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91.
OBJECTIVE: To assess whether patients with pancreatic cancer-associated pain living near a pain control center were more likely to undergo neurolytic celiac plexus block (NCPB) than those living at a distance and to determine the rationale of physicians at our institution for referring patients for NCPB. DESIGN: We retrospectively reviewed the frequency of use of NCPB in patients with pancreatic cancer and conducted an anonymous physician survey of referral patterns for NCPB for such patients. MATERIAL AND METHODS: A prospective database of medical diagnoses and a clinical database at our institution were used to identify patients with pancreatic cancer within three geographic regions who were assessed during the inclusive years 1980 through 1989: group I ("local") = all patient with pancreatic cancer in Olmsted County, Minnesota; group II ("surrounding") and group III ("distant") = patients referred for pancreatic cancer evaluation who lived within 100 miles of our institution (excluding Olmsted County) or more than 100 miles from our institution, respectively. Medical records were retrospectively reviewed to assess the use of NCPB at any time during the course of pancreatic cancer. For the physician survey component, all medical oncologists, gastroenterologists, and general surgeons at our institution who might be responsible for the care of patients with pancreatic cancer were sent a questionnaire about their referral patterns for NCPB among patients with pancreatic cancer. RESULTS: Overall, approximately 15% of the 292 patients with pancreatic cancer studied underwent NCPB. Distance from our pain control center was not found to be associated with frequency of use of NCPB. Of the 78 physicians surveyed, 59 (76%) responded, and 35 of the responders (59%) had encountered at least 1 patient with pancreatic cancer during the preceding 12 months. In that subset of physicians, perceived barriers for referral for NCPB were limited appointment availability and need for repeating the procedure. CONCLUSION: On the basis of this study, referral patterns for NCPB in patients with pancreatic cancer do not seem to be associated with the geographic distance of a patient's residence from a pain control center. Improving appointment availability for NCPB might increase the number of patients offered this technique for control of pain.  相似文献   
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OBJECTIVES: This study was undertaken to explore smoking patterns and attitudes that influence smoking cessation and relapse among African Americans. METHODS: Baseline data from eight Community Intervention Trial for Smoking Cessation (COMMIT) sites were analyzed. RESULTS: Compared with Whites, African Americans who smoke less than 25 cigarettes per day were 1.6 times more likely to smoke within 10 minutes of awakening (a behavioral indicator of nicotine dependence), adjusting for education, age, and gender (OR = 1.2 for heavier smokers). African Americans reported a stronger desire to quit smoking and reported serious quit attempts in the past year. African Americans favored tobacco restrictions (they were 1.8 times more likely than Whites to view smoking as a serious community problem, 1.7 times more likely to favor restrictions on cigarette vending machines, and 2.1 times more likely to prohibit smoking in their car). African Americans were lighter/moderate, menthol smokers. CONCLUSIONS: African Americans find smoking socially unacceptable and are strongly motivated to quit, but their "wake-up" smoking may indicate high nicotine dependence, making abstinence difficult even for lighter smokers.  相似文献   
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In response to threats posed to the future supply of energy and to the environment, the G8 leaders, in Gleneagles, UK in 2005, agreed to an initiative called the Gleneagles Plan of Action (GPOA) which addresses climate change, clean energy and sustainable development. In the GPOA, G8 leaders pledged to encourage the development of cleaner, more efficient and lower-emitting vehicles, and to promote their deployment by, among other means, asking the IEA to review existing standards and codes for vehicle efficiency and to identify best practices.  相似文献   
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Urea (CO(NH2)2) and its related compounds (biuret: NH(CONH2)2 and cyanuric acid: (CONH)3) were mixed with phosphoric acid (H3PO4) and neodymium oxide (Nd2O3). The thermal behavior of these dried mixtures was estimated by differential thermal analyses, X-ray diffraction, and Fourier-transform infrared spectroscopy. Furthermore, specific surface area of phosphates was calculated by BET method using nitrogen adsorption. The addition of urea prevented the crystal growth of Monazite-type NdPO4 in samples at P/Nd = 2 heated at 450 and 550 °C, and promoted the dehydration–condensation reaction of phosphate. Urea was considered to be decomposed at 400–450 °C in these systems. The decomposition of urea was considered to be related to the formation of neodymium dihydrogenphosphate and then this phosphate transformed to neodymium polyphosphate. The ratio of urea and phosphorus had influence on the promotion of the dehydration–condensation reaction. Thermal behavior of sample added with biuret or cyanuric acid was also investigated.  相似文献   
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This paper describes the effect of a barrier on creeping discharge characteristics in SF6, N2, and their mixtures. The barrier height effect on the discharge voltage was investigated under a positive pulse voltage. The discharge voltage increased with increasing barrier height in SF6 gas. On the other hand, the discharge voltage hardly changed with the barrier height in N2 gas. In order to clarify the mechanism of the initial creeping corona, it was observed by optical techniques, including an ultra-high-speed electronic imaging system (IMACON 468). The creeping corona path revealed differences in images at various barrier heights. The accumulated charge induced on the barrier by the initial corona in SF6 gas was able to suppress the development of the later creeping corona, in contrast with N2 gas. © 1998 Scripta Technica, Electr Eng Jpn, 125(4): 1–8, 1998  相似文献   
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Eleven cases of salivary duct carcinoma were studied clinicopathologically. The clinical features are as follows: men outnumber women; arise most frequently within the parotid glands; rapidly enlarging mass; obvious symptoms of invading nerves; high rates of cervical lymph node and distant metastases; poor patient's prognosis. Its histologic features were shown by the various stages of development of duct carcinoma including dysplasia, carcinoma in situ, papillary, cribriorm, solid and commedo patterns. In addition to the intraductal carcinoma, there is the invasive carcinoma with obvious infiltration into the surrounding tissues. Its treatment requires the combination of radical surgery with postoperative radiotherapy.  相似文献   
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