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41.
Background: The Bullard laryngoscope is useful for the management of a variety of airway management scenarios. Without the aid of a video system, teaching laryngoscopy skills occurs with indirect feedback to the instructor. The purpose of this study was to determine if use of a video system would quicken the process of learning the Bullard laryngoscope or improve the performance (speed or success) of its use.

Methods: Thirty-six anesthesia providers with no previous Bullard laryngoscope experience were randomly divided into two groups: initial training (first 15 intubations) with looking directly through the eyepiece (n = 20), or with the display of the scope on a video monitor (n = 16). The subjects each then performed 15 Bullard intubations by looking directly through the eyepiece.

Results: There was not an overall significant difference in laryngoscopy or intubation times between the groups. When only the first 15 intubations were considered, the laryngoscopy time was shorter in the video group (26 +/- 24) than in the nonvideo group (32 +/- 34;P < 0.04). In the first 15 patients, there were fewer single attempts at intubation (67.9%vs. 80.3%;P < 0.002) and more failed intubations (17.2%vs. 6.0%;P < 0.0001) in the nonvideo group.  相似文献   

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The glycosaminoglycan layer of bladder has been proposed to play a crucial role in protecting the bladder from harmful substances in urine. Rats were partially cystectomized to determine whether bladder glycosaminoglycans are routinely eluted from the bladder surface in detectable quantities. Cystectomy produced no detectable qualitative or quantitative changes in excreted GAG thereby showing that most urinary glycosaminoglycan originates in the kidney and not from the bladder. Damaging the glycosaminoglycan layer by a dilute acid wash, however, leads to a consistent decrease in the output of urinary GAG which recovers to normal at the same rate as the layer regenerates. This suggests that the newly exposed sites tightly bind urinary GAG. We suggest that such binding may be a component of the normal physiological defense mechanism of the bladder. The bladder glycosaminoglycan layer was isolated, dilute acid being used to elute ionically-bound material and brief trypsinization to elute intercalated proteoglycans from the luminal surface. The GAG from the luminal surface, which was present at a density of one chain per 50 nm.2 of bladder surface, was quite different in composition from that isolated from the whole bladder.  相似文献   
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Deaths of heroin users in a general practice population   总被引:4,自引:1,他引:3       下载免费PDF全文
Recent evidence suggests that heroin users in the UK are 16 times more likely to die than otherwise expected, although causes of death are varied. The present investigation examines deaths of heroin users at a large Scottish general practice over a four-year period prior to 1 July 1985. A mortality rate of 9.72 per 1000 heroin-user patients per year was observed, roughly half that previously reported, although this difference did not prove to be statistically significant. A higher proportion of the observed deaths were attributed to heroin, and fewer to the misuse of other drugs, and it is speculated that this may reflect the practice's policy of not prescribing opiates to heroin users. Factors associated with heroin-user deaths are examined and areas identified where general practitioners may help to avert some of these deaths.  相似文献   
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The treatment of keloid and hypertrophic scars remains difficult. Enzymatic digestion of keloid scars has been previously proposed as an effective treatment strategy for reducing the volume of keloid scars. To test this, we administered intra-lesional injections of pure collagenase (between 600 and 4500 units for each scar) into the keloid and hypertrophic scars of seven human volunteers (five keloid and two hypertrophic scars). Five patients (three keloid and two hypertrophic) received more than one injection of collagenase. The treatment resulted in a temporary reduction in scar volume for three of the patients with keloid scars. However, scar volumes for these three patients returned to the same (or greater) levels after 6 months of follow-up. Treatment with collagenase produced no change in scar volume for the two patients with hypertrophic scar. Side effects were numerous and severe including; pain, swelling, blistering, ulceration and ecchymosis at the site of injection. One patient required admission to hospital for 48 h after the first injection. Maximum length of follow-up was 6 months. None of the seven patients completed the study and returned for final follow-up at 2 years. This pilot study suggests that treatment of keloid and hypertrophic scars with intra-lesional injections of collagenase is ineffective.  相似文献   
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The success rates of living-related donor (LRD) transplants are clearly superior to those obtained with cadaver donors. However, caution should be exercised when considering LRD transplantation for a condition which has an increased chance of recurring after transplantation and causing ultimate graft failure. The recurrence rate of focal segmental glomerulosclerosis (FSGS) in the allograft is 20%–40%, with graft failure resulting in 40%–50% of these cases. However, these figures may be an underestimation of the true rate of recurrence of FSGS. Once a first transplant fails due to recurrent disease, the risk of recurrence in the second transplant approaches 80%. Subgroups of patients at high risk for recurrence have been identified. In patients not at high risk for recurrent FSGS, the use of a LRD should be considered, provided that the donor and recipient and their families have been informed that the disease may recur and lead to graft failure. In patients at high risk for recurrence, a LRD transplant should be avoided. Hopefully, future development of a simple and reliable test to predict the likelihood of recurrence will enable us to counsel and advise our patients with FSGS about the wisdom or dangers of proceeding with a LRD transplant.  相似文献   
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