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71.
Autoradiography and anterograde horseradish peroxidase transport were used to examine retinocollicular projections in normal hamsters and in animals subjected to ablation of the ipsilateral, posterior neocortex at 1, 3, 6, 10 or 120 days of age. The crossed retinotectal projections of all groups were quite similar. There did, however, appear to be a slight increase in the density of the projection to the lower portion of the stratum griseum superficiale in the neonatally brain-damaged hamsters.The uncrossed pathway, on the other hand, was quite abnormal in the neonatally lesioned animals. In normals, the ipsilateral retinocollicular projection consisted almost entirely of a series of patches along the stratum yriseum superficiale-stratum opticum border in the rostral one-third of the colliculus. Only a few axons from the ipsilateral eye were observed in the caudal two-thirds of the tectum and these could only be visualized when horseradish peroxidase was used as the tracer. In all of the neonatally brain-damaged hamsters both autoradiography and horseradish peroxidase tracing demonstrated that the ipsilateral retina densely innervated the entire rostrocaudal extent of the colliculus.Retrograde tracing experiments demonstrated that the portion of the temporal retina which gave rise to the uncrossed retinocollicular projection in the normal hamsters was also the source of the expanded projection in the neonatally brain-damaged animals; and, further, that the numbers and areal distributions of ipsilaterally projecting retinal and retinocollicular ganglion cells were similar in the two groups.These findings suggest that, at least in the hamster, normal inputs from the two eyes may not be a sufficient condition for the development of the largely complementary pattern of collicular innervation by the two retinae.  相似文献   
72.
小脑梗死的临床研究现状   总被引:5,自引:0,他引:5  
小脑动脉属椎、基底动脉的长旋支 ,供血范围主要包括小脑、脑干外侧部及被盖部。小脑梗死好发于 6 0~ 80岁男性 ,根据影像学改变可分为区域性和非区域性两大类。缺血机制不同 ,临床表现及预后差异较大。本文重点阐述小脑梗死的发病机制、各小脑动脉闭塞时的临床 -解剖相关性和预后。  相似文献   
73.
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   
74.
经皮腰椎间盘切除术治疗复发性腰椎间盘突出症   总被引:1,自引:0,他引:1  
目的:总结经皮腰椎间盘切除术治疗传统后路术后复发性腰椎间盘突出症的经验。方法:分析1995年1月至1998年12月采用经皮腰间盘切除术治疗19例复发性腰椎间盘突出症的临床资料。结果:穿刺成功率100%,术后随访10~32月,平,平均21月,优11例、良5例,可2例,差1例,优良率84.2%。结论:在具有再次开放手术适应症的复发性腰椎间盘突出症中,初次手术行单节段半椎板、全椎板切除和开窗术者中一侧单  相似文献   
75.
Torres JC 《Obesity surgery》1994,4(3):279-284
Selective proximal vagotomy and posterior truncal vagotomy have been performed in 71 consecutive gastric bypass (GBP) patients from June 1991 to December 1992. Vagotomy was used to prevent or diminish the incidence of marginal ulcer in GBP patients. Anterior and posterior highly selective proximal vagotomy with circular-instrument stapled gastrojejunostomy in patients undergoing GBP distal Roux-en-Y with jejunal interposition had no marginal ulcer complications (minimal follow-up 18 months).  相似文献   
76.
77.
Mingxing  Wu  Huaming  Li 《眼科学报》1999,15(1):55-60
Purpose: To investigate whether liposome encapsulated total alkaloid of Harmaline (TAH) as a therapeutic agent is beneficial to prevention of posterior capsular opacifi-cation (PCO).Methods: Liposome-encapsulated TAH was prepared by modified freeze-thawing method. 0. 1ml of liposome-encapsulated TAH (0. 2mg/ml) was injected into the capsular bag during extracapsular lens extraction (ECLE) of each eye in total 10 rabbit eyes. Blank liposome or balance salt solution (BSS) was used as control. Slit-lamp examination and histopathological examination was used to evaluated capsule opacifica-tion. Intraocular pressure (IOP) , density and morphology of corneal endothelia cells, the amplitude and latency of b wave of ERG were measured.Results: The inflammatory response was mild both in TAH treated and the control group. PCO formation occurred in the control group 2 weeks postoperatively, but the posterior capsule was clear in TAH treated eyes. 4 weeks and 8 weeks after operation, PCO occurred both in TAH treated  相似文献   
78.
后巩膜加固术对视网膜振荡电位的影响   总被引:3,自引:0,他引:3  
目的 为了更进一步地了解后巩膜加固术治疗高度进行性近视的疗效和机理。方法 采用日本产Neuropack Four 4104 K 电生理仪,对26 例52 眼高度进行性近视行后巩膜加固术前、术后视网膜振荡电位进行定量分析。结果 术前、术后振荡电位总振幅经统计学处理有非常显著性差异,波的潜伏期无显著性差异。结论 本文认为后巩膜加固术可改善视网膜血液循环,并对机理进行了探讨  相似文献   
79.
By comparing the incidence of cystoid macular edema (CME) in three groups of patients having different surgical procedures, we attempted to assess the role of vitreous loss as a risk factor for CME development. In the first group (n = 470), the surgical procedure was extracapsular cataract extraction followed by implantation of posterior chamber lens (EC-CE + PC-IOL). The second group (n = 42) had extracapsular cataract extraction which was complicated by posterior capsule rupture, and therefore anterior vitrectomy followed by implantation of anterior chamber lens had to be performed (ECCE + anterior vitrectomy + AC-IOL). In the third group (n = 22) the surgery was intracapsular cataract extraction followed by anterior chamber lens implantation (ICCE + AC-IOL). The third group was included in this follow up study to assess the role of AC-IOL as a possible causative factor for development of CME in uncomplicated cases of ICCE and AC-IOL. The difference of incidences of CME in the second and third group would therefore depend mostly on the vitreous loss. The incidence of CME diagnosed by fluorescein angiography in the first, second and third group was 1.5% (7/470), 35.7% (15/42) and 9.0% (2/22), respectively. All patients who developed CME were treated with combination of corticosteroid-antibiotic drops, dexamethasone retrobulbarly (40 mg/day) and peroral indomethacine (25 mg/day/6 weeks). This therapeutic regime resulted in only moderate improvement of visual acuity.Abbreviations AC-IOL anterior chamber intraocular lens - CME cystoid macular edema - ECCE extracapsular cataract extraction - ICCE intracapsular cataract extraction - IOL intraocular lens - PC-IOL posterior chamber intraocular lens  相似文献   
80.
Clinical features and surgical outcome of 16 patients with dermoid or epidermoid cysts on the midline of the posterior cranial fossa are compared. Salient points in the comparison are the younger age, presence of associated malformations and better prognosis of dermoid cyst.  相似文献   
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