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11.
螺旋神经节神经元原代培养及其免疫细胞化学鉴定   总被引:8,自引:1,他引:7  
目的 建立成体哺乳动物耳蜗螺旋神经节神经元(SGN)体外培养的细胞模型。方法 对出生后7d的Wistar大鼠的螺旋神经节细胞进行解离与分散培养。用荧光显微镜与倒置相差显微镜观察原代培养SGN细胞的活力以及生长与分化过程。应用链霉卵白素过氧化物酶(SP)方法和抗神经丝蛋白单克隆抗体(NFP-McAb)对SGN进行免疫细胞化学染色鉴定。结果 幼龄Wistar大鼠的SGN在体外条件下,可良好存活并有正常  相似文献   
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As a part of our ongoing study on Alzheimer's disease (AD) in elderly African Americans, we obtained clinical assessment and apolipoprotein E (ApoE) genotype data on 288 individuals (including 60 with AD). The ApoE σ4 allele frequency was significantly increased in AD patients compared with controls. The age-adjusted odds ratio (OR) for AD in σ4 homozygotes was 4.83 (95% confidence interval [CI], 1.71–13.64) compared with the σ3/σ3 genotype, but the OR for AD with the σ3/σ4 genotype did not reach significance (1.20; 95% CI, 0.58–2.45). These findings suggest that the association between ApoE σ4 and AD is weaker in African Americans than in whites.  相似文献   
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四叠体池蛛网膜囊肿   总被引:2,自引:0,他引:2  
目的:探讨四叠体池蛛网膜囊肿的临床特征和治疗方法。方法:对11例四叠体池蛛网膜囊肿进行了回顾性总结分析。所采用的手术方法有:①脑室分流手术;②囊肿-腹腔分流术;③囊肿切除;④囊肿切除加囊肿-脑池分流术,或囊肿部分切除(即囊肿开窗术),或囊肿切除加脑室-脑池分流术。结果:其主要临床表现以颅内压增高症和中线综合征为主。上述方法中单纯囊肿壁切除只能使部分病人的病情缓解,脑室分流或囊肿切除加脑室分流手术的疗效较好。结论:四叠体区蛛网膜囊肿常合并梗阻性脑积水,单纯囊肿切除不能解除多数病人的梗阻性脑积水。作者根据囊肿是否与蛛网膜下腔相通提出:对交通性蛛网膜囊肿采用单纯性脑室分流术,对非交通性者采用囊肿切除加脑室分流手术的治疗方法。  相似文献   
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Abstract The aim of this study was to describe the periodontal conditions in 372 35–44-yr-old and 537 noninstitutionalized 65–74-yr-old Hong Kong Chinese who were examined clinically for loss of attachment, recession, probing depth, calculus, and bleeding after probing. Community Periodontal Index (CPI) data and treatment need indications were compiled from index teeth or their substitutes. The prevalence of loss of attachment varied considerably in both cohorts according to the definition of the threshold (≥6, ≥9, and ≥12 mm, respectively). The mean numbers of teeth with loss of attachment at the ≥6-mm threshold and at higher thresholds were small. In both age cohorts, about one-fifth of subjects had probing depths ≥6-mm, while al the ≥9-mm threshold only 2–3% were so affected. Although recession was an important component of loss of attachment in the younger cohort, in the older cohort the prevalence and extent of recession were greater than for probing depths at thresholds ≥4 mm. All subjects had one or more teeth with calculus, bleeding, or both, most teeth being so affected. Eighty-four of the 537 65–74-yr-old subjects were excluded either because of edentulousness or because extractions indicated for the remaining teeth would have rendered the subjects edentulous. The distribution of subjects according to their highest CPI score was remarkably similar for the two cohorts. No subjects in either age group were assessed as “healthy” (CPI code 0) or had “bleeding only” (code 1) as their highest score. While most subjects scored CPI code 2 or 3 us their highest score, only 17% of the younger and 15% of the older cohort scored Community Periodontal Index of Treatment Needs (CPITN) code 4. Differences in the mean number of sextants affected by CPI codes between the two cohorts were mainly due to a greater number of excluded sextants in the older cohort. CPI findings for 35–44-yr-olds differed little from those reported in 1984.  相似文献   
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目的:利用单光子发射计算机断层摄影(SPECT)半定量分析有效控制与控制不良的MRI阴性的全面性强直阵挛发作癫(GTCS)病人的局部脑血流差异,探讨脑血流灌注与其预后的关系.材料和方法:对29例有效控制的和12例控制不佳的MRI阴性的GTCS病人进行发作间期99mTc-ECD-SPECT脑血灌流显像,10例年龄匹配的健康人作对照,用感兴趣区(ROI)的不对称指数(%AI)进行半定量分析.将SPECT分析结果与病人的临床表现与EEG相比较.结果:①控制不佳组与有效控制组在丘脑和基底节区的%AI存在显著性差异(P<0.05);②控制不佳组SPECT脑显像的异常率(83.3%,10/12)明显高于有效控制组的异常率(17.2%,5/29),两组具有显著性差异(P<0.01);而两组病人的EEG异常率分别为58.3%、44.8%(7/12、13/29),无显著性差异(P>0.05).结论:控制不佳的MRI阴性的GTCS病人往往存在发作间期的低血流灌注脑区,提示癫的难治性;而控制良好的病人多无明显异常发现,可能预后较好.  相似文献   
18.
OBJECTIVE: Many patients with haemorrhoids are investigated because of the fear of missing colorectal cancer (CRC). The aim of this study was to determine whether a primarily clinical approach regarding the need for investigation was safe and did not miss patients with CRC. PATIENTS AND METHODS: Data was collected prospectively on 589 consecutive patients with the principle diagnosis of haemorrhoids at first clinic visit. All had clinical assessment including rigid sigmoidoscopy and were treated by phenol injection or banding. They were categorized for (1) no review unless symptoms persisted -'One Stop SOS' (2) outpatient review or (3) investigation. To check for the development of CRC they were contacted by postal questionnaire or telephone interview with a minimum of one year from diagnosis and treatment. All 589 patients were cross-referenced with the Pathology database and the Hospital Information Services System. RESULTS: Four hundred and sixty-nine (80%) answered the questionnaire; 352 patients (60% of the total group) fell in the 'one stop SOS' outpatient category; 95 (16%) patients were followed up to review response to treatment for large haemorrhoids; 105 (18%) were investigated with barium enema (12%), flexible sigmoidoscopy (4%), colonoscopy (1%) and miscellaneous (1%); 37 (6%) patients were either given a haemorrhoidectomy date or referred on with a different diagnosis. No patients selected for 'one-stop' treatment developed CRC. Five (0.8%) patients were diagnosed with CRC after appropriate investigation was instituted for suspicious symptoms. One patient with distal transverse colon cancer had a delayed diagnosis as she was investigated initially by flexible sigmoidoscopy. CONCLUSION: Most patients with the primary diagnosis of symptomatic haemorrhoids do not need investigation.  相似文献   
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目的 为研究皮肤疾病和损伤提供皮神经构筑资料。方法 用S 10 0蛋白免疫组化染色法研究正常成人颈前部胸锁乳突肌前、后缘皮肤各层内皮神经的数量、分布及构筑特点。结果  ( 1)皮肤乳头层内皮神经的小分支多分布在皮突下和乳头内血管丛附近。 ( 2 )真皮网状层内神经多位于小血管附近和汗腺、皮脂腺以及毛囊周围 ,神经分支呈串珠状或波纹形。 ( 3 )皮下组织内神经干和神经网同时存在。结论 皮肤内感觉神经树的分布及构筑特点与血管树相似。  相似文献   
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