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91.
The best anastomotic agent to join nerve ends is controversial. This paper describes a controlled trial between a collagen tube wrap and a tissue glue to anastomose the rat facial nerve. There was no difference in the results using photographic, histological and electrophysiological techniques.  相似文献   
92.
将大鼠的腓总神经切断后,进行如下4组实验:A.原位3mm间隙动脉套桥接,B.原位断端外膜缝合,C远侧断端旋转180°3mm间隙动脉套桥接,D远侧端旋转180°外膜缝合。术后12周的电生理学,组织学评价显示,B组神经再生效果最佳,A、C两组接近B组,而D组较差。  相似文献   
93.
目的:了解肾上腺素对丁哌卡因肌间沟臂丛神经阻滞的药效学及药动学影响。方法:选择ASA Ⅰ~Ⅱ级肩部或上肢择期手术患者16例,随机分成两组,试验组与对照组各8例,分别用含或不含肾上腺素的0.75%丁哌卡因2mg/kg行肌间沟臂丛阻滞。对比观察两组的临床效果及药代动力学。结果:与对照组比较,试验组阻滞完善时间及镇痛时间延长(P<0.05或0.01)。试验组与对照组Cmax分别为0.8295±0.2893ug/ml和0.8898±0.2572ug/ml,Tmax分别为37.6018±8.3461分钟和29.3156±11.1991分钟(P>0.05)。药代动力学参数t1/2Ka及K_(21)两组间有显著性差异(P<0.05或0.01)。结论:肾上腺素能延长丁哌卡因的阻滞完善时间、镇痛维持时间及吸收半衰期,但对血药浓度无明显影响。  相似文献   
94.
目的:研究面神经撞击伤后面神经核内生长相关蛋白(GAP-43)的变化及高压氧(HBO)治疗的影响。方法:利用BIM-Ⅱ型生物撞击机致家兔右侧面神经干损伤,应用SP免疫组化染色法观察损伤后1、3、7、14和21天(分别用HBO治疗及不用HBO为对照)面神经核内GAP-43的变化,并用电镜观察面神经干超微结构变化。结果:面神经损伤第1天,伤侧面神经核区GAP-43样免疫反应性神经元(GLIN)开始增多,第14天其增多达到高峰,第21天逐渐下降。HBO治疗组伤后不同时期GLIN的增多明显高于对照组。伤后第21天,与对照组相比HBO组面神经干电镜观察可见较多的新生髓鞘。结论:HBO治疗可使伤后面神经核内GLIN增多,因而有助于面神经损伤后的修复与再生。  相似文献   
95.
周围性面神经损伤患者对侧神经支配的研究   总被引:6,自引:0,他引:6  
目的 通过测定面神经损伤患者组及大学生志愿者组面神经各分支对侧神经支配率 ,探讨周围性面肌瘫痪恢复过程中面神经对侧代偿支配的问题。方法 分别测定大学生志愿者 2 2例( 2 2侧 )及 10 8例面神经损伤患者的面神经电图对其对侧神经支配率进行分析其中损伤组又按发病原因不同 ,分为医源性损伤组、Bell氏面瘫组和创伤性损伤组 ,测试损伤支数为Ⅰ支 76支 ,Ⅱ支 81支 ,Ⅲ支 88支 ,Ⅳ支 6 6支。结果 ①损伤组 3组间对侧支配率差异无显著性 (P >0 0 5 ) ;②损伤组Ⅰ、Ⅱ支对侧支配率明显高于志愿者组 (P <0 0 0 1) ;③损伤组Ⅰ支对侧支配率明显高于Ⅱ支(P <0 0 0 1)。结论 面神经损伤后 ,存在对侧神经支配功能增强的表现  相似文献   
96.
97.
Changes in calcitonin gene-related peptide-like immunoreactivity (CGRP-LI) at the motor endplates of botulinum toxin-paralysed rat muscles were investigated using immunohistochemistry. One day following toxin injection, a dramatic increase in CGRP-LI was detected at the motor endplates and within preterminal axons of the soleus and gastrocnemius muscles. The upregulation of CGRP-LI persisted throughout the period during which muscle fibres were paralysed and new neuromuscular junctions were being formed by the growing sprouts. Decline of CGRP-LI at the motor endplates coincided with clinical recovery. Both up- and down-regulation of CGRP-LI took place earlier in the soleus than in the gastrocnemius muscle. Up-regulation of CGRP-LI was also detected in a subpopulation of motor axons in the sciatic nerves and in the spinal motor neurons innervating the paralysed muscles. These results indicate that levels of CGRP are regulated, at least partly, by changes in the target innervation. They also suggest an important role for CGRP in the regenerative processes following muscle paralysis.  相似文献   
98.
目的:介绍带血管蒂前臂后皮神经电缆式移植修复上臂桡神经缺损的应用解剖、手术方法及临床效果。方法:在20侧成人上肢标本上,观测前臂后皮神经及桡侧副动脉的行程及外径,设计以桡侧副动脉为蒂的前臂后皮神经电缆式移植修复上臂桡神经缺损的新术式并应用于临床。结果:前臂后皮神经与桡侧副动脉伴行关系密切,具有形成带血管蒂前臂后皮神经转移的解剖学条件;前臂后皮神经横径2.0cm左右,可切取长度15.0cm左右,折叠后可以修复7.0cm左右的桡神经缺损。同时,术中发现神经供体断端出血活跃,说明带血供的前臂后皮神经移植的血供是可靠的。临床应用8例,神经缺损3.5~6.0cm,随访10个月~3年,效果满意。按陆裕朴介绍的评定标准:优4例,良3例,可1例。结论:该术式转移灵活,操作简单、安全、可靠,对供区影响小,是修复上臂桡神经缺损的一种有用的方法。  相似文献   
99.
Objective: Mental nerve block is frequently used to aid repair of facial lacerations; both percutaneous and intraoral approaches to blocking this nerve are used, but have never been compared. The authors compared the two techniques for pain of administration and effectiveness of anesthesia. Methods: A prospective, randomized, single-blind, crossover study was conducted using ten healthy volunteers aged 22 to 33 years. Patients having prior experience with mental nerve blocks, lidocaine allergy, active oral/facial infection, or previous facial fractures were excluded. Bilateral mental nerve blocks were done using intraoral technique on one side and percutaneous technique on the other. Both techniques were used by the same investigator and were carried out with 27-gauge needles and 2.5 mL of 2% buffered lidocaine at room temperature injected over 20 seconds. The oral mucosa was topically anesthetized with viscous lidocaine for 1 minute prior to intraoral injection. The orders of the blocks and sides of the face anesthetized were randomized. Subjective and objective pain (visual-analog scale), efficacy (anesthesia of lower lip), time to onset, and duration of anesthesia were evaluated. Results: The intraoral technique was subjectively less painful than the percutaneous approach in nine of ten subjects (p = 0.02). Scores on the visual-analog pain scale were significantly lower for the intraoral technique (p = 0.03). Intraoral injection produced lower-lip anesthesia in 10/10 subjects versus 7/10 for percutaneous (p = 0.25). Times to onset (approximately 1–2 minutes) and durations of anesthesia (approximately one hour) were similar for the two techniques. Conclusion: The intraoral approach to the mental nerve block with adjunctive topical anesthesia was subjectively and objectively less painful than the percutaneous approach without adjunctive anesthesia. While the intraoral approach had a greater efficacy of lower-lip anesthesia and a longer duration of action, these differences were not statistically significant.  相似文献   
100.
Virtually all cell types in the inner ear develop from the cells of the otic vesicle. The otic vesicle is formed by the invagination of non-neural ectodermal cells known as the otic placode. We investigated whether a recently described cell population, originating from the ventral part of the hindbrain neural tube known as the ventrally emigrating neural tube (VENT) cells, also contributes cells to the otic vesicle. The ventral hindbrain neural tube cells were labeled with the fluorescent vital dye DiI or replication-deficient retroviruses containing the LacZ gene in chick embryos on embryonic day 2, after the emigration of neural crest from this region. One day later, the labeled cells were detected only in the hindbrain neural tube. Shortly thereafter, the labeled cells began to appear in the eighth (vestibulocochlear) cranial nerve and otic vesicle. From embryonic day 3.5-5, the labeled cells were detected in the major derivatives of the otic vesicle, i.e. the endolymphatic duct, semicircular canals, utricle, saccule, cochlea, and vestibulocochlear ganglion. That the emigrated cells originated from the ventral part of the hindbrain neural tube was confirmed by focal application of DiI impregnated filter paper and with quail chimeras. It is concluded that, in addition to the otic placode cells, the otic vesicle also contains the ventrally emigrating neural tube cells, and that both cell populations contribute to the structures and cell types in the inner ear. It is well known that inductive signals from the hindbrain are required for the morphogenesis of the inner ear. The migration of the hindbrain neural tube cells into the otic vesicle raises the possibility that the inductive effect of the hindbrain might be mediated, at least in part, by the ventrally emigrating neural tube cells and that, therefore, a mechanism exists that involves cells rather than diffusible molecules only.  相似文献   
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