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221.
The purpose of this study was to evaluate the relationship between postoperative abdominal incision problems and opening subcutaneous tissues with electrocautery or scalpel. Women scheduled for elective abdominal hysterectomy who gave informed consent were randomly assigned to subcutaneous abdominal wall tissue incision by electrocautery or scalpel. Postoperative abdominal wound problem diagnoses included seroma, hematoma, infection, or dehiscence without identifiable etiology. Fifteen of 380 women (3.9%) developed a wound problem; six had scalpel and nine had electrosurgical subcutaneous incisions (P = 0.4). Thicker subcutaneous tissues (P = 0.04) and concurrent pelvic infection (P < 0.001) were significant risk factors for postoperative wound problems. Only two women (0.5%) developed an infection. We conclude that the method of subcutaneous tissue incision was unrelated to the development of postoperative abdominal incision problems in 380 women undergoing elective abdominal hysterectomy.  相似文献   
222.
The sweat patch is a new, noninvasive method designed to estimate the ethanol consumption of drinking subjects. It consists of salt-impregnated absorbent pads protected by a plastic chamber with attached water-tight adhesive. The patch reportedly collects transepidermal fluid at a steady rate for up to 10 days. Recent laboratory research has indicated a linear relationship between the concentration of ethanol in transepidermal fluid and mean concentration of ethanol in blood. Levels of ethanol in the sweat patch allowed identification of persons drinking at least 0.5 g of ethanol/kg/day with 100% sensitivity and specificity. The study reported here was conducted to test the field effectiveness of this sweat patch in normal, active research subjects. First, several pretests were conducted to determine the optimal location of the patch on the body and its fluid uptake at various sites. A laboratory experiment using nonalcoholic subjects was conducted to replicate previous work, and methods of measuring ethanol concentration in the patch were refined. A field test of the patch was then carried out. Healthy active volunteers drank a single "moderate" dose of ethanol (0.5 g of ETOH/kg of body weight) and then remained abstinent for the next 3 days. A week later, a "heavy" dose (1.0/kg of body weight) was consumed. Only a trace of ethanol was detected in any of the patches worn in either experiment. The patch did not measure ethanol in the transepidermal fluid under field conditions. Thus, further design modifications and pilot testing are required before the full benefits of this unobtrusive measure of drinking can be realized.  相似文献   
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224.
Cardiac tamponade is an unusual cause of sudden death in the first weeks of life. We present two cases of cardiac tamponade in the neonatal period that caused death 5 to 6 days following the insertion of intracardiac lines, to draw attention to the possibility of a "delay phenomenon" between the time of the initial procedure and the occurrence of sudden and unexpected death. The presence of blood or clear fluid within the pericardial sac should prompt careful examination of the myocardium for small foci of traumatic damage, particularly when the fluid is under pressure or of large volume. Although the development of circulatory impairment or shock in the days following central line insertion or catheterization raises the possibility of tamponade, it should be noted that sudden death may occur in the absence of any significant antemortem symptoms or signs.  相似文献   
225.
The objective of this investigation was to correlate Xenon-133 inhalation rCBF measurements with the pattern of cortical arterial filling on intravenous DSA in 18 patients with unilateral internal carotid artery occlusion. Of 9 patients showing symmetrical filling of hemispheric cortical arteries, none showed an inter-hemispheric difference in rCBF ( delta Fg) greater than 10ml/100gm/min. Of 9 patients showing delayed cortical opacification ipsilateral to the internal artery occlusion, 3 showed a delta Fg greater than 10ml/100gm/min, 3 showed a delta Fg in the 7-10ml/100gm/min range, and 3 had a delta Fg less than 7ml/100gm/min. All patients with asymmetric abnormalities in the rCBF profile had the delayed pattern of cortical filling on DSA. The presence of symmetrical hemispheric opacification of cortical arteries on DSA indicates adequate interhemispheric redistribution of rCBF and patent inter-hemispheric collateral channels, but not necessarily normal cerebral blood flow. The presence of delayed cortical arterial opacification on the side of internal carotid artery occlusion does not necessarily imply significant inter-hemispheric rCBF differences, nor does it rule out a normal rCBF. The presence of bilateral reduction of rCBF and symmetrical cortical artery filling on DSA may represent an "interhemispheric steal".  相似文献   
226.
Parental knowledge of their students' backpack weight and contents was assessed by identifying 188 students who carried backpacks weighing at least 10% of their body weights through a survey of 745 students in three elementary schools. Most parents (96%) had never checked their child's backpack weight; 34% had never checked the backpack contents.  相似文献   
227.
Objective assessment of auditory thresholds in noise‐induced hearing loss using steady‐state evoked potentials The purpose of this study is to evaluate whether steady‐state evoked potential (SSEP) can be used for objective estimation of auditory thresholds in patients with noise‐induced hearing loss (NIHL). Eleven subjects (22 ears) with a characteristic audiometric notch between 3000 and 6000 Hz participated in this study. Both pure‐tone thresholds and SSEP thresholds were obtained for each ear of all subjects. The correlation of SSEP thresholds and pure‐tone thresholds was assessed. The results show that SSEP thresholds predicted pure‐tone thresholds with correlation coefficients (r) of 0.86, 0.92, 0.94 and 0.95 at 500, 1000, 2000 and 4000 Hz respectively. Typically, the SSEP thresholds overestimate the pure‐tone thresholds by 10–20 dB, but they closely reflect the configuration of the audiogram. The strength of the relationship between SSEP and pure‐tone thresholds increased with increasing frequency and increasing degree of hearing loss. In conclusion, SSEP can be used as a reliable and objective tool to assess auditory thresholds in patients with noise‐induced hearing loss with high‐frequency dips.  相似文献   
228.
Should patients with asymmetrical noise‐induced hearing loss be screened for vestibular schwannomas? The Peterborough ENT department receives many referrals for MoD personnel who have suffered hearing loss from occupational noise exposure. Those patients with asymmetrical sensorineural hearing loss are routinely screened for vestibular schwannomas by MRI scanning. Scan reports from the past 5 years have been reviewed and out of 152 scans, four revealed vestibular schwannomas giving a pick‐up rate of 2.5%, which compares favourably with other published pick‐up rates. Review of the audiograms in these cases suggests that they can be misleading in this context. The conclusion is that patients with noise‐induced asymmetrical hearing loss should be screened for acoustic neuromas.  相似文献   
229.
We retrospectively studied 43 adolescent boys treated with orthoses for idiopathic scoliosis to assess the usefulness of the timing of peak height velocity for predicting growth remaining and the likelihood of curve progression when compared with Risser sign, closure of the triradiate cartilage, and chronologic age. We compared the peak height velocity data in boys to our previous work for girls with adolescent idiopathic scoliosis. We found the median height velocity plots showed a similar high peak and sharp decline as is found in girls. All 13 patients with a curve magnitude > 30 degrees at the time of peak height velocity had progression of their scoliosis to > 45 degrees despite bracing. Four of 29 patients (14%) with curves < or = 30 degrees at peak height velocity progressed to 45 degrees. These values generate a sensitivity of 76%, specificity of 100% and accuracy of 91% in predicting progression to 45 degrees. Similar values have been found in female patients. The use of peak height velocity to predict the length of time for remaining growth was superior to Risser sign and chronologic age for boys with idiopathic scoliosis. Closure of the triradiate cartilage approximated the timing of peak height velocity in boys.  相似文献   
230.
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