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Objective: The options available for the treatment of a nonsecreting pituitary macroadenoma that has been incompletely resected include reoperation, fractionated radiation therapy, and radiosurgery. Reoperation in this setting may be hindered by the same obstacles that prevented a complete resection during the initial surgical procedure, and should prompt consideration of an alternate approach or exposure. Methods: Between January 1998 and December 2003, 10 consecutive patients were referred to the Department of Neurosurgery at the University of Texas Southwestern Medical Center for the evaluation of a nonsecreting pituitary macroadenoma that measured 3 cm or greater in diameter despite having undergone an attempt at a complete resection elsewhere. Each of these patients was reoperated using a Le Fort I maxillotomy to enhance the exposure provided by a traditional transsphenoidal approach. Results: A total or near total (> 95%) resection was achieved in each case. One patient required reoperation for the repositioning of a fat graft to treat a cerebrospinal fluid fistula and one patient experienced a worsening of anterior pituitary function postoperatively. Five patients noted improved vision and no patient experienced further visual loss. Three patients have required subsequent treatment of small foci of recurrent or progressing tumor with stereotactic radiation therapy. No patient has received fractionated radiation therapy. Conclusion: The added exposure provided by a Le Fort I maxillotomy facilitates the resection of pituitary macroadenomas that have been incompletely resected by a traditional transnasal, trans-sphenoidal approach.  相似文献   
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Experimental studies have shown that positron emission tomography (PET) with 13N-labeled ammonia provides accurate quantification of regional myocardial blood flow (MBF) under rest and stress conditions. To establish the clinical utility of this method, the interobserver variability and the temporal variability of serial measurements of blood flow and coronary flow reserve (CFR) must be known. This study investigated the interobserver and temporal reproducibility of 13N-labeled PET for measurement of MBF and CFR.  相似文献   
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Standard treatment for advanced rectal carcinoma currently includes surgery, radiotherapy, and chemotherapy. Although there are theoretic advantages to preoperative irradiation, it is often not performed because of the prolonged delay of surgery and the purported increase in perioperative complications. A pilot study was undertaken at our institution to evaluate a treatment protocol advocated by Dr. Papillon that offers a shorter treatment time and less patient morbidity than conventional preoperative therapy for rectal carcinoma. Twenty patients with rectal cancer underwent the preoperative regimen that consisted of 3,000 cGy delivered in 10 fractions over 12 days with concomitant 5-fluorouracil and mitomycin-C. Complications were acceptable. Local recurrence was lower than in most reported trials, and survival rates were comparable. Additional benefits of the protocol include lower radiation morbidity to the patient and a decreased delay between diagnosis and surgery.  相似文献   
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The role of growth factors and cytokines in the impaired healing of chronic leg ulcers remains uncertain. The aim of this study was to determine whether changes in the amount and location of cytokines and growth factors may be associated with impaired healing in chronic leg ulcers. Biopsies from leg ulcers of 21 patients and from normal skin of nine healthy volunteers were examined immunohistochemically for selected growth factors and cytokines. Greater staining intensity was found in keratinocytes at the edges of ulcers compared to normal skin, or skin adjacent to the ulcers. Staining at the ulcer edge was more intense in nonhealing ulcers for only vascular endothelial growth factor and platelet-derived growth factor, whereas staining in the adjacent skin was more intense for all factors in the nonhealing phase. For all factors staining was cytoplasmic, suggesting production in these areas. This study shows up-regulation of the production of cytokines and growth factors in keratinocytes of chronic leg ulcers that is greater when the ulcers are nonhealing.  相似文献   
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BACKGROUND: Inflammatory bowel disease is associated with increased mucosal release of eicosanoids. Among these, thromboxane A2 has been proposed as a possible inflammatory mediator; its suppression may be a useful therapeutic option. METHODS: Using a tissue incubation technique, we compared release of immunoreactive thromboxane B2 by colonic biopsies from patients with ulcerative colitis, Crohn's disease and controls, and assessed the inhibitory effect of picotamide, a thromboxane synthesis inhibitor-receptor antagonist, which has been widely used in Italy for management of ischaemic heart and cerebrovascular disease. RESULTS: Increased amounts of thromboxane B2 were released from biopsies from patients with active ulcerative colitis (median 238 pg/20 min/mg wet weight (interquartile range 147- 325), n = 12) and active Crohn's disease (252 (174-450), 6) compared with those from patients with quiescent ulcerative colitis (95 (61- 140), 12) or Crohn's disease (105 (57-201), 13), or controls (136 (64- 206), 8). Incubation with picotamide at concentrations between 100 microM and 1 mM reduced thromboxane B2 release (IC50 890 microM). CONCLUSION: Since increased thromboxane A2 production may have pathogenetic importance, thromboxane synthesis inhibitor-receptor antagonists such as picotamide merit therapeutic trial in the management of inflammatory bowel disease.  相似文献   
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