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101.
Jonathan Cook Neil Prose Mitchell Heflin 《Dermatologic surgery》2003,29(9):1994; author reply 1994-1994; author reply 1995
102.
Jonathan A. Haas M.D. Deborah Markiewicz M.D. Robbie Medbery M.D. Lawrence J. Solin M.D. 《The breast journal》1997,3(4):191-195
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
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
103.
Jonathan E. Bishop Giles E. Santyr Frederick Kelcz Donald B. Plewes 《Journal of magnetic resonance imaging : JMRI》1997,7(4):716-723
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
104.
105.
Van Blerkom J 《Reproductive biomedicine online》2007,14(2):191-200
The subplasmalemmal cytoplasm of the mouse and human oocyte contains proteins, high-polarized mitochondria and for the mouse, mRNA that appears to have regulatory roles in early development. For the human, the irreversible loss of certain proteins and high-polarized mitochondria into small fragments that arise spontaneously and incorporate the subplasmalemmal cytoplasm has been suggested to have developmental consequences for the affected cell(s). Time-lapse studies have shown that fragments of this type can be resorbed during cleavage and in certain instances, their disappearance largely restores phenotypic normality to the human embryo. Time-lapse microscopy was used to examine this type of fragmentation and describe behaviours associated with their fusion or resorption, or both, in early human embryos. The transfer of fragments containing high-polarized mitochondria (delta psi m(HIGH)) labelled with a potentiometric fluorescent stain between embryos, and to oocytes and parthenogenetically activated eggs, demonstrates fragment resorption by incorporation of high-polarized mitochondria in the subplasmalemmal cytoplasm. The results indicate the potential for spontaneous transposition of subplasmalemmal regulatory elements within and between cells exists in early human embryos and that loss or gain of function may have different developmental impacts on affected cells. The location of incorporated mitochondria confirms their stability in subplasmalemmal domains, and suggests the possibility that a high polarity may be a factor in spatial specification. 相似文献
106.
107.
Jonathan M Hodgson Kevin D Croft Trevor A Mori Valerie Burke Lawrence J Beilin Ian B Puddey 《The Journal of nutrition》2002,132(1):55-58
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
108.
Jonathan S. Jahr Fedor Lurie Bernd Driessen Jessica A. Davis Robert Gosselin Robert A. Gunther 《Journal canadien d'anesthésie》2002,49(3):243-248
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
109.
Luiz C M Pereira Vanessa N Palter Anthony E Lang William D Hutchison Andres M Lozano Jonathan O Dostrovsky 《Movement disorders》2004,19(12):1485-1492
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
110.
Jonathan P Arm 《Allergy and asthma proceedings》2004,25(1):37-42
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