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91.
OBJECTIVE: To evaluate the chemical composition and crystalline structures of Portland cement, gray ProRoot MTA (gray MTA), white ProRoot MTA (white MTA), and gray MTA-Angelus. STUDY DESIGN: X-ray diffraction analysis was used to identify and characterize crystalline phases, and energy dispersive x-ray spectrometer was used to determine the chemical composition of the test materials. Both powder form and set form were examined. RESULTS: The crystalline structure and chemical composition of gray and white MTA were similar except for the presence of iron in gray MTA. Both were composed mainly of bismuth oxide and calcium silicate oxide. Portland cement was composed mainly of calcium silicate oxide and did not contain bismuth oxide. Gray MTA-Angelus had a lower content of bismuth oxide than ProRoot MTA. There were no noticeable differences in the chemical composition and crystalline structures between the powder and set forms of any of the material tested. CONCLUSION: Portland cement differed from the MTA by the absence of bismuth ions and presence of potassium ions. Gray MTA contained a significant amount of iron when compared with white MTA. In addition, gray MTA-Angelus had a lower content of bismuth oxide than ProRoot MTA.  相似文献   
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PURPOSE: Acute pain management services (APMS) evolved in response to the desire for improved management of postoperative pain. The management of postoperative pain received formal support from international organizations over the past decade and by 1993 half of the Canadian university-affiliated teaching hospitals had implemented an APMS. The purpose of this survey was to describe APMSs in Canadian academic institutions, with specific emphasis on postoperative analgesics, new analgesic methods, training and research. METHODS: Between June 2000 and January 2001, 62 Canadian hospitals affiliated with the 16 Canadian university anesthesiology departments were sent a postal questionnaire. RESULTS: Fifty of the 62 respondents returned a completed questionnaire representing a response rate of 81%. Eighty percent of the hospitals surveyed had at least 200 beds, 90% (45) had implemented an APMS. Anesthesiology was primarily responsible in all 45 hospitals with an APMS. The results presented are based on the 45 centres with an APMS. CONCLUSION: Since the early 1990s the percent of Canadian academic hospitals with an APMS has increased from 53% to 92%. These figures are comparable to the United States. Greater collaboration from nursing and pharmacy, mandatory training for medical and nursing students and residents, and a standardized approach to continuous quality improvement remain necessary.  相似文献   
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Throughout history, the heart has been associated not only with its life-sustaining function but also with its close ties to the human emotions. In this literature and internet review, we attempt to gather and organize information from both of these perspectives as they relate to the heart in the following 11 categories: (1) fun facts, (2) medical photography, (3) history, (4) languages (etymology), (5) nonmedical English expressions, (6) death, (7) the arts, (8) movie titles, (9) song titles, (10) Shakespeare, and (11) the Bible. Part 1 (previously published) covered the first five topics, and Part 2 will cover the last six topics. These data may be useful to those who are engaged in teaching about the cardiovascular system.  相似文献   
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Absidia corymbifera infection in a healthy individual is rare. Most of the infection occurs in immunocompromised patients or diabetic patients. Cutaneous and subcutaneous mucormycosis have been increasingly reported in the literature as a result of massive trauma with contaminated wounds. We present a case of cutaneous mucormycosis in a healthy, young patient after surgical amputation for a crush injury of the leg. We also highlight the importance of the high index of clinical suspicion in the diagnosis and treatment of this fungal infection in the hype of methicillin-resistant Staphylococcus aureus (MRSA) infection in hospital setting these days. Despite an initial life-saving amputation, it was inadequate to ensure the eradication of A. corymbifera infection. A second amputation was required with parenteral liposomal amphotericin B to achieve a satisfactory cure.  相似文献   
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