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321.
G Medeiros-Neto MJ Gil-Da-Costa CL Santos AM Medina JC Silva RM Tsou M Sobrinho-Sim?es 《Canadian Metallurgical Quarterly》1998,83(11):4162-4166
A very large cervical tumor that extended to the upper mediastinum was seen in a newborn after an uneventful pregnancy. The computed axial tomography scan confirmed the presence of a solid mass with precise limits and scattered foci of calcifications situated in the anterolateral region of the neck. The infant underwent thyroidectomy on the seventh day after birth. Pathological examination revealed a follicular carcinoma of the thyroid and probable dyshormonogenetic hyperplastic goiter. At 5 months of age, whole body scans indicated the presence of lung and bone metastases, which were treated with therapeutic doses of radioiodine. Genomic DNA was obtained from the newborn, her parents, her paternal aunt, and her paternal grandparents. Denaturing gradient gel electrophoresis analysis of PCR fragments corresponding to exon 14 of the thyroid peroxidase (TPO) gene indicated the presence of a mutant TPO allele present in the propositus, her father, and her paternal grandmother. Sequencing of the TPO gene demonstrated a mutation resulting from an insertion of a single extra cytosine in a stretch of seven cytosines at positions 2505-2511. The insertion caused a frame shift and a stop signal in exon 16. This sequence would translate into a structurally modified and probably inactive TPO protein. We conclude that the aggressive thyroid metastatic carcinoma arose from a dyshormonogenetic goiter caused by a defective TPO protein. 相似文献
322.
323.
C Garcia Montes NA Brandalise R Deliza MF Servidoni JG Ferraz AF Magalh?es 《Canadian Metallurgical Quarterly》1998,33(5):747-749
The authors report a case of a 13-year-old girl with Barrett's esophagus who underwent antireflux surgery and was subsequently treated with endoscopic thermal coagulation using bipolar electrocoagulation. Follow-up endoscopy 15 months after completion of the endoscopic therapy showed normal esophageal mucosa without intestinal metaplasia. Longer follow-up is needed to assess the long-term effects of endoscopic treatment of the Barrett's mucosa with thermal coagulation, and this procedure should still be considered under investigation. 相似文献
324.
This paper presents a procedure for finding the reliability-based optimum design of cable-stayed bridges. The minimisation problem is stated as the minimisation of stresses, displacements, reliability and bridge cost. A finite-element approach is used for structural analysis. It includes a direct analytic sensitivity analysis module, which provides the structural behaviour responses to changes in the design variables. An equivalent multicriteria approach is used to solve the non-differentiable, non-linear optimisation problem, turning the original problem into the sequential minimisation of unconstrained convex scalar functions, from which a Pareto optimum is obtained. Examples are given illustrating the procedure. 相似文献
325.
This paper investigates the work function adjustment on fully silicided (FUSI) NiSi metal gates for dual-gate CMOS, and how it is effected by the poly-Si dopants. By comparing FUSI on As-, B-, and undoped poly-Si using the same p-Si substrates, it is shown that both As and B influence the work function of NiSi FUSI gate significantly, with As showing more effects than B possibly due to more As pile-up at the NiSi-SiO/sub 2/ interface. No degradations on the underlying gate dielectrics are observed in terms of interface state density (D/sub it/), fixed oxide charges, leakage current, and breakdown voltage, suggesting that NiSi FUSI is compatible with dual-gate CMOS processing. 相似文献
326.
Jong‐Hoi Kim Hyun‐Soo Kim Eun‐Deok Sim Kang‐Ho Kim Oh‐Kee Kwon Kwang‐Ryong Oh 《ETRI Journal》2004,26(4):344-350
We propose a filter‐free wavelength conversion using a Mach‐Zehnder interferometer with monolithically integrated 2×2 multimode interference semiconductor optical amplifiers (MMI‐SOAs). The device has been optimized by considering a non‐homogeneous carrier distribution due to the self‐imaging properties of the MMI‐SOA. Static measurements show an extinction ratio of up to 18 dB and an input signal rejection ratio of up to 20 dB. 相似文献
327.
PURPOSE: During the last few years there has been an increasing interest in evaluating quality of life (QOL) data regarding surgical treatment. METHODS: The present study comments the efficacy of laparoscopic antireflux surgery after required Nissen fundoplication of 70 patients. Therefore, the German Gastrointestinal Quality of Life Index (GIQLI) was used to query the patients preoperatively and three times after surgery up to 1 year. RESULTS: Preoperatively, we found a low general GIQLI score (mean 92.7 points), which increased 6 weeks postoperatively (116.8 points), 3 months (124.8) and 1 year (mean 123.9 points) significantly and is now comparable to the healthy population (122.6 points). CONCLUSION: It is our opinion that the efficacy of the treatment of gastroesophageal reflux disease with required Nissen fundoplication can also be documented and discussed by using QOL. 相似文献
328.
329.
László Mérõ 《Artificial Intelligence》1984,23(1):13-27
This paper describes an improved version of two previously published algorithms in the area: and B. The new approach is based on considering the estimate ?(n) on node n as a variable rather than as a constant. The new algorithm thus improves the estimate as it goes on, avoiding some useless node expansions. It is proved to never expand more nodes than B or and to expand a much smaller number of them in some cases.Another result of the paper is a proof that no overall optimal algorithm exists if the cost of an algorithm is measured by the total number of node expansions. 相似文献
330.
A linear programming (LP) model has been developed to optimize the amount of power system peak load reduction through scheduling of control periods in commercial/industrial and residential load control programs at Florida Power and Light Company, USA. The LP model can be used to determine both long and short term control scheduling strategies and for planning the number of customers which should be enrolled in each program. Results of applying the model to a forecasted late 1990s summer peak day load shape are presented. It is concluded that LP solutions provide a relatively inexpensive and powerful approach to planning and scheduling load control. Also, it is not necessary to model completely general scheduling of control periods in order to obtain near best solutions to peak load reduction 相似文献