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61.
62.
Objective The purpose of this study is to analyze clinical aspects and disease-free survival (DFS) in children less than 3 years of age diagnosed with low-grade astrocytoma. Methods In a period of 24 years (1980–2004), a total of 43 (5.4%) children were registered with these characteristics. Twenty-three patients had pilocytic astrocytoma, 18 diffused, and 2 mixed. Thirty-one (72.1%) children had incomplete surgical tumor resection and 12 (27.9%) had a complete tumor resection. Twelve (27.9%) patients had cranial radiotherapy and 17 (39.5%) received chemotherapy. Overall survival was recorded in 23 (53%). DFS was 50% at 250 months of follow-up for the whole group. DFS for the supratentorial group was 60% at 250 months, whereas, for the infratentorial, it was 22% at 120 months (p = 0.008). Conclusion The only favorable prognostic pattern was the supratentorial presentation. Radiotherapy and chemotherapy did not alter the outcome.  相似文献   
63.
中药安迪对HL-60细胞分化的诱导作用   总被引:4,自引:1,他引:3  
目的 探讨安迪粉针剂 (Andi)对 HL- 60细胞分化的诱导作用 .方法 采用人早幼粒白血病细胞株 (HL - 60 )为靶细胞 ,分为不加任何药物的对照组 (C组 )、安迪粉针剂 (Andi)组、阳性对照药维甲酸 (RA)组和苦参 (KS)组 ,进行体外培养和诱导分化 ,观测细胞生长曲线、细胞形态、硝基蓝四氮唑(NBT)还原和吞噬能力等指标 .结果  2 mg· L-1 Andi可显著地抑制 HL - 60细胞增殖 ,使原始细胞分化为中幼以下的成熟细胞 ,分化后的细胞具有 NBT还原能力和吞噬功能 ;Andi为 68.0 % ,RA为 61 .5% ,KS为 59.0 % ,C组还原能力仅6.0 % (P<0 .0 1 vs C) .其形态的改变和吞噬能力与阳性对照药维甲酸 (RA)和苦参 (KS)相似 ,分别为 52 .0 % ,45.5%和56.5% (P>0 .0 5) ;均明显高于空白对照组 .C组吞噬功能仅7.5% (P <0 .0 1 vs C)其 NBT还原能力与 KS相当 (P >0 .0 5) .结论  Andi对 HL - 60细胞具有显著的诱导分化作用  相似文献   
64.
The objectives have been to establish evidence-based guidelines and identify controversies regarding the management of patients with brain metastases. The collection of scientific data was obtained by consulting the Cochrane Library, bibliographic databases, overview papers and previous guidelines from scientific societies and organizations. A tissue diagnosis is necessary when the primary tumor is unknown or the aspect on computed tomography/magnetic resonance imaging is atypical. Dexamethasone is the corticosteroid of choice for cerebral edema. Anticonvulsants should not be prescribed prophylactically. Surgery should be considered in patients with up to three brain metastases, being effective in prolonging survival when the systemic disease is absent/controlled and the performance status is high. Stereotactic radiosurgery should be considered in patients with metastases of 3–3.5 cm of maximum diameter. Whole-brain radiotherapy (WBRT) after surgery or radiosurgery is debated: in case of absent/controlled systemic cancer and Karnofsky Performance score of 70 or more, one can either withhold initial WBRT or deliver early WBRT with conventional fractionation to avoid late neurotoxicity. WBRT alone is the treatment of choice for patients with single or multiple brain metastases not amenable to surgery or radiosurgery. Chemotherapy may be the initial treatment for patients with brain metastases from chemosensitive tumors.  相似文献   
65.
Within vivo 1H-MRS resonances of several metabolites were simultaneously measured in cerebral gliomas and adjacent normal brain. 15 patients with inoperable brain gliomas all histologically verified were monitored with 1H-MRS and MRI before and after radiotherapy. 11 patients were evaluable. 1H-MRS technique evolved from single volume measurements to one dimensional and two dimensional 1H spectroscopic imaging. In all patients N-acetyl-aspartate signals were decreased in tumour areas compared to the normal brain hemisphere. No recovery was seen after radiotherapy. Choline signals were increased in tumour margins of high grade gliomas and more diffusely in low grade gliomas. In 5 patients the choline resonance decreased after radiotherapy, accompanied by a shrinkage of tumour diameter on MRI. Lactate signals were present in high grade and unspecified astrocytomas and absent in most low grade gliomas. In 3 patients the lactate signal disappeared after radiotherapy. These observations indicate the feasibility of 1H-MRS in monitoring metabolic responses on radiotherapy of brain gliomas.  相似文献   
66.
67.
目的:分析立体定向X-刀放射治疗颅内肿瘤后的近期疗效,并进行阶段性工作总结。材料和方法:53例不同类型脑瘤患者,以CT、MR、DSA图像资料作为定位依据,用德国Brain LAB治疗计划系统设计三维优化方案,西门子MD-2型直线加速器旋转照射。结果:53例患者经X-刀治疗后,近期均取得了满意效果,诸如以卡氏评分法评价,临床症状有所改善;以CT增强扫描复查观察,肿瘤大小趋于缩小或消失。结论:立体定向放射治疗后的追踪观察表明,只要严格掌握适应症,精确定位,精确计划,精心治疗,X-刀是一种安全、有效、无痛苦的治疗脑肿瘤的方法。它可起到改善临床症状,提高患者生活质量,延长生存期限的作用。  相似文献   
68.
Tumour uptake of 11C-thymidine labeled in the methyl position was assessed after intravenous injection in 13 patients with head and neck tumours. This activity was compared to other tracers such as C15O, 13NH3 and C15O2. In every single case a 'positive' tumour image after injection of 11C-thymidine was obtained. Time-activity curves showed the initial activity to be followed by a rapid decrease over the first 10-15 min with an apparent plateau thereafter. A similar level of uptake was found in normal salivary gland regions and myocardium, while higher activities were noted in liver and kidney parenchyma. It is suggested that both blood flow and cellular metabolism can influence 11C-thymidine imaging in this class of human tumours.  相似文献   
69.
Case report 720     
A man presented with a mass in the left first metacarpal bone. Later, his chest radiograph showed extensive, bilateral, rounded opacities in both lungs with enlarged hilar lymph nodes, and he developed expanding lesions in the left radius, ulna, and metacarpal bones. The pulmonary lesions were treated with radiotherapy and cytotoxic agents, and the tumor mass in the first metacarpal was debulked. All biopsies showed similar features of a mixed tumor (pleomorphic adenoma) with metastatic or embolic pulmonary involvement; ultrastructural and immunocytochemical investigations supported this unique diagnosis. The patient remains well 15 years after the initial diagnosis. It is possible that the myoepithelial elements in this case had been displaced intraosseously during development. We are not aware of a similar case in the literature.  相似文献   
70.
Nuclear Medicine offers screening methods for oncology such as bone and bone marrow scintigraphy. During the last two decades, special procedures have gained widespread application. This paper is centered around the “tumor-specific” radiopharmaceuticals. In patients with thyroid cancer, I-131 still plays a significant role. Ga-67 still has its indications in lymphoma, while in other diseases Tl-201 cloride is now the agent of choice. Especially in thyroid cancer, Tl-201 has proved to be a reliable tumor imaging radiopharmaceutical. More recently, Tc-99m MIBI was introduced for tumor imaging. Tc-99m HMPAO may also be used for tumor scintigraphy, especially in brain lesions. In addition, I-123 IMP has successfully been used for imaging malignant melanoma. Another promising field of tumor diagnosis is receptor imaging. In neuroblastoma and malignant pheochromocytoma, I-131/123 mIBG is the radiopharmaceutical of choice and may be considered as a receptor imaging agent also. First clinical results with In-111 octreotide show potentials as somatostatine-receptor radiopharmaceutical in insulinoma, islet cell carcinoma, medullary and lung cancer, while I-123 estradiol needs some improvement until it may be recommended as diagnostic tool in breast cancer. Since 1978, radiolabeled poly- or monoclonal tumor antibodies and their fragments have gained widespread application. Especially the Tc-99m 225.28S melanoma antibody, I-131 or Tc-99m CEA and In-111/I-131 labeled OC-125 antibodies have proven to be of clinical significance in melanoma, colorectal and ovarian cancer.  相似文献   
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