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51.
成人颅内原始神经外胚层肿瘤的MRI表现和病理对照   总被引:16,自引:0,他引:16  
目的 探讨成人颅内原始神经外胚层肿瘤(primitive neuroectoderrnal tumors,PNET)的MRI特征,以期提高对该病的认识。方法回顾性分析了7例经手术和病理证实的成人颅内PNET的MRI表现,并与手术、病理相对照。结果 肿瘤多位于大脑半球和小脑蚓部,浸润性生长,瘤组织由低分化的小细胞构成,形态上可向多种细胞过渡。(2)MRI上肿瘤较大,4例呈浅分叶状,边界较清楚,瘤周水肿轻微;平扫呈不均匀较低T1、等或高T2信号,内部常伴有囊变和坏死区、可有出血和钙化;增强扫描6例肿瘤有明显的不均一强化;2例发生颅内转移,1例术后发生腰椎转移。结论 成人颅内PNET的MRI表现有一定特点;MRI有助于该病的诊断和指导治疗。  相似文献   
52.
Ten patients suffering from intramedullary pilocytic astrocytomas (WHO-classification: astrocytoma grade I) were investigated catamnesticly. Combined surgery and radiotherapy was performed. Seven patients received neutron irradiation postoperatively. In four cases the neurological symptoms were improved after follow-up periods ranging from 33 to 89 months. The three other patients died after 6 to 21 months. The autopsy findings of a 14 year old child are presented. Our results are compared with reports in the literature. In addition, long-term problems of the spinal column are discussed. It seems that the combined surgical and neutron therapy improves the prognosis of pencil gliomas.  相似文献   
53.
本文报道脑瘤病人胸腺移植前后细胞免疫和体液免疫的几项常规指标。所有接受移植的患者均未出现任何免疫排斥反应或移植物抗宿主反应。将病人随机分为两组,一组经穿刺移植;一组以手术植入。两组患者移植前、后测定淋巴细胞数、淋巴细胞转化率及 E-玫瑰花环形成率均呈现极显著性差异(P<0.001)。血清中 IgG 和 C_3也呈现显著差异(P<0.05)。  相似文献   
54.
不同地区冬凌草有效成分抗肿瘤作用研究   总被引:1,自引:0,他引:1  
卢氏1号及信阳A,B都是从冬凌草[Rabdosia rubescens(Hemsi)]中提取出来的,均为新的二萜类抗肿瘤成分,实验证明:这三种成分对体外培养的艾氏腹水癌细胞具有较明显的细胞毒作用。对动物移植性肿瘤ECA,ARS,S_(180),HCA,HCS,P_(388),L_(1210),LLC及B_(16)均有较强的抗肿瘤作用(P<0.05)。对小鼠体液免疫(溶皿素方法),及细胞免疫(肿瘤相伴免疫方法)均无明显影响。急性毒性LD_(50)卢氏1号为69.5±6.7mg/kg,信阳冬凌草水剂为10.6±0.9g/kgip。  相似文献   
55.
 Infantile myofibromatosis is a mesenchymal tumor most commonly seen in infancy. The tumors have a variable appearance on CT/MR and often simulate a more aggressive neoplasm. This report describes CT/MR findings in cases of infantile myofibromatosis with pathologic correlation. Discussion into the success of imaging in suggesting the correct diagnosis is also addressed. Infantile myofibromatosis is a mesenchymal disorder of infancy characterized by the presence of tumorous nodules in the skin, subcutaneous tissue, muscle, viscera, and bone. Cases of solitary and multiple lesions have been described. We present the clinical, histologic, and radiographic findings of one case of the solitary form of infantile myofibromatosis that was recently diagnosed at our hospital.  相似文献   
56.
The diagnostic yield of cytology in histologically proven transitional-cell carcinoma (TCC) of the urinary bladder has been studied in 100 cases. Cytohistologic correlation rates were 20 percent, 61.7 percent, and 92.8 percent, respectively, for grade 1, 2, and 3 tumors. When further evaluated, G2 cases were segregated into 2 subcategories, G2a and G2b, based on histologic preservation of nuclear polarity, pleomorphism, and other cellular irregularities. Correlation rates were rather low for G2a cases (6/18, 33%) and high for G2b cases, (23/29; 79%). The prevalence of atypical cells was 2 (11.1%) cases in G2a and 16 (55.2%) cases in G2b. The results of this study confirm that cytology has an extremely varying diagnostic yield in urinary bladder TCC. Greater cell exfoliation, increased atypia, and a tendency to infiltration of G2b and G3 cases probably account for the higher diagnostic yield detected in these groups.  相似文献   
57.
This experiment was designed to examine the effects of indomethacin, a potent prostaglandin synthesis inhibitor, on spontaneous mammary tumors in mice. The growth of established mammary tumors and the appearance of new tumors in multiparous SHN mice were significantly suppressed by the subcutaneous implantation of pellets of indomethacin diluted to 1/12 with cholesterol. Furthermore, the same treatment inhibited normal and preneoplastic mammary gland growth in virgin SHN mice. The pattern of estrous cycles, ovarian structure, and plasma prolactin levels were not affected significantly by the treatment. All results have demonstrated that indomethacin inhibits mammary tumorigenesis of mice primarily by route(s) other than the endocrine system under the present experimental conditions. Indomethacin would be the first agent that appears to inhibit the growth of spontaneous mammary tumors of palpable size in mice.  相似文献   
58.
BACKGROUND: Although it has been reported that ghost cells are present in odontomas, the generation mechanism of these cells is unclear. To evaluate the presence of ghost cells and involvement of the Wnt signaling pathway, we examined the expression of hard keratins, beta-catenin and Lef-1 in odontomas. METHODS: Sixty-nine cases of odontoma were examined immunohistochemically with the use of antibodies against human hair proteins, beta-catenin and Lef-1. RESULTS: Expression of hard keratins was found only in the cytoplasm of ghost cells in 46 (66.7%) of the 69 odontomas. Compound odontomas (78.8%) showed a higher incidence of ghost cells than complex odontomas (29.4%). Histopathologically, ghost cells were found within odontogenic epithelium adjacent to immature enamel and in the centre of Liesegang-ring-like calcified materials. Expression of beta-catenin and Lef-1 was observed in the cytoplasm and nucleus of odontogenic epithelial cells adjacent to the ghost cells in immature odontomas. CONCLUSION: These findings suggest that odontoma is a hard keratin-expressing tumor-like lesion, and that the Wnt signaling pathway may be involved in the formation of ghost cells in odontomas.  相似文献   
59.
目的:提高对小儿早期睾丸卵黄囊瘤的诊断与治疗水平。方法:回顾性分析12例小儿早期睾丸卵黄囊瘤的病例资料。结果:12例患者术前行阴囊B超示睾丸增大,内部回声不均匀,7例可见睾丸内积液改变;甲胎蛋白(AFP)值均明显升高。12例均行根治性睾丸切除术,术后行病理检查确诊。术前、术后均未行化疗,9例随诊5年未见复发,2002年就诊的3例目前未见复发症状。结论:小儿早期睾丸卵黄囊瘤可根据相关检查结果,结合病理检查确诊。治疗方法为行根治性睾丸切除,可不作化疗,预后较好。  相似文献   
60.
18F-FDG PET鉴别肾上腺良恶性肿瘤的临床价值   总被引:3,自引:0,他引:3  
目的:评价^18F-氟代脱氧葡萄糖正电子发射计算机断层显像(^18F-FDG PET)在肾上腺病变定性诊断中的应用价值。方法:回顾性分析22例28个肾上腺肿瘤患者的临床资料,均采用^18F-FDG PET显像,以鉴别肾上腺肿瘤为原发性抑或继发性,同期均行CT检查。结果:CT检查28个肿瘤中22个为恶性肿瘤(其中6个经手术或活检证实,16个随访证实),6个通过活检或随访证实为良性病变。CT发现的19个肾上腺肿瘤中。17个为恶性肿瘤,^18F—FDG PET显像均为阳性。^18F—FDG PET对肾上腺肿瘤的定性判断的灵敏度、特异度和准确度分别为100%、66.7%和92.9%。结论:^18F—FDG PET通过肿瘤的葡萄糖代谢程度来判定病变的性质,对肾上腺恶性病变的标准摄取率(SUV)相对较高,在肾上腺肿瘤良恶性鉴别中可以提供重要的依据。  相似文献   
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