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排序方式: 共有4378条查询结果,搜索用时 15 毫秒
961.
Lei Li Jiangtao Yang Liyuan Zhang Qiu Chen Ye Tian 《Cell biochemistry and function》2014,32(3):241-248
Astrocytes, the most common cell type in the brain, play a principal role in the repair of damaged brain tissues during external radiotherapy of brain tumours. As a downstream gene of p53, the effects of Krüppel‐like factor 4 (KLF4) in response to X‐ray‐induced DNA damage in astrocytes are unclear. In the present study, KLF4 expression was upregulated after the exposure of astrocytes isolated from the murine brain. Inhibition of KLF4 expression using lentiviral transduction produced less double‐strand DNA breaks (DSB) determined by a neutral comet assay and flow cytometric analysis of phosphorylated histone family 2A variant and more single‐strand DNA breaks (SSB) determined by a basic comet assay when the astrocytes were exposed to 4 Gy of X‐ray radiation. These data suggest that radiation exposure of the tissues around brain tumour during radiation therapy causes KLF4 overexpression in astrocytes, which induces more DSB and reduces SSB. This causes the adverse effects of radiation therapy in the treatment of brain tumours. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
962.
R. E. Marioni I. J. Deary G. D. Murray F. G. R. Fowkes J. F. Price 《Genes, Brain & Behavior》2010,9(3):348-352
Several studies have found associations between inflammatory biomarker levels and cognitive ability. This study tested the relationship between polymorphisms in genes that are associated with or encode the biomarkers and cognitive ability and estimated lifetime cognitive change. Data came from the aspirin for asymptomatic atherosclerosis trial (n = 2091, mean age = 67.2 years ). Twelve single nucleotide polymorphisms (SNPs) were genotyped from five genes (IL‐1α, IL‐1β, IL‐6, HNF‐1A and F13A1). Cognition was assessed via administration of a five‐test battery of psychometric tests, which were used to derive a general intelligence factor, g. A vocabulary‐based cognitive test was also administered and adjusted for in the analysis to enable an estimation of lifetime cognitive change. Age‐ and sex‐adjusted analyses yielded one weakly significant association between the IL‐1α rs2856838 SNP and a measure of mental flexibility/processing speed (P = 0.044). Adjustment for the vocabulary‐based scores resulted in a single, significant association between the IL‐1α rs3783546 SNP and a measure of processing speed (P = 0.048). There is little evidence to suggest an association between SNPs in the inflammation‐related genes IL‐1α, IL‐1β, IL‐6, TCF‐1 and F13A1 and cognition in an elderly population of community‐dwelling Scottish citizens. 相似文献
963.
Tian Dong Chao Qi Lin Liu Gang Guo Cong Li Xiaogang Cui Shengli Zhang Qin Zhang Yi Zhang Dongxiao Sun 《Animal genetics》2014,45(5):740-744
With the Illumina BovineSNP50K BeadChip, we performed a genome‐wide association study (GWAS) for two pigmentation traits in a Chinese Holstein population: proportion of black (PB) and teat colour (TC). A case–control design was used. Cases were the cows with PB <0.30 (n = 129) and TC <2 points (n = 140); controls were those with PB >0.90 (n = 58) and TC >4 points (n = 281). The RM test of roadtrips (version 1.2) was applied to detect SNPs for the two traits with 42 883 and 42 741 SNPs respectively. A total of nine and 12 genome‐wide significant (P < 0.05) SNPs associated with PB and TC respectively were identified. Of these, two SNPs for PB were located within the KIT and IGFBP7 genes, and the other four SNPs were 23~212 kb away from the PDGFRA gene on BTA6; nine SNPs associated with TC were located within or 21~78.8 kb away from known genes on chromosomes 4, 11, 22, 23 and 24. By combing through our GWAS results and the biological functions of the genes, we suggest that the KIT, IGFBP7, PDGFRA, MITF, ING3 and WNT16 genes are promising candidates for PB and TC in Holstein cattle, providing a basis for further investigation on the genetic mechanism of pigmentation formation. 相似文献
964.
Ondrej Belan Consuelo Barroso Artur Kaczmarczyk Roopesh Anand Stefania Federico Nicola O’Reilly Matthew D. Newton Erik Maeots Radoslav I. Enchev Enrique Martinez-Perez David S. Rueda Simon J. Boulton 《Molecular cell》2021,81(5):1058-1073.e7
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In the past year, microarray technologies have moved beyond the proof-of-principle stage. Microarrays are now being used for genome-wide expression monitoring, large-scale polymorphism screening and mapping, and for the evaluation of drug candidates. 相似文献
969.
Kyusik Yun Seonhee Park Hyeonbong Pyo Seunghwan Kim Sooyeul Lee 《Biotechnology and Bioprocess Engineering》1999,4(1):72-77
An antibody containing a genetically engineered lipid group at the N-terminus and a hexahistidinyl tag at the C-terminus (Lpp-scFv-His6)
was immobilized in an oriented manner on the surface of liposomes. Liposomes, consisting of antibody and phosphatidylcholine,
have been prepared and imaged by AFM. For AFM visualization, the resulting liposomes were bound on the surface of mica by
two different mechanisms. The histidine tags present in the antibody molecules of the immunoliposome were anchored to the
NiCl2 treated mica surface. Alternatively, the immunoliposomes were immunochemically bound on antigen-coated mica surface. Both
approaches yielded liposomes which were clearly imaged without damage by AFM in ambient condition. 相似文献
970.
Chikara Sato Masahiko Sato Akio Iwasaki Takeshi Doi Andreas Engel 《Journal of structural biology》1998,121(3):314-325
The voltage-gated sodium channel generates the action potential. This 300-kDa protein has four homologous regions, which are also homologous to the voltage-sensitive tetrameric potassium channel. We isolated sodium channels fromElectrophorus electricuselectroplax by detergent solubilization and immunoaffinity chromatography and studied their structure by electron microscopy of negatively stained specimens. Different projections were aligned, classified, and averaged. In side view, the channel protein exhibits the shape of a truncated cone, 14 nm in height. One end has a diameter of 12 nm and is asymmetric, while the other is more symmetric and has a diameter of 7–10 nm. In top views, the sodium channel appears to consist of four domains of different size and to have a stain-filled pore in the center. 相似文献