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101.
Halpern EJ  Frauscher F 《Radiology》2002,224(1):293; author reply 293-293; author reply 294
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The authors describe a 42-year-old man with parathyroid hyperplasia secondary to chronic renal failure. Parathyroidectomy was indicated because of persistent hypercalcemia and an increasing parathyroid hormone level despite medical management. A parathyroid sestamibi scan was performed immediately before operation and a gamma-detecting probe was used during operation. Six parathyroid glands weighing nearly 21 g were present. Without the use of the gamma-detecting probe during operation, one of the glands would have been missed. The efficacy of sestamibi scanning with parathyroid hyperplasia is discussed.  相似文献   
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BACKGROUND AND OBJECTIVE: To report the outcome of combined verteporfin photodynamic therapy (PDT) and intravitreal triamcinolone acetonide (IVTA) for the treatment of choroidal neovascularization (CNV) with serous pigment epithelium detachment (PED) due to age-related macular degeneration (AMD). PATIENTS AND METHODS: The files of all consecutive patients with CNV and serous PED who received PDT and IVTA either primarily (primary treatment group) or following previous unsuccessful PDT (secondary treatment group) were reviewed for visual and angiographic results. RESULTS: Ten patients (11 eyes) were included. Mean number of PDT sessions was 3.18; 8 eyes received one IVTA injection and 3 eyes received two IVTA injections. Thirty-six percent of patients retained their initial visual acuity after a mean follow-up of 15.3 months. Loss of 3 or more Snellen lines was noted in 2 of 3 eyes in the primary treatment group and 5 of 8 eyes in the secondary treatment group. Increased intraocular pressure developed in 3 patients and was controlled by topical medications. CONCLUSIONS: Although combined PDT and IVTA may be considered for CNV with serous PED in patients with poor prognosis with PDT alone, the regimen as administered in this small series was not beneficial. Further studies are required to determine whether alternate sequences, timing, or doses would yield a better outcome.  相似文献   
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PURPOSE: There is a need to identify lung cancer prevention mechanisms. All-trans-retinoic acid (RA) was reported previously to inhibit N-nitrosamine-4-(methylnitrosamino)-1-(3 pyridyl)-1-butanone (NNK) carcinogenic transformation of BEAS-2B human bronchial epithelial cells (J. Langenfeld et al., Oncogene, 13: 1983-1990, 1996). This study was undertaken to identify pathways targeted during this chemoprevention. Experimental Design: Because epidermal growth factor receptor (EGFR) overexpression is frequent in non-small cell lung cancers (NSCLC) and bronchial preneoplasia, BEAS-2B cells, carcinogen-transformed BEAS-2B(NNK) cells, and retinoid chemoprevented BEAS-2B(NNK RA) cells were each examined for EGFR expression. Whether RA treatment regulated directly EGFR expression or reporter plasmid activity was studied. RA effects on epidermal growth factor (EGF) induction of EGFR-phosphotyrosine levels, cyclin D1 expression and mitogenesis were examined in BEAS-2B cells. RESULTS: Findings reveal that NNK-mediated transformation of BEAS-2B cells increased EGFR expression. RA treatment repressed EGFR expression and reporter plasmid activity in these cells. This treatment reduced EGF-dependent mitogenesis as well as EGFR-associated phosphotyrosine levels and cyclin D1 expression. These findings extend prior work by highlighting EGFR as a chemoprevention target in the lung. Notably, RA treatment prevented transformation as well as outgrowth of EGFR overexpressing bronchial epithelial cells, despite NNK exposure. After acute NNK exposure, p53-induced species that appear after DNA damage or oxidative stress were evident before an observed increase in EGFR expression. CONCLUSIONS: These findings indicate how effective chemoprevention prevents carcinogenic transformation of bronchial epithelial cells when repair of genomic damage does not select against EGFR overexpressing cells. This implicates EGFR as a chemoprevention target in the carcinogen-exposed bronchial epithelium.  相似文献   
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Ethnic disparities in the treatment of stage I non-small cell lung cancer   总被引:3,自引:0,他引:3  
RATIONALE: Important variations exist in the treatment of non-small cell lung cancer. Because resection is the most effective treatment for patients with early disease, disparities in surgical rates can generate considerable differences in outcomes. OBJECTIVE: We analyzed data from a national population-based registry to evaluate disparities in the treatment of Hispanic and white patients with stage I lung cancer and to assess the extent to which these inequalities explain survival differences. METHODS: This study included 16,036 Hispanic and white patients with stage I lung cancer diagnosed between 1991 and 2000. Cases were identified from the Surveillance, Epidemiology, and End Results registry. Survival was compared among white and Hispanics using Kaplan-Meier curves. Stratified survival curves and Cox regression were used to evaluate whether inequalities in stage (IA vs. IB) and resection could explain survival differences. RESULTS: Hispanics had worse overall and lung cancer-specific survival compared with whites (p = 0.04 and 0.008, respectively). Five-year lung cancer survival was 54% for Hispanics versus 62% for whites. Hispanics were more frequently diagnosed with stage IB disease (p = 0.0002) and less likely to undergo resection (p = 0.03). Among resected patients, survival was similar for the two groups, as it was among those who did not undergo unresection. After adjusting for surgery and stage, there was no difference in survival between groups. CONCLUSIONS: Hispanics with stage I lung cancer had worse survival as compared with whites. These disparities are largely explained by lower rates of resection and higher probability of diagnosis at stage IB. Future work must delineate why Hispanics are receiving less surgery.  相似文献   
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