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OBJECTIVE: To compare the effectiveness of three new topical anesthetics that do not contain cocaine (prilocaine-phenylephrine, tetracaine-phenylephrine [tetraphen], and tetracaine-lidocaine-phenylephrine) to that of tetracaine-adrenaline-cocaine (TAC) during laceration repair in children. DESIGN: Prospective, randomized, double-blind clinical trial. SETTING: The emergency department of an urban children's hospital. PARTICIPANTS: Children 1 year of age or older with a laceration /= 5 years of age using a visual analogue scale (VAS). Suture technicians, research assistants, and parents also scored pain using a seven-point Likert scale. In addition, suture technicians completed an anesthetic effectiveness scale. RESULTS: There was consistently no difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. A statistically significant difference was seen among anesthetics when comparing VAS and Likert scale scores of suture technicians and Likert scale scores of research assistants. Based on post hoc analyses, these statistically significant differences were between TAC and prilocaine-phenylephrine (suture technician VAS and Likert scale) and between TAC and tetracaine-lidocaine-phenyl-ephrine (suture technician Likert scale), but not between TAC and tetraphen. When power analyses were performed using alpha = 0.05 and beta = 0.20, it was possible to detect a difference of 1.2 VAS units for each of the observer groups. Based on anesthetic effectiveness scale scores, the three new topical preparations collectively performed significantly better on the face and scalp than on the extremities (relative risk = 1.83; 95% confidence interval 1.20 < relative risk < 2.79). CONCLUSION: This study demonstrated the effectiveness and safety of three new non-cocaine-containing topical anesthetics. Consistently, there was no statistical difference demonstrated between the effectiveness of tetraphen and that of TAC for each outcome measure of each observer group. Tetraphen offers an effective alternative to TAC during laceration repair in children.  相似文献   
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Increased placental apoptosis in intrauterine growth restriction   总被引:2,自引:0,他引:2  
OBJECTIVES: Our purpose was to investigate a possible role for apoptosis in the pathophysiologic mechanisms of intrauterine growth restriction. STUDY DESIGN: Placental samples were obtained from 43 uncomplicated third-trimester pregnancies and from 26 pregnancies complicated by intrauterine growth restriction. The definition used to identify cases of intrauterine growth restriction depended on three criteria: clinical evidence of suboptimal growth, ultrasonographic evidence of deviation from an appropriate growth percentile, and individualized birth weight ratios <10th percentile. Light microscopy was used to quantify the incidence of apoptosis. Electron microscopy and TUNEL (terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick end labeling) staining were used to confirm the occurrence of apoptosis. RESULTS: Quantification of apoptosis (medians and interquartile ranges) resulted in the following values: normal third trimester (n = 43) 0.14% of cells (0.08% to 0.20%) and intrauterine growth restriction third trimester (n  = 26) 0.24% of cells (0.16% to 0.29%). The incidence of apoptosis was significantly higher in placentas from pregnancies with intrauterine growth restriction compared with normal third-trimester placentas (p < 0.01, Mann Whitney U test). CONCLUSIONS: These results suggest that apoptosis may play a role in the pathophysiologic mechanisms of intrauterine growth restriction.(Am J Obstet Gynecol 1997;177:401)  相似文献   
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BACKGROUND: Implant systems that realign and stabilize a deformed spine continue to evolve. The purpose of the study of this case series was to determine the safety and effectiveness of a system designed to integrate hook, wire, screw, and post anchors for the treatment of a wide spectrum of neuromuscular disorders associated with pelvic deformity or the potential for deformity. METHODS: Forty-seven consecutive patients who had a spinal deformity that was due to cerebral palsy or an upper motor-neuron cerebral palsy-like disease (thirty-one patients), myelomeningocele (nine), Duchenne muscular dystrophy (four), or other disorders (three) were managed with Isola-Galveston instrumentation and arthrodesis. The average age at the time of the operation was fourteen years and three months (range, five years and four months to twenty-three years and nine months). Eight patients (17 percent) had an additional anterior discectomy and arthrodesis without instrumentation, and three (6 percent) had an additional decancellation egg-shell osteotomy. The forty-seven patients were followed for an average of forty-seven months (range, twenty-four to 100 months). The complications were tabulated to assess the safety of the procedure, and the correction of each deformity was calculated to determine the efficacy. RESULTS: There were no deaths, acute wound infections, or serious neurological problems. Reoperation was necessary in five patients (11 percent). One reoperation was performed because of a delayed deep wound infection; one, because of delayed sterile drainage; and one, for a pseudarthrosis repair. The remaining two reoperations were done for removal of an implant because the cephalad portion had become prominent. In addition to the pseudarthrosis that required a reoperation, there were three possible pseudarthroses that did not require a reoperation (overall prevalence of pseudarthrosis, 9 percent). Postoperative bracing was used for eleven patients (23 percent); it did not influence the rate of pseudarthrosis or possible pseudarthrosis. The average preoperative scoliosis of 70 degrees was corrected to 24 degrees (a 66 percent correction) at the time of the latest follow-up, and the average preoperative pelvic obliquity of 27 degrees was corrected to 5 degrees (an 81 percent correction). A survey of the patients, parents, and caregivers indicated that 96 percent of them were satisfied or very satisfied with the result of the operation. CONCLUSIONS: Isola-Galveston instrumentation seems as safe and effective as other types of instrumentation that have been studied in comparable series in the literature. Isola-Galveston instrumentation is probably more effective for the correction of pelvic obliquity and the maintenance of correction. Only a posterior procedure is used, and the instrumentation appears to decrease the need for an additional anterior approach. Spinal hook, wire, screw, and post anchors have been successfully integrated into one posterior spinal implant system.  相似文献   
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Mamillary and spinous process base wiring did not improve L5-L6 posterolateral fusion rate, stiffness, or strength in a previously established rabbit model. Specimen radiography significantly underestimated fusion rate when compared with manual palpation (37% versus 68%). Fused specimens were significantly stiffer (67.2 N/mm versus 41.1 N/mm) and stronger (177 N versus 121 N) in tension than were nonfused specimens. Deep wound infection, detected only at the time of sacrifice, apparently was more common with internal fixation (43% versus 21%). Noninfected specimens were significantly stiffer (63.3 N/mm versus 43.0 N/mm) and stronger (176 N versus 107 N) than were infected specimens.  相似文献   
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食品中明矾含量的快速测定方法   总被引:1,自引:0,他引:1  
梁伟  戴京晶  刘奋  林奕芝  莫浩联 《职业与健康》2006,22(14):1068-1069
目的建立一种能简单快速检测食品中明矾含量的方法。方法采用特征离子鉴别方法定性,用Na2EDTA络合滴定方法定量。结果该方法回收率在99.0%~102.8%之间,RSD在0.91%~1.38%之间。结论方法操作简单,准确性好,适合于大批量样本检测。  相似文献   
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