host MHC alleles, some of which had not been previously identified. These results support the inherent strengths of gene-based vaccine approaches that do not require prior knowledge of responder MHC haplotypes or of relevant MHC-restricted peptide epitopes. Given previous observations of in situ tumor HLA allele-loss variants, DC gene vaccine strategies may elicit a greater diversity of host therapeutic immunity, thereby enhancing the clinical utility and success of such approaches.  相似文献   
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Driven by the need for a readily available, non-immunological tissue that possesses many of the characteristics of normal human skin, tissue-engineered skin has been developed. For over a decade, laboratory grown or processed skin has been under investigation and, in some cases, available as an alternative to autologous grafts. Apligraf, derived from neonatal foreskin and bovine type I collagen, is the first bi-layered living skin equivalent approved in the US and other countries for use in venous ulcers. Apligraf is effective both in the treatment of refractory venous ulcers and for acute wounds such as surgical excision sites and split thickness donor sites. Apligraf is safe and is not clinically rejected. Its ultimate fate is not known, so it may well work to aid healing in a variety of ways including graft 'take' and as a stimulus for healing.  相似文献   
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The molecular mechanisms that link cell-cycle controls to the mitotic apparatus are poorly understood. A component of the Saccharomyces cerevisiae spindle, Ase1, was observed to undergo cell cycle-specific degradation mediated by the cyclosome, or anaphase promoting complex (APC). Ase1 was degraded when cells exited from mitosis and entered G1. Inappropriate expression of stable Ase1 during G1 produced a spindle defect that is sensed by the spindle assembly checkpoint. In addition, loss of ASE1 function destabilized telophase spindles, and expression of a nondegradable Ase1 mutant delayed spindle disassembly. APC-mediated proteolysis therefore appears to regulate both spindle assembly and disassembly.  相似文献   
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PURPOSE: We reviewed our experience with the safety and long-term efficacy of percutaneous endopyelotomy in children with secondary ureteropelvic junction obstruction who previously underwent open pyeloplasty. MATERIALS AND METHODS: Nine patients a median of 7 years old underwent endopyelotomy between June 1985 and July 1995. Anderson-Hynes pyeloplasty had previously been performed in all children. Antegrade endopyelotomy was done with a cold knife in conjunction with balloon dilation in some cases. Postoperative stenting lasted 6 weeks. RESULTS: The median interval between pyeloplasty and endopyelotomy was 7.5 months. Mean operative time was 240 minutes. Percutaneous endopyelotomy was successful in 8 of the 9 patients. One patient who required repeat endopyelotomy after 4 years is presently well at 5 years of followup. Average followup was 5.6 years (range 2 to 10). There was a low morbidity rate, including 1 case of urinary tract infection, 1 of pneumonia and 1 that required blood transfusion. CONCLUSIONS: Percutaneous antegrade endopyelotomy is a safe, effective and durable alternative for children who previously underwent unsuccessful pyeloplasty.  相似文献   
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