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排序方式: 共有394条查询结果,搜索用时 15 毫秒
81.
Negin Rezavand MD Saba Tabarok MD Ziba Rahimi MSc Asad Vaisi-Raygani PhD Ehsan Mohammadi MSc Zohreh Rahimi PhD 《Journal of cellular biochemistry》2019,120(4):6441-6448
We investigated the influence of vitamin D receptor (VDR) polymorphisms and vitamin D level on the blood pressure and the risk of preeclampsia. In a case-control study, 200 pregnant women, including 100 individuals with preeclampsia along with 100 healthy pregnant women, were studied for VDR FokI, TaqI, and BmsI polymorphisms and serum 25 (OH)-D level using polymerase chain reaction-restriction fragment length polymorphism method and commercial kit, respectively. The mean level of 25 (OH)-D in preeclamptic patients was significantly lower (16.6 ± 4.2 ng/mL, P < 0.001) compared with controls (19.6 ± 3.8 ng/mL). Among all women, a significantly higher systolic blood pressure and before-pregnancy body mass index and also lower gestational age were observed in the presence of 25 (OH)-D level < 20 ng/mL compared with the 20 to 30 ng/mL. A significantly higher frequency of VDR FokI C allele in preeclamptic patients (83%) than controls (74%) was associated with a 1.72-fold increased risk of preeclampsia. In all the studied individuals, the systolic and diastolic blood pressures were significantly higher in the presence of the FokI CC genotype compared with the TC and TT+TC genotypes. Neither VDR Taq1 nor VDR BmsI was associated with the risk of preeclampsia. The haplotype FokI C, TaqI C and BmsI A (CCA) compared with haplotype CTG increased the risk of preeclampsia by 1.4-fold (P = 0.33). Our study suggests an association between VDR FokI polymorphism and an insufficient serum level of 25 (OH)-D with the risk of preeclampsia and also the influence of insufficient 25 (OH)-D level and VDR FokI polymorphism on maternal factors, including blood pressure. 相似文献
82.
Peizhong Zheng MD Ali Babar Seshasai Parthasarathy Ryan Gibson Kelly Parliament Josh Flook Thomas Patterson Peter Friedemann Siva Kumpatla Steve Thompson 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(7):1537-1547
Key message
We identified a G-nucleotide insertion in a maize FatB responsible for reducing saturated fatty acids through QTL mapping and map-based cloning and developed an allele-specific DNA marker for molecular breeding.Abstract
Vegetable oils with reduced saturated fatty acids have signficant health benefits. SRS72NE, a Dow AgroSciences proprietory maize inbred line, was found to contain signficantly reduced levels of palmitic acid and total saturated fatty acids in seed oil when compared to other common inbreds. Using F2 and F3 populations derived from a cross between SRS72NE and a normal inbred SLN74, we have demonstrated that the reduced saturated fatty acid phenotype in SRS72NE is controlled by a single QTL on chromosome 9 that explains 79.1 % of palmitic acid and 79.6 % total saturated fatty acid variations. The QTL was mapped to an interval of 105 kb that contains one single gene, a type B fatty acyl-ACP thioesterase (ZmFatB; GRMZM5G829544). ZmFatB alleles from SRS72NE and common inbreds were cloned and sequenced. SRS72NE fatb allele contains a single nucleotide (G) insertion in the 6th exon, which creates a premature stop codon 22 base pairs down stream. As a result, ZmFatB protein from SRS72NE is predicted to contain eight altered and 90 deleted amino acids at its C-terminus. Because the affected region is part of the conserved acyl-ACP thioesterase catalytic domain, the truncated ZmFatB in SRS72NE is likely non-functional. We also show that fatb RNA level in SRS72NE is reduced by 4.4-fold when compared to the normal allele SNL74. A high throughput DNA assay capable of differentiating the normal and reduced saturate fatty acid alleles has been developed and can be used for accelerated molecular breeding. 相似文献83.
84.
85.
The Stomach, Helicobacter pylori, and Acid Secretion 总被引:1,自引:0,他引:1
86.
Qichen Yang MSc Vishal Jhanji MD Sze Qin Tan BSc Kwok Ping Chan BSc Di Cao PhD Wai Kit Chu DPhil Mingzhi Zhang MD Chi Pui Pang DPhil Tsz Kin Ng PhD 《Journal of cellular biochemistry》2019,120(3):4203-4213
Pterygium is a triangular-shaped hyperplastic growth, characterized by conjunctivalization, inflammation, and connective tissue remodeling. Our previous meta-analysis found that cigarette smoking is associated with a reduced risk of pterygium. Yet, the biological effect of cigarette smoke components on pterygium has not been studied. Here we reported the proliferation and migration properties of human primary pterygium cells with continuous exposure to nicotine and cotinine. Human primary pterygium cells predominantly expressed the α5, β1, and γ subunits of the nicotinic acetylcholine receptor. Continuous exposure to the mixture of 0.15 μM nicotine and 2 μM cotinine retarded pterygium cell proliferation by 16.04% (P = 0.009) and hindered their migration by 11.93% ( P = 0.039), without affecting cell apoptosis. SNAIL and α-smooth muscle actin protein expression was significantly downregulated in pterygium cells treated with 0.15 μM nicotine-2 μM cotinine mixture by 1.33- ( P = 0.036) and 1.31-fold ( P = 0.001), respectively. Besides, the 0.15 μM nicotine-2 μM cotinine mixture also reduced matrix metalloproteinase (MMP)-1 and MMP-9 expressions in pterygium cells by 1.56- ( P = 0.043) and 1.27-fold ( P = 0.012), respectively. In summary, this study revealed that continuous exposure of nicotine and cotinine inhibited human primary pterygium cell proliferation and migration in vitro by reducing epithelial-to-mesenchymal transition and MMP protein expression, partially explaining the lower incidence of pterygium in cigarette smokers. 相似文献
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88.
Mark Ming-Long Hsu MD Jen-Chyi Chang Koji Yokoyama Kazuko Nishimura Makoto Miyaji 《Mycopathologia》1994,127(2):77-81
Twenty-one strains ofCryptococcus neoformans isolated from patients in Taiwan were characterized for serotypes and mating types. Slide agglutination test was performed with 8 factor-specific sera (Iatron Company, Japan) to determine the serotypes. Wheat bran agar (WBA) and malt extract agar (MEA, Wickerham) media were used for the mating tests. Twenty of the isolates were of serotype A, and one was serotype B. Except for 2 strains of serotype A, all of the serotype A strains mated withFilobasidiella neoformans var.neoformans, mating type a. The only serotype B strain mated withF. neoformans var.bacillispora mating type a in MEA medium. These data revealed the low prevalence (1/21; 4.8%) ofC. neoformans var.gattii in Taiwan, a subtropically located island. 相似文献
89.
Expression of a constitutive form of calcium/calmodulin dependent protein kinase II leads to arrest of the cell cycle in G2. 总被引:5,自引:0,他引:5 下载免费PDF全文
Calcium/calmodulin dependent protein kinase II (CaMKII) is a multifunctional serine/threonine protein kinase. We have created a calcium/calmodulin independent form of this enzyme by truncation. Expression of this enzyme fragment in a rabbit reticulocyte lysate yields a constitutive enzyme with specific activity similar to the activated native enzyme. We have established mammalian cell lines that transiently express this constitutive enzyme using the glucocorticoid-inducible mouse mammary tumor virus long terminal repeat. The transient increase in kinase activity results in a complete cessation of cell cycle progression. This block develops as a consequence of a specific arrest of the cell cycle in G2. During the block, increases in histone H1 kinase activity present in p13 beads or anti-cdc2 immunoprecipitates are seen in parallel with the accumulation of cells at G2, arguing that the arrest is not due to a failure to activate cdc2 as a histone H1 kinase. These results suggest that other changes in serine/threonine protein phosphorylation besides those involved in activation of cdc2 as a histone H1 kinase may be necessary for proper G2-M transition. 相似文献
90.