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排序方式: 共有241条查询结果,搜索用时 15 毫秒
141.
Jigna Joshi Apexa Raval Urja Desai Vinal Upadhyay Mansi Bhavsar Kanisha Shah Rakesh Rawal Harsha Panchal Franky Shah 《Indian journal of clinical biochemistry : IJCB》2021,36(1):51
In the era of the targeted therapy identification of EGFR mutation detection in lung cancer is extremely helpful to predict the treatment efficacy of EGFR tyrosine kinase inhibitors (TKIs). Unfortunately, the inadequacy and quality of the biopsy samples are the major obstacles in molecular testing of EGFR mutation in lung cancer. To address this issue, the present study intended to use liquid biopsy as the non-invasive method for EGFR mutation detection. A total of 31 patients with an advanced stage of lung cancer were enrolled in the study from which cell-free DNA (cfDNA) and FFPE tissue DNA was extracted. Extracted DNA samples were analyzed for further EGFR exon specific mutation analysis by ARMS-PCR. Data were analyzed statistically using SPSS software. In cfDNA samples, the prevalence of wild type EGFR was 48% while the prevalence of TKI resistant and TKI sensitive mutations were 3%. Conversely, in tissue DNA samples, the prevalence of wild type, TKI sensitive and TKI resistant mutations were 48%, 19%, and 3%, respectively. The overall concordance of EGFR mutation between cfDNA and tissue DNA was 83%. McNemar’s test revealed that there was no significant difference between EGFR expression of cfDNA and tissue DNA samples. Additionally, the significant-high incidence of TKI resistant mutations was observed in tobacco habituates, indicating the role of carcinogens present in the tobacco in developing resistant mutations. In conclusion, our data suggest that evaluation of EGFR mutation from cfDNA samples is practicable as a non-invasive tool in patients with advanced-stage of lung cancer. 相似文献
142.
酸奶在储存过程中菌群结构变化研究 总被引:1,自引:0,他引:1
张红琳 《南京晓庄学院学报》2010,26(6):44-46
为了探究酸奶储存过程中微生物菌群结构的变化,为其长期贮存奠定理论基础.采用酚/氯仿法抽提细菌基因组DNA,以此作为PCR反应的模板,进行16S rDNA基因有效扩增,并将PCR扩增产物进行DGGE电泳.用Bionumerics软件对DGGE分子指纹图谱进行舌苔菌群结构相似性分析.实验结果表明,采用该方法成功地扩增出16S rDNA V3区片段,为230 bp.DGGE分子指纹图谱结果表明,1、2号酸奶样品高相似性为93%,1-3号与4-7号的相似仅为6%,表明酸奶贮存过程中,菌群结构发生了变化. 相似文献
143.
Francesc Codony Bárbara Adrados Leonardo Martín Pérez Mariana Fittipaldi Jordi Morató 《Journal of Zhejiang University. Science. B》2009,10(12):867-869
The Catabacteriaceae is a new bacterial family with a unique member: Catabacter hongkongensis is a strictly anaerobic, non-sporulating, Gram-positive coccobacillus that is phylogenetically related to some clostridial
clusters. Little is known of its epidemiology and environmental distribution, but the inclusion of its 16S rRNA gene sequence
in GenBank has allowed it to be detected qualitatively. As a first approach for prospective surveys, a real-time polymerase
chain reaction (PCR) procedure to identify C. hongkongensis has been developed. The presence of Catabacteriaceae in 29 water bodies subjected to possible human or animal impact has
been investigated. Four of them were positive. The results confirm that highly polluted water can contain C. hongkongensis. 相似文献
144.
145.
自主开发的“信息港湾”系统,主要满足酒店、宾馆、医院、学校等行业客户的通信业务实时计费结帐的需求.该系统涵盖了固定电话、小灵通和宽带三大主营业务,实现了多种不同的话费查询方式 相似文献
146.
147.
目的:使用免疫BMPs,对含有大肠杆菌O157的粪便标本,进行目标病原菌的捕获和洗净,建立一种快速纯化细菌PCR反应模板的方法。方法:将大肠杆菌O157抗体接种于BMPs表面,制成免疫BMPs。使用免疫BMPs,对含有不同浓度大肠杆菌O157的粪便标本,进行目标病原菌的捕获、分离和洗净,再使用洗净的病原菌制备PCR反应模板。作为对照,对含有不同浓度大肠杆菌O157的粪便标本,常规进行增菌培养及鉴别培养后,制备细菌的PCR反应模板,或粪便标本直接制备PCR反应模板。结果:使用免疫BMPs处理后制备PCR反应模板,与通过常规增菌培养和鉴别培养后制备PCR反应模板,PCR检测结果一致。而粪便标本直接取样制备PCR反应模板,大肠杆菌O157低浓度时,PCR检测的阳性率较低。结论:利用免疫BMPs捕获自然标本(粪便)中的目标病原菌,通过分离和洗净,去除标本中存在的PCR反应抑制物等影响因素,可省略增菌培养及鉴别培养,快速纯化目标病原菌的PCR反应模板。 相似文献
148.
当前的反竞争情报领域,学者主要关心情报保护问题,而忽视情报泄密后的危机管理问题。本文基于持续性管理的思维,提出了情报泄密危机的生命周期和危机管理模型(PECR),阐述了该模型各个阶段的任务重点及相互关系。本文认为情报泄密危机的管理比情报保护往往还要重要,这项研究可为企业反竞争情报研究提供新的思路,并为企业关键性情报泄密事故的处理提供理论和实践指导。 相似文献
149.
S. Pandey Ravi Ranjan R. M. Mishra Sw. Pandey R. Saxena 《Indian journal of clinical biochemistry : IJCB》2012,27(3):314-317
Hemoglobin D exist in four form; HbD trait, HbD-thalassemia, HbD sickle cell and HbD homozygous. HbD trait and HbD homozygous generally asymptomatic condition but when HbD co-inherit with thalassemia and sickle cell anemia, produces clinically significant conditions like chronic hemolytic anemia. Here we present a case of HbD Punjab with α 3.7 kb deletion and IVS-1-5 β-thalassemia across a family. Diagnosis of HbD patient was performed by high performance liquid chromatography and complete blood count was measured by automated cell analyzer. Molecular study for common alpha deletions done by Gap-PCR while beta thalassemia mutation identified by ARMS-PCR. Case was clinically significant due to the inheritance of HbD/β+thalassemia genotype. Thus observed case behaved like thalassemia intermedia due to co-existence of α 3.7 deletions with IVS 1-5 β-thalassemia mutation in HbD Punjab patient. 相似文献
150.
谷胱甘肽S-转移酶(glutathione S-transferases ,GSTs)在昆虫代谢各种内源和外源性有害化合物的过程中起关键作用。重要水稻害虫稻纵卷叶螟(Cnaphalocrocis medinalis)的GST基因目前尚无研究。本实验克隆了一个稻纵卷叶螟delta家族GST基因的全长cDNA序列,命名为CmGSTd3(Genbank登录号KM433686)。CmGSTd3包含681 bp的开放阅读框,编码一个由226个氨基酸组成的蛋白。CmGSTd3蛋白是一个胞质GST ,与已知的昆虫delta家族GST 具有较高的同源性。在系统进化分析中,CmGSTd3与家蚕的delta家族GST聚在同一进化分支上。实时荧光定量PCR结果显示,CmGSTd3基因在稻纵卷叶螟幼虫阶段表达量最高,且主要表达于幼虫的中肠和脂肪体,由此推测其可能参与了体内异源毒物的代谢。本研究为探索CmGSTd3的生理功能奠定了前期基础。 相似文献