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61.
运用时窗复杂度序列来分析睡眠脑电,减少了非平稳性及状态空间的不均匀性造成的脑状态信息的丢失,在一定程度上克服了复杂度自身的局限,有助于不同睡眠期状态特征的提取。另外采用独立分量分析(ICA),小波变换等方法对脑电进行预处理,实验表明它们能有效地去除脑电中的一些生理干扰,有利于提高复杂度算法在睡眠分期应用中的精确度。 相似文献
62.
R. Yoshiyuki Osamura Keiichi Watanabe Nabil G. Seidah John S. D. Chan Michel Chrétien 《Virchows Archiv : an international journal of pathology》1985,408(2-3):281-287
Summary Immunohistochemical localization of theN-terminal fragment (1–76) (NTF) of human pro-opiomelanocortin (POMC) was studied in human adult and fetal pituitary glands, as well as in pituitary adenomas associated with Cushing's syndrome and in ectopic ACTH-producing tumors. Comparison of localization between NTF and ACTH was performed using mirror sections. Our results indicated concomitant localization of NTF and ACTH in the same cells, not only in normal adult and fetal pituitaries but also in pituitary adenomas and ectopic ACTH producing tumours. Specificity of the NTF staining was confirmed by immunoabsorption. Negative staining of the bovine pituitary gland indicated the immunohistochemical localization ofN-terminal (1–45) of human POMC as there is a known species difference in the sequence 1–45 between human and the bovineN-terminal fragment. Presence of NTF in cisterna of rough endoplasmic reticulum indicates its production by small cell carcinoma. These findings, together with the previous studies, suggest that the complete form of POMC is produced in the tumours as well as in normal pituitaries.This work was supported in part by the Grant-in-Aid for Cancer Research (58-Z) from the Ministry of Health and Welfare.Supported by NIH # 16315-04 and by a program grant from the Medical Research Center of Canada 相似文献
63.
HCCA1在原发性肝癌中的表达及其意义 总被引:1,自引:0,他引:1
目的 对近期克隆的新基因HCCA1与肝癌的相关性进行研究。方法 采用Northern杂交分析HCCA1 mRNA在肝癌中的表达,应用制备的特异性抗体检测其蛋白水平的表达,结合临床及病理学资料进行分析。结果 65例HCC患者在其癌组织中HCCA1 mRNA表达的检出率为90.8%(59/65),其中91.5%(54/59)患者HCCA1 mRNA在肝癌组织中的表达水平明显高于癌旁组织,有13.8%(9/65)患者在癌旁组织中检测到较弱的HCCA1 mRNA的表达,86.2%(56/65)患者在癌旁组织中未检测到HCCA1 mRNA的,与病理指标的相关性分析表明,HCCA1 mRNA在Ⅲ-Ⅳ级肝癌中的表达水平明显高于Ⅰ-Ⅱ级肝癌,有门脉癌栓形成者的表达水平明显高于无癌栓形成者。免疫组织化学在蛋白水平上证实HCCA1在肝癌中的高表达。结论 HCCA1是一个新的肝癌相关基因,可能在肝癌的浸润和转移中起重要作用。 相似文献
64.
鼻咽癌放疗后局部复发和纤维化的增强CT鉴别诊断价值 总被引:16,自引:0,他引:16
目的探讨鼻咽癌放疗后出现块影时,CT检查对鉴别肿瘤局部复发和放射性纤维化的价值。方法收集159例经CT检查的鼻咽癌,其中放疗后局部复发(RT)37例,放射性纤维化(RF)54例,以68例未经放疗的鼻咽癌(PT)作对比。使用ELScintsprint2000型CT机,测量放疗后出现的块影平扫和强化的CT值,用统计学的方差分析法处理增强前后的CT值差异。结果RT组平扫CT值为50.40±8.10Hu,增强为73.74±7.37Hu;RF组平扫为48.62±10.15Hu,增强为56.74±8.69Hu;对照组(PT)病变区平扫为48.32±9.20Hu,增强为72.38±7.75Hu。测量表明RT组有明显强化,RT组与RF组强化后CT值差异有非常显著性(P<0.01)。结论鼻咽癌放疗后出现块影时,CT增强扫描可作为鉴别诊断的重要方法。 相似文献
65.
Videosurgery in oncological pediatrics 总被引:2,自引:0,他引:2
J. M. Guys A. Delarue H. Le Hors-Albouze C. Esposito C. Louis-Borrione M. Portas P. Gentet 《Pediatric surgery international》1995,10(5-6):371-373
As a recent innovation, videosurgery (VS) has enjoyed rapid and widespread development. While colon cancers in adults are quite commonly removed using laparoscopic techniques, children could also benefit from the improved diagnostic and interventional possibilities using VS techniques. From January 1992 to February 1994, we carried out 15 procedures. Eight thoracic operations were performed on 7 patients: diagnostic in 5 cases and metastasis resection in 3. Six patients underwent 7 laparoscopic operations for biopsies (5) or lymph-node harvesting (2). Based on this experience, we discuss the advantages of VS (noninvasive technique for primary or second-look exploration, guided biopsies, and removal of tumors) and its risks (spillage of malignant cells, subjective palpation) in the management of pediatric malignancies. 相似文献
66.
目的 减轻胰腺转移癌病人的疼痛,提高病人晚期的生活质量。方法 对28 例胰腺转移癌癌性疼痛病人在 B 超和( 或) C T 扫描定位下,采用60 Co 分次外照射,总剂量为30 ~40 Gy 。结果 28例中、重度癌性疼痛病人的镇痛有效率达92 .9 % ,显效率为88 % 。结论 60 Co 外照射治疗胰腺转移癌,方法简便,病人痛苦小,止痛效果确切,但存有不能立即止痛,需配合其它止痛药之缺点。 相似文献
67.
68.
恶性肿瘤体内外生长和发展过程与细胞外基质相关性的研究 总被引:12,自引:0,他引:12
目的探讨细胞外基质在肿瘤侵袭转移中的作用。方法利用小鼠肺腺癌细胞母系LA795移植于T739小鼠皮下和肾包膜下,以及人鼻咽癌细胞系CNE-2Z移植于裸小鼠皮下等体内移植模型,通过间接免疫酶标和间接免疫荧光技术,测定纤维粘连蛋白(FN)、层粘连蛋白(LN)与Ⅳ型胶原(ⅣC)在肿瘤移植后不同时间的表达,并利用多种体外实验方法(琼脂糖滴瘤细胞移动实验、软琼脂上瘤细胞集落生长速度测定、斑点杂交等),分析瘤细胞运动能力、瘤细胞集落生长速度等与LN、FN和ⅣC之间的关系。结果随着肿瘤的生长,FN、LN与ⅣC的表达均增强,且呈不同的分布;外源性FN、LN及ⅣC能提高瘤细胞的体外运动能力和促进瘤细胞集落的体外生长。结论细胞外基质的分布及其合成和降解的变化,与恶性肿瘤的侵袭和转移有关,对预测肿瘤生物学行为有参考价值。观察细胞外基质与瘤细胞侵袭的关系,肾包膜下移植模型较为理想 相似文献
69.
目的:检测垂体腺瘤组织中垂体肿瘤转化基因(PTTG)、bFGF mRNA的表达,分析其与垂体腺瘤侵袭性的关系及临床意义。方法:应用逆转录PCR(RT—PCR)方法检测30例垂体腺瘤组织标本中PTTG、bFGF mRNA的表达,分析二者与垂体腺瘤侵袭性的关系。结果:侵袭性垂体腺瘤组的PTTG、mRNA表达、bFGF mRNA表达均较非侵袭性腺瘤组增高,其差异具有统计学意义。结论:垂体腺瘤侵袭性的发生与垂体肿瘤转化基因(PTTG)表达增高及其上调血管生成正调节因子bFGF并表达、促进血管生成有关, 相似文献
70.
Contribution of PET imaging to the initial staging and prognosis of patients with Hodgkin's disease.
R Munker J Glass L K Griffeth T Sattar R Zamani M Heldmann R Shi D L Lilien 《Annals of oncology》2004,15(11):1699-1704
BACKGROUND: Positron emission tomographic (PET) scanning utilizing [18F]fluorodeoxyglucose (FDG) is a new method of tumor imaging based on the increased glucose metabolic activity of malignant tumors. In Hodgkin's disease (HD), PET has proven value for the evaluation of residual masses following treatment and for the early diagnosis of relapse. In the initial staging of HD, PET frequently shows a higher stage than conventional methods (upstaging by PET). In the present study, we evaluated the frequency of stage changes by PET in a multicenter setting and determined its prognostic relevance. PATIENTS AND METHODS: A total of 73 patients with newly diagnosed HD were staged with both conventional methods and whole-body PET scanning. All histological types and stages were represented. The median time of follow-up after the initial diagnosis was 25 months (range 1 month to 5 years). The response to treatment was determined by standard clinical and diagnostic criteria. For the purpose of this analysis, data from a PET center associated with a university medical center and a PET center associated with a group oncology practice were combined. RESULTS: A total of 21 patients (28.8%) were upstaged by PET compared with conventional methods. In two cases (2.7%), a lower stage was suggested by PET scanning. With one possible exception, the upstaging had no obvious clinical or biological correlate. Among 12 patients in stage I (A + B) by conventional methods, seven were upstaged by PET (58.3%), four to stage II, one to stage III and two to stage IV. Among 42 patients in stage II, eight were upstaged by PET (19.0%), six to stage III and two to stage IV. Among 12 patients in stage III, six (50%) were upstaged to stage IV by PET. If only early-stage patients and major changes are considered (stages IA-IIB to III or IV), among 49, 10 were upstaged to III or IV, whereas in 39 staging was unchanged following PET. In the former group, three relapsed or were refractory compared with none in the latter group (P<0.006). In advanced stage patients (IIIA or IIIB) a trend toward treatment failure was apparent in patients who were upstaged by PET. CONCLUSIONS: PET scanning is an interesting new modality for the accurate staging of patients with HD and frequently shows a higher stage than conventional methods. PET should be performed at initial diagnosis and should be included in prospective studies of patients with HD. Upstaging by PET may represent a risk factor for a more advanced stage or a biologically more aggressive tumor. Patients with early-stage disease as identified by conventional methods have a significant risk of treatment failure if a more advanced stage is indicated by PET. At present, major stage changes suggested by PET imaging should be confirmed by an independent diagnostic method. 相似文献