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131.
A neuropathological study on 1540 consecutive autopsy brains ranging from 60 to 107 years of age revealed the following points. (1) Of the of the demented cases of the plaque-predominant type, 93% were complicated with multiple tiny cortical infarcts. They showed a tendency for dementia to develop before or after the appearance or worsening of a systemic disorder such as cardiovascular disease, respiratory infection and cancer. However, there was no case showing Alzheimer-type dementia (ATD). (2) The plaque-predominant type might be an extreme condition of brain aging in terms of senile plaques (SP). It is likely that although the pathological appearance of SP alone is not responsible for dementia, its coexistence with multiple cortical infarcts could be the cause of dementia. Therefore, this type should be distinguished from ATD. (3) Primary hippocampal degeneration could also be an extreme condition of brain aging in terms of neurofibrillary tangles. This condition was different pathologically from the hippocampal lesion in ATD. (4) Several characteristics of old-old and oldest-old patients were clarified.  相似文献   
132.
颈椎间盘突出的MRI诊断价值(附41例分析)   总被引:5,自引:1,他引:4  
目的:探讨颈椎间盘突出的MRI诊断。方法:对41例椎间盘突出进行磁共振成像检查。结果:表明本病可分为中央型和侧方型突出。MRI可直接显示颈椎间盘突出的部位、类型及颈髓和神经根的受压程度。结论:MRI对本病的确诊具有重要价值  相似文献   
133.
探讨螺旋CT引导下射频热凝联合臭氧消融治疗腰椎间盘突出症日间手术的临床疗效。方法 回顾性收集2020年1月—2022年6月我院日间病房住院的137例腰椎间盘突出症患者的临床资料,所有患者均行螺旋CT引导下射频联合臭氧消融治疗日间手术。收集手术时间,术毕至出院时间,总住院时间,术前、术后1月、3月的疼痛数字评分(NRS),Oswestry功能障碍指数(ODI)评分,改良 Macnab评级和手术相关并发症,并进行术前与术后的对比分析。结果 所有患者在螺旋CT引导下穿刺成功率为100%,并在手术当日出院,平均手术时间为(35.55±10.44)min,平均术毕至出院时间为(58.36±25.26) min,平均总住院时间为(453.91±27.18)min。术后1、3月的NRS评分和ODI评分均低于术前;术后1、3月改良Macnab疗效评定标准有效率分别为86.13%、89.05%。所有患者均未有穿刺或治疗相关的并发症。结论 螺旋CT引导下射频联合臭氧消融治疗腰椎间盘突出症日间手术是可行的,其可降低腰椎间盘突出症患者的疼痛程度、改善日常功能障碍、安全性高,可在临床推广应用  相似文献   
134.
目的 探究腰椎间盘突出症(LDH)与阻塞性睡眠呼吸暂停(OSA)之间的关联,为LDH的临床诊治策略及治疗方案提供参考依据。方法 选取2018年1月—2020年3月中国医科大学附属第一医院骨科行外科手术治疗的485例LDH患者,按是否合并OSA进行分组研究。结果 485例LDH患者中合并OSA的307例,发生率为63.3%。LDH合并OSA组主观症状、临床症状、日常活动受限程度日本骨科协会(JOA)腰痛评分低于单纯LDH组(P <0.05);两组膀胱功能JOA评分比较,差异无统计学意义(P> 0.05);LDH合并OSA组视觉模拟评分法(VAS)评分高于单纯LDH组(P <0.05)。Pfirrmann 5级评分法中4、5级例数构成比LDH合并OSA组较单纯LDH组高(P <0.05)。两组患者的硬膜撕裂率、神经受损率、血肿率、切口感染率等并发症发生率比较,差异无统计学意义(P>0.05)。单纯LDH组与LDH合并OSA组术后3、6、12和24个月静息状态下JOA和VAS评分比较,采用重复测量设计的方差分析,结果:(1)不同时间点的JOA和VAS评分有差异(...  相似文献   
135.
Summary We describe two patients with sporadic amyotrophic lateral sclerosis (ALS), who had developed progressive external ophthalmoplegia of a predominantly supranuclear type while they survived on respirators, and displayed histopathological abnormalities both typical and atypical of ALS. Patient 1 was a 43-year-old man with ALS of 5-year duration, who had initially exhibited fulminant ALS, and remained on a respirator for 4 years. Patient 2 was a 51-year-old man with ALS of 13-year duration, who remained on a respirator for 8 years. Both patients died in a totally locked-in state. Autopsy of both patients revealed not only histopathological abnormalities consistent with ALS, but also multisystem degeneration which involved the pontine tegmentum, substantia nigra, Clarke's dorsal nuclei and spinocerebellar tracts. In addition, Patient 2 displayed intracyto-plasmic neuronal basophilic inclusion bodies which exhibited marked immunoreactivity to anti-ubiquitin antibodies. Our case reports indicate that the longer survival which is possible through the use of respirators may make one subgroup of ALS patients prone to develop atypical clinical and neuropathological features which are not observed during the natural cours of ALS.Supported by a Grant-in-Aid from the Research Committee of CNS Degenerative Diseases, the Ministry of Health and Welfare of Japan, and by a Grant from Nihon University School of Medicine, Tokyo  相似文献   
136.
Electrophysiological properties were monitored in detail in chronically constricted peripheral nerves by implanted, multicontact nerve cuff electrodes and correlated with morphometric histology in selected cases. The physiological and histological responses in nerve to a range of constricting cuffs of standard sizes were readily graded. The initial response to any significant constriction was a transient, focal conduction slowing or block at the constriction, followed by more protracted distal effects; the latter ranged from loss of excitability consistent with "dying-back" degeneration to reductions in conduction velocity consistent with histologically observed atrophy. Smaller myelinated fibers tended to have similar but less pronounced changes than larger diameter fibers. Recordings from ventral and dorsal roots showed that distal degeneration was more pronounced in motor than in sensory fibers of similar caliber. Electronmicroscopical measurements showed that basal laminas were relatively preserved around even the most atrophic and demyelinated axons. Perimeter measurements of the basal lamina could be used to estimate the diameter of the original nerve fiber.  相似文献   
137.
During (January) 1986–(May) 1988, we examined 272 eyes in 136 rhesus monkeys in the closed Cayo Santiago colony of the Caribbean Primate Research Center of the University of Puerto Rico. Seventy-eight eyes were less than 10 years of age. One hundred and ninety-four were aged 10–28 years. The fundi were examined and photographed. Fluorescein angiography was performed in some eyes. Selected cases were evaluated for acuity loss by recording of pattern-evoked retinal and cortical signals. Light and electron microscopy were used to evaluate the pigment epithelium of some animals. Thirty-eight percent of all eyes had posterior pole drusen. Incidence was highly age-related. When late-stage lesions were found, we did not see neovascularization, but late hyperfluorescence was consistent with degenerative scarring and atrophy. Electrophysiology demonstrated moderately reduced acuity in the presence of numerous macular drusen. Electrooculograms were low normal. Histopathology showed changes identical to those reported in human age-related macular degeneration. No eyes less than 10 years of age had confluent drusen or disciform-like lesions. The incidence of drusen in samples of some social groups was much higher than others.  相似文献   
138.
兔腰椎间盘退变模型的建立及影像学分析   总被引:9,自引:3,他引:9  
目的:建立腰椎间盘退变的动物模型并进行CR和MRI观察.方法:选用新西兰兔20只,沿右腹直肌外缘做15 cm长切口,钝性剥离腹膜至腰椎横突前外侧,咬除右侧L5、L6横突,显露上述节段椎间盘,斜形切开纤维环约1.5 mm,未伤及髓核,然后逐层缝合.所有动物在标准条件下饲养,分别于术后2、4、8、20、40周行腰椎计算机x线摄影术(CR)和核磁共振成像(MRI)以检测终板下骨及髓核的变化.结果:术后作为自体对照组的L1、2、L2、3椎间盘未见异常,而手术组L4、5、L5、6椎间盘则相继出现T2加权像低信号、腰椎不稳畸形,终板下骨质硬化,椎体边缘骨赘增生,椎间隙变窄,椎间盘后突和硬膜囊受压等改变.对手术节段及其邻近和完全正常节段椎间盘髓核信号值的定量分析显示,手术组椎间盘T2加权像信号值减低在术后4、8、20、40周与正常对照组对比具有统计学意义,而临近椎间盘L3、4、L6、7手术8周后与正常椎间盘对比有显著差异.CR扫描结果显示:手术节段椎间盘终板下信号值减低与对照组相比4周后就开始有显著差异.结论:应用纤维环切开法可获得可靠的新西兰大白兔椎间盘退变模型,可通过MRI及CR在早期加以证实.  相似文献   
139.
Unrelated patients with achromatopsia, macular degeneration with onset under age 50 years, cone degeneration or dysfunction, cone-rod degeneration, or macular malfunction were screened for mutations in the three genes known to be associated with achromatopsia: the GNAT2 gene encoding the alpha subunit of cone transducin and the CNGA3 and CNGB3 genes encoding the alpha and beta subunits of the cone cGMP-gated cation channel. We found no examples of patients with GNAT2 mutations. Out of 36 achromats, 12 (33%) had mutations in CNGA3 (13 different mutations including five novel mutations) and 12 (33%) had mutations in CNGB3 (six different mutations including four novel mutations). All achromats with CNG mutations had residual, presumably cone function as determined by computer-averaged 30-Hz electroretinograms (ERGs). There was considerable variability in acuity and color vision, with most patients having acuities of 20/200-20/400 and complete absence of color perception, and others having acuities of 20/25-20/40 and some color vision. Two pseudodominant achromatopsia cases were uncovered, both with CNGA3 mutations, including one family in which some compound heterozygotes with achromatopsia mutations were clinically unaffected. We found two novel CNGB3 changes in three patients with juvenile macular degeneration, a phenotype not previously associated with mutations in the cone channel subunits. These patients had subnormal acuity (20/30-20/60), normal to subnormal color vision, and normal to subnormal full-field cone ERG amplitudes. Our results indicate that some patients with channel protein mutations retain residual foveal cone function. Based on our findings, CNGB3 should be considered as a candidate gene to be evaluated in patients with forms of cone dysfunction, including macular degeneration.  相似文献   
140.
The effects of pinealectomy and administration of melatonin, the major secretory product of the pineal gland, which is a direct free radical scavenger and an indirect antioxidant, were studied in rat hearts on the basis of cardiac morphology and biochemical findings. Three groups of Wistar rats were used: one group was the sham-operated control, one group consisted of pinealectomized rats and one group consisted of pinealectomized rats that were treated with melatonin. Serum cholesterol, tissue levels of malondialdehyde (MDA) and reduced glutathione (GSH), and heart weight were determined. Histochemical staining with the Van Gieson, PAS/Alcian blue at pH 2.5 and Masson's trichrome methods were performed in addition to hematoxylin-eosin staining. Levels of serum cholesterol and tissue MDA, and heart weight were increased in pinealectomized rats whereas GSH levels did not change. Melatonin administration reversed these effects. Microscopically, myocardial fibrosis and myxomatous degeneration of cardiac valves were detected in all pinealectomized rats. It can be concluded that pinealectomy of rats causes morphological changes in rat hearts, and short-term application of melatonin does not reverse these changes.  相似文献   
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