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41.
BACKGROUND: Screening mammography has led to earlier diagnosis of breast cancer; however, the increased tissue density of young women can complicate mammographic interpretation. We hypothesized that magnetic resonance imaging (MRI) has value in detection of mammographically occult breast cancers, particularly in premenopausal women for whom the sensitivity of mammography is compromised. METHODS: Data were available for 89 women with biopsy-proven breast cancer who had undergone both mammography and breast MRI. Variables evaluated included menopausal status and radiographic findings. Data were analyzed using Fisher's Exact test; P < .05 was considered significant. RESULTS: Of the 89 women in our study, 69 were perimenopausal or postmenopausal and 20 were premenopausal at the time of diagnosis. The malignant lesion was identified on mammography and MRI for a majority of patients. One third of premenopausal women had negative mammography but positive MRI findings. CONCLUSIONS: Our findings support a role for breast MRI in supplementing conventional mammography for early detection of breast cancer in premenopausal women.  相似文献   
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A cohort of 215 sarcoidosis patients from the ACCESS study underwent a clinical evaluation at study enrollment and two years later. Approximately 80% of subjects had an improved or stable FVC, FEV1, chest radiograph determined by Scadding stage, and dyspnea scale. African-Americans had less improvement in FVC than Caucasians (p = 0.04). Patients with erythema nodosum at presentation were more likely to have improvement in the chest radiograph at two-year follow-up (p = 0.007). Patients with a lower annual family income were more likely to worsen with respect to dyspnea (p = 0.01) and more likely to have new organ involvement at two-year follow-up (p = 0.045). The development of new organ involvement over the two year follow-up period was more common in African-Americans compared to Caucasians (p = 0.002) and more likely in those with extrapulmonary involvement at study entry (p = 0.003). There was an excellent concordance between changes in FVC and FEV1 over the two-year period. However, changes in FVC alone were inadequate to describe the change in pulmonary status of the patients, as changes in chest radiographic findings or the level of dyspnea did often but not always move in the same direction as FVC. In conclusion, data from this heterogeneous United States sarcoidosis population indicate that sarcoidosis tends to improve or remain stable over two years in the majority of patients. Several factors associated with improved or worse outcome over two years were identified.  相似文献   
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BACKGROUND: A genetic predisposition to sarcoidosis has long been postulated, although no specific susceptibility genes are known. Candidate genes for the two granulomatous inflammatory disorders with clinical similarities to sarcoidosis, Blau syndrome and Crohn's disease, have been localized to a 40 centimorgan region spanning the chromosome 16 centromere. PATIENTS AND METHODS: Using a sample of 35 African-American sibling pairs, who both had clinically confirmed sarcoidosis, we tested for genetic linkage between the 16p12-q21 interval (the likely location of the Blau syndrome gene) and sarcoidosis. RESULTS: We found no evidence for linkage to any of the eight markers we tested in the 16p12-q21 interval. Ninety percent of the 16p12-q21 region had a LOD score < -2 for a dominant gene conferring a relative risk of 3 or greater for sarcoidosis. One hundred percent of the region had a LOD score < -2 for a dominant gene with a relative risk of 3.5 or greater or recessive gene with relative risk of 2.5 or greater. Based on simulation results we could not exclude a dominant gene with relative risk < 5 at the 0.05 significance level, nor a recessive gene with relative risk < 3, over the entire 16p12-q21 interval. CONCLUSIONS: While the clinical similarities between Blau Syndrome and sarcoidosis suggest genetic homogeneity between the disorders, we found no evidence for linkage of sarcoidosis to the Blau syndrome locus. Our exclusion results suggest that the Blau Syndrome gene does not have a major effect on sarcoidosis susceptibility.  相似文献   
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The myeloid zinc finger gene, MZF-1, regulates the CD34 promoter in vitro   总被引:2,自引:1,他引:2  
Morris  JF; Rauscher  FJ rd; Davis  B; Klemsz  M; Xu  D; Tenen  D; Hromas  R 《Blood》1995,86(10):3640-3647
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The early clinical experience with a 3-Dimensional Fourier Transform Gradient Echo sequence with fat suppression in the evaluation of breast masses is reported. Ten female patients with breast malignancies were pre-operatively evaluated with this sequence and the results compared with the pathological specimens. The scanning protocol included a noncontrast sequence followed by an immediate post-contrast sequence (completed 4.5 min after intravenous contrast injection) and a delayed sequence. Images were assessed for maximum lesion and parenchymal enhancement, lesion size and additional enhancing abnormalities. In six patients, malignant masses enhanced maximally on the immediate post-contrast sequence with parenchyma enhancing maximally on delayed images. In three cases, there was preferential enhancement of malignant lesions over normal parenchyma but to a similar degree on both post-contrast sequences. In one case, both the lesion and parenchyma enhanced maximally on the delayed sequence. Magnetic resonance assessed lesion size accurately and also detected satellite malignancies in one case. However, lesion grade, associated in situ carcinoma and lymphovascular invasion did not impact on lesion enhancement. In this small series, a contrast-enhanced, fat-suppressed 3-D Gradient Echo Sequence detected breast carcinoma with high sensitivity. The technique holds promise but further evaluation is required.  相似文献   
49.
Superficial adenocarcinoma of the esophagus.   总被引:10,自引:0,他引:10  
OBJECTIVE: Experience with treatment and outcome of superficial adenocarcinoma of the esophagus is limited. The purpose of this study was to evaluate the results of surgical management and identify predictors of survival. METHODS: Between September 1985 and December 1999, 122 patients underwent resection. Eighty-nine percent were men (mean age 63 +/- 10 years; range 35-83 years). Sixty (49%) patients were in endoscopic surveillance programs and 48 (39%) had the preoperative diagnosis of high-grade dysplasia. Forced expiratory volume in 1 second was less than 2 L in 12 (12%). Seventy-five (61%) patients underwent transhiatal esophagectomy. Pathologic stage was N1 in 8 (7%). Pulmonary complications necessitating reintubation (respiratory failure) occurred in 10 (8%) patients. Time-related survival models were developed for decision-making (preoperative), prognosis (operative), and hospital care (postoperative). RESULTS: Operative mortality was 2.5%. Survival at 1, 5, and 10 years was 89%, 77%, and 68%. Preoperative decision-making factors associated with ideal outcome were 1-second forced expiratory volume of more than 2 L, surveillance, preoperative diagnosis of high-grade dysplasia, and planned transhiatal esophagectomy. Prognosis was decreased in younger patients and in those with N1 disease. Postoperative respiratory failure increased mortality. CONCLUSIONS: Surgery is the treatment of choice for superficial adenocarcinoma of the esophagus. The ideal patient has a preoperative diagnosis of high-grade dysplasia found at surveillance, good pulmonary function, and undergoes a transhiatal esophagectomy. Discovery of N1 disease or development of postoperative respiratory failure reduces the benefits of surgery.  相似文献   
50.
The prevalence of osteopenia in children with inflammatory bowel disease (IBD) is unknown. The effect of nutritional state, disease activity, and steroid therapy on bone mineral content (BMC) of whole body, lumbar spine, and left femoral neck measured by dual energy x ray absorptiometry in 32 children with IBD was assessed by comparison with 58 healthy local school children. Using the control data, a predicted BMC was calculated taking into account bone area, age, height, weight, and pubertal stage. The measured BMC in children with IBD was expressed as a percentage of this predicted value (% BMC). Mean (SD) % BMC was significantly reduced for the whole body and left femoral neck in the children with IBD (97.0 (4.5)% and 93.1 (12.0)% respectively, p < 0.05). Of the children with IBD, 41% had a % BMC less than 1 SD below the mean for the whole body and 47% at the femoral neck. Reduction in % BMC was associated with steroid usage but not with the magnitude of steroid dose, disease activity, or biochemical markers of bone metabolism. In conclusion, osteopenia is relatively common in childhood IBD and may be partly related to the previous use of steroids.  相似文献   
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