嗅神经鞘细胞移植联合应用GDNF促进大鼠脊髓损伤后功能恢复

目的 嗅神经鞘细胞（OECs）移植联合应用胶质源性神经营养因子（GDNF）恢复大鼠脊髓损伤的功能。方法 将成年大鼠分为脊髓半切洞损伤组（A组），脊髓半切洞损伤＋嗅神经鞘细胞移植组（B）和脊髓半切洞＋嗅神经鞘细胞移植＋胶质源性神经营养因子（C组）。手术后应用联合行为评分（CBS），感觉诱发电位（SEP）和运动诱发电位（MEP）检查，测定脊髓功能恢复情况。结果 3组CBS得分A组＞B组＞C组，SEP和MEP潜峰时，均A组＞B组＞C组，统计分析均差异显著性（P＜0．05）。结论 移植嗅神经鞘细胞＋胶质源性神经营养因子能促进损伤脊髓功能的恢复。     

脐带脱垂26例临床分析

目的　 探讨脐带脱垂与高危因素的关系 ,提高围产儿存活率。方法　 回顾性分析 2 6例脐带脱垂与胎位异常、分娩方式以及围产儿的预后等方面的关系。结果　 脐带脱垂发生率为 0 .2 9% ,头先露、臀先露和肩先露脐带脱垂的发生率分别为 0 .0 7%、3.2 7%和 13.6 4% ,3者比较 ,有显著性差异 (P <0 .0 1) ;脐带脱垂合并 2种以上并发症者 9例 ;以剖宫产围产儿存活率最高 ;脐带脱垂的围产儿死亡率为 19.2 3%。结论　 脐带脱垂与胎位异常有关 ,围产儿的死亡率与分娩方式及脐带受压的程度和脱垂的时间长短密切相关。早期诊断脐带脱垂 ,及时娩出胎儿 ,是提高围产儿存活率的关键     

支撑喉镜手术治疗声带息肉小结

目的:观察支撑喉镜下手术治疗声带息肉/小结的疗效.方法:对100例声带息肉/小结的患者在全麻下行支撑喉镜手术.结果:100例中,术后3d发音恢复正常31例,术后6d发音恢复正常34例,好转35例,随访3mo无复发.结论:支撑喉镜下手术治疗声带息肉/小结疗效好、创伤小、精确度较高,但同时要注意并发症的预防和处理.     

Dynamic gadolinium-enhanced MRI in the detection of spinal arteriovenous malformations

Arteriovenous fistulae and malformations (AVFs and AVMs) of the spinal cord are rare, potentially treatable causes of progressive disability. Although a variety of MRI abnormalities has been described, the diagnosis rests on the findings on selective spinal angiography.Collecting T2^*-weighted MR images during the passage of a gadolinium bolus gives information about perfusion and blood volume. We carried out dynamic MRI in seven patients with vascular abnormalities (5 dural AVFs, 1 intramedullary AVM, 1 cryptic angioma) and in two patients without an AVM. High resolution T1- and T2-weighted sagittal images of the whole spinal cord were first obtained using a multiarray receiver coil. Sagittal radiofrequency spoilt gradient echo images (GE34/25, flip angle 10⁰) were then obtained during bolus injection of gadolinium-DTPA. Abnormalities were seen in all seven patients with AVFs or AVMs. In the patient with an intramedullary AVM and four of the five with dural AVFs transient signal reduction was seen within the perimedullary venous plexus during passage of the bolus. The findings correlated well with those from selective spinal angiography. We conclude that dynamic MRI offers a useful adjunct to angiography and may localise an arteriovenous shunt when conventional MRI fails to do so. In combination with high-resolution imaging of the entire spinal cord the technique may make myelography redundant; it is simple, well tolerated and can be carried out without significant time penalty.     

Use of gadolinium chelates in MR imaging of the spine

Spinal disease can be divided into intramedullary, extramedullary-intradural, and extradural compartments. In the cord (intramedullary compartment), gadolinium chelates are useful to diagnose primary and metastatic tumors, inflammation, and demyelination, and to evaluate syringomyelia when a Chiari I malformation is not present. In the extra-medulullary-intradural compartment, gadolinium chelates are useful for the diagnosis of drop metastases, meningiomas, and schwannomas. In the extradural compartment, gadolinium chelates are most useful to distinguish recurrent disc herniation from epidural fibrosis in the postoperative back and may be useful to diagnosis the soft tissue component of osseous metastases.     

Convergence of occipital nerve and superior sagittal sinus input in the cervical spinal cord of the cat

Co-existence of facial and occipital pain may occur in occipital neuralgia, migraine and cluster headache; suggesting convergence of trigeminal and cervical afferents. Such convergence has been shown in humans and other animals, but the site and extent of this are uncertain. In anaesthetized adult cats, the superior sagittal sinus and occipital nerve were stimulated electrically, and extracellular recordings made in the dorsolateral area of the upper cervical cord using glass-coated tungsten electrodes. Of 49 units in 10 cats, 33 (67%) had input from the superior sagittal sinus and the occipital nerve. Thirteen (27%) had superior sagittal sinus input and 3 (6%) had occipital nerve input. Convergent receptive fields were identified mechanically in 7 units. These experiments in cats show convergent input from occipital nerve and superior sagittal sinus on dorsolateral area units in two-thirds of cases studied. This experimental site of trigeminocervical convergence may relate to referral of pain in occipital neuralgia and other headaches.     

体感诱发电位在椎管内占位显微手术中的监测

目的　评价体感诱发电位 (SEP)在神经外科脊髓疾病显微手术中的监测作用 ,避免或减少医源性脊髓损伤。方法　 2 8例病人行术前、术中SEP全程监测 ,包括脊髓SEP(SSEP)及皮层SEP(CSEP) ,术中及时把监测信息反馈给术者。并将术中监测结果与术后疗效对照分析。结果　椎管内占位手术在行髓内肿瘤切除时最易引发SEP波幅降低及潜时延长。术中监测按Frankel分级D、E级患者波幅较基准电位下降不超过 50 % ,潜伏期延长不超过7% ;B、C级患者波幅较基准电位下降不超过 40 % ,潜伏期延长不超过 5 %。术后不会引起脊髓功能不可逆损害。结论　脊髓手术时行SSEP和CSEP联合监测可及时反映出脊髓功能的变化 ,提高术者术中操作的安全性 ,避免或减少术后并发症     

脊髓萎缩（附2例报告）

本文报告了两例脊髓萎缩，并结合文献复习讨论了该病的好发部位、病因、临床表现、诊断和治疗。脊髓萎缩的病因多为继发性，也可为特发性。根据临床表现结合脊髓ＣＴ造影及ＭＲＩ检查，可以明确诊断。     

Bone mineral status in paraplegic patients who do or do not perform standing

Bone mineral density (BMD) was assessed by dual-photon X-ray absorptiometry at the lumbar spine (L3, L4), the proximal femur and the femoral shaft, and by single-photon absorptiometry at the forearm in 53 patients with complete traumatic paraplegia of at least 1 year's duration and in age- and sex-matched healthy controls. The patients did (n=38) or did not (n=15) regularly perform passive weightbearing standing with the aid of a standing device. Compared with the controls, the BMD of paraplegic patients was preserved in the lumbar spine and was markedly decreased in the proximal femur (33%) and the femoral shaft (25%). When considering all patients performing standing, they had a better-preserved BMD at the femoral shaft (p=0.009), but not at the proximal femur, than patients not performing standing. BMD at the lumbar spine (L3,L4) was marginally higher in the standing group (significant only for L3;p=0.040). A subgroup of patients performing standing with use of long leg braces had a significantly higher BMD at the proximal femur than patients using a standing frame or a standing wheelchair (p=0.030). The present results suggest that passive mechanical loading can have a beneficial effect on the preservation of bone mass in osteoporosis found in paraplegics.     

NMDA Receptor Activation Triggers Voltage Oscillations, Plateau Potentials and Burstinq in Neonatal Rat Lumbar Motoneurons ln Vitro

Whole-cell recordings of lumbar motoneurons in the intact neonatal rat spinal cord in vitro were undertaken to examine the effects of Kmethyl-D-aspartate (NMDA) receptor activation on membrane behaviour. Bath application of NMDA induced rhythmic voltage oscillations of 5.9 ± 2.1 mV (SD) at a frequency of 4.4 ± 1.5 Hz. Amplitude, but not frequency, of the voltage oscillations was membrane potential-dependent. Voltage oscillations could recruit action potentials and/or plateau potentials with or without superimposed bursting. Blockade of synaptic transmission with tetrodotoxin (TTX) sometimes resulted in a loss of oscillatory activity which could then be restored by increasing the NMDA concentration. After application of TTX, the trajectory of NMDA-induced oscillations was similar to the trajectory induced in the presence of intact synaptic networks, although the mean oscillation duration was longer and the oscillation frequency was slower (1.8 ± 1.1 Hz). Current ramps delivered after bath application of NMDA demonstrated bistable membrane properties which may underlie the plateau potentials. Injection of intracellular current pulses could initiate, entrain and terminate individual plateau potentials. The results suggest that membrane depolarization produced by oscillations may activate other intrinsic conductances which generate plateau potentials, thereby providing the neuron with enhanced voltage sensitivity, compared to that produced by NMDA receptor activation alone. These oscillatory events may have a role in the regulation of motor output in a variety of rhythmic behaviours including locomotion.