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21.
E Campagnutta R Cannizzaro M De Cicco G De Piero G Giorda F Sopracordevole A Parin C Scarabelli 《Canadian Metallurgical Quarterly》1998,50(7-8):305-311
BACKGROUND AND AIMS: Intestinal obstruction is a frequent cause of death in patients suffering from gynecological cancer, who have undergone multiple treatment in the form of surgery and/or chemotherapy and/or radiotherapy. The usual form of rescue treatment consists in the use of a nasogastric tube to administer support and analgesic treatment. Surgical gastrostomy is not a viable proposition in these extremely weak patients with large masses compressing and displacing the stomach. Percutaneous endoscopic gastrostomy (PEG), a technique first introduced for nutritional purposes, can be beneficially used to achieve decompression in these patients. METHODS: PEG was performed in a total of 67 patients who had already undergone multiple treatment for abdominal-pelvic neoplasia with upper gastrointestinal obstruction, who could no longer be operated and who had a life expectancy of less than sixty days. In three cases positioning was not possible owing to the lack of transillumination of the gastric and abdominal wall. 54/64 patients had previously undergone at least two operations. RESULTS: Esophagogastric lesions were found in 29% of patients, some of which were attributed to the nasogastric tube. Symptomatic wellbeing was obtained in 76.5% a few days after PEG. PEG remained in situ from 4 to 472 days. Slight peristomal infection was observed in 9% of cases. In seven cases it was necessary to add octreotide owing to the reappearance of symptoms. CONCLUSIONS: PEG is relatively easy to use and allows obstructive symptoms to be resolved in the majority of patients. Special medical skills are not required and the patient may be easily managed at home together with support therapy and pain management. Once PEG has been performed, it is possible to take fluids and semi-liquid foods, offering the patient a chance to taste flavours which have often been forgotten. PEG enables neoadjuvant chemotherapy to be performed in patients with previously untreated intestinal obstruction. 相似文献
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G Chessa Ricotti R Cutrì A De Bernardi M Funis S Frediani 《Canadian Metallurgical Quarterly》1995,17(3):271-273
The authors describe 5 cases, 3 boys and 2 girls, with idiopathic growth hormone deficiency in prepubertal age, treated with human growth hormone. In four of five cases the response to treatment with GH was relevant. Only in one case (F1) the response was negative. The results of this study confirm that rhGH is a safe and effective therapy in children with GHD. 相似文献
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26.
Nicholas Biery Marc De Graef Jack Beuth Rafel Raban Andrew Elliott Tresa M. Pollock Curt Austin 《Metallurgical and Materials Transactions A》2002,33(10):3127-3136
Tensile experiments have been performed on specimens of four different investment-cast TiAl-based alloys with variations in
casting conditions. The average ductilities obtained in these experiments vary between approximately 0.8 to 2.0 pct plastic
strain to failure in tension. By using the three-parameter form of the Weibull relation, with the 0.2 pct offset yield strength
as the minimum failure strength, the resulting variability in the data can be quantified and is found to be similar for those
alloys with similar microstructural scale (grain size). Large variations in lamellar volume fraction, segregation, and phase
distribution have a minor influence on property variability, compared to changes in the scale of the grain structure caused
by either variations in cooling rate during casting or the addition of grain refiners. 相似文献
27.
Oliveira M. Dart-Mao Cheung C. Al-Zayed A. Chio I.-F.F. Swisher R.R. Lecuyer F. DeLisio M.P. 《Antennas and Propagation, IEEE Transactions on》2002,50(5):698-702
Grid-mixer arrays can achieve high linearity and dynamic range through quasi-optical power combining. We present a 100-element single-ended diode grid mixer operating at 2.45 GHz. Each element incorporates two diodes in series. We measure an input third-order intercept of 11 W (40.5 dBm), and output third-order intercept of 3.4 W (35.4 dBm), and an associated conversion loss of 5.1 dB. The power-handling capability of the array is 100 times larger than that of a microstrip mixer using a single element. The local oscillator (LO) drive requirement for the entire array is 1.4 W (31.6 dBm). The angular dependence of the array's IF power is also presented and is in agreement with theory 相似文献
28.
用迭代法消除数字图像放大后的模糊 总被引:7,自引:3,他引:4
用迭代法对数字图像经过插值放大后产生的模糊问题进行了研究,把数字图像插值放大造成的模糊看成是点扩散函数与清晰图像卷积的结果,根据插值算法可以得到点扩散函数,由于数字图像解卷积是典型的解线性方程组的问题,用雅可比(Jacobi)迭代法得到了很好的结果。与频谱空间变换的方法相比,迭代法没有分母为0的问题和空间变换过程造成的舍入误差。 相似文献
29.
Summary The influence of draw ratio on macroscopic and crystallographic density of polyethylene with different initial morphologies, has been investigated by solid-state extrusion. An initial drop followed by an increase in macroscopic density as a function of draw ratio has been observed. Since precision X-ray measurements of unit cell parameters showed no variation of crystallographic density, it was concluded that plastic deformation of polyethylene upon drawing proceeds with a decrease of the degree of crystallinity. This was confirmed by differential scanning calorimetry. 相似文献
30.
From visual data exploration to visual data mining: a survey 总被引:8,自引:0,他引:8
Ferreira de Oliveira M.C. Levkowitz H. 《IEEE transactions on visualization and computer graphics》2003,9(3):378-394
We survey work on the different uses of graphical mapping and interaction techniques for visual data mining of large data sets represented as table data. Basic terminology related to data mining, data sets, and visualization is introduced. Previous work on information visualization is reviewed in light of different categorizations of techniques and systems. The role of interaction techniques is discussed, in addition to work addressing the question of selecting and evaluating visualization techniques. We review some representative work on the use of information visualization techniques in the context of mining data. This includes both visual data exploration and visually expressing the outcome of specific mining algorithms. We also review recent innovative approaches that attempt to integrate visualization into the DM/KDD process, using it to enhance user interaction and comprehension. 相似文献