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排序方式: 共有874条查询结果,搜索用时 15 毫秒
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744.
DC Crawford 《Journal of medical engineering & technology》2013,37(3):108-111
The evaluation of medical devices in the UK has been through many changes since the early hospital equipment assessments in the 1960s. The range of medical devices evaluated has increased and the evaluation reports published have changed, but the evaluation programme continues to be a respected service for the NHS and social care. This review documents the history of the Device Evaluation Service, from its beginnings to the present day, and looks forward to its future. Following an independent strategic review and the Healthcare Industries Task Force (HITF) recommendations, the Device Evaluation Service is now entering a new and exciting developmental phase. 相似文献
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BACKGROUND CONTEXT: A number of recent scientific publications suggest that patients suffering from whiplash-associated disorders (WADs) exhibit sensorimotor deficits in the control of head and neck movements. PURPOSE: The main objective of the present study was to evaluate if subjects with WADs can produce isometric neck extension and flexion forces with precision, variability, and a mode of control similar to the values of healthy subjects. STUDY DESIGN: A control group study with repeated measures. PATIENT SAMPLES: Neck force production parameters and neuromuscular control were measured in 17 whiplash and 14 control subjects. The experimental group included subjects who had a history of persistent neck pain or disability after a motor vehicle accident. OUTCOME MEASURES: Pain levels were assessed on a standard 100-mm visual analog pain scale at the beginning and end of the experiment. Each whiplash subject completed the neck disability index and the short-form 36 health survey (SF-36) questionnaire before the experiment. METHODS: All subjects were asked to exert flexion and extension forces against a fixed head harness. Kinetic variables included time to peak force, time to peak force variability, peak force variability, and absolute error in peak force. Surface electrodes were applied bilaterally over the sternocleidomastoideus and paraspinal muscles. Electromyography (EMG)-dependent variables included EMG burst duration and amplitude using numerical integrated techniques. RESULTS: The average time to peak force was significantly longer for whiplash subjects than for the healthy controls. A significant increase in peak force variability was also observed in the whiplash group, and no group differences were noted for absolute error. Heightened muscular activity was seen in both paraspinal muscles, even though it only reached statistical significance for the left paraspinal muscle. CONCLUSION: Our results show that the whiplash subjects involved in the study were able to produce isometric forces with spatial precision similar to healthy controls using a motor strategy in which the time to peak force is increased. This trade-off between spatial precision and time to peak force probably reflects an adaptation aimed at limiting pain and further injuries. 相似文献
747.
J Lin G S Markowitz M Nicolaides C S Hesdorffer G B Appel V D D'Agati D G Savage 《American journal of nephrology》2001,21(5):351-356
We report two cases of nephrotic syndrome presenting 18 and 20 months after allogeneic stem cell transplantation (alloSCT) with chronic myelogenous leukemia. Both patients had acute and chronic graft-versus-host disease (GVHD) and renal biopsy findings of membranous glomerulopathy (MG). A review of the literature revealed 10 additional cases of immune-complex-mediated glomerular disease following alloSCT, 8 of which were diagnostic of MG. All patients showed evidence of acute or chronic GVHD. Patients typically presented with preserved renal function (mean creatinine 1.2 mg/dl) and full nephrotic syndrome including heavy proteinuria (mean 9.2 g/24 h), edema, hypoalbuminemia (mean 2.1 g/dl) and hypercholesterolemia (mean 472 mg/dl). Most patients showed stabilization of renal function and significant decreases in proteinuria when treated with steroids and/or cyclosporine. The close temporal association as well as evidence from murine models of GVHD support a pathogenetic association between GVHD and the development of MG. 相似文献
748.
某经济开发区1991~1997年383起工伤死亡事件调查分析 总被引:12,自引:2,他引:10
调查分析工业企业致死工伤的环境危害因素。(方法)对某开发区1991 ̄1997年间发生的383起工伤死亡事件进行了流行病学调查分析。(结果)发现(1)由于许多基建工程项目于1993 ̄1995年批准并实施或完成,这些工伤死亡事件大多发生于1994年和1995年;(2)事故常发生在周末加班时且可能有急于完成某一任务而赶时间的倾向;(3)坠落、起重伤害、物体打击、触电和坍塌是最常见(89%)的伤害方式,它 相似文献
749.
Wayne Whittingham DC PhDa Niels Nilsson DC MD PhDb 《Journal of manipulative and physiological therapeutics》2001,24(9):552-555
BACKGROUND: It has generally been assumed that spinal manipulation has the biomechanical effect of increasing spinal range of motion. Past research has shown that there are likely no lasting changes to passive range of motion, and it is unclear whether there is an increase in active range of motion after manipulation. OBJECTIVE: To study changes in active cervical range of motion after spinal manipulation of the cervical spine. DESIGN: A double-blind randomized controlled trial at the outpatient clinic Phillip Chiropractic Research Centre, RMIT University, Melbourne, Australia. METHODS: One hundred five patients with cervicogenic headache were randomized into 2 groups. After a baseline observation period, Group 2 received manipulation (toggle recoil) to the cervical spine, whereas Group 1 received sham manipulation. In the next trial phase, Group 1 received manipulation, whereas Group 2 received no treatment. This was followed by the final trial phase, in which Group 2 received sham manipulation and Group 1 received no treatment. After each trial phase, active range of cervical motion was measured with a strap-on head goniometer by 2 blinded examiners. RESULTS: After receiving spinal manipulation, active range of motion in the cervical spine increased significantly (P < .0006) in Group 2 compared with Group 1, and this difference between the treatment groups disappeared after the third trial phase in which Group 1 also received manipulation, as expected. CONCLUSION: Spinal manipulation of the cervical spine increases active range of motion. 相似文献
750.
Driscoll GL; Tyler JP; Knight DC; Cooke S; Kime L; Clark L; Bernstein J 《Human reproduction (Oxford, England)》1998,13(1):84-87
While there is much information and discussion on pregnancy failure after
assisted reproductive technologies, less emphasis is placed on the failure
to collect oocytes after apparently successful ovarian stimulation. This
retrospective survey reviewed 4973 treatment cycles in order to obtain
information about the likelihood of this event. Overall 42 women (43
treatment cycles) failed to have oocytes collected [0.86% of treatments
started and 0.92% of women given human chorionic gonadotrophin (HCG)].
However, in only six cases was this failure unexpected (0.1%) with no
obvious potential clinical reason (i.e. all six cases had: HCG
administered; more than two follicles >15 mm in diameter; oestradiol
values >2000 pmol/l; <38 years old; normal body mass index).
Indifference concerning uncommon events is fraught with peril, as although
rare, the particular outcome may be devastating to the individual, both
economically and psychologically. Eighteen of the 42 women did not return
for on-going treatment suggesting increased contact by clinic staff may be
required when oocyte retrieval is not achieved. These data suggest that the
failure to collect oocytes after apparently successful ovarian stimulation
is rare and random. The information has proved useful in allaying the fears
of couples contemplating assisted reproductive technologies.
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