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91.
Orathai Tangvarasittichai Watchiravut Jaiwang Surapon Tangvarasittichai 《Indian journal of clinical biochemistry : IJCB》2015,30(1):55-58
Increased levels of plasma DNA have frequently been noticed in the blood plasma of cancer patients. The possibility of using plasma DNA level as the indicator of tumor stage in breast cancer was investigated in plasma samples obtained from 100 breast cancer patients and 100 healthy women who were included as controls. Circulatory plasma free DNA was extracted from plasma samples and quantified by fluorometer. The median concentration of plasma DNA in the plasma samples from breast cancer patients classified by TNM staging system as stage I, II, III, IV and breast surgical patients were 0.5, 235, 422, 1,280 and 0.5 ng/ml, respectively. The level of plasma DNA in the stage II- IV group was significantly higher than those in the surgical group with breast cancer and control group (P value < 0.001). The plasma DNA concentration in stage II, III and IV of breast cancer were higher when compared with healthy group. These tumor size, TNM stage and metastasis were significantly correlated with plasma DNA. The cut point of 120 ng/ml was early screening and treatment follow up breast cancer. 相似文献
92.
马云彤 《西安文理学院学报》2010,13(1):44-47
拓扑异构酶Ⅰ在DNA翻译和转录过程中催化单链DNA的断裂和连接,从而松弛DNA超螺旋,促进复制与转录的进行.拓扑异构酶Ⅰ抑制剂能够阻断DNA链的再连接,结果导致TopⅠ断裂复合物的积累,抑制复制和转录,造成DNA损伤,从而激活DNA损伤检验点,抑制细胞生长和诱发凋亡。喜树碱是最早发现、也是最重要和最广泛使用的拓扑异构酶Ⅰ抑制剂.细胞周期中DNA损伤、修复和检验点应答的分子机制是目前生命科学研究热点,而喜树碱已成为进行相关研究的重要的药理学工具. 相似文献
93.
概述了近年来国内外在氨基酸席夫碱金属配合物领域的研究,探讨了氨基酸席夫碱配合物与DNA之间作用机理,并对该领域的研究前景作出展望. 相似文献
94.
目的探究长期运动训练对青年男性淋巴细胞凋亡及线粒体DNA(mtDNA)修复酶(8-氧鸟嘌呤DNA糖基化酶,OGG1)的影响及可能机制。方法训练组为20名男子足球专业运动员,对照组为20名男子大学生。2组均在功率自行车上完成递增负荷力竭运动。运动前和运动后即刻采集静脉血。流式细胞法检测淋巴细胞凋亡率,比色法检测超氧阴离子和羟自由基含量和Caspase-3,Caspase-9活性,高效液相色谱法检测mtDNA中8-氧鸟嘌呤(8-oxodG)含量,Western-blotting法检测线粒体OGG1蛋白(mtOGG1)表达水平。结果运动前和运动后,训练组与对照组比较,超氧阴离子、羟自由基、Caspase-3,Caspase-9活性、8-oxodG降低,OGG1升高;运动后,训练组与对照组比较,淋巴细胞凋亡率降低。对照组和训练组在运动后与运动前比较,淋巴细胞凋亡率、超氧阴离子、羟自由基、Caspase-3,Caspase-9活性和8-oxodG均升高,但训练组升高幅度低于对照组;运动后对照组OGG1降低,而训练组OGG1升高。结论一次性力竭运动诱导产生高水平ROS,并抑制mtOGG1表达,使mtDNA氧化损伤,促进淋巴细胞凋亡;长期耐力训练可通过抑制ROS生成,并提高mtOGG1表达,抑制运动性淋巴细胞凋亡。 相似文献
95.
Alex Livy Sayhean Lye Chahil K. Jagdish Nurul Hanis Velapasamy Sharmila Lian Wee Ler Bagali Pramod 《Indian journal of clinical biochemistry : IJCB》2012,27(1):28-33
Buccal cell usage has been shown by many to be a cost effective and safe method to isolate DNA for various biological experiments
especially large epidemiological studies (Garcia-Closas et al. Cancer Epidemiol Biomarkers Prev 10:687–696, 2001). Non-invasive DNA collection methods are preferred over phlebotomy in order to increase study participation and compliance
in research centers and for sick patients in hospital settings. There have been conflicting reports about the methodology
and results obtained from using buccal DNA. It is not very clear if phlebotomy can be confidently replaced by buccal cell
DNA. It is often left for the user to take an intelligent decision. To address this issue, we compared the performance of
buccal and blood DNA from same subjects in a genotyping experiment and this paper reports the results. Cotton swab derived
buccal cells were scraped from the inner side of cheeks from 16 subjects, and blood was also drawn from the same 16 subjects
participating in a genotypic association study of a lipid disease. The DNA quality was assessed by resolving on agarose gels,
checking purity (A260/A280) and finally by microarray hybridization. This study showed that DNA degradation affects the total
yield and performance of the buccal DNA when compared to the blood DNA in microarray based genotyping. Genotyping results
can be seriously compromised if care is not taken to check the quality and yields of such specimens. 相似文献
96.
结合生物中心法则,提出了企业文化中心法则。企业文化的三个层次——核心价值观、制度/技术文化以及行为/形象文化分别对应于生物大分子DNA、RNA和蛋白质。企业文化三层次间也存在着信息复制、转录和转译的过程。企业文化中心法则的构建,为我们探讨企业文化层次要素间的信息传递、企业文化的运行演化规律以及构建良好的企业文化提供了新的视角和思路。 相似文献
97.
《Communication monographs》2012,79(2):271-290
Human genetics and racial identity converge pointedly in the family narrative. Until recently, genetics, racial identity, and family narrative were all rather malleable concepts in the public arena. All were presented in anecdotal form for the most part, and were often based on certain social conventions. The interjection of popularly available ancestry DNA data adds an additional piece of information to the discussion of genetics, race, and narrative. Using the framework of both narrative theory and theory of social construction, this work uses quantitative and qualitative data to explore how individuals react to ancestry DNA findings and to consider if and how this information will change narratives, behaviors, and perspectives. We also explore whether one's racial identification makes a difference in initial accuracy and if there is a difference among racial groupings in terms of change in census identification based on knowledge of their DNA profile. 相似文献
98.
对纯化的家蚕微孢子的DNA抽提及PCR检测灵敏度进行了研究。结果显示:以0.1mol/L K2CO3 0.1mol/L KHCO3作为诱导剂诱导人工纯化的微孢子发芽是最佳选择,配合proteaseK法,能较好地抽提微孢子的DNA;PCR检测灵敏度研究发现,最低检测微孢子核酸浓度是3.25×10-2pg(25μl反应体系),溶液中只要有4粒微孢子即可检出。 相似文献
99.
本文应用流式细胞术(Flow Cytometry,FCM)检测了102例石蜡包埋的乳癌组织的细胞核DNA含量,并探讨了DNA指数(DNA Index.DI)和S期细胞比例(S-phase Fraction,SPF)与临床预后因素及病人术后生存状况的关系。结果显示:16例为DNA二倍体,8例近二倍体,78例(77%)非整倍体。非整倍体癌较二倍体/近二倍体癌的SPF高。DI值与组织学分级、淋巴结状况、原发肿瘤大小和临床分期密切相关,而与病人诊断时的年龄无关。淋巴结转移阳性组较阴性组、晚期肿瘤(Ⅲ、Ⅳ期)比早期肿瘤(Ⅰ、Ⅱ期)的DI值高(P<0.05),而非整倍体率仅有降低的趋势但无显著性差异,说明DI值作为一个预后参数比倍性分析统计效率高。SPF与病人的各预后因素及生存情况无明显关系。二倍体/近二倍体癌病人较非整倍体癌病人的生存率高、无瘤生存时间长,说明流式细胞术DNA含量测定确实可为乳癌病人的预后提供有价值的信息。 相似文献
100.
方法:观察了老年小鼠服旱莲草水煎剂后,脾淋巴细胞IL2、MAF的分泌和DNA合成的变化;并观察了旱莲草体外对脾淋巴细胞DNA合成的影响.结果:①使老年小鼠脾淋巴细胞分泌IL2逐渐减少(P<0.001),并呈剂量依赖关系(r=-8988);②体内外实验表明高浓度旱莲草水煎剂抑制脾淋巴细胞在ConA激活后的DNA合成,但无ConA时DNA合成不受影响;③老年小鼠脾淋巴细胞分泌MAF能力明显低于青年小鼠(P<0.05),灌服旱莲草24g/kg×7d使老年小鼠脾淋巴细胞分泌MAF能力明显增强(P<0.05). 相似文献