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51.
Abstract: For the women with early-stage breast cancer who are candidates for breast conservation therapy, re-excision of the primary tumor bed has commonly been used in patients for several indications. These indications include positive margin or uncertain margin status of the primary excision or residual microcalcifications on postbiopsy mammogram. If the pathology from the re-excision does not confirm negative margin status, mastectomy is generally recommended. This article examines patients who have undergone a second re-excision (i.e., a lumpectomy followed by two re-excisions) who have been treated with breast conservation therapy rather than a mastectomy.
From September 1977 to November 1995, 1,562 patients underwent breast conserving therapy at this institution. Seven hundred forty of these patients underwent a re-excisional biopsy because of positive or uncertain margin status or residual microcalcifications after the first excision. Four patients (0.5%) underwent a second re-excision because of positive or uncertain margin status or residual microcalcifications on mammogram after the first re-excision. The final margin status after the second re-excision of all four patients was negative. The radiation dose was 4,600–5,000 cGy to the whole breast followed by a conedown to bring the total dose to 6,400–6,800 cGy to the primary tumor bed.
Follow-up in the four patients was 13 years, 4 years, 14 months, and 8 months respectively. All four patients are clinically without disease and have not had a locoregional recurrence. Cosmesis was excellent in all four patients. One patient had an adriamycin-induced recall reaction causing a cellulitis, which resolved with antibiotics. There were no other complications.
Highly selected patients may undergo breast-conserving therapy after a second re-excision. Good outcome and cosmesis can be achieved for this small subset of patients with avoidance of a mastectomy.  相似文献   
52.
The effect of keyhole data acquisition on quantitative analysis of dynamic MRI was examined. Experiments were performed retrospectively on raw data obtained from clinical dynamic contrast-enhanced breast imaging procedures. The effects of keyhole phase-encoding acquisition and type of reconstruction algorithm on the accuracy of derived quantitative parameters was assessed. Results indicate that the minimum keyhole size used should be restricted by the approximate minimum size of the expected lesions. Furthermore, reconstruction algorithms that offer improved image resolution do not circumvent this restriction.  相似文献   
53.
54.
Prospective studies suggest that tea may protect against cardiovascular disease. A potential mechanism for such an effect involves inhibition of lipid peroxidation by polyphenolic antioxidants derived from tea. Our objective was to determine whether regular ingestion of tea could inhibit in vivo lipid peroxidation. Two controlled intervention studies assessed the effects of regular ingestion of tea on lipid peroxidation determined by measurement of urinary F(2)-isoprostane excretion. Study 1: The effects of 1000 mL/d of green tea and black tea were compared with hot water containing caffeine in 13 subjects with elevated blood pressure using a randomized 3-period (7 d each) crossover design. Study 2: The effects of 1250 mL/d of black tea were compared with hot water in 22 subjects with mildly raised serum total cholesterol concentrations using a randomized 2-period (4 wk each) crossover design. F(2)-isoprostane excretion was not altered after regular ingestion of green tea (273 +/- 48 pmol/mmol creatinine) or black tea (274 +/- 39 pmol/mmol creatinine) in comparison with hot water (263 +/- 47 pmol/mmol creatinine; Study 1), or by regular ingestion of black tea (334 +/- 71 pmol/mmol creatinine) in comparison with hot water (355 +/- 75 pmol/mmol creatinine; Study 2). These results do not support the suggestion that polyphenolic antioxidants derived from tea inhibit in vivo lipid peroxidation.  相似文献   
55.
PURPOSE: Accuracy of measurement of low hemoglobin concentrations using the HemoCue, a B-hemoglobin photometer (HemoCue AB, Angelholm, Sweden) may exhibit significant variability. Infusion of hemoglobin-based oxygen carriers (HBOC) results in low concentrations of plasma hemoglobin. Our study assessed B-hemoglobin photometer measurement accuracy of three HBOC: (hemoglobin glutamer-200 (bovine; Oxyglobin, Biopure Corp., Cambridge, MA, USA); hemoglobin glutamer-250 (bovine; Hemopure, Biopure Corp, Cambridge, MA, USA), and hemoglobin-raffimer, (human; Hemolink, Hemosol, Inc., Toronto, Ontario, Canada). METHODS: In the laboratory, 45 split canine plasma samples were mixed with hemoglobin glutamer-200 (8.13, 16.25, 32.5 g x L(-1) concentrations), 45 samples were mixed with hemoglobin glutamer-250 (8.13, 16.25, 32.5 g x L(-1) concentrations), 45 with hemoglobin-raffimer (12.5, 25.0, 50.0 g x L(-1) concentrations), and measured. Plasma samples without HBOC served as control. Hemoglobin concentration was determined by a laboratory analyzer (Coulter Corporation, Hiafeah, FL, USA) and B-hemoglobin photometer (HemoCue, Angelholm, Sweden). Two independent technicians performed blinded sample measurements and randomly tested each sample five times. Results were analyzed according to Bland and Altman analysis. RESULTS: B-hemoglobin photometer demonstrated high repeatability for all three HBOCs. Repeatability coefficients were 0.37 g x L(-1) and 0.48 g x L(-1) for hemoglobin glutamer-200, 0.39 g x L(-1) and 0.4 g x L(-1) for hemoglobin glutamer-250 and 1.07 g x L(-1) and 0.85 g x L(-1) for hemoglobin-raffimer. An acceptable agreement was found between the B-hemoglobin photometer and the laboratory analyzer for all three HBOCs tested. CONCLUSION: The B-hemoglobin photometer accurately determined the concentration of three HBOC solutions dissolved in canine plasma.  相似文献   
56.
The pathophysiological changes in neural activity that characterize multiple system atrophy (MSA) are largely unknown. We recorded the activity of pallidal neurons in 3 patients with clinical and radiological features of MSA who underwent unilateral microelectrode-guided pallidotomy for disabling parkinsonism. Findings in these patients were compared with 4 control patients with a clinical diagnosis of Parkinson's disease (PD). The position, firing rates, and firing patterns of single neurons in the pallidal complex were analyzed in both MSA and PD patients. The mean spontaneous firing rate of neurons in the internal segment of the globus pallidus internus (GPii) was significantly lower in MSA than in PD patients. There were no significant differences between MSA and PD patients, however, in firing rates of neurons in the external globus pallidus (GPe) or in the external segment of GPi (GPie). In addition, no significant differences in firing pattern were found between MSA and PD patients. In conclusion, this study has shown that firing rates of neurons in GPii but not in GPie and GPe are different in MSA patients compared with that in PD patients, a finding that may reflect the poor clinical results of pallidotomy reported in patients with MSA.  相似文献   
57.
Since the elucidation of the structure of the cysteinyl leukotrienes (LTs) > 20 years ago, considerable progress has been made in our understanding of the role of these molecules in health and disease, particularly regarding bronchial asthma. This study will review the biochemistry of the 5-lipoxygenase pathway for LT generation. It will discuss the early evidence that LTs, the cysteinyl LTs in particular, have the biological properties expected for molecules that participate in the pathogenesis of bronchial asthma and the evidence for their formation in the airways of asthmatic individuals. It will briefly review tile evidence that LT-modifying drugs are effective in the management of bronchial asthma and will discuss novel developments in our understanding of the proinflammatory properties of the LTs including their role as autocrine mediators of leukocyte responses. The pharmacogenomics of 5-lipoxgenase and LTC4 synthase in bronchial asthma will be discussed.  相似文献   
58.
This double blind, randomized, parallel, placebo-controlled study investigates whether clonazepam accelerates and/ or increases the overall response in patients with obsessive compulsive disorder (OCD) who are treated with sertraline. Thirty-seven patients were randomized with 20 in the sertraline and clonazepam group and 17 in the sertraline and placebo groups. Male and female outpatients, age 18-65 years, met criteria for a primary diagnosis of obsessive compulsive disorder according to DSM-IV, as determined by the structured clinical MINI interview. Appropriate safety and efficacy parameters were measured throughout the study. The determination of efficacy was based primarily on changes from baseline to the last observation taken through week 12. Analysis revealed no significant difference between groups at endpoint on the main scale.  相似文献   
59.
The purposes of this investigation were to standardize and validate a simple quantitative method for performing radionuclide solid gastric emptying that can be used for any dual-head gamma-camera and to establish reference values. METHODS: After eating a solid meal (egg sandwich) labeled with a radionuclide, 20 healthy volunteers (9 male, 11 female) underwent a 90-min gastric-emptying study performed with a triple-head gamma-camera. Two sets of 3 simultaneous projections were acquired sequentially for 30 s each: anterior, right posterior oblique (RPO), left posterior oblique (LPO), posterior, left anterior oblique (LAO), and right anterior oblique (RAO), and this sequence was repeated continuously for 90 min. Time-activity curves were generated using a gastric region of interest for each of the views as well as the conjugate-view geometric mean (GM) data for the anterior/posterior, LAO/RPO, and RAO/LPO combinations. Quantitative parameters were determined: percentage gastric emptying (%GE) at 90 min, half-time (min) based on an exponential fit, and clearance rate (%/min) based on a linear fit. Reference values were determined on the basis of a 95% confidence interval of the t distribution. The results were statistically analyzed and compared. RESULTS: The %GE reference values were greater for the anterior/posterior GM (>or=33%) than for the LAO (>or=31%) and anterior (>or=30%) GMs. The 3 %GE GM methods, the 3 exponential-fit GM methods, and the 3 linear-fit GM methods had high correlation coefficients (r >or= 0.874), and with only a single exception, there was no statistical difference among them. The LAO method and LAO/RPO GM mean method correlated strongly (r = 0.900) and had similar mean values (52% vs. 51%) and reference values (29% vs. 30%). All 3 methods of GM quantification also correlated strongly, and there was no significant difference among them. CONCLUSION: We have described and validated a simple method for radionuclide solid gastric emptying that can be used with a dual-head gamma-camera. We recommend the anterior/posterior GM method and have established reference values (>or=33%).  相似文献   
60.
An unusual association with Raynaud's phenomenon   总被引:1,自引:1,他引:0  
A 36-yr-old lady with a year of typical Raynaud's and polyarthralgiahad a normal examination other than cold peripheries and bloodpressure of  相似文献   
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