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31.
32.
脊髓损伤大鼠的阴茎海绵体肌电图研究 总被引:2,自引:0,他引:2
目的探讨海绵体肌电图诊断脊髓性勃起功能障碍的价值。方法将24只成年雄性SD大鼠(300~400 g)分成:对照组、T9和L6损伤组(每组8只)。损伤脊髓1周后,用肌电图仪采集注射阿朴吗啡前后阴茎肌电数据,采集频率20~3 000 Hz、扫描速度5 ms/d、灵敏度10 μV/d。用t检验方法分析统计数据。结果对照组使用阿朴吗啡10 min均方根振幅为(5.60±0.89)μV, 大于T9损伤组(3.60±1.14)μV(P<0.05);使用阿朴吗啡前、使用后5 min和10 min高/低功率比均为0.05±0.03,小于L6损伤组0.13±0.04、0.15±0.07、0.13±0.07(P<0.05)。T9损伤组使用阿朴吗啡后5 min和10 min平均频率分别为(122.40±47.99)、(151.80±76.42)Hz,较L6损伤组(278.83±118.66)、(265.00±81.35)Hz低(P<0.05)。结论海绵体肌电图对脊髓性勃起功能障碍有诊断价值。 相似文献
33.
睾丸扭转和精索扭转的诊断与治疗(附68例报告) 总被引:9,自引:0,他引:9
目的:探讨睾丸和精索扭转的诊断与治疗方法,提高睾丸和精索扭转的治疗水平。方法:对68例睾丸和精索扭转的临床资料进行总结,68例平均年龄21岁,<20岁者占84%,左侧55例占80.8%.发病至确诊时间6h~30天,12h以上者占90.2%。结果:53例术前彩色多普勒血流动态显象(CDFI)应作为诊断疾病的常见与首选检查方法。诊断并经手术证实,符合率100%,经手术探查;41例行手术复位、固定,睾丸获救。27例行患侧睾丸切除术,所有病例均行对侧探察,固定。结论:阴囊X核素显象,B超对睾丸精索扭转早期诊断有帮助。早期诊断,及时治疗是提高疗效的关键。彩色多普勒血流动态显象应作为诊断该疾病的常见及首选检查方法,对睾丸精索一旦确诊或疑有精索扭转的患者应及早行紧急复位,以期挽救睾丸,同时行睾丸固定术也十分必要。对于确诊毫无保留价值的睾丸需行切除术。 相似文献
34.
目的研究坐骨神经慢性挤压伤(chronicconstrictioninjury,CCI)后不同时点大鼠脊髓磷酸化cAMP反应成分结合蛋白(p-CREB)含量的变化。方法32只160~180g雄性SD大鼠中,8只为正常对照,其余24只做成CCI模型。用VonFrey细丝测定大鼠后爪触诱发痛的变化,并于术后7、14和30d处死(n=8),取L4~L6脊髓用以免疫印迹(Westernblot)方法测定p-CREB的表达量。结果CCI大鼠结扎侧在术后7、14d出现明显的机械感觉异常(P<0·01),30d后基本消失。与正常大鼠相比,CCI大鼠p-CREB含量在术后7、14d均出现明显升高(P<0·01),术后30d恢复到正常水平。结论CCI大鼠疼痛模型中脊髓p-CREB含量明显增高,并且随疼痛症状消失恢复到正常水平。提示脊髓p-CREB在慢性神经性疼痛中发病机制中有一定的作用。 相似文献
35.
Qi-Yue DENG Shu-Rong LI Wen-Qin CAI Bing-Yin SU Department of Neurobiology Third Military Medical University Chongqing China Department of Neurobiology Chengdu Medical College Chengdu China Department of Histology Embryology Chengdu Medical College Chengdu China 《中国神经科学杂志》2006,(2)
Objective To investigate the role of poly-lactic acid and agarose gelatin in promoting the functional recovery of the injured spinal cord. Methods Poly-lactic acid ( PLA) or agarose was embedded in the space between two stumps of the hemisectioned spinal cord. Immunohistochemistry was used to show astroglia proliferation and the infiltration of RhoA-positive cells. Locomotor activity recovery was evaluated by testing the function of hindlimbs. Results Astrogli-as and RhoA labeled non-neuronal cells accumulated in the area adjacent to the implant, while the number of RhoA-positive cells was decreased dramatically in the absence of implant. Animals implanted with agarose gelatin recovered more quickly than those with PLA, concomitant with a higher survival rate of the neurons. Conclusion Both PLA and agarose gelatin benefited the recovery of spinal cord after injury by providing a scaffold for astroglia processes. Modulation of the rigidity, pore size and inner structure of PLA and agarose gelatin might make these biodegradable materials more effective in the regeneration of the central nervous system (CNS). 相似文献
36.
JUHANI RINNE 《Clinical otolaryngology》1991,16(5):436-441
Thirty-four patients with bilateral vocal cord abductor paralysis were treated surgically during the period from 1960 to 1979. The main cause of paralysis was thyroid surgery (85%). Woodman's external laterofixation was performed in 31 patients, 1 had laterofixation by laryngofissure and 2 had endoscopic arytenoidectomy. In Woodman's procedure the body of the arytenoid cartilage was removed in 10 cases and mobilized from the cricoarytenoid joint in 21 cases. Thirteen of the 34 patients needed further surgery. Including previously performed procedures in 6 patients, altogether 68 operations were performed and 17 patients (50%) were operated on more than once. The immediate failure rate of laterofixation was 22% but the need for reoperation increased with time and the total failure rate of the method was 44%. Endoscopic arytenoidectomy was successful in 1 of 2 cases as a primary operation and in 3 of 3 cases as secondary operation. Follow-up time ranged from 2 months to 29 years 8 months (mean 15 years 10 months). 相似文献
37.
We report the case of a thoracic epidural hematoma at the T7-T9 level which occurred after placement of spinal epidural catheter for continuous anaesthesia in acute pancreatitis. The male patient felt a sudden back pain after six days of successful analgesia and became paraplegic 24 hours afterwards. An emergency laminectomy and removal of the hematoma were performed; however, the patient recovered only incompletely.We discuss the clinical signs and symptoms of spinal epidural hematoma as well as its diagnostics and therapy. The controversial views from the literature concernings its etiology are critically reviewed. 相似文献
38.
Several studies have demonstrated that a descending dopaminergic pathway innervates the dorsal and the intermediate gray matter of the spinal cord and have suggested that this pathway is involved in pain modulation and in the control of autonomie functions. Other studies have also demonstrated the presence of dopamine (DA) and DA metabolites as well as of DA receptors in the ventral cord. There is also evidence for the implication of DA in the control of motor functions at the spinal level. The occurrence of a dopaminergic innervation in the ventral horn has been, however, disputed until recently. But recent work has demonstrated that the motoneural cell groups in the ventral horn (lamina IX) are a target for descending dopaminergic fibers. In addition, the possibility that DA is a mediator of primary afferent fibers has also been postulated. Finally, the occurrence of dopaminergic cell bodies has been suggested in the spinal cord. This indicates that DA is probably implicated in a complex manner in spinal functions. In the present paper the possible involvement of DA in sensory and in motor functions at spinal level will be discussed in view of neurochemical observations made in polyarthritic rats, in which pain-related behavior and reduction of locomotor activity associated with a marked decrease in mobility, are observed. 相似文献
39.
R. N. KALARIA ‡‡ P. G. GALLOWAY† G. PERRY‡ ‡‡ 《Neuropathology and applied neurobiology》1991,17(3):189-201
Amyloid P (AP) component is present in all types of systemic amyloid deposits. Recently, it has been shown to be also present in cerebral amyloid lesions of Alzheimer's disease (AD). In this study, we used immunocytochemical methods to extend these findings at the electron microscope level and characterize the spectrum of AP immunoreactivity in neurofibrillary pathology (NFP) of AD and other neurodegenerative disorders including Down's syndrome (DS), Creutzfeldt-Jakob, Parkinson's, Pick's and diffuse Lewy body diseases and progressive supranuclear palsy. In AD and DS, AP immunoreaction product was evident in all the classical amyloid lesions and NFP in a large sample of all cortical areas examined. The distribution and relative intensity of immunostaining was similar to that of thioflavin S staining in serial sections. In many cases, however, plaques and vessels stained by anti-AP serum were not apparent with thioflavin S. Serial sections immunostained with antiserum to amyloid A, C-reactive protein or to other proteins involved in systemic amyloidoses and the acute phase response showed no evidence of staining in any of the cerebral lesions. Electron microscopy confirmed that AP immunoreactivity was associated with the abnormal filaments characteristic of NFP as well as amyloid fibrils found in plaques and vessels showing congophilic amyloid angiopathy. Plaques of Creutzfeldt-Jakob disease, Pick bodies of Pick's disease, tangles and Lewy bodies in Parkinson's disease and a subpopulation of Lewy bodies in the diffuse Lewy body disease coexistent with AD were also stained. With the exception of vessels in two of the five cases, AP was not detected in age-matched controls. Our observations indicate AP to be a consistent feature of cerebral NFP and amyloid deposits. 相似文献
40.
The formation of the blood-testis barrier (BTB) in the domestic fowl was studied at the electronmicroscopic level employing lanthanum as a tracer. No effective barrier could be demonstrated in testes before puberty, although several components of the Sertoli junctional complex such as focal tight junctions and desmosomes were already existent. The time of onset of meiosis after hatching showed great individual variation and meiosis did not occur synchronously in the tubules of a given testis. An effective barrier could first be detected in tubules containing early spermatids, and in which spermatogonia and primary spermatocytes at the leptotene stage were still within the open compartment. Thus, barrier formation was correlated with the occurrence of haploid germ cells. Complete compartmentation of seminiferous tubules, leaving only spermatogonia within the open compartment, was attained in tubules containing elongated spermatids of the maturation phase. In these tubules, primary spermatocytes at the leptotene stage were situated in an intermediate compartment. 相似文献