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Background

The purpose of this analysis is to describe the differences in cardiac magnetic resonance characteristics between benign and malignant tumors, which would be helpful for surgical planning.

Methods

This was a prospective cohort study of 130 patients who underwent cardiac magnetic resonance imaging for evaluation of a suspected cardiac mass. After excluding thrombi and tumors without definitive diagnosis, 66 tumors were evaluated for morphologic features and tissue composition.

Results

Of the 66 patients, 39 (59.0%) had malignant tumors and 27 (41.0%) had benign tumors. Patients with malignant tumors were younger when compared with those with benign tumors (age 51 years [42.8-60.0] vs 65 years [60.0-71.0] median). Malignant tumors more often demonstrated tumor invasion (69% vs 0% P < .001) and were more often associated with pericardial effusion (41% vs 7.4% P = .004). Presence of first-pass perfusion (100% vs 33% P < .001) and late gadolinium enhancement (100% vs 59.2%, P < .001) were significantly higher in malignant tumors. In logistic regression modeling, tumor invasion (P < .001) and first-pass perfusion (P < .001) were independently associated with malignancy. Furthermore, using classification and regression tree analysis, we developed a decision tree algorithm to help differentiate benign from malignant tumors (diagnostic accuracy ~90%). The algorithm-weighted cost of misclassifying a malignant tumor as benign was twice that of classifying a benign tumor as malignant.

Conclusions

Our study demonstrates that cardiac magnetic resonance imaging is a useful noninvasive method for differentiating malignant from benign cardiac tumors. Tumor size, invasion, and first-pass perfusion were useful imaging characteristics in differentiating benign from malignant tumors.  相似文献   
3.
The efficacy and safety of a single nocturnal dose of famotidine (40 mg) was evaluated in 30 consecutive patients of duodenal ulcer (DU). Three patients were lost for follow-up and therefore were excluded. The mean age of remaining 27 patients was 34.3 (+/- 9.9) years and male to female ratio was 8:1. The mean size of the DU was 1.21 (+/- 0.79) cm. After a 4-week therapy all patients showed significant improvement and repeat endoscopy in 24 out of 27 patients (89%, 95% confidence interval; 78% to 100%) showed healed ulcer. Clinical assessment of pain relief at 4-week showed significant drop in the mean score of baseline daytime (from 1.85 to 0.13) and baseline nocturnal pain (from 1.70 to 0.10) (p less than 0.0001 and less than 0.0001, respectively). Also shown was the significant decrease in the mean gastrointestinal symptoms score from 5.89 at baseline to only 0.89 at 4-week (p less than 0.0001). Despite that all those who failed to show ulcer healing at 4-week were smokers, logistic regression analysis could not identify smoking or any other risk factors as adverse predictors of ulcer healing. None of the patients experienced significant side effects or adverse reactions. We conclude, that a single nocturnal dose of famotidine is a practical, highly effective and safe approach for the management of DU.  相似文献   
4.
Purification of B16-F1 melanoma autocrine motility factor and its receptor.   总被引:9,自引:0,他引:9  
Tumor autocrine motility factor (AMF) is a cytokine which stimulates both random and directed cell migration by self-producing cells. AMF has been detected in and purified from serum-free conditioned medium of murine B16-F1 melanoma cells. Under nonreducing conditions AMF migrates in sodium dodecyl sulfate-polyacrylamide gel electrophoresis as a single band of Mr 55,000, whereas under reducing conditions it migrates as a single polypeptide of Mr 64,000. Two-dimensional polyacrylamide gel electrophoresis of the purified AMF resolved two polypeptides with isoelectric points of 6.35 (major) and 6.4 (minor). No carbohydrate side chains were detected in the B16-F1 AMF. Purified AMF stimulated B16-F1 cell migration in a dose-dependent fashion and bound directly in a protein-protein-binding assay to the AMF receptor, a cell surface glycoprotein of Mr 78,000 [glycoprotein (gp) 78]. The involvement of gp78 in AMF-stimulated function was demonstrated by motility assays. These results suggest that AMF is the natural ligand for the gp78-AMF receptor.  相似文献   
5.
Over the past two decades, the role of radiolabeled monoclonal antibodies has been steadily growing in clinical practice, particularly for staging and locating a variety of neoplasms. This is due largely to the availability of these products in pharmaceutical quantities as well as the relatively low incidence of adverse reactions following the intravenous administration of antibodies to patients. One particular area of oncology where radiolabeled monoclonal antibodies are most likely to play an extremely important clinical role is in the evaluation of patients with colon and rectal carcinomas. In this report, we review the current utilization of tumor-associated monoclonal antibodies in the preoperative as well as postoperative screening of patients with colorectal carcinoma.  相似文献   
6.
In Karachi, Pakistan, a South Asian megacity with a high prevalence of tuberculosis (TB) and low HIV prevalence, we assessed the effectiveness of fluoroquinolone-based preventive therapy for drug-resistant (DR) TB exposure. During February 2016–March 2017, high-risk household contacts of DR TB patients began a 6-month course of preventive therapy with a fluoroquinolone-based, 2-drug regimen. We assessed effectiveness in this cohort by comparing the rate and risk for TB disease over 2 years to the rates and risks reported in the literature. Of 172 participants, TB occurred in 2 persons over 336 person-years of observation. TB disease incidence rate observed in the cohort was 6.0/1,000 person-years. The incidence rate ratio ranged from 0.29 (95% CI 0.04–1.3) to 0.50 (95% CI 0.06–2.8), with a pooled estimate of 0.35 (95% CI 0.14–0.87). Overall, fluoroquinolone-based preventive therapy for DR TB exposure reduced risk for TB disease by 65%.  相似文献   
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A highly sensitive assay for mammalian lysosomal pepstatin-insensitive proteinase (LPIP) is described using a synthetic peptide substrate coupled to aminotrifluoromethyl coumarin (AFC). LPIP is an endocarboxyl proteinase which has specific sequence requirements of Phe-Phe around the carboxyl terminal. This HPLC based assay can detect patients suffering from late-infantile neuronal ceroid lipofuscinosis (LINCL) and also heterozygote carriers in cultured lymphoid cells and skin fibroblasts. None of the patients analyzed had detectable enzyme activity confirming the defective gene product, while carriers had about 50% activity when compared with the normal controls. Neurological controls comprised of patients with other neurodegenerative disorders have LPIP activities similar to normal controls. LPIP activity is also detectable in amniocytes and chorionic villi. Thus the assay reported can also be used for prenatal diagnosis of LINCL.  相似文献   
9.
We report a case of a 40-year-old man who had presented with a spontaneous suprapubic urinary leak from a well-healed suprapubic cystostomy tract scar, 20 years following a successful scrotal tube substitution urethroplasty done for a post-traumatic urethral stricture. Preoperative contrast studies suggested a recurrent bulbomembranous urethral stricture. Excision biopsy of the suprapubic fistulous tract revealed scar cancer infiltrating the bladder wall. Of 3 similar cases reported in the past, only 1 had bladder involvement. Ours is the second such case with bladder involvement.  相似文献   
10.
Purpose: The frequency of adrenal metastases from non-small cell lung cancer (NSCLC) varies between 4 to 25%. Adrenal metastases are frequently missed (78%) by Computed Tomography (CT) and Magnetic Resonance Imaging (MRI). The purpose of this study was to characterize the patterns of adrenal gland involvement from lung cancer by 18-F-Fluorodeoxyglucose Positron Emission Tomography (18FDG-PET).Methods: Retrospective review of patients evaluated for known or suspected lung carcinoma. Results of 18FDG-PET, CT, MRI, and scans were compared.Results: From February 1996 to May 2000, 91 patients with known (85 patients) or suspected (6 patients) lung cancer were evaluated with 18FDG-PET scan. Twenty-two patients (mean age 63, range 38-88 years) had abnormal adrenal glands by either 18FDG-PET (16 patients), CT (12 patients) or MRI (1 patient). In 13 cases 18FDG-PET scan was ordered to clarify CT or MRI findings. Only 7 patients showed adrenal gland involvement: 5 patients (5.5%) with unilateral disease and 2 patients (2.2%) with bilateral disease. PET depicted unsuspected findings in 9 patients: 8 patients (8.8%) with unilateral disease and 1 patient (1.1%) with bilateral disease.(18)FDG-PET upstaged 9 patients from limited (N1M0) to widespread disease (M1), thus obviating surgical intervention.Conclusion: This study demonstrates the potential of 18FDG-PET scanning in revealing unsuspected adrenal metastases in patients with early stages of NSCLC as well as characterizing CT or MRI equivocal adrenal masses.  相似文献   
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