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排序方式: 共有523条查询结果,搜索用时 15 毫秒
71.
关于膳食纤维抗大肠癌的研究   总被引:5,自引:0,他引:5  
科学家和医生们对食物纤维与结肠癌风险之间的关系,已进行了20多年的研究,取得了许多研究成果,但也存在着一些争论。本文介绍了国外对此问题的研究方向、研究方法及其进展情况。  相似文献   
72.
Serum samples from endometrial cancer (EC) patients and healthy females were analyzed using surface-enhanced laser desorption-ionization time-of-flight mass spectrometry (SELDI-TOF-MS) to discover the potential diagnostic biomarker for detection of EC. A preliminary training set of spectra derived from 40 EC patients and 30 healthy women were used to develop a proteomic model that effectively discriminated cancer patients from healthy women. The training set had a specificity of 100% and sensitivity of 92.5% in the EC detection. A blind test set, including 20 new cancer cases and 10 healthy women, was used to validate the sensitivity and specificity of this multivariate model, which had a corresponding results of 60% in specificity and 75% in sensitivity, respectively. The combination of SELDI-TOF-MS with bioinformatics tools could help find new biomarkers and establish the detection of EC with high sensitivity and specificity.  相似文献   
73.
费歇判别法在乳房癌诊断中的应用   总被引:3,自引:0,他引:3  
研究了乳房肿瘤的分类问题,通过对500个已知肿瘤性质(良性或恶性)细胞核的显微图像的10个量化特征进行统计分析,利用费歇判别法,建立了费歇判别模型,给出了判别准则,对未知乳房肿瘤性质的病例进行了成功的诊断;最后对变量进行了合理的缩减.本方法具有良好的实用性和操作性.  相似文献   
74.
    
Circulating levels of gonadotropins (FSH,LH), prolactin (PRL), estradiol and progesterone were measured by radioimmunoassay in the sera of 60 patients with histopathologically proven breast cancer. 30 patients belonged to the post and 30 to the premenopausal group. 30 healthy women, 15 each in the pre and post menopausal groups served as controls for the study. Prolactin was elevated in 33% and 26% of pre and post menopausal breast cancer patients respectively. Lower levels of estradiol and progesterone were observed during the luteal phase of the menstrual cycle in premenopausal breast cancer patients. Among postmenopausal patients with breast cancer, LH was elevated in 32%, FSH in 15% and estradiol in 30% of the patients studied.  相似文献   
75.
Deficiency or excess of certain trace elements has been considered as risk factor for prostate cancer. This study was aimed to detect differential changes and mutual correlations of selected trace elements in prostate cancer tissue versus benign prostatic hyperplasia tissue. Zinc, copper, iron, calcium and selenium were analysed in histologically proven 15 prostate cancer tissues and 15 benign prostatic hyperplasia tissues using atomic absorption spectrophotometer. Unpaired two tailed t test/Mann–Whitney U test and Pearson correlation coefficient were used to compare the level of trace elements, elemental ratios and their interrelations. As compared to benign prostatic tissue, malignant prostatic tissue had significantly lower selenium (p = 0.038) and zinc (p = 0.043) concentrations, a lower zinc/iron ratio (p = 0.04) and positive correlation of selenium with zinc (r = 0.71, p = 0.02) and iron (r = 0.76, p = 0.009). Considerably divergent interrelationship of elements and elemental ratios in prostate cancer versus benign prostatic hyperplasia was noted. Understanding of differential elemental changes and their interdependence may be useful in defining the complex metabolic alterations in prostate carcinogenesis with potential for development of element based newer diagnostic, preventive and therapeutic strategies. Further studies may be needed to elucidate this complex relationship between trace elements and prostate carcinogenesis.  相似文献   
76.
目的:探讨大肠癌、乳腺癌中生存素的临床意义。方法:收集大肠癌68例,乳腺癌69例,利用SABC免疫组织化学方法,检测Survivin表达状况。结果:大肠癌和乳腺癌中Survivin阳性率分别为63.24%和42.03%,Survivin在大肠癌低分化组和深浸润组阳性率明显高于浅浸润和高分化组;在浸润型乳腺癌组和有淋巴结转移组Survivin阳性率明显增高。结论:Survivin表达与癌组织生物学特性有关;检测癌组织中Sur-vivin表达可以提示预后及指导靶向治疗方案的制定。  相似文献   
77.
Distribution of H.pylori antigens in gastric mucosa and its significance   总被引:2,自引:0,他引:2  
INTRODUCTION Helicobacter pylori (H.pylori) was grouped as a class I carcinogen by the International Agency for Research on Cancer in 1994. A direct relation be-tween H.pylori infection and gastric carcinogenesis was demonstrated in 1998 in an experimental animal model (Watanabe et al., 1998). However, the role of H.pylori in human gastric carcinogenesis is sup-ported almost exclusively by epidemiological data and prospective histopathological studies. So far the mechanism of H.pylor…  相似文献   
78.
    
HER-2 is overexpressed in approximately 20–30% of invasive Breast Cancer. ECD of the HER-2 protein is frequently cleaved and released into the circulation, where it can be detected by ELISA in up to 45% of patients with metastatic breast cancer. The objective of our study was to compare the current methods for the detection of HER-2 protein. Tissue HER-2 levels were studied in 100 breast cancer patients by IHC and compared with serum HER-2 levels by ELISA. IHC frequency was 29%. Serum HER-2 ECD was positive in 42% of patients. A statistically significant correlation was observed. HER-2 detected by IHC correlates significantly with serum HER-2 levels detected by ELISA. Thus, ELISA is a reliable and economical tool to assess the HER-2 status in tumors, when breast tissue sample is not available.  相似文献   
79.
抗肿瘤纳米中药制剂研究   总被引:1,自引:0,他引:1  
纳米中药作为中药的新剂型,具有缓释、靶向性等特点,能够降低中药的毒副作用,提高中药的治疗效果,同时对许多肿瘤的治疗显示了良好的抑制效应。拟对紫杉醇冻干纳米乳的制备及理化性质、羟基喜树碱纳米乳的制备及其抗癌作用做初步研究。  相似文献   
80.
目的实验以非小细胞肺癌H1299细胞(简称H1299细胞)为研究对象,主要探讨白藜芦醇联合野生型p53质粒对H1299细胞凋亡作用的影响以及进一步探讨其作用机制。方法在H1299细胞中导入野生型p53质粒,加入不同浓度的白藜芦醇,通过MTT法确定白藜芦醇联合野生型p53质粒的最佳作用浓度,并检测白藜芦醇联合野生型p53质粒对细胞增殖的影响;光镜下观察细胞形态学的变化;流式细胞术检测白藜芦醇联合野生型p53质粒对H1299细胞凋亡率的影响;RT-PCR实验方法检测细胞凋亡相关基因Bcl-2、Bax、Caspase3、Caspase9的表达水平。结果白藜芦醇联合野生型p53质粒能明显抑制H1299细胞的增殖,诱导H1299细胞凋亡,明显抑制Bcl-2基因的表达水平,促进Bax、caspase3、caspase9基因的表达水平。结论白藜芦醇联合野生型p53质粒能够明显抑制H1299细胞的增殖,可能通过促凋亡基因Bax、凋亡蛋白酶Caspase3,Cas?pase9的表达,抑制抑凋亡基因Bcl-2的表达,从而激活细胞中线粒体介导的凋亡通路,诱导H1299细胞凋亡。  相似文献   
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