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1.
The effect associated with the substitution of adenine (A) for guanidine (G) in the promoter region of the apolipoprotein AI gene (?75 bp) with plasma apo AI and high-density lipoprotein (HDL) levels was investigated in the European Atherosclerosis Research Study (EARS). This is a study of healthy offspring (cases) of fathers who had suffered premature myocardial infarction (MI) before age 55 years (n = 565) and age- and sex-matched controls (n = 1,078) from 12 European countries, divided into 5 regions based on geography and language. The frequency of the polymorphism was not significantly different among the regions and the relative frequency of the rare A allele was similar in cases and controls (0.159 vs. 0.142) combining data from all regions. Individuals with one or more A allele had significantly higher plasma apo AI levels (P < 0.05) than individuals homozygous for the G allele. This effect was consistent in all regions. The data were analyzed separately in males and females. In females, those with one or more A allele had significantly higher apo AI levels (P = 0.05) than individuals homozygous for the G allele, and this raising effect of the A allele was greater in cases than controls for both apo AI (5.23% vs. 1.56%) and HDL (4.48% vs. 1.89%). In males, the A allele was associated with higher levels of apo AI and HDL, but the effect was much smaller and the differences did not reach statistical significance. In the females, where the effect of the A allele was strongest, the effect on apo AI associated with genotype was evident in non-smokers, and individuals with one or two A alleles had 3.6% higher apo AI and 3.14% higher HDL levels than individuals homozygous for the G allele. However, in the female smokers the raising effect of the A allele was greatly reduced (0.56%). Thus genetic variation in the promoter region of the apo AI gene is associated with differences in apo AI and HDL levels in healthy individuals throughout Europe, but the effect is modulated by gender, environmental factors such as smoking, and a family history of MI. 相似文献
2.
本实验用分析基因限制性内切酶片段长度多态性(Restriction fragment length olymorphisms,RFLPs)技术,检测到中国人载脂蛋白AI(Apolipoprotein AI。Apo AI)基因3′端存一PstI多态位点,并发现该多态位点与低高密度脂蛋白(HDL)血症及冠心病有较密切的关系。 相似文献
3.
Norma A. Vavatsi Sophia A. Kouidou Paraschos N. Geleris Christos Tachmatzidis Theodoros Gikas Demetrios K. Tsifodimos Antonios C. Trakatellis 《Clinical genetics》1995,47(1):22-26
Restriction fragment length polymorphisms (RFLPs) at the apolipoprotein AI-CIII-AIV gene cluster and their association with coronary artery disease (CAD) and lipid levels were studied in a Northern Greek population. Ninety-five patients with CAD and fifty-four normal controls, angio-graphically proven, were included in this study. Using genomic hybridization techniques, three polymorphic restriction sites were identified at this locus: the PstI at the 3' end of the apoAI gene, the SacI at the 3' non-coding region of the apoCIII gene and the PvuII at the intergenic region between the apoCIII-AIV genes. The rare allele (P2) arising from the absence of the PstI restriction site was observed with a significantly higher frequency (p<0.01) in patients compared to normals (0.11 vs 0.02). In contrast, the rare allele for the SacI polymorphic site had a similar distribution among patients and controls (0.12 vs 0.16). The same was observed for the PvuII RFLP (0.04 vs 0.05). Correlation of lipid and apolipoprotein AI levels with the three RFLPs revealed no significant association, although apo AI and HDL were lower in patients with the P2 allele. Thus, in this Greek population, only the PstI polymorphism, among the polymorphic restriction sites examined, appears to be associated with CAD. 相似文献
4.
Immunohistochemical characteristics of duodenal adenomas in familial adenomatous polyposis with special reference to cell kinetics 总被引:4,自引:0,他引:4
The duodenum is the second most frequent site of cancer in patients with familial adenomatous polyposis (FAP). The main objective of this study was to evaluate the cell kinetics in duodenal and ampullary adenomas in FAP. The endoscopic and biopsy findings of duodenal adenomas in 22 FAP subjects and 18 non-FAP subjects were compared. Adenomas in FAP included 15 ampullary adenomas and 17 nonampullary adenomas. The cell kinetics was evaluated by immunohistochemistry for Ki-67, p53, bcl-2, and cyclooxygenase 2 (COX2), and the apoptotic index (AI) as determined by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) method. Any correlations between the indices for cell kinetics and the endoscopic findings were identified. All 50 adenomas were histologically verified to be tubular adenoma with low-grade dysplasia. Neither the expression of Ki-67, p53, bcl-2, and COX2 nor the AI differed substantially between FAP and non-FAP subjects. In patients with FAP, duodenal adenoma tended to have a higher Ki-67-labeling index than the ampullary adenoma (54.3 +/- 11.3 versus 46.8 +/- 12.7; .05 < P < .1). In addition, the Ki-67-labeling index in endoscopically normal or slightly enlarged ampullary adenoma was significantly higher than that in markedly enlarged ampullary adenoma (51.8 +/- 11.4 versus 39.4 +/- 11.3; P < .05). Duodenal adenoma in FAP subjects was not found to have a higher proliferative activity or a smaller degree of apoptosis compared with those in non-FAP subjects. The smaller proliferative activity in larger ampullary adenoma may thus be related to the static nature of ampullary adenoma in FAP. 相似文献
5.
目的探讨被转入的人SR-AI基因的整合与复制情况及其对小鼠繁育的影响.方法采用类似系祖建系的方法,对人SR-AI转基因小鼠的2、3534、3560、3638、3639五个系列进行了繁育.并用PCR和Southermblot的方法,检测五个系列小鼠尾组织的DNA样品.结果五个系列小鼠共产仔431只,PCR检出阳性小鼠178只,阳性率为41.2%.在3639系的F1、F2、F3代及纯合子转基因鼠中PCR阳性率分别为47.8%、71.3%、75%和100%.结论人SR-AI基因在子代鼠中能稳定遗传,且对生殖和发育无明显影响. 相似文献
6.
目的明确人SR-AI转基因小鼠的一些形态、脏器、血液学和血浆脂质参数,为人SR-AI转基因小鼠模型的应用提供相关依据.方法用游标卡尺和电子称量天平测量人SR-AI转基因小鼠的吻长、眶间距、体长、尾长及12个脏器系数并与C57BL/6J小鼠进行比较分析;用SysmexK-4500型全血自动多参数血液分析仪检测其血液学指标;并用酶法分别测定血浆总胆固醇、甘油三酯和高密度脂蛋白胆固醇含量.结果人SR-AI转基因小鼠外部形态指标和脏器系数与C57BL/6J小鼠比较差异没有显著意义(P>0.05);转基因小鼠的各项血液学指标无明显改变,血脂蛋白成分的改变亦未显示统计学意义(P>0.05),甘油三酯的浓度略有增高(P<0.05).结论人SR-AI转基因小鼠的外部形态指标、脏器系数及各项血液学指标均无明显改变,适合用作动脉粥样硬化模型的研究. 相似文献
7.
Effects of Red Palm Oil on Serum Lipids and Plasma Carotenoids Level in Chinese Male Adults 总被引:2,自引:0,他引:2
Objective Effects of red palm oil on major plasma carotenoids, tocopherol, retinol and serum lipids were evaluated when used in Chinese diet. Methods Red palm oil group (RPO) composedof 20 male subjects(aged 18-32) and soybean oil group (SBO) composed of 22 male subjects 相似文献
8.
肺癌是世界上最常见的恶性肿瘤之一,也是全球癌症死亡的主要原因[1]。近年来,随着免疫检查点抑制剂(immune checkpoint inhibitors,ICIs) 的应用、发展与兴起,一小部分晚期非小细胞肺癌(non-small cell lung cancer,NSCLC) 患者可从中获益。随着对ICIs药物应用后治疗效果的观察,与化疗药物及靶向药物可引起的典型反应,包括完全缓解(complete response,CR)、部分缓解(partial response,PR)、疾病稳定(stable disease,SD)、疾病进展(progressive disease,PD)比较,ICIs可引起另一种非典型反应模式,包括超进展、假性进展、分离反应等。与前两种非典型反应模式比较,目前的研究数据对分离反应的研究报道相对较少。本文回顾一些分离反应的研究,探讨其意义并思考其后续治疗方法。 相似文献
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