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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
31.
AbstractThe aim of this study is to clarify the possible association between methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism and pre-eclampsia in Hakka pregnant women in southern China. Pre-eclampsia and normal pregnant women were consecutively collected and MTHFR C677T genotypes were determined by the DNA sequencing method. One hundred and thirteen pre-eclampsia patients were CC homozygote (113 of 191, 59.2%), 68 of 191 (35.6%) were CT heterozygote, and 10 of 191 (5.2%) were TT homozygote, with the frequency of the T allele equal to 0.77. This is in comparison with the normal control group where 106 of 202 (52.5%) were CC homozygote, 83 of 202 (41.1%) were CT heterozygote, and 13 of 202 (6.4%) were TT homozygote, with the frequency of the T allele equal to 0.27. No statistically significant differences were observed in genotype or allele frequencies between the pre-eclampsia and normal control for the C677T polymorphism of MTHFR gene (p?>?.05). The findings of this study suggest that polymorphisms of MTHFR C677T genes were not associated with pre-eclampsia in Hakka pregnant women from southern China, but additional studies are necessary to explore the mechanisms involving it. 相似文献
32.
目的:探讨鼠双微体基因2(MDM2) T309G基因多态性与前列腺癌相关性。方法:用酚氯法提取全基因组DNA,应用聚合酶链反应、限制性内切酶的方法检测100例前列腺癌患者和100例健康男性的MDM2 T309G基因多态性。结果:病例组中G、T等位基因型频率分别为52.5%、47.5%,对照组中G、T等位基因型频率分别为40.5%、59.5%,MDM2 T309G基因型在两组的分布有显著性差异,TT基因型在对照组分布频率明显增高(P<0.05)。结论:MDM2 T309G基因型在病例组和对照组的分布存在明显差异,G等位基因与前列腺癌发病增加相关。 相似文献
33.
Rafaela Soares Senra da CostaIlce Ferreira da Silva 《Asian Pacific journal of cancer prevention》2020,21(9):2485-2491
Background: Benign breast disease (BBD) is one of main breast cancer risk factors. Dysfunctions on p53 protein, which has a genome protective role, have been related to breast cancer developments. However, its role on BBD development is still unclear. Methods: A systematic review of literature was proceeded according to PRISMA-P guidelines. PubMed, BVS, MEDLINE and Scholar Google were used as databases, complemented by a manual search in articles references. Articles searches were conducted from May to July 2019 and publications in English, Spanish and Portuguese were selected. P53 expression was set as outcome among women with BBD and were included only articles with good quality according STROBE tools. Data concerning p53 expression frequencies were independently extracted by two review authors, and eligible articles were synthesized. Results: From 12 studies selected for this review, the majority analyzed p53 expression in non-proliferative lesions and general p53 expressions ranged from 0 to 100%. P53 expression was more frequently observed in cases series studies (91.7%) and in studies conducted in Occidental Europe (41.7%). P53 expression was more frequent among tissues with fibrocystic disease (22.5%) and fibroadenoma (22.5%). Conclusion: When compared with all breast tissues types, benign breast disease corresponds to 34.39% of p53 expression. Second outcomes were not evaluated because the heterogeneity observed in selected studies. In addition, more studies considering ethnicity and benign breast disease classification should also be considered for further analysis. 相似文献
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35.
《Clinical lung cancer》2020,21(2):171-176
BackgroundPatients with lung cancer continue to smoke owing to complex factors. Failure to quit smoking (defined as nicotine dependence) is significantly associated with genetic status. This study aimed to investigate the relationship between polymorphisms in nicotine dependence genes and smoking status after the diagnosis of lung cancer.Patients and MethodsA total of 240 patients with lung cancer were included from July 2017 to March 2018. According to the actual smoking condition after lung cancer diagnosis, eligible patients were divided into 3 groups: the never-smoking group, the failure to quit smoking group, and the successful smoking cessation group. Fagerstrom Test for Nicotine Dependence scores were used to evaluate the smoking status of each group. Three nicotine-dependent genes with 6 loci were detected.ResultsAmong the 240 patients, 86 were never-smokers, 51 failed to quit smoking, and 104 successfully quit smoking. The initial age of smoking in the failure to quit smoking group was significantly younger than those in the successful smoking cessation group (P = .001). There was a significant difference in the GG and AG and AA genotype distributions of CHRNA3 (rs578776) among the 3 groups (P = .003). There was also a significant difference in the distribution of CHRNA4 (rs2229959) genotypes among the 3 groups (P = .003). However, there was no significant difference in the genotype distribution of CHRNA5 (rs588765) among the 3 groups (P = .277).ConclusionsGene polymorphisms of CHRNA3 (rs578776) and CHRNA4 (rs1044396 and rs2229959) were associated with the success of smoking cessation after the diagnosis of lung cancer, which should be considered in the management of smoking cessation after patients are diagnosed with lung cancer. 相似文献
36.
Sen Yang Dongfang Tang Yu C. Zhao Hongliang Liu Sheng Luo Thomas E. Stinchcombe Carolyn Glass Li Su Sipeng Shen David C. Christiani Qiming Wang Qingyi Wei 《International journal of cancer. Journal international du cancer》2020,147(2):392-403
The endosome is a membrane-bound organ inside most eukaryotic cells, playing an important role in adaptive immunity by delivering endocytosed antigens to both MHC class I and II pathways. Here, by analyzing genotyping data from two published genome-wide association studies (GWASs), we evaluated associations between genetic variants in the endosome-related gene-set and survival of patients with nonsmall cell lung cancer (NSCLC). The discovery included 44,112 (3,478 genotyped and 40,634 imputed) single-nucleotide polymorphisms (SNPs) in 220 genes in a singlelocus analysis for their associations with survival of 1,185 NSCLC patients from the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial. After validation of the 821 survival-associated significant SNPs in additional 984 NSCLC patients from the Harvard Lung Cancer Susceptibility Study, 14 SNPs remained significant. The final multivariate stepwise Cox proportional hazards regression modeling of the PLCO dataset identified three potentially functional and independent SNPs (i.e., KIF16B rs1555195 C>T, NEDD4L rs11660748 A>G and rs73440898 A>G) with an adjusted hazards ratio (HR) of 0.86 (95% confidence interval [CI] = 0.79–0.94, p = 0.0007), 1.31 (1.16–1.47, p = 6.0 × 10−5) and 1.27 (1.12–1.44, p = 0.0001) for overall survival (OS), respectively. Combined analysis of the adverse genotypes of these three SNPs revealed a trend in the genotype-survival association (ptrend < 0.0001 for OS and ptrend < 0.0001 for disease-specific survival). Furthermore, the survival-associated KIF16B rs1555195T allele was significantly associated with decreased mRNA expression levels of KIF16B in both lung tissues and blood cells. Therefore, genetic variants of the endosome-related genes may be biomarker for NSCLC survival, possibly through modulating the expression of corresponding genes. 相似文献
37.
《药学学报(英文版)》2020,10(4):667-679
Combination therapy has shown its promise in the clinic for enhancing the efficacy of tumor treatment. However, the dose control of multiple drugs and their non-overlapping toxicity from different drugs are still great challenge. In this work, a single model drug, paclitaxel (PTX), is used to realize combination therapy and solve the problems mentioned above. Either PTX or its triphenylphosphine derivative (TPTX) is encapsulated in galactose-modified liposomes (GLips) to obtain GLips-P or GLips-TP, which are simply mixed in different ratios to finely control the proportion of PTX and TPTX. These mixed liposomes, GLips-P/TP, feature a cascade target delivery of PTX, from tissue to cell, and then to organelle. PTX plays a primary role to cause the cytotoxicity by microtubule bindings in cytoplasm, while TPTX is proved to increase the intracellular levels of caspase-3 and caspase-9 that cause apoptosis via a mitochondria-mediated pathway. Notably, GLips-P/TP 3:1 exhibited the significant drug synergy in both cytotoxicity assay of HepG2 cells and the treatment efficacy in Heps xenograft ICR mouse models. This work not only demonstrates the great promise of a cascade targeting delivery for precise tumor treatment, but also offers a novel platform to design combinatory therapy systems using a single drug. 相似文献
38.
《Drug metabolism and pharmacokinetics》2020,35(3):321-328
We performed a caffeine (N-3-methyl-13C) breath test (CafeBT) to determine whether it can be employed to identify caffeine metabolism-associated single nucleotide polymorphisms. The study included 130 healthy adults (mean age: 21.9 years). Saliva was collected using an Oragene®•DNA saliva collection kit. Breath samples were collected from the subjects. The subjects orally ingested 100 mg 13C-caffeine dissolved in distilled water. Subsequently, breath samples were collected in bags every 10 min for a total of 90 min. An analysis of 13CO2 in the expired breath was performed by infrared spectroscopy, and the sum of Δ13CO2 over 90 min (S90m) was calculated. DNA from saliva samples was genotyped using TaqMan® SNP Genotyping for the following genes: cytochrome P4501A2: rs762551, rs2472297, aryl-hydrocarbon receptor (rs4410790), and adenosine A2A receptor (rs5751876). All subjects had the genotype CC in rs2472297 alleles. No significant difference was observed in S90m among the genotypes of rs762551 and rs5751876; however, a significant difference was found in S90m among the genotypes of rs4410790 (C > T). Our findings suggest that the N-3 demethylation of caffeine is dependent on the rs4410790 allele and that CafeBT may be used to determine rs4410790 genotypes. 相似文献
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