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Background: The effects of epidural needle design, angle, and bevel orientation on cerebrospinal fluid leak after puncture have not been reported. The impact of these factors on leak rate was examined using a dural sac model. Dural trauma was examined using scanning electron microscopy.

Methods: Human cadaveric dura, mounted on a cylindrical model, was punctured with epidural needles using a micromanipulator. Tissue was punctured at 15 cm H2O (left lateral decubitus) system pressure, and leak was measured at 25 cm H2O (semisitting) pressure. Leak rates and trauma were compared for the following: (1) six different epidural needles at 90[degrees], bevel parallel to the dural long axis; (2) 18-gauge Tuohy and 18-gauge Special Sprotte(R) epidural needles, 30[degrees]versus 90[degrees]; (3) 18-gauge Tuohy, bevel perpendicular versus parallel to the dural long axis.

Results: With the 90[degrees] puncture, bevel parallel, the greatest leak occurred with a 17-gauge Hustead (516 +/- 319 ml/15 min), and the smallest leak occurred with a 20-gauge Tuohy (100 +/- 112 ml/15 min; P = 0.0018). A 20-gauge Tuohy puncture led to statistically significant reductions in leak (P value range, 0.0001-0.0024) compared with all needles except the Special Sprotte(R). With the 30[degrees]versus 90[degrees] angle, 30[degrees] punctures with an 18-gauge Tuohy produced nonstatistically significant leak reductions compared with the 18-gauge Tuohy at 90[degrees]. The puncture angle made no difference for the Special Sprotte(R). Nonsignificant reductions were found for the Special Sprotte(R) compared with the Tuohy. With the 18-gauge Tuohy bevel orientation, perpendicular orientation produced nonstatistically significant reductions in leak compared with parallel orientation.  相似文献   

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A review of the international literature on staffing in childcare centres in five English language countries and Denmark reveals both remarkable similarities and interesting differences in the childcare workforce. The paper compares characteristics of the workforce; their training and professional membership. It also compares conditions of work in each country, including salaries, staff benefits, and features of the working environment such as job satisfaction and staff turnover. Findings indicate that childcare workers tend to be young and female; that a relatively high proportion of untrained staff work in childcare centres; that, except in Denmark, the level of extrinsic benefits is startlingly low. Workers are paid relatively little compared to the average pay for women in their countries but the workforce does not benefit from enhanced conditions of work to compensate for low pay. However, the level of intrinsic satisfaction with the work is high. Caring for children is a satisfying form of employment, even if it offers a limited career structure.  相似文献   
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Students (N = 377) from four Cape Town township high schools were surveyed to obtain information on their knowledge of and attitudes towards the acquired immunodeficiency syndrome (AIDS), and on their sexual behaviour. The study was undertaken to provide information for planning an AIDS education intervention. Three-quarters of students reported that they had had sexual intercourse. Most students had heard of AIDS, and the majority of these knew that it was infectious. More than half of the students were confused or lacked knowledge about the modes of transmission. Two-thirds of the students believed AIDS could be prevented, but knowledge of prevention strategies was superficial. Of the sexually active students only 11.4% had ever used a condom, and of all students 39.6% stated that they would use a condom in the future. Two-thirds of the students were not aware that there is no cure for AIDS. Students did not acknowledge that AIDS could affect them directly, and attributed the problem to prostitutes and 'promiscuous' people in 36.4% of responses, and to 'white' people in 23.8% of responses. Students expressed intolerance, fear and rejection of people with AIDS, and only 6.4% would accept an affected person into their class. Almost all the students wanted AIDS education at school, and most of these requested that the school nurse facilitate this education. It is concluded that appropriate AIDS prevention education is urgently required for both high school and junior school students.  相似文献   
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This data would suggest that psychiatric training programs may not be organized according to the interest or needs of many trainees. The emphasis on fulltime research in neurobiological psychiatry is centre stage in most programs, and yet according to our survey, few residents view this as a desirable career path. Our data from 8 years of trainees at the University of Toronto indicates that a new model of training streams would best suit the needs of the trainee, the profession and the community. This report is a continuation of a study into the recruitment process. An earlier report was published in the Canadian Journal of Psychiatry Vol. 29, December 1984. Our present data is on two groups of trainees as well as from faculty.  相似文献   
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