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41.
A multicenter phase II trial was conducted to define the activity of letrozole in postmenopausal women with recurrent or advanced endometrial carcinoma, who had no more than one prior line of progestins and never had chemotherapy (except adjuvant). Archival paraffin-embedded tumor samples were retrieved to determine the expression level of estrogen (ER) and progesterone receptor (PgR), p53, HER-2, bcl-2 and PTEN protein, and phosphorylation status of protein kinase B (PKB/Akt). Thirty-two eligible patients were treated with letrozole at 2.5 mg daily continuously, of whom 10 (31%) had prior progestins. Of the 28 patients evaluated for response, one complete and two partial responses were noted; overall response was 9.4% (95% confidence interval 2-25%). Eleven patients had stable disease for a median duration of 6.7 months (range 3.7-19.3 months). Amongst 22 patients who had tumor blocks available, the proportion showing positive expression of the following markers includes: PgR (86%), ER (86%), PTEN (82%), phosphorylated PKB/Akt (59%), bcl-2 (45%), p53 (32%), and HER-2 (0%). None of these markers correlated with response to letrozole or disease progression. In conclusion, letrozole is well tolerated but has little overall activity in this cohort of women with endometrial cancer.  相似文献   
42.
A single intramuscular injection of 2 mg estradiol valerate (EV) results in neuronal degeneration and β-endorphin depletion in the hypothalamic arcuate nucleus of adult female rats. We have hypothesized that peroxidase-positive astrocytes in this brain region oxidize estrogens and catecholestrogens to semiquinone radicals which mediate oxidative neuronal injury. In the present study, dietary administration of the potent antioxidant 21-aminosteroid, U-74389F, completely blocked EV-induced β-endorphin depletion in the hypothalami of adult female rats. Neither EV nor 21-aminosteroid treatment had any effect on hypothalamic concentrations of neuropeptide Y and Met-enkephalin, confirming that the estradiol lesion is fairly selective for the β-endorphin cell population. The present findings support the hypothesis that the toxic effect of estradiol on hypothalamic β-endorphin neurons is mediated by free radicals.  相似文献   
43.
Cell culture-based influenza vaccine manufacturing is of growing importance. Depending on virus strains, differences in infection dynamics, virus-induced apoptosis, cell lysis and virus yields are observed. Comparatively little is known concerning details of virus–host cell interaction on a cellular level and virus spreading in a population of cells in bioreactors. In this study, the infection of MDCK cells with different influenza A virus strains in lab-scale microcarrier culture was investigated by flow cytometry. Together with the infection status of cells, virus-induced apoptosis was monitored. A mathematical model has been formulated to describe changes in the concentration of uninfected and infected adherent cells, dynamics of virus particle release (infectious virions, hemagglutinin content), and the time course of the percentage composition of the cell population.  相似文献   
44.
微血管密度和p16基因表达对判定肾癌生物学行为的意义   总被引:1,自引:0,他引:1  
目的 :探讨肿瘤内的微血管密度 (IMD)和 p1 6基因表达与肾细胞癌 (RCC)生物学行为的关系。 方法 :采用免疫组织化学方法 ,对 76例RCC患者的根治性肾切除标本 ,检测第Ⅷ因子相关抗原和 p1 6基因表达 ,分析IMD、p1 6基因表达与RCC分期、分级及预后的相关性。 结果 :IMD随临床分期升高而增加 (P <0 .0 5 ) ,而与分级无明显相关性 (P >0 .0 5 ) ,随访 5年内死亡者IMD明显升高 (P <0 .0 1 ) ;癌旁组织中 p1 6阳性率 (75 .0 % )显著高于RCC组织 (4 8.7% ) ,p1 6阳性表达随临床分期、病理分级升高而降低 (P <0 .0 5 ) ,而与IMD呈负相关性。结论 :IMD是预测RCC恶性行为的一个有用指标 ,IMD和p1 6基因表达可为RCC的疗效和预后判定提供重要的资料。  相似文献   
45.
p21对缺血-再灌注损伤后肾小管上皮细胞演变的影响   总被引:2,自引:0,他引:2  
目的 探讨p21对缺血-再灌注损伤(IRI)后肾小管上皮细胞演变的影响。方法 选择低龄(2个月龄)和高龄(12个月龄)p21(+/+)和p21(-/-)鼠,建立左肾IRI模型。于IRI后0、1、3、7d及1、3、6个月光镜下观察肾小管组织学变化,采用免疫组化法检测肾小管上皮细胞增殖细胞核抗原(PCNA)表达,组织化学染色观察肾小管上皮细胞衰老相关β-半乳糖苷酶(SA-β-gal)活力,末端脱氧核糖转移酶介导的生物素化脱氧尿嘧啶缺刻标记技术(TUNEL)检测肾小管上皮细胞凋亡。结果 IRI后0d,肾小管以坏死为主,高龄鼠比低龄鼠严重、p21(-/-)鼠比p21(+/+)鼠严重(P均〈0.05)。肾小管上皮细胞凋亡在IRI 1d后出现,7d达高峰,且高龄鼠比低龄鼠明显、p21(-/-)鼠比p21(+/+)鼠明显(P均d0.05)。低龄鼠IRI后1个月出现SA—β-gal染色阳性的肾小管上皮细胞,而对侧肾此时未见衰老细胞,3和6个月时衰老的肾小管上皮细胞显著增多,且p21(+/+)鼠比p21(-/-)鼠明显(P〈0.05);p21(+/+)高龄鼠IRI后0d双肾即可见大量的SA-β-gal染色阳性肾小管上皮细胞,且较p21(-/-)鼠显著增多(P〈O.05),但1d后,p21(+/+)和p21(-/-)鼠IRI肾衰老细胞均明显减少(P均〈0.05),1个月后又呈进行性增加,且p21(+/+)鼠始终比p21(-/-)鼠严重。高龄和低龄p21(+/+)鼠PCNA阳性染色细胞出现的几率差异无显著性(P〉0.05),但低龄鼠细胞增殖能力要强于高龄鼠;而p21(-/-)鼠的细胞增殖能力明显强于p21(+/+)鼠,低龄鼠更为显著(P均〈0.05)。对高龄鼠IRI后1d细胞衰老和凋亡进行相关分析显示,二者呈显著负相关Cp21(+/+)鼠:r=-0.82,P〈0.001,p21(-/-)鼠:r=-0.76,P〈0.0013。结论 ①IRI可促进正常肾小管上皮细胞衰老的进程;②已经进入衰老状态的肾小管上皮细胞在遭受IRI刺激后,更易走向死亡[坏死和(或)凋亡];③p21在IRI所致肾小管上皮细胞演变过程中发挥重要的调控作用。  相似文献   
46.
p21-ras、p53和VEGF在甲状腺乳头状癌中的表达及意义   总被引:3,自引:0,他引:3  
目的 研究原癌基因Ras、抑癌基因p5 3及血管内皮生长因子 (VEGF)在甲状腺乳头状癌中的表达及相关性。方法 应用免疫组织化学S P法对 4 0例甲状腺乳头状癌中p2 1 ras、p5 3及VEGF的表达进行研究。结果 甲状腺乳头状癌中存在p2 1 ras、p5 3及VEGF的过度表达 ;VEGF的表达与p2 1 ras、p5 3的表达显著相关 (P <0 .0 5 ) ;VEGF的表达与甲状腺乳头状癌淋巴结转移显著相关 (P <0 .0 5 )。结论 p2 1 ras、p5 3、VEGF在甲状腺乳头状癌的发生发展过程中起重要作用 ;VEGF的表达与p2 1 ras、p5 3表达显著相关 ,可能受其调控。  相似文献   
47.
Objectives: The study was designed to assess the reliability of measurement of 24-hour urinary 17α-hydroxyprogesterone (17-OHP) by radio-immunoassay (RIA) as an alternative biochemical assessment for monitoring the treatment of congenital adrenal hyperplasia (CAH) due to 21 -hydroxylase deficiency (21 -OHD) and to assess the need for sample purification by column chromatography to improve assay specificity.
Methodology: Morning serum 17-OHP was measured using RIA and 24-hour urinary pregnanetriol using gas chromatography. Twenty-four-hour urinary 17-OHP was measured in samples from 17 prepubertal patients with CAH due to 21 -OHD, and 20 normal prepubertal children as controls. In 24 urine samples, RIA of 17-OHP was performed with and without column chromatography.
Results: There was a good correlation between 24-hour urinary 17-OHP and 24-hour urinary pregnanetriol (r = 0.962, P <0.01) and between 24-hour urinary 17-OHP and morning serum 17-OHP ( r = 0.955, P <0.01). There was no significant difference in the RIA of the urine samples with and without purification by column chromatography.
Conclusions: The measurement of 24-hour urinary 17-OHP is a reliable alternative for the biochemical monitoring of 21-OHD, and RIA specificity is unaffected by omission of column chromatography.  相似文献   
48.
人细胞色素p450IA1基因cDNA的克隆和鉴定   总被引:5,自引:1,他引:4  
在用3-甲基胆蒽诱导培养人羊膜FL细胞24h后,抽提细胞总RNA并直接合成cDNA第一链。利用人工合成的一对寡核苷酸引物,采用PCR技术特异性地扩增Cyt p50IA1 cDNA。30个循环后琼脂糖凝胶电泳显示1.5Kb大小片段,长度与预计相符。Southern杂交结果证实此片段确为Cyt p450IA1 cDNA。将此片段克隆至质粒pGEM-3Z并进行部份序列分析。结果显示克隆片段包含Cyt p  相似文献   
49.
The clinical, radiological, and pathological features in 10 cases of ganglioglioma are described. The clinical data were derived from the patients' medical records, including a review of the age, sex, details of the presenting symptoms, radiological imagings, surgical intervention, and the clinical outcome. Age ranged from 1 to 66 years (mean 29); there were five males and five females. The tumors were located in the fronto-medial, bifrontal, temporal, temporo-basal, temporo-parieto-occipital, and parietal lobes; the 3rd ventricle; the cervicothoracic spinal cord; and the conus medullaris. The presenting symptoms were focal seizures, headaches, hemiparesis, paraparesis, and tetraparesis. In four patients, gross total resection was achieved and in the remaining six patients only subtotal resection was possible. Tumor recurrence occurred in three patients, 1 year, 14 months, and 2 years after the first operation. The histopathologic appearance of gangliogliomas showed a broad variation of the neuronal, glial, and stromal component. Studying proliferation characteristics, labeling for Ki-67 ranged from 0 to 13.7% (mean 4.1) and for PCNA from 0 to 32.1% (mean 20.4). Due to their favorable prognosis, early recognition and correct diagnosis are important in order to avoid progressive neurological deficits and unnecessary aggressive therapy. The application of immunohistochemistry for both neuronal (synaptophysin, NSE, NFP) and astrocytic (GFAP) cell markers, as well as proliferation markers, are recommended in the diagnostic setting for gangliogliomas. The treatment of choice is total surgical resection. The role of radio- and chemotherapy is still controversial.  相似文献   
50.
陈书盘  耿沁 《肿瘤》1997,17(5):258-261
目的评价检测CYFRA21┐1对非小细胞肺癌的诊断价值。方法用ELISA法测定70例肺癌(LC)其中47例非小细胞肺癌(NSCLC),3例小细胞肺癌(SCLC)和20例未分型肺癌、64例肺部良性疾病患者及40例健康人血清CYFRA21┐1浓度。试验的诊断性能用相对操作特征(ROC)分析法估测之。结果测得全阈诊断准确率(OveralDiag┐nosticAccuracies)LC为0.75、NSCLC为0.76,SQC为0.83,ADE为0.67和SCLC为0.38。在相应于特异性为0.95的界定值3.47μg/L处,各型的灵敏度分别为SQC0.62,LC0.53,NSCLC0.51,ADE0.48和SCLC0.00。结论结果显示CYFRA21┐1是NSCLC较灵敏和特异的一个标志物。未观察到TNM各期间该标志物的平均水平有明显的差异;然而异常升高水平的患者的比例随病期的进展而显著增加,提示一系列检测CYFRA21┐1水平可能有助于监查NSCLC患者的疗效。  相似文献   
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