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11.
Chemokine are small, inducible pro-inflammatory cytokines involved in many biological processes, such as migration of leukocytes, atherosclerosis, angiogenesis, tumor growth, and metastasis. Chemokine are also known to influence tumor cell’s activity. Specifically, tumor cells express chemokine receptors in a non random manner suggesting a role of chemokine in metastatic destination of tumor cells. The present study was conducted to determine distribution of (Chemokine receptor 2) CCR2 V64I, Chemokine ligand 2 CCL2 I/D, and CCL2 2518 A>G gene polymorphisms in North Indian population and compare with different populations globally. Polymerase chain reaction (PCR)-based analysis was conducted in 200 normal healthy individuals of similar ethnicity. Allelic frequencies in wild type (GG) of CCR2 V64I G>A were 63 % G; CCL2 I/D 42 % II; CCL2 2518 A>G 40.5 % A. The minor variant allele frequency in our population was as follows: 19.5 % for CCR2 V64I, 35.5 % for CCL2 I/D, 35.3 % for CCL2 2518 A>G. We further compared frequency distribution for these genes with various published studies in different ethnicity. Our results suggested that frequency in chemokine genes exhibit distinctive pattern in India that could be attributed to ethnicity variation. This could assist in high-risk screening of human exposed to environmental carcinogens and cancer predisposition in different ethnic groups. Thus, they signify an impact of ethnicity and provide a basis for future epidemiological and clinical studies.  相似文献   
12.
本文概述了DNA分子标记的种类和最新研究进展,分子标记可以运用于甘薯遗传图谱的建立和基因定位,亲缘关系与遗传多样性的研究,分子标记辅助选择及品种纯度鉴定等方面。  相似文献   
13.
对广义百合科黄精族6属23种及铃兰族1属1种的叶绿体基因组trnK和rpl16两个基因片段进 行了PCR-RFLP分析,结果表明:trnK基因的PCR产物在各类群间几乎不存在长度变异,均约2600bp,而rpl16基因则在各属之间及黄精属内表现出长度变异,变异范围在1140~1320bp之间;限制性酶切位点的同源性分析显示,黄精属、竹根七属、鹿药属和舞鹤草属构成的狭义黄精族与铃兰族中的铃兰属有较近的亲缘关系,并支持将扭柄花属和万寿竹属从广义百合科黄精族中分出的观点;在狭义黄精族内,黄精属与竹根七属聚成一支,鹿药属与舞鹤草属聚成另一支,为探讨族内属间的系统演化关系提供了分子生物学方面的证据。另外,本研究结果支持将金佛山黄精从鹿药属转隶至黄精属的观点。  相似文献   
14.
研究目的 :探讨了 mt DNA D- loop多态性与澳大利亚自行车运动员的 VO2 max及优异耐力成绩的关系。研究结果 :前期研究发现虽然运动员组和对照组 VO2 max有显著性差异 ,但 mt DNA D- loop的多态性在两组的分布频率没有显著性差异  相似文献   
15.
In human tumors, somatic mutation frequently occur in K-ras gene at codon 12, which makes the K-ras protein hyper active leading to uncontrolled signaling for cell division: one of the important hall mark of cancer. In order to correlate mutations in K-ras to cause, response to treatment, disease progression and recurrence of Head and Neck Squamous Cell Carcinoma (HNSCC) the following study was undertaken. By using PCR–RFLP method prevalence of codon 12 in K-ras gene was studied in 56 HNSCC patients. High frequency of K-ras mutation was detected in codon 12 (60.71%). The result of this study helps us in understanding the role of K-ras somatic mutations in HNSCC patients and in designing novel treatment protocols for HNSCC patients.Electronic supplementary materialThe online version of this article (10.1007/s12291-020-00882-w) contains supplementary material, which is available to authorized users.  相似文献   
16.
本文用14种限制性内切酶对来自青海的蒙古族、贵州的苗族、云南各地的傈僳族、白族、彝族。傣族和基诺族共80个样本的线粒体DNA(mtDNA)进行了限制性片段长度多态性(RFLP)分析,有9种酶检测到多态,共计48种单倍型.结果表明:彝族和白族人群的mtDNA变异度较大;在与非洲、东南亚、美洲、欧洲人群的横向比较中发现一些典型的突变位点,如:10394c和8994e.  相似文献   
17.
目的:研究黑龙江汉族速滑运动员优秀耐力能力与肌型肌酸激酶基因(CKMM)A/G多态的关联性。方法:应用PCR-RFLP法测定120名黑龙江籍汉族健康大学生及25名黑龙江汉族耐力型速滑运动员CKMM基因A/G位点的基因型和等位基因的频率分布。结果:大学生等位基因频率为A=87%,G=13%,基因型频率为A/A=76%,A/G=22%,G/G=2%;速滑运动员等位基因频率为A=84%,G=16%,基因型频率为A/A=68%,A/G=32%,经卡方检验符合Hardy-Weinberg遗传平衡定律,两组的基因型频率和等位基因频率在男女间无显著性差异,与欧美人群相比有显著性差异,与我国北方汉族人及韩国人相比差异不具有显著性。两组间基因型频率和等位基因频率无显著性差异。结论:黑龙江汉族耐力型速滑运动员的优秀耐力素质与CKMM基因N coⅠ多态性无关,该位点不能作为其耐力素质选材的遗传学标记。  相似文献   
18.
目的:用PCR-RFLP技术,对慢性牙周炎患者龈下菌斑中厌氧菌进行分型.为建立更为合理的分型方法提供依据.方法:选取符合标准的慢性牙周炎患者,提取其龈下菌斑.厌氧条件下分离培养,获得厌氧菌菌株,在血平板培养基培养观察菌落的形态,通过染色观察菌株形态学特征,提取各菌株DNA,利用细菌16sDNA通用引物进行PCR扩增,以限制性内切酶MSP I对分离的22株厌氧菌的PCR扩增产物进行RFLP分型分析.结果:慢性牙周炎患者龈下菌斑中厌氧菌分为二大类.结论:采用PCR-RFLP用于厌氧菌的分型研究较为可靠,对于确定有争议菌种的分类具有重要的意义.  相似文献   
19.
In the search for a rapid and reliable method for identification of bacteria in blood and cerebrospinal fluid , we developed a unified set of primers and used them under polymerase chain reaction(PCR) to amplify the spacer regions between the 16s and 23s genes in the prokaryotic rRNA genetic loci . Spacer regions within these loci showed a significant level of length and sequence polymorphism across most of the species lines. A generic pair of priming sequences was selected from highly conserved sequences in the 16s and 23s genes occurring adjacent to these polymorphic regions. This single set of primers and reaction conditions were used for the amplification of the 16s-23s spacer regions for 61 strains of standard bacteria and corresponding clinical isolates belonging to 20 genera and 27 species, including Listeria, Staphylococcus and Salmonella species, et al. When the spacer amplification products were resolved by electrophoresis, the resulting patterns could be used to distinguish most of the bacteria species within the test group, and the amplification products of the clinical isolates clustered at the standard species level. Some species presenting similar pattern were further analyzed by HinfI or AluI digestion or DNA clone and sequences analysis in order to establish the specific 16s-23s rRNA gene spacer regions map. Analysis of 42 blood specimens from septicemic neonates and 6 CSF specimens from suspected purulent meningitis patients by bacterial culture and PCR-RFLP(Restriction Fregament Length Polymorphism) showed that 15 specimens of blood culture were positive(35.7%) in the 42 septicemic neonates; 27 specimens were positive(64.2%) by PCR, and that the positive rate by PCR was significantly higher than that by blood culture(P<0.01). Among the 6 CSF specimens, one specimen found positive by blood culture was also positive by PCR, two found negative by blood culture showed positive by PCR; all three were S.epidermidis according to the DNA map. One C.neoformans found positive by blood culture showed negative by PCR. The remaining two specimens were both negative by PCR and blood culture. These results indicated that the method of detecting bacterial 16s-23s rRNA spacer regions using PCR and RFLP techniques was rapid, sensitive and specific in the detection of bacterial infections; and so, has very important application in the clinical diagnosis of sepsis in neonates.  相似文献   
20.
 运用PCR方法分别从松科8属、9种植物中扩增出一长约2550bp的cpDNA片段,这一片段包括rbcL、trnR、部分accD及基因间的非编码区(相对于黑松cpDNA中的同源片段而言)。运用18种限制性内切酶对这一cpDNA片段进行酶切分析,共获得86个酶切位点,其中54个为变异位点。运用PAUP(version 3.1.1)和Mega(version 1.01)软件对数据进行分析,结果Wagner简约树和Neighbor-Joining树反映出的松科系统发育关系基本一致:银杉属、松属、黄杉属和落叶松属形成一个单系群,且银杉属与松属的亲缘关系更近于与另外二属的关系,但这一结果未得到Bootstrap分析的较强支持;落叶松属近缘于黄杉属;冷杉属近缘于油杉属。此外,松科中的冷杉亚科和落叶松亚科均不是单系类群,将松科划分为冷杉亚科、落叶松亚科和松亚科三个亚科的系统(郑万钧,傅立国,1978)是不自然的。  相似文献   
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