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EM de Jong BA Seegers MK Gulinck JB Boezeman PC van de Kerkhof 《Canadian Metallurgical Quarterly》1996,193(4):300-303
We present the first case of esophagogastric devascularization and esophagogastric transection using a stapler through laparoscopic surgery. The procedure was performed in a 71-year-old diabetic woman with alcoholic liver cirrhosis (Child-Pugh B class), portal hypertension, bleeding grade III esophageal varices, and a previous bleeding episode. The surgical technique was carried out without problems, and the patient had an excellent postoperative condition. Esophagogastric devascularization with esophageal transection using a stapler through laparoscopic surgery is a feasible technique that accomplishes the same and all objectives of the open procedure. Operative time in both methods is the same, whereas surgical trauma, inmunologic depletion, amount of transfused blood, pain, use of analgesics, and hospital stay are reduced in the laparoscopic technique. 相似文献
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B Cockeram A G Jackson R E Omlor R Srinivasan I Weiss 《Microscopy research and technique》1992,22(3):298-300
Ductile phase toughened composites contain phases with significantly different physical properties. Consequently, these phases thin at different rates depending on the sample preparation procedure. A new TEM foil preparation method for the ductile phase toughened Nb-10 a/o Si material has been developed. The method involves chemical thinning in a 70% nitric acid/30% hydrofluoric acid solution followed by electropolishing in a 12.5% sulfuric acid/87.5% methanol electrolyte at -40 degrees C. This procedure for making TEM foils results in large thin areas with the minimum of artifacts. Mechanical grinding of a sample followed by either ion milling, dimpling, or electropolishing produced foils with large electron transparent areas, but with uncharacteristic features of the original Nb-10 a/o Si alloy microstructure. These artifacts were identified as dislocations, surface mottling, and antiphase domains. 相似文献
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Quaternary ammonium salts of sulfonated polystyrene (SPS) were used as compatibilizers for melt intercalation of PS and pristine Na-montmorillonite. Tetra-octyl ammonium SPS and tetra-decyl ammonium SPS ionomeric compatibilizers produced significant exfoliation and a homogeneous dispersion of the polymer-clay nanocomposites. Wide angle X-ray diffraction and transmission electron microscopy were primarily used to characterize the morphology of the nanocomposites. Image analysis was used to measure the percentage exfoliation. Exfoliation increased with the increasing length of the alkyl chain of the ammonium counter-ion of the SPS ionomer. The nanocomposites containing ionomers exhibited higher storage moduli compared to nanocomposites without the compatibilizer. 相似文献
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The authors describe their perspectives as a psychologist married couple and discuss some of the major trends that have affected their work in the last years, including the women's movement and new developments in the field of psychology. They note both positive and negative changes from the last 2 decades. Whereas there are many more new and exciting opportunities for psychologists today, there are also more pressures, more stringent training and credentialing requirements, more competition, and less mobility. Also discussed are some advantages to being married to another psychologist, including understanding each other's roles, combining social and professional lives, and expanding professional networks. They look to the future of psychology with optimism and hope that by examining and changing some of the restrictions on psychologists today, the field of professional psychology can be made more rewarding for future psychologists. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献