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151.
SJ Victor DM Brown EM Horwitz AA Martinez VR Kini JE Pettinga KW Shaheen P Benitez PY Chen FA Vicini 《Canadian Metallurgical Quarterly》1998,82(7):1303-1309
BACKGROUND: Analyses were performed to determine local control and cosmetic outcome of breast carcinoma patients with prosthetically augmented or reconstructed breasts who had received radiation therapy (RT). METHODS: Twenty-one newly diagnosed breast carcinoma patients with prosthetically augmented or reconstructed breasts were treated with external beam RT. All patients received whole breast RT (median dose, 50.4 gray [Gy]) and 19 were boosted to a median dose of 60.4 Gy. A median dose of 50.4 Gy was delivered to the regional lymph nodes in 12 patients. Tissue equivalent bolus material was used in six patients. Seventeen patients received adjuvant systemic therapy. Cosmetic results were evaluated at 3-6-month intervals. RESULTS: With a median follow-up of 32 months, good/excellent cosmetic results were observed in 71% of patients (100% in those with augmented breasts and 54% in those with reconstructed breasts). Four patients (19%) with fair/poor cosmetic outcomes required implant removal and/or revision. Multiple clinical and treatment-related factors were analyzed for their impact on cosmetic outcome. A worsened cosmetic result was observed with increasing stage (P = 0.076), breast reconstruction (vs. augmentation) (P = 0.030), and bolus application (P = 0.016). All patients with fair/poor cosmetic outcomes had time intervals from implant insertion to RT ranging from 53-213 days. Two patients developed an isolated local recurrence within the augmented breast. CONCLUSIONS: Patients with prosthetically augmented breasts can undergo RT and expect good/excellent cosmetic results. Patients with reconstructed breasts are at a significantly greater risk for cosmetic failure. This risk may be related to the higher percentage of patients with advanced disease, those who received bolus application, and those who received earlier delivery of RT (after the cosmetic procedure) in reconstructed breasts. 相似文献
152.
JC van der Voet RB Keus AA Hart FJ Hilgers H Bartelink 《Canadian Metallurgical Quarterly》1998,42(2):247-255
Low frequency impedance measurements of pure egg lecithin (phosphatidylcholine) bilayers have revealed the presence of four layers which can be attributed to the acyl chain, carbonyl, glycerol bridge and phosphatidylcholine regions of the lecithin molecule. Measurements on bilayers formed in the presence of unoxidised-cholesterol revealed that cholesterol molecules were located in the hydrocarbon region of the bilayer with its hydroxyl groups aligned with the carbonyl region of the lecithin molecules. Measurements of oxidised-cholesterol lecithin bilayers revealed that these molecules protruded less into the hydrocarbon region and their polar hydroxyl group aligned with the glycerol bridge region of the lecithin molecule. 相似文献
153.
IuN Lysov AA Cherny? AA Balaev FN Gnuchev KL Beattie AD Mirzabekov 《Canadian Metallurgical Quarterly》1995,29(1):104-113
The opportunity of DNA sequencing by hybridization with oligonucleotide matrix (SHOM) with simultaneously use continuous stacking hybridization and gapped-matrices is considered. The analysis of reconstruction efficiency for various combinations matrices and l-oligonucleotides libraries were made. In most cases combine use of continuous stacking hybridization and gapped matrices permits to decrease the number of additional stacking hybridization twice without lost of efficiency. 相似文献
154.
P Engler-Pinto Júnior J Gama-Rodrigues FP Lopasso AC Cordeiro A Saez-Alquezar AA Laudanna HW Pinotti 《Canadian Metallurgical Quarterly》1996,43(12):1671-1677
BACKGROUND/AIMS: Basal (BAO) and maximum (PAO) hydrochloric acid output after Histalog stimulation, basal pepsinogen (SPL-B), at 60 (SPL-60) and at 90 minutes (SPL-90), and basal gastrin (BG) levels were measured and compared in different gastric (GU) and duodenal (DU) ulcer sites. MATERIAL AND METHODS: Fifty nine patients with peptic ulcer were grouped according to Johnson's classification for gastric ulcers: type I (15), type II (16) type III (12) GU and (16) DU. Fifteen normal subjects were studied as controls. RESULTS: The BAO was greater in the DU than in the control or GU groups. No significant difference was noted in the production of hydrochloric acid after stimulation with Histalog. The SPL-B, at 60 and at 90 minutes was higher in type II GU than in the DU group and controls. The SPL-60 was higher in type II GU patients than in type III GU. Basal gastrin was higher in group DU and types II and III GU compared to the type I GU patients and controls. CONCLUSION: The topographic criteria for differentiating peptic ulcers has low discrimination capacity based on comparison of mean values of HCl acid production, pepsinogen and gastrin serum levels both basal and after stimulation with Histalog due to heterogeneity of these variables in group studies. In these studies, peptic ulcers from different sites should not be grouped as distinct entities except for type II gastric ulcers. 相似文献
155.
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157.
By repeatedly presenting an alien scent to territory-owning beavers, Castor canadensis, we tested two competing hypotheses about the function of scent marking: scent fence and scent matching. The scent-fence hypothesis predicts that territory owners should respond increasingly strongly over time towards a recurrent alien scent because of the ineffectiveness of previous responses. The scent-matching hypothesis predicts that the intensity of response should be the same or decrease because, without the presence of the intruding signaller coupled with the chemical signal, the presence of the scent itself does not advertise the ownership of a territory. The response level of resident beaver families was stable to strangers' anal gland secretions (AGSs) and decreased to strangers' castoreum during a period of 6 days. These results support the scent-matching hypothesis but not the scent-fence hypothesis. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour. 相似文献
158.
AA Sinha BJ Quast MJ Wilson PK Reddy DF Gleason BF Sloane 《Canadian Metallurgical Quarterly》1998,252(2):281-289
Ascorbic acid can recycle alpha-tocopherol from the tocopheroxyl free radical in lipid bilayers and in micelles, but such recycling has not been demonstrated to occur across cell membranes. In this work the ability of intracellular ascorbate to protect and to recycle alpha-tocopherol in intact human erythrocytes and erythrocyte ghosts was investigated. In erythrocytes that were 80% depleted of intracellular ascorbate by treatment with the nitroxide Tempol, both 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) and ferricyanide oxidized alpha-tocopherol to a greater extent than in cells not depleted of ascorbate. In contrast, in erythrocytes in which the intracellular ascorbate concentration had been increased by loading with dehydroascorbate, loss of alpha-tocopherol was less with both oxidants than in control cells. Protection against AAPH-induced oxidation of alpha-tocopherol was not prevented by extracellular ascorbate oxidase, indicating that the protection was due to intracellular and not to extracellular ascorbate. Incubation of erythrocytes with lecithin liposomes also generated an oxidant stress, which caused lipid peroxidation in the liposomes and depleted erythrocyte alpha-tocopherol, leading to hemolysis. Ascorbate loading of the erythrocytes delayed liposome oxidation and decreased loss of alpha-tocopherol from both cells and from alpha-tocopherol-loaded liposomes. When erythrocyte ghosts were resealed to contain ascorbate and challenged with free radicals generated by AAPH outside the ghosts, intravesicular ascorbate was totally depleted over 1 h of incubation, whereas alpha-tocopherol decreased only after ascorbate was substantially oxidized. These results suggest that ascorbate within the erythrocyte protects alpha-tocopherol in the cell membrane by a direct recycling mechanism. 相似文献
159.
OBJECTIVE: To assess the potential actions of medical school deans, graduate medical education (GME) committee chairs, and hospital chief executive officers (CEOs) regarding future funding reductions for residency training. Specifically, institutions with emergency medicine (EM) residencies were surveyed to see whether EM training was disproportionally at risk for reductions. METHODS: An anonymous 2-page survey was used. Ninety-eight EM residency programs were identified using the American Medical Association Graduate Medical Education Directory 1994-95. Seventy deans, 102 GME chairs, and 97 hospital CEOs were identified. The survey posed a hypothetical 25% forced reduction in residency positions and asked the decision makers for their responses. Options included: 1) proportional reductions of training positions from all residencies, 2) proportional reductions in either primary care or specialty residency positions, or 3) reduction or elimination of specific training programs. The survey asked for a first and second choice of residencies to be reduced or eliminated from an alphabetical list of 17. The survey elicited explanations for each program reduction. RESULTS: 200 (74%) of 269 surveys were returned. Eighty-four responders selected specific residencies to be reduced or eliminated. EM was selected 8 times, making EM the seventh most vulnerable residency to be targeted for reductions. The decision makers who selected proportional reductions chose to reduce across all residencies 32 times, among only the specialty residencies 129 times, and among only the primary care residencies 3 times. CONCLUSIONS: In the setting of anticipated residency cuts, favored proportional reductions in specialty residencies would likely affect EM training. However, most GME decision makers with an existing EM residency program do not consider the EM residency a top choice to be reduced or eliminated. 相似文献
160.