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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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Performance characteristics and image fidelity of gray-scale monitors.   总被引:2,自引:0,他引:2  
Gray-scale monitors are an essential element of electronic radiology, and their ability to provide images that are perceived to be identical to those available on conventional or laser-printed film is crucial to success of electronic radiology. Image fidelity is measured in physical characteristics (luminance, dynamic range, distortion, resolution, and noise) and with psychophysical techniques, including receiver operator characteristics analysis with clinical images and testing with contrast-detail patterns to determine threshold contrast. Currently, laser-printed images facilitate greater information transfer than does a gray-scale monitor because of their higher absolute luminance (500 ft-L vs 60 ft-L), greater perceived dynamic range, and better spatial resolution. In the near future, the developments of gray-scale monitors with 150-200 ft-L luminance, a display standard based on just noticeable differences, and algorithms to improve similarities between gray-scale display images and laser-printed images will help increase the acceptability of monitors as a means to make primary diagnoses.  相似文献   
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Human adenocarcinoma (AC) is the most frequently diagnosed human lung cancer, and its absolute incidence is increasing dramatically. Compared to human lung AC, the A/J mouse-urethane model exhibits similar histological appearance and molecular changes. We examined the gene expression profiles of human and murine lung tissues (normal or AC) and compared the two species' datasets after aligning approximately 7500 orthologous genes. A list of 409 gene classifiers (P value <0.0001), common to both species (joint classifiers), showed significant, positive correlation in expression levels between the two species. A number of previously reported expression changes were recapitulated in both species, such as changes in glycolytic enzymes and cell-cycle proteins. Unexpectedly, joint classifiers in angiogenesis were uniformly down-regulated in tumor tissues. The eicosanoid pathway enzymes prostacyclin synthase (PGIS) and inducible prostaglandin E(2) synthase (PGES) were joint classifiers that showed opposite effects in lung AC (PGIS down-regulated; PGES up-regulated). Finally, tissue microarrays identified the same protein expression pattern for PGIS and PGES in 108 different non-small cell lung cancer biopsies, and the detection of PGIS had statistically significant prognostic value in patient survival. Thus, the A/J mouse-urethane model reflects significant molecular details of human lung AC, and comparison of changes in orthologous gene expression may provide novel insights into lung carcinogenesis.  相似文献   
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Early dental caries detection will facilitate implementation of nonsurgical methods for arresting caries progression and promoting tooth remineralization. We present a method that combines optical coherence tomography (OCT) and Raman spectroscopy to provide morphological information and biochemical specificity for detecting and characterizing incipient carious lesions found in extracted human teeth. OCT imaging of tooth samples demonstrated increased light backscattering intensity at sites of carious lesions as compared to the sound enamel. The observed lesion depth on an OCT image was approximately 290 microm matching those previously documented for incipient caries. Using Raman microspectroscopy and fiber-optic-based Raman spectroscopy to characterize the caries further, spectral changes were observed in PO4 (3-) vibrations arising from hydroxyapatite of mineralized tooth tissue. Examination of various ratios of PO4 (3-) nu2, nu3, nu4 vibrations against the nu1 vibration showed consistent increases in carious lesions compared to sound enamel. The changes were attributed to demineralization-induced alterations of enamel crystallite morphology and/or orientation. OCT imaging is useful for screening carious sites and determining lesion depth, with Raman spectroscopy providing biochemical confirmation of caries. The combination has potential for development into a new fiber-optic diagnostic tool enabling dentists to identify early caries lesions with greater sensitivity and specificity.  相似文献   
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