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排序方式: 共有399条查询结果,搜索用时 15 毫秒
11.
Wang LR Zhang GB Chen J Li J Li MW Xu N Wang Y Shen Tu JZ 《Journal of Zhejiang University. Science. B》2011,12(3):174-179
Objective
To evaluate the predictive values of gene expressions of ribonucleotide reductase M1 (RRM1) and breast cancer susceptibility gene 1 (BRCA1) in peripheral blood from Chinese patients with non-small-cell lung cancer (NSCLC) treated with gemcitabine plus platinum. 相似文献12.
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
13.
Regi Jose G. R. Sajitha K. T. Augusti 《Indian journal of clinical biochemistry : IJCB》2014,29(2):119-132
Nutraceuticals are nutritional medicines which are present in edible food items. Most of them are antioxidants with various other biological properties viz, anti inflammatory, anti atherogenic, anticancer, anti viral, anti aging properties etc. They are as simple as minerals like Se2+ to complex organic molecules such as glycyrrhizin (Ca2+, K+ salts of glycyrrhizic acid). They can prevent as well as cure various diseases. Most of the medical people are not aware of the importance of the nutraceuticals as such matters are not part of their text books. Many still think that vitamins are the major nutritional medicines. Actually other dietary principles like terpenes, carotenes, phytosterols, polyphenols, flavanoids, di and poly sulphides, their sulfoxides and their precursor amino acids are necessary to scavenge free radicals in the body which are reactive oxygen species to protect and maintain the vitamin levels in the body. They down regulate the activities of those enzymes which are increased in diseases and they increase those that remove oxidants and detoxify carcinogens. They are immune boosters too. Recently glucosinolates, non toxic alkaloids, certain proteins and even fiber are included in the list of nutraceuticals. 相似文献
14.
针对专利技术主题识别方法存在缺少语义语境、可解释性弱和主题界定模糊等问题,提出了一种融合专利结构数据和文本语义的技术主题识别分析方法一并解决上述问题,有助于领域人员把握技术研究内容,为研发决策提供科学支持。方法以专利IPC作为结构数据改进纯文本主题建模获取由IPC和专家分类意见指导的主题词向量,同时使用word2vec获取语义词向量,将结果进行向量拼接,进而获得易于解释的精准技术主题,满足细粒度分析要求。最后,以非小细胞肺癌治疗领域作为实证研究,证实了该方法的科学性和实用性。 相似文献
15.
Amitabha Ray Anil Kumar Bahadur S. L. Dayalu Naik Bhuvnesh Kumar Sharma 《Indian journal of clinical biochemistry : IJCB》2001,16(2):199-202
Endogenous oestrogens are thought to be involved in breast cancer, but few studies could show the direct relationship between
hormones and pathological process of the disease. In the present study, oestradiol was estimated in the serum of pre-and postmenopausal
breast cancer patients along with normal healthy controls and patients with carcinoma of the uterine cervix which is not dependent
on oestrogens. Premenopausal patients with breast cancer showed higher levels of oestradiol as compared to premenopausal control
women as well as cervical cancer patients. Whereas, no statistically significant differences were observed in serum oestradiol
levels amongst postmenopausal groups of breast cancer, cervical cancer and normal women. The result of the study reflects
the association of oestradiol as well as its difference in the pathological events of pre and postmenopausal breast cancer. 相似文献
16.
Bhupendra Pal Singh Shailendra Dwivedi Urmila Dhakad Ramesh Chandra Murthy Vimal Kumar Choubey Apul Goel Satya Narayan Sankhwar 《Indian journal of clinical biochemistry : IJCB》2016,31(1):50-56
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
17.
Dietary restriction (DR) also called dietary control or calorie restriction is reported to have many advantages with regard
to human health. It leads to suppression of obesity, mitigates free radicals and increases available antioxidants which are
accounted for extending the life span of individuals. DR is also reported to induce synthesis of heat shock proteins in animals
as a control mechanism against stress. Further, it is known to play a significant role in decreasing toxicity and lethality
due to a variety of toxic chemicals and drugs by stimulating tissue repair damaged by the toxicants leading to restoration
of intact organ and its functions. Moreover, extensive work done on animals indicate DR has an important role in suppressing
certain types of cancer. In this review an effort is made to highlight the various advantages of DR from the point of human
health perspective. 相似文献
18.
Franky D. Shah Rasheedunnisa Begum Bhairavi N. Vajaria Kinjal R. Patel Jayendra B. Patel Shilin N. Shukla Prabhudas S. Patel 《Indian journal of clinical biochemistry : IJCB》2011,26(4):326-334
Oral cancer has emerged as an alarming public health problem with increasing incidence and mortality rates all over the world.
Therefore, the implementation of newer screening and early detection approaches are of utmost importance which could reduce
the morbidity and mortality associated with this disease. Sensitive and specific biomarkers for oral cancer are likely to
be most effective for screening, diagnosis, staging and follow-up for this dreaded malignancy. Unlike other deep cancers,
oral cancer is located in oral cavity. Hence, the direct contact between saliva and oral cancer lesion makes the measurement
of tumor markers in saliva an attractive alternative to serum and tissue testing. The DNA, RNA and protein molecules derived
from the living cancer cells can be conveniently obtained from saliva. Thus, salivary biomarkers, a non-invasive alternative
to serum and tissue-based biomarkers may be an effective modality for early diagnosis, prognostication and monitoring post
therapy status. In the current post-genomic era, various technologies provide opportunities for high-throughput approaches
to genomics and proteomics; which have been used to evaluate altered expressions of gene and protein targets in saliva of
oral cancer patients. The emerging field of salivary biomarkers has great potentials to prove its clinical significance to
combat oral cancer. Hence, we have reviewed importance of several salivary genomics and proteomics biomarkers for oral cancer. 相似文献
19.
乳腺癌是目前我国发病率较高的癌症类型,直接关系到众多女性的健康.科学预防乳腺癌的发生是控制乳腺癌发病率的重要途径.已有的流行病学研究证明,身体活动可以显著降低罹患乳腺癌的风险.通过综合近年来国际主流文献对身体活动干预乳腺癌发生的机制研究,阐述身体活动干预乳腺癌的可能的生物学途径,尤其是对乳腺癌生物标记物的干预效果,这些生物指标主要包括身体质量指数、雌/雄激素、胰岛素耐受、脂肪因子以及TNF-a、Ⅱ-6等炎症因子.女性长期进行中等强度以上的锻炼,可以通过控制体重、减少脂肪、降低循环雌激素水平、改善胰岛素耐受、调控脂肪因子以及拮抗炎症因子等生物学途径预防乳腺癌的发生.由于雌激素代谢、胰岛素敏感性、脂肪因子合成等均与脂肪组织有关,因此,通过身体活动控制体重是预防乳腺癌的核心.建议重视长期跟踪实验及对多种人群的干预研究;在实验中需对身体活动的类型及运动强度、持续时间等进行详细阐述,进一步改进评估方法. 相似文献
20.
目的:对比分析大中学生对肿瘤早期检查的认知和需求。方法:选取金华市1所中学和1所大学学生共568名进行调查与分析。结果:中学生对肿瘤相关的健康生活方式水平认知程度比大学生的认知程度低,中学生在对肿瘤可防可治和肿瘤早期筛查项目的认识程度低,大学生对肿瘤早期检查的态度比中学生更积极。结论:大中学生对肿瘤早期检查的认知程度较低,有关学校尤其是中学应重视开展肿瘤早期发现的健康教育工作。 相似文献