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71.
PURPOSE: The objective of this survey was to examine the services offered by multidisciplinary pain treatment facilities (MPTFs) across Canada and to compare access to care at these MPTFs. METHODS: A MPTF was defined as a clinic that advertised specialized multidisciplinary services for the diagnosis and management of patients with chronic pain, having a minimum of three different health care disciplines (including at least one medical speciality) available and integrated within the facility. The search method included approaching all hospital and rehabilitation centre administrators in Canada, the Insurance Bureau of Canada, the Workplace Safety and Insurance Board or similar body in each province. Designated investigators were responsible for confirming and supplementing MPTFs from the preliminary list for each province. Administrative leads at each eligible MPTF were asked to complete a detailed questionnaire regarding their MPTF infrastructure, clinical, research, teaching and administrative activities. RESULTS: Completed survey forms were received from 102 MPTFs (response rate 85%) with 80% concentrated in major cities, and none in Prince Edward Island and the Territories. The MPTFs offer a wide variety of treatments including non-pharmacological modalities such as interventional, physical and psychological therapy. The median wait time for a first appointment in public MPTFs is six months, which is approximately 12 times longer than non-public MPTFs. Eighteen pain fellowship programs exist in Canadian MPTFs and 64% engage in some form of research activities CONCLUSION: Canadian MPTFs are unable to meet clinical demands of patients suffering from chronic pain, both in terms of regional accessibility and reasonable wait time for patients' first appointment.  相似文献   
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The use of a skeletonized internal thoracic artery in coronary artery bypass graft surgery has been shown to confer certain advantages over a traditional pedicled technique, particularly in certain patient groups. Recent reports indicate that radial and gastroepiploic arteries can also be harvested using a skeletonized technique. The aim of this study is to systematically review the available evidence regarding the use of skeletonized radial and gastroepiploic arteries within coronary artery bypass surgery, focusing specifically on it's effect on conduit length and flow, levels of endothelial damage, graft patency and clinical outcome. Four electronic databases were systematically searched for studies reporting the utilisation of the skeletonization technique within coronary revascularisation surgery in humans. Reference lists of all identified studies were checked for any missing publications. There appears to be some evidence that skeletonization may improve angiographic patency, when compared with pedicled vessels in the short to mid-term. We have found no suggestion of increased complication rates or increased operating time. Skeletonization may increase the length of the conduit, and the number of sequential graft sites, but no clear clinical benefits are apparent. Our study suggests that there is not enough high quality or consistent evidence to currently advocate the application of this technique to radial or gastroepiploic conduits ahead of a traditional pedicled technique.  相似文献   
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OBJECTIVE: To investigate the presence and features of short-interval intracortical inhibition (SICI) in the human trigeminal motor system. METHODS: Surface electromyogram (EMG) was recorded from left and right digastric muscles in 7 subjects, along with additional experiments with intramuscular EMG in 2 subjects. Focal transcranial magnetic stimulation (TMS) was used to activate the motor cortex of one hemisphere and elicit motor evoked potentials (MEPs) in digastric muscles on each side, at rest and while subjects activated the muscles at 10% maximal EMG. Paired or single TMS pulses were delivered in blocks of trials, while conditioning TMS intensity and interstimulus interval (ISI) were varied. RESULTS: At rest, paired TMS (3-ms ISI) with conditioning intensities 0.8-0.9x active motor threshold (TA) reduced the digastric MEP amplitude to a similar extent bilaterally. Conditioning at 0.5-0.7TA did not significantly reduce the MEP. MEP amplitude was reduced to a similar extent in both digastric muscles by ISIs between 1 and 4 ms (0.8TA). Voluntary bilateral activation of digastric muscles reduced the effectiveness of conditioning TMS compared to the resting state, with no differences between sides. The similarity of the responses in both digastric muscles was not due to EMG cross-talk (estimated to be approximately 10% in surface records and approximately 2% in intramuscular records), as the intramuscular records showed the same pattern as the surface records. CONCLUSIONS: The effects of paired-pulse TMS on digastric are similar to those reported for contralateral hand muscles, and are consistent with activation of SICI circuits in M1 by conditioning TMS. Our evidence further suggests that the corticomotor representations of left and right digastric muscles in M1 of a single hemisphere receive analogous inhibitory modulation from SICI circuits. SIGNIFICANCE: SICI has been demonstrated in the face area of motor cortex controlling the trigeminal motor system in normal subjects. This method can be used to investigate abnormalities of SICI in movement disorders affecting the masticatory muscles in humans.  相似文献   
76.
The purpose of this study was to determine the attitudes of Chinese dental students and dental surgery assistants toward disabled persons using the Scale to Determine Attitudes Toward Disabled Persons, the SADP. A group of 99 Hong Kong University psychology students, 50 male and 49 female, was used as the control and to determine the internal consistency and reliability of the Chinese version of the scale. A group of 4th year (n = 25) and a group of 3rd year (n = 46) dental students and a group of in-house dental surgery assistants (n = 86) at the Prince Philip Dental Hospital, Hong Kong, were asked to complete a Chinese translation of the SADP. Results showed that there was no significant difference between attitude scores of 3rd and 4th year dental students (p = 0.06). There was a significant difference in attitude scores between dental students and the dental surgery assistants (p < O.OOl), with those of dental students being lower. In the control group, there was no significant difference between female control and dental surgery assistant scores (p = 0.289). There was a significant difference between dental students and male control scores (p < 106). Not only did the dental students score lower than the dental surgery assistants, but they also scored significantly lower than a group of non-dental students of the same University.  相似文献   
77.
The effect of sodium lauryl sulphate (SLS) on cytokeratin (CK) gene expression in hamster cheek pouch epithelium was studied with a hybridohistochemical technique. Using specific human anti-sense RNA probes, the plausible hamster mRNA counterparts for these human CK mRNAs were localized by detection of heterologous hybrids. In comparison with normal epithelium, the expression and distribution pattern of CK mRNAs in the hamster cheek pouch were obviously changed after application of SLS. There was a decreased expression of CK mRNAs in the hyperplastic basal layer, and increased expression in the hypertrophic granular layer. Strikingly, hybridization with the human CK 18 cRNA probe revealed an additionally expressed CK mRNA in the SLS-treated epithelium that was not found in the untreated epithelium. The present study indicates that cRNA probes for human CK mRNAs can be used successfully, not only to distinguish between different hamster CK mRNAs but also to investigate changes in CK gene expression upon the induction of non-neoplastic and neoplastic alterations in the hamster cheek pouch model. This may help elucidate the molecular changes involved in epithelial pathologies.  相似文献   
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The visit of Dr. Trendley Dean to Dublin in the mid-1950s helped accelerate the decision to introduce water fluoridation as a public health measure in the prevention of caries in the Republic of Ireland. A challenge to the constitutional validity of the Health (Fluoridation of Water Supplies) Act 1960 failed and in 1964 the water supplies of Dublin city were fluoridated. Over the next seven to eight years all the major urban communities in the Republic of Ireland were fluoridated. Currently, 67 percent of the 3.5 million people in the country reside in fluoridated communities. Studies conducted over the last 20 years show that residents of fluoridated communities have better dental health than those in nonfluoridated communities—the mean dmft is lower in children and the number of natural teeth present in adults is higher.  相似文献   
80.
OBJECTIVES: Leakage around retrograde fillings is an important cause of endodontic surgery. This in vitro study sought to compare the following: (1) methylene blue dye leakage linked to retrofillings in human and sheep teeth with the degree of dye penetration when intermediate restorative materials and Chemfil were used as retrofillings, (2) the apical microleakage in filled with that in unfilled root canals, and (3) 2 storage techniques, incubator-based and subcutaneous implantation in rats. STUDY DESIGN: Tested were 198 human and 196 sheep teeth that were retrofilled with intermediate restorative material or Chemfil, then stored in an incubator or subcutaneously in rats for 10, 20, and 30 days before immersion in methylene blue dye for 24 hours. Linear dye penetration was evaluated, and the results were statistically analyzed by means of analysis of variance. RESULTS: Leakage between sheep and human teeth was significantly different (P <.05). Chemfil had significantly less leakage than intermediate restorative material after storage in rat (P <.05) for up to 20 days, but not after 30 days. No differences were found between leakage of unfilled and filled human root canal teeth. CONCLUSIONS: The sheep incisor is a poor experimental model of the human tooth, and both aging procedures demonstrate extensive leakage of retrofilling materials after long-term storage.  相似文献   
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