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81.
Rodearmel SJ Wyatt HR Barry MJ Dong F Pan D Israel RG Cho SS McBurney MI Hill JO 《Obesity (Silver Spring, Md.)》2006,14(8):1392-1401
Objective: Preventing weight gain in adults and excessive weight gain in children is a high priority. We evaluated the ability of a family‐based program aimed at increasing steps and cereal consumption (for breakfast and snacks) to reduce weight gain in children and adults. Research Methods and Procedures: Families (n = 105) with at least one 8‐ to 12‐year‐old child who was at‐risk‐for‐overweight or overweight (designated as the target child) were recruited for the study. Eighty‐two families were randomly assigned to receive the family‐based intervention and 23 families to the control condition. The 13‐week intervention consisted of specific increases in daily steps (an additional 2000 steps/d) and consumption of 2 servings/d of ready‐to‐eat cereal. Results: The intervention was successful in increasing walking (steps) and cereal consumption. The intervention had positive, significant effects on percentage BMI‐for‐age and percentage body fat for target children and weight, BMI, and percentage body fat for parents. On further analysis, the positive effects of the intervention were seen largely in target girls and moms, rather than in target boys and dads. Discussion: This family‐based weight gain prevention program based on small changes holds promise for reducing excessive weight gain in families and especially in growing overweight children. 相似文献
82.
Zhang Hao Qing Zhao Xue Qiang Chen Yi Ling Zhang Ling Yu Shen Ren Fang 《Plant and Soil》2019,439(1-2):293-308
Plant and Soil - Biocrusts are important functional units in dryland ecosystems. Regarded as ecosystem engineers, cyanobacteria in biocrusts contribute several major physico-chemical and biological... 相似文献
83.
This article summarizes the current understanding of known variant forms of the MGMT gene that encode an altered protein. Epidemiological studies have been carried out to test whether these alterations are associated with altered cancer risk. Laboratory studies using recombinant proteins and cells expressing the known variants have investigated the possible effects of these sequence alterations on the ability of the encoded O(6)-alkylguanine-DNA alkyltransferase protein to protect cells from alkylation damage and to respond to therapeutic inactivators currently undergoing trials for cancer chemotherapy. 相似文献
84.
The resonant recognition model (RRM) predicts amino acid residues in highly conserved regions of the hormone prolactin (PRL) 总被引:2,自引:0,他引:2
The resonant recognition model (RRM) is a model which treats the protein sequence as a discrete signal. It has been shown previously that certain periodicities (frequencies) in this signal characterise protein biological function. The RRM was employed to determine the characteristic frequencies of the hormone prolactin (PRL), and to identify amino acids ('hot spots') mostly contributing to these frequencies and thus proposed to mostly contribute to the biological function. The predicted 'hot spot' amino acids, Phe-19, Ser-26, Ser-33, Phe-37, Phe-40, Gly-47, Gly-49, Phe-50, Ser-61, Gly-129, Arg-176, Arg-177, Cys-191 and Arg-192 are found in the highly conserved amino-terminal and C-terminus regions of PRL. Our predictions agree with previous experimentally tested residues by site-direct mutagenesis and photoaffinity labelling. 相似文献
85.
双向凝胶电泳-飞行时间质谱技术鉴定小鼠胚泡黏附时子宫内膜nm23-M2/NDPK B的表达 总被引:3,自引:0,他引:3
运用双向聚丙烯酰胺凝胶电泳(2DPAGE)分析未交配小鼠子宫内膜和妊娠第五天(D5)小鼠子宫内膜胚泡黏附时植入位点及其旁组织蛋白质组。差异蛋白质组学显示,等电点(isoelectric point,pI)约7.1、分子量(molecular weight,Mw)约18kDa的蛋白质点在D5小鼠子宫内膜特别是植入位点表达上调。对此蛋白质点用基质辅助激光解析电离飞行时间质谱(matrix-assisted laser desorption/ionization time of flying mass spectrometry,MALDI—TOF—MS)测定其胶内酶解后的肽质量指纹谱(Peptide Mass Fingerprint,PMF),经Mascot:Peptide Mass Fingerprint中SWISS-PROT数据库查询后,鉴定该蛋白质为鼠源性nm23-M2/NDPKB。RT—PCR和免疫组织化学结果也显示D5小鼠子宫内膜nm23-M2/NDPK B mRNA和蛋白表达明显增加。提示nm23-M2/NDPKB参与胚泡着床这一重要生命活动过程。 相似文献
86.
间隙连接蛋白 31 (connexin31 , Cx31) 是间隙连接蛋白 (connexin) 家族的一员,目前对于 Cx31 的功能及其调节方式知之甚少 . 采用固相多肽合成的方法合成 Cx31 羧基端一个多肽片段 (250~266) ,经 HPLC 纯化后偶联到匙孔血蓝蛋白,免疫新西兰雄兔后采血检测、并纯化、经蛋白质印迹、细胞免疫荧光染色、免疫沉淀证实得到的抗体为特异性抗 Cx31 的抗体 . 运用制备的抗 Cx31 多克隆抗体免疫沉淀, SDS- 聚丙烯酰胺凝胶电泳 (SDS-PAGE) 分离,蛋白质条带回收,蛋白质胶块酶解, Q-TOF 质谱分析,数据库扫描筛选可能相互作用蛋白,运用抗体 pull-down 实验,筛选到可能相互作用蛋白 annexin Ⅱ,经过免疫共沉淀、细胞免疫共定位等实验证实 annexin Ⅱ与 Cx31 相互作用 . 相似文献
87.
88.
Linsheng Liu Jiye Aa Guangji Wang Bei Yan Xinwen Wang Bei Cao Mengjie Li Yuanting Zheng Fang Zhou Zimei Wu 《Analytical biochemistry》2010,406(2):105-6697
In metabolomic research, blood plasma and serum have been considered to possess similar compositions and properties. Their perceived equivalence has resulted in researchers choosing arbitrarily between serum and plasma for analysis. Here, routine serum and plasma were prepared and their low-molecular-weight compounds were determined using gas chromatography/time-of-flight mass spectrometry. Principal components analysis was applied to process the acquired data, and marked differences in metabolite profiles were observed between serum and plasma. Of the 72 identified compounds, 36 (50%) discriminate serum from plasma, with 29 and 7 metabolites showing a significantly higher abundance (t test, P < 0.05) in serum and plasma, respectively. Incubation of blood had distinct effects on the analyte peak areas, with the effects being more pronounced for plasma than for serum and more pronounced for a shorter incubation than for a longer incubation. These results highlight the importance in choosing serum or plasma as the analytical sample and in stipulating the incubation time. Because incubation affected the analyte peak areas less in serum than in plasma, we recommend serum as the sample of choice in metabolomic studies. 相似文献
89.
90.
The chemiluminescence immunoassay for aflatoxin B1 based on functionalized magnetic nanoparticles with two strategies of antigen probe immobilization 下载免费PDF全文
A rapid and sensitive chemiluminescence immunoassay (CLIA) based on magnetic nanoparticles (MNPs) was developed to detect aflatoxin B1 (AFB1), which is a potent carcinogen in nature. We prepared monodisperse MNPs (300 nm in diameter) according to the solvothermal synthesis reaction and the MNPs were coated with silica by the Stöber method. Triethox was used as a one‐step carboxylation reagent, and 3‐aminopropyltriethoxysilane (APTES) an amination reagent, to modify the MNPs. We prepared two types of solid phase antigens using the above synthesized functionalized MNPs coupled with the later prepared AFB1‐oxime active ester and the purchased BSA–AFB1 respectively. 2′,6′‐dimethylcarbonylphenyl‐10‐sulfopropylacridinium‐9‐carboxylate 4′‐N‐hydroxysuccinimide (4′‐NHS) ester (NSP–DMAE–NHS), as a novel luminescent reagent, was used to label anti‐AFB1 antibodies. The two CLIA calibration curves based on the two types of solid phase antigens were obtained and compared. The acquired limit of detection (LOD) was about 0.001 ng/mL for the two functionalized MNPs‐based immunoassays, and the half maximal inhibitory concentration (IC50) was 0.51 ng/mL for the MNPs–AFB1‐based method and 0.72 ng/mL for the MNPs–BSA–AFB1‐based method. 相似文献