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71.
David M Raffel Robert A Koeppe Roderick Little Chia-Ning Wang Suyu Liu Larry Junck Mary Heumann Sid Gilman 《Journal of nuclear medicine》2006,47(11):1769-1777
Scintigraphic imaging with (123)I-metaiodobenzylguanidine ((123)I-MIBG) has demonstrated extensive losses of cardiac sympathetic neurons in idiopathic Parkinson's disease (IPD). In contrast, normal cardiac innervation has been observed in (123)I-MIBG studies of multiple-system atrophy (MSA) and progressive supranuclear palsy (PSP). Consequently, it has been hypothesized that cardiac denervation can be used to differentiate IPD from MSA and PSP. We sought to test this hypothesis by mapping the distribution of cardiac sympathetic neurons in patients with IPD, MSA, and PSP by using PET and (11)C-meta-hydroxyephedrine ((11)C-HED). Also, the relationship between cardiac denervation and nigrostriatal denervation was investigated by measuring striatal presynaptic monoaminergic nerve density with PET and (11)C-dihydrotetrabenazine ((11)C-DTBZ). METHODS: (11)C-HED and (11)C-DTBZ scans were obtained for patients with IPD (n = 9), MSA (n = 10), and PSP (n = 8) and for age-matched control subjects (n = 10). Global and regional measurements of (11)C-HED retention were obtained to assess the extent of cardiac sympathetic denervation. (11)C-DTBZ binding was measured in the caudate nucleus, anterior putamen, and posterior putamen. RESULTS: As expected, extensive cardiac denervation was observed in several of the patients with IPD. However, substantial cardiac denervation was also seen in some patients with MSA and PSP. (11)C-DTBZ studies demonstrated striatal denervation in all patients with IPD and in most patients with MSA and PSP. No correlation was found between cardiac (11)C-HED retention and striatal (11)C-DTBZ binding. CONCLUSION: Cardiac sympathetic denervation was found to occur not only in IPD but also in other movement disorders, such as MSA and PSP. This finding implies that scintigraphic detection of cardiac sympathetic denervation cannot be used independently to discriminate IPD from other movement disorders, such as MSA and PSP. Cardiac sympathetic denervation was not correlated with striatal denervation, suggesting that the pathophysiologic processes underlying cardiac denervation and striatal denervation occur independently in patients with parkinsonian syndromes. These findings provide novel information about central and peripheral denervation in patients with neurodegenerative disorders. 相似文献
72.
听力对语言影响的表现与矫正 总被引:1,自引:1,他引:0
郭金美 《中国听力语言康复科学杂志》2005,(2):42-44
目的 通过对302例药物致聋聋儿的临床观察,研究听力对语言影响的表现,从中摸索积极的矫正补偿方法,使聋儿能听会说,早日回归主流社会。方法:根据听力损失以1/2增益法,选择不同型号的助听器,用具有频率特性的玩具进行适应性训练,采用视觉强化测听法和言语测听法,调整助听器增益,努力使各频率尽可能进入言语香蕉图。结果 100%聋儿表现听觉的敏感性和言语的清晰度低,且存在不同程度的“重振”;聋儿助听补偿效果越好,语言清晰度越高;聋儿只能在信噪比>10 dB SPL的情况下才能听懂语言;言语识别中存在有不同种类的掩蔽现象;双耳配戴助听器对言语接受阈能提高约15%左右。结论:双耳配戴助听器以及利用助听器的微调和耳模的声学作用来改变助听器的频响,选择电脑编程、全数字、带有“AGC”功能、带有指向性麦克风等不同功能的助听器,都是十分有效的矫正措施;选择信噪比≥10 dB SPL的学习环境;充分利用视觉、触觉功能补偿作用;努力学习好辅音;教师正确控制语音、语速、声调、掌握抑扬顿挫,防止声音向上、向后、向前掩蔽。 相似文献
73.
74.
Delta hepatitis virus infection in China 总被引:1,自引:0,他引:1
D Q Wang H H Cheng G Y Minuk L H Liu C M Anand T C Stowe H X Wang D C Ying Y R Tu K A Buchan 《International journal of epidemiology》1987,16(1):79-83
To assess the prevalence, epidemiological features and prognostic implications of hepatitis D (Delta) in Sichuan Province, The People's Republic of China, 649 sera (515 from HBsAg positive patients and 134 from HBsAg negative subjects) were tested by radioimmunoassay (RIA) for antibody to the hepatitis D virus (anti-HD). Forty-seven sera (7.2%) showed some degree of reactivity. Serial dilutions of these sera indicated that prozoning was not responsible for the equivocal results. Thirty-four of the 47 sera were submitted under code to a second laboratory for independent analysis. According to those results anti-HD antibodies were detected in four of these sera. The overall prevalence of anti-HD in the HBsAg positive patients therefore was 0.8% (4/515). On the basis of clinical, biochemical and histological data 427 HBsAg positive sera were further divided into acute Type B hepatitis, chronic Type B hepatitis, healthy carrier state and hepatocellular carcinoma (HCC) subgroups. Two of 65 (3.1%) anti-HD positive sera belonged to the acute Type B hepatitis group; one of 104 (0.9%), the chronic Type B hepatitis group and one of 246 (0.4%), the healthy carrier group. No antibody was detected in sera from 12 HBsAg positive HCC patients. All HBsAg negative patients were negative for anti-HD antibody. The results of this study indicate that despite a high prevalence of hepatitis B virus infection, positive serology for delta virus is uncommon in Sichuan Province, The People's Republic of China. 相似文献
75.
76.
目的 初步建立阴道粘膜上皮细胞体外培养方法,为阴道粘膜上皮研究提供实验模型.方法 取雌性新西兰大白兔阴道粘膜组织小块,胶原酶Ⅳ和胰蛋白酶联合消化分离法收集上皮细胞,接种于角朊细胞无血清培养液中静置培养、传代.动态观察细胞生长增殖情况,扫描和透射电镜观察超微结构,流式细胞仪测定细胞增殖周期,并进行免疫组织化学鉴定.结果 体外培养的阴道粘膜上皮细胞为二倍体细胞,增殖状态良好,细胞间可见桥粒连接,免疫组化角蛋白染色阳性.细胞的超微结构和免疫组化染色均具有上皮细胞特征.结论 在本实验条件下,体外培养的阴道粘膜上皮细胞具有较好的增殖能力,可作为阴道粘膜上皮研究的理想实验模型. 相似文献
77.
78.
79.
目的:建立乳腺非典型增生病动物模型,探讨非典型增生与血管生成的关系。方法:采用灌服二甲基苯蒽+颈部枷具方法复制大鼠肝郁血瘀型乳腺非典型增生动物模型,并给予中药乳复汤治疗。常规染色观察大鼠乳腺组织病理组织形态.免疫组化方法检测MVD、VEGF和bFGF的表达。结果:病证模型组乳腺非典型增生率90%.较单纯造模组高.P=0.0415;中药乳复汤治疗组非典型增生率较病证模型组低.P=0.0459;随着一般增生到非典型增生程度加重,MVD计数增多,VEGF、bFGF的表达升高,P〈0.05。结论:病证结合造模更适合中医动物实验要求,中药乳复汤具有抑制血管生成作用。 相似文献
80.
The authors reviewed the radiographic manifestations of 17 cases of parosteal osteosarcoma, with pathologic correlation in 15. There were two types of parosteal osteosarcoma radiologically. The majority of cases were type I with uniformly dense masses which had regular borders. They often adhered to the cortex and showed no evidence of soft-tissue invasion which correlated with low-grade pathologic malignancy and a relatively benign clinical course. Type II involved the bone, soft-tissue and the medullary cavity. These lesions were poorly differentiated and frequently accompanied by metastatic lesions.
相似文献