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41.
42.
Single trial amplitude, latency jitter, and electroencephalographic (EEG) power were examined as sources of the group difference in averaged P300 amplitude among 15 traumatically brain injured and 20 control individuals in an auditory oddball paradigm. Mean amplitude of the individual trials was highly correlated with the amplitude of the averaged P300, with little additional unique variance attributable to latency jitter or EEG power. The group difference in P300 amplitude was also explained by the mean amplitude of the single trials. These results support the robustness of the event-related potential averaging technique within the paradigm used.  相似文献   
43.
神经移位修复臂丛神经根性撕脱伤   总被引:3,自引:2,他引:1  
1987年7月~1994年6月,对21例臂丛神经根性撕脱伤采用神经移位修复。其中复合移位4组神经(膈神经、副神经、颈丛运动支、肋间神经)者1例,3组(膈神经、副神经、颈丛运动支)者6例,2组(膈神经、副神经)者9例,1组(膈神经或颈丛运动支或肋间神经)者5例。术中发现臂丛神经变异1例,对4例合并锁骨下动脉损伤者,在神经移位的同时进行血管修复,促进患肢的血液循环,有利于神经的康复。随访到19例,随访时间为8个月~6年2个月,优良率达73.7%。认为,神经移位术是修复神经根性撕裂伤的常规方法,合并血管损伤者也应同时修复,对促进神经功能恢复有利  相似文献   
44.
总结胸腹轴型皮瓣早期修复上肢不同部位的深度蛇伤溃疡的经验,评价其应用价值。本组16例,胸脐皮瓣2例,侧胸腹皮瓣1例,髂腰皮瓣5例,下腹皮瓣6例,下腹分叶皮瓣1例,髂腰加下腹Y形皮瓣1例。术后1例皮瓣远端坏死,3例轻度感染,16例断蒂后全部成活。随访3个月~7年,皮瓣质地和弹性均好,手功能基本恢复。认为,带蒂胸腹轴型皮瓣是修复上肢深度蛇伤溃疡理想的方法。  相似文献   
45.
We present a case in which an open fracture of the ulna penetrated the skull and caused a comminuted, depressed skull fracture with a large intraparenchymal hematoma containing bone fragments.  相似文献   
46.
目的 探索手指屈肌腱在近节指骨段不同范围损伤时对屈指肌腱功能的影响。方法 采用12只成人尸体手指。实验分为:第一阶段屈指肌腱完整,以后四个阶段依次沿近节指骨掌侧小线闭开小央1/4、1/2、3/4及全长。在掌指关节被动屈80°和掌指关节屈80°同时近侧指关节屈100°时,测量指浅屈肌腱(FDS)和指深屈肌腱(FDP)的滑动距离。根据肌腱力臂和滑动距离的关系,得出屈指肌腱在掌指关节处和近侧指间关节及肌腱在近节指骨段的弓弦畸形程度。结果 腱鞘中央1/4切开时,指屈肌腱的滑动距离、力臂均无显著变化;1/2切开后,单纯屈曲掌指关节时的FDS腱和掌指、近节指间关节屈曲时的FDS、HDP腱的滑动距离和力臂较腱鞘完整时显苫增大(P<0.05);切开3/4长度后,FDS、FDP腱滑动距离均有统计学意义变化,FDS、FDP腱力臂平均增加8~9%;全切开腱鞘,FDS、FDP腱滑动距离变化正统计学上有高度显著性(P<0.01),两腱力臂分别增加16%和15%。随腱鞘切开范围增大,FDS、FDP在近节指骨段的弓弦畸形程度也越来越大。结论 从肌腱的生物力学变化可见,近节指骨段腱鞘的小范围损伤如中间1/4以内损伤时,对肌腱功能影响小,可以不予修复;若损伤超过1/2长度,尤其对腱鞘全长损伤,应予以修复以恢复肌腱功能。  相似文献   
47.
1. The authors investigated the effect of two extrahepatic cholestasis models (one by bile duct ligation and the other by choledocho-jugular fistula) on the hepatic clearance of horseradish peroxidase in male Sprague-Dawley rats divided into four groups. 2. In groups A (n = 5 rats) and B (n = 5), bile duct ligation was performed, while a choledocho-jugular fistula was created in groups C (n = 5) and D (n= 7). A 10 mg intravenous bolus of horseradish peroxidase was injected after 24 h (groups A and C), 48 h (groups B and D) or 1 h (Group E; five sham-operated rats). Serum and bile samples were then serially collected for 2 h. 3. In all groups, serum horseradish peroxidase levels increased soon after injection and then rapidly decreased, the curves being similar. Biliary excretion increased for 30 min and then slowly decreased. The highest horseradish peroxidase biliary concentrations and outputs were found in Group B followed by Group A; both groups had significantly higher levels than Group E. No difference was found between horseradish peroxidase biliary excretion of groups C and D and that of sham-operated rats. 4. When each group was considered separately, sampling times correlated with the corresponding ratios of bile/ plasma HRP. Significant differences were found between the relative slopes of groups A, B and E, but not between those of groups C, D and E. 5. In conclusion, bile duct obstruction greatly affects the plasma-bile transfer of fluid phase markers, such as horseradish peroxidase, while single retention, caused by choledocho-jugular fistula, has no influence. The increased biliary hyperpressure related to the duration of cholestasis may account for the degree of horseradish peroxidase transfer which, in turn, probably depends on an enhanced paracellular passage.  相似文献   
48.
Paediatric dacryocystorhinostomy   总被引:1,自引:0,他引:1  
Of 258 cases of dacryocystorhinostomy performed on children in the period September 1981 to September 1991, 130 were for simple, unresolved congenital nasolacrimal duct obstruction. Other indications for surgery included punctal agenesis, lacrimal fistula, post-traumatic and post-inflammatory canalicular obstruction. Of 177 children without canalicular pathology, 171 (96%) were relieved of symptoms with one operation, without canalicular intubation. Of 81 cases with canalicular disease, 55 of 70 (79%) who underwent DCR plus canalicular intubation, and 10 of 11 who underwent DCR plus Lester-Jones tube, were substantially improved with one operation. No child required peroperative or postoperative blood transfusion. Dacryocystorhinostomy in childhood, in experienced surgical hands, is a safe procedure, achieving relief of symptoms in most cases, particularly in the absence of canalicular disease.  相似文献   
49.
A retrospective review was done of 69 children and adolescents (7-17 years old) who underwent 75 arthroscopies of the knee during a 5-year period. Girls were overrepresented (71%). Thirty-eight were children under the age of 16. Of 46 injuries, 34 (74%) happened during sports. Children and adolescents were divided into two age groups based on their presumed state of skeletal maturity (boys 9–15 and girls 7–14 in group I and boys 16–17 and girls 15–17 in group II); meniscal lesions were equally common in the two groups, whereas anterior cruciate ligament tears were more common in older children (NS). Eleven of 17 (65%) anterior cruciate ligament lesions were combined with other intra-articular pathology, most often meniscal tears (9/11). As in other studies, half of the prearthroscopic diagnoses were incorrect. A high frequency of incorrect prearthroscopic diagnoses and of combined lesions justifies arthroscopy as an important diagnostic tool in children and adolescents with a history of twisting knee injury or chronic nonspecific knee problems. Girls practising ball games seem to be especially prone to knee injuries leading to arthroscopy.  相似文献   
50.
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