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ABSTRACT

The gold work from the Western European Middle and Late Bronze Age (about 1500–700 BC) is characterized by solid ornaments and vessels. This article deals with manufacturing techniques of heavy gold jewelry by presenting a gold hoard found at Guînes, Pas-de-Calais, in Northern France, as a case study. In particular, three ornament types will be taken into consideration: (1) solid penannular neck and arm-rings, plain or with linear or geometric decoration; (2) flange-twisted ornaments that appear in different dimensions, as small as ear rings, as neck rings, up to the large size of a belt; (3) complex, composite ornaments. The technological aspects dealt with in this precious metal working context are manifold, including ingot and lost wax casting, hammering and bending of solid rods, the production of flange-twisted rods, chasing as decoration method, and finally joining techniques such as soldering, riveting and folding, and creasing.  相似文献   
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BACKGROUND/AIMS: Colonic involvement is a rare but serious event in necrotizing pancreatitis. Early detection of this complication is difficult; a delay of diagnosis may lead to perforation and peritonitis. Two strategies of therapy have been developed in the last few years: an aggressive regimen of early resection and a conservative approach with ileostomy and observation. MATERIALS AND METHODS: Fourteen of 118 patients treated for necrotizing pancreatitis from 1988 to 1995 presented with colonic necrosis. The diagnosis of necrosis was made if the color of the bowel wall demonstrated ischemia or hemorrhagic infarction or pulsations of the mesocolic vessels could not be palpated. The first two patients were treated by a conservative approach the following 12 by immediate large bowel resection. Follow-up results of all surviving patients were obtained. RESULTS: Patients with colonic lesions demonstrated an advanced septic state compared to patients who did not present this complication. Differences in the average Apache 2 scores on admission and the incidence of multiple organ failure were significant (Apache 2 score; 16.6 versus 11.9, p = 0.028, Wilcoxon; multiple organ failure; 71% versus 35%, p = 0.028, Fisher's exact test). Results after establishment of early discontinuity-resection of colonic necrosis compared favorably to those of a conservative strategy (mortality 4/12; 33% versus 2/2; 100%). The overall mortality was 43% (6 of 14 patients). Restorative surgery was performed in 6 patients without substantial morbidity and no mortality. Follow-up results were satisfactory in the majority of the patients. CONCLUSIONS: Early resection of colonic lesions improves results in this dangerous complication of necrotizing pancreatitis.  相似文献   
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A new setup is presented which enables simultaneous wide- and small-angle X-ray scattering (WAXS/SAXS) and Raman spectroscopic experiments during the synthesis of Mo-based mixed oxide catalyst precursors at the μ-spot beamline at the Berliner Elektronenspeicherring-Gesellschaft für Synchrotronstrahlung (BESSY). Furthermore, we report about the separate monitoring of the same reactions under comparable conditions by simultaneous combined ATR/UV–vis/Raman spectroscopic measurements. For testing the performance of both experimental setups two syntheses were described comprising the precipitation of metal molybdates by mixing solutions of metal nitrates and ammonium heptamolybdate. Additionally, the effect of H3PO4 admixture on precipitation was investigated. The combined evaluation of spectroscopic and WAXS/SAXS data allows the discrimination between different molybdate species appearing in solution and precipitate. Furthermore, these molybdate species could be assigned to separate phases of different crystallinity.  相似文献   
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BACKGROUND: Although gastric bypass is an effective treatment for morbid obesity, the postoperative results are unsatisfactory in 10% of all patients. Therapeutic failures after an operation performed with the sole purpose of reducing the risk of obesity-associated diseases have to be taken seriously. The goal of this study was to investigate the causes of these failures. METHOD: From 1979 to 1993, 165 gastric bypass operations (technique: Mason-Griffen) were performed. Long-term results were obtained in 60 patients after an average of 6.6 years (range 3-13). On follow-up all patients were examined and asked about their level of satisfaction with the weight loss achieved and changes in eating habits. RESULTS: In 6 patients the weight reduction was regarded as insufficient (BMI > 35 and reduction of BMI < 10). The causes of these failures were technical in 3 cases (gastric pouch to 0 large in 1, dilatation of gastrojejunostomy in 2). Three patients had a high calorie intake through an intact gastric bypass by snacking. Three patients regarded the operation as a failure although they had achieved significant weight loss, because they could no longer eat the usual amounts of food. CONCLUSION: Correct surgical technique and preoperative information on the changes in eating habits after a gastric bypass operation are the most important steps in preventing therapeutic failures.  相似文献   
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An Essix intrusion appliance   总被引:1,自引:0,他引:1  
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The authors discuss the classification of a large variety of multimedia communication applications (with the emphasis on broadband and hypermedia applications), the requirements at network levels, multimedia communications concepts with suitable platforms, and the modular standardization of multimedia teleservices and the corresponding technical systems. Appropriate technologies for meeting multimedia requirements comprise public and private networks, servers for information storage and processing, intelligent user and system agents, and multimedia terminals, e.g., workstations. The authors deal with the question of service-specific or service-integrated networks, the architecture, components, and functions of asynchronous transfer model (ATM) switching systems for broadband ISDN and ATM-based signaling, and management for controlling connectivity and interactivity. Network evolution, pilot applications, and coordinated standardization are briefly considered  相似文献   
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Malignant hyperthermia developed in two Landrace x Large White pigs, 75 and 105 minutes after the induction of anaesthesia with halothane. Rapid treatment and discontinuation of halothane anaesthesia were unable to reverse the condition in the first case but were successful in the second. The delayed onset of malignant hyperthermia after delivery of halothane is unusual and for successful treatment careful monitoring and rapid and aggressive therapy are needed.  相似文献   
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