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51.
PurposeCompletely displaced distal radius fractures in children have been traditionally reduced and immobilized with a cast or pin fixed. Cast immobilization leaving the fracture displaced in the bayonet position has been recently suggested as a non-invasive and effective treatment alternative. This is a pilot comparative study between reduction and no reduction.MethodsWe assessed subjective, functional and radiographic outcome after a minimum 2.5-year follow-up in 12 children under ten years of age who had sustained a completely displaced metaphyseal radius fracture, which had been immobilized leaving the fracture in an overriding position (shortening 3 mm to 9 mm). A total of 12 age-matched patients, whose similar fractures were reduced and pin fixed, were chosen for controls. ResultsAt follow-up none of the 24 patients had visible forearm deformity and the maximal angulation in radiographs was 5° Forearm and wrist movement was restored (< 10° of discrepancy) in all 24 patients. Grip strength ratio was normal in all but three surgically treated patients. All patients had returned to their previous activities. One operatively treated boy who was re-operated on reported of pain (visual analogue scale 2).ConclusionThe results of this study do not demonstrate the superiority of reduction and pin fixation over cast immobilization in the bayonet position of closed overriding distal metaphyseal radius fractures in children under ten years with normal neurovascular findings.Level of evidenceIII  相似文献   
52.
探讨DR颈椎斜位影像中应用组织均衡技术的优势   总被引:4,自引:0,他引:4  
目的探讨颈椎斜位直接数字化X线摄影(direct digital radiography,DR)中,采用组织均衡技术的DR图像与标准DR图像的差别。方法利用中国医科大学附属第一医院引进的GE—Revolution XQ/Ⅰ型DR机对所摄的颈椎斜位影像中随机抽取100例作为分析资料。应用组织均衡技术对图像进行处理,同时与标准DR图像进行比较。结果应用组织均衡技术的图像,同一幅图像上不同部位的细节均可清晰显示;标准DR图像需调节不同的窗宽、窗位才能清晰显示或不能显示不同体厚部位的细节。结论在直接数字化X线摄影中,应用组织均衡技术能明显改善因受体厚度影响而难于观察部分的可视性,同时又不牺牲其他部分的细节显示,使DR的应用更完美。  相似文献   
53.
目的:探讨国产吻、缝合器在超低位直肠前切除术中的应用。方法:对27例直肠癌患者行超低位直肠前切除,应用上海产金钟牌缝合器、吻合器,进行结肠-直肠吻合。结果:本组根治性切除25例(92.6%);1例发生吻合口瘘,发生率为3.7%;吻合口狭窄3例,发生率为11.1%,均经保守治疗治愈。结论:合理使用国产缝合器、吻合器可完成超低位直肠癌的保肛手术,可达保肛、根治、降低费用、减少并发症的目的。  相似文献   
54.
目的:探讨如何处理持续性枕后位,以尽可能减少母儿并发症。方法:总结分析了120例持续性枕后位的孕周、胎儿体重、产重长短对分娩方式的影响以及不同分娩方式对母儿的影响。结果:当孕周大于等于40周,胎儿体重大于等于3500g,潜伏期大于8h,活跃期大于4h时,剖宫产率明显增高,持续性枕后位所致的产程延长及手术助产增加了新生儿窒息率和产妇的并发症。结论:对持续性枕后位应正确观察处理各产程,早期诊断,充分估计其阴道分娩的可能性,对不适于阴道分娩者,应果断行剖宫产术,以降低母儿并发症。[  相似文献   
55.
SUMMARY  Previous studies have shown that premature infants may be at risk for hypoxemia and bradycardia when placed in standard car seats. However, the relationship of such breathing abnormalities to sleep state have not been studied. The purpose of the present study was to investigate the effect of car seat positioning on respiratory patterns in preterm infants during sleep and to evaluate their relationship to sleep state. Complete polysomnography, including sleep and breathing parameters, was performed on twenty-eight premature infants. Each infant was randomly assigned to the car seat or prone (crib) position for the first recording period. Following the recording of at least two sleep cycles, the position was reversed. The percentage of active and quiet sleep was calculated and breathing parameters were measured. In the car seat, the infants spent significantly more time in active sleep and less time in quiet sleep than in the prone position, of the respiratory parameters, periodic breathing (PB) was significantly higher in the car seat. The presence of at least one abnormal breathing events (bradycardia, desaturation, PB apnoea) was also significantly higher in the car seat. An analysis of variance (ANOVA) of PB revealed significant sleep-state effect (active vs. quiet sleep), but no significant condition or interaction effects, indicating that PB was more frequent in active sleep regardless of the sleeping condition. It is concluded that increased active sleep in the car seat condition, rather than the positioning of the infant in the seat per se, may account for the increase in periodic breathing and possibly other breathing abnormalities reported in car seats.  相似文献   
56.
The effects of a series of benzodiazepine (BZ) receptor ligands, ranging from a full agonist through to partial inverse agonists, were examined on short term working memory in the rat. The behavioural paradigm used was a discrete trial, operant delayed matching to position task, as originally described by Dunnett (1985), with delays of 0, 5, 15 and 30 s. The benzodiazepine receptor (BZR) full agonist lorazepam (0.25, 0.375 and 0.5 mg/kg) dose and delay dependently impaired matching accuracy. Lorazepam also increased the latency to respond and decreased the number of nose pokes made into the food tray during the delays. In contrast, the BZR partial agonist ZK 95 962 (1, 3, 10 mg/kg) did not affect matching accuracy, but did increase the speed of responding. The BZR antagonist ZK 93 426 (1.25, 5, 25 mg/kg) had no effects in this paradigm. The BZR weak partial inverse agonists Ro 15-4513 (0.1, 1 and 10 mg/kg) and ZK 90 886 (1, 3 and 10 mg/kg) did not affect accuracy of performance. However, both of these drugs increased the latency to respond and decreased nose poke responses. These motoric effects were particularly strong following 10 mg/kg Ro 15-4513. This shows that the effects of drugs on the accuracy of responding and on the speed of responding can be dissociated. The BZR partial inverse agonist FG 7142 had effects on matching accuracy that were dependent upon dose. The lowest dose of FG 7142 (1 mg/kg) significantly improved accuracy, whereas the highest dose (10 mg/kg) impaired accuracy. This impairment induced by FG 7142 (10 mg/kg) was accompanied by an increase in the latency to respond and a decrease in the number of nose pokes. Taken together, these results show that the accuracy of delayed matching performance can be modulated in opposite ways by the BZR full agonist lorazepam and a low dose of the BZR partial inverse agonist, FG 7142.  相似文献   
57.
颅骨翼区形态观测   总被引:1,自引:0,他引:1  
目的:积累解剖学资料,为临床诊断与治疗提供解剖学基础。方法:对翼区及其周围形态结构进行解剖学观测及统计学处理。结果:进行了翼区分型、翼区中点定位、翼区中点与脑膜中动脉沟前支关系、颧骨额突上角、下角及颧弓形态的观察。结论:翼区分型结果与文献记载相似,翼上骨各型比例与文献记载有异,翼区中定位以双水平距与垂直距共同定位较为简便而准确,翼区中点多位于脑膜中动脉沟前支前上方,颧骨额突上、下角及颧弓形态各不相同。  相似文献   
58.
Prostaglandin E1-induced hypotension (25% reduction from the preadministration level in mean arterial pressure) was applied to thirteen patients. Eight patients among them were operated in the supine position (group I) and other five in the prone position (group II). The maintenance dose of PGE1 was considerably lower in group II than in group I (0.067µg·kg–1·min–1 vs. 0.119µg·kg–1·min–1). In group I, there was a significant increase in CI, with a significant decrease in SVRI and PVRI during PGE1-induced hypotension. Such a high dose of PGE1 (0.119µg·kg–1·min–1) was considered to have a direct dilating action on the systemic resistance bed as well as on the pulmonary vasculature. It was considered that the suppression of hypoxic pulmonary vasoconstriction could be a mechanism to increase venous admixture during PGE1-induced hypotension. In group II, there was no significant increase in CI, and no significant decrease in SVRI and PVRI. PGE1-induced hypotension can be safely applied to the anesthetized patients, but we should be careful to apply it to the patients in the prone position, because lower dose of PGE1 can induce severe hypotension, which is not accompanied by the increase in CI as occures in the patients in the supine position.(Hirose M, Yoda K, Sakai K, et al.: Comparative Study on the cardio-respiratory change during prostaglandin E1-induced hypotention in the patients in the supine and prone position. J Anesth 5: 30–35, 1991)  相似文献   
59.
This Capsular Lens (ONG, type IV, to be called O.C.L.) has been developed for routinely performed extracapsular cataract extraction with lens implantation. The fundamental surgical procedure was based on continuing experience with the bimanual aspiration-irrigation technique and system developed by the author in 1971. The biomechanical properties of the asymmetric partly flexible, haptic loops are designed to give tensionfree fixation in two capsular pockets. The plano-anterior position of the lens ensures well-defined irido-lenticular clearance and proper alignment of the convex side with the posterior capsule. Consequently no iridectomy or iridotomy is needed for proper aqueous flow.  相似文献   
60.
Summary In 6 night nurses the daily course of body temperature and pulse rate was measured under strict resting conditions immediately after a 7 to 18-day period with night work as well as after a 10-day period of recovery under normal life conditions. Three of the subjects were morning types and three evening types according to the Horne-Östberg-Questionnaire as well as to the phase position of the body temperature cycle.In order to quantify the changes in amplitude, phase position, and frequency a flattening index, a circadian deformation index, and according to the calculated phase shift a corrected deformation index were used. While the evening types reacted with a flattening of their circadian amplitude and thus gained a greater tolerance, the morning types hyper reacted when exposed to the inverse life pattern, developing an increased amplitude and adding to the circadian deformation by ultradian periods. No significant differences could be detected in phase shift. Higher amounts of subjective complaints and deficit of sleep as well as differences in the additionally controlled vigilance functions demonstrated the lower tolerance of the morning types to night work.The discussion concerns the methological basis of a quantitative evaluation of disturbance of the circadian system, and shows off, that the greater tolerance of evening types to night work is based on a lower reagibility of the vegetative functions to changes in the outer environment.  相似文献   
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