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排序方式: 共有1214条查询结果,搜索用时 803 毫秒
271.
Sekikawa A Steingrimsdottir L Ueshima H Shin C Curb JD Evans RW Hauksdottir AM Kadota A Choo J Masaki K Thorsson B Launer LJ Garcia ME Maegawa H Willcox BJ Eiriksdottir G Fujiyoshi A Miura K Harris TB Kuller LH Gudnason V 《Prostaglandins, leukotrienes, and essential fatty acids》2012,87(1):11-16
In the 1990s Iceland and Japan were known as countries with high fish consumption whereas coronary heart disease (CHD) mortality in Iceland was high and that in Japan was low among developed countries. We described recent data fish consumption and CHD mortality from publicly available data. We also measured CHD risk factors and serum levels of marine-derived n-3 and other fatty acids from population-based samples of 1324 men in Iceland, Japan, South Korea, and the US. CHD mortality in men in Iceland was almost 3 times as high as that in Japan and South Korea. Generally, a profile of CHD risk factors in Icelanders compared to Japanese was more favorable. Serum marine-derived n-3 fatty acids in Iceland were significantly lower than in Japan and South Korea but significantly higher than in the US. 相似文献
272.
Higashi TL Ikeda M Tanaka H Nakagawa T Bando M Shirahige K Kubota Y Takisawa H Masukata H Takahashi TS 《Current biology : CB》2012,22(11):977-988
Highlights? XEco2 loading and cohesin acetylation require pre-RC assembly but not DNA synthesis ? Two N-terminal motifs in XEco2 are essential for XEco2 loading and cohesion ? The PIP box in XEco2 contributes to cohesion ? Interaction of acetylated cohesin with DNA is stabilized after DNA replication 相似文献
273.
Seto S Yumoto K Okada K Asahina Y Iwane A Iwago M Terasawa R Shreder KR Murakami K Kohno Y 《Bioorganic & medicinal chemistry》2012,20(3):1188-1200
The design, synthesis, and evaluation of 6-6-7 tricyclic quinolones containing the strained spirocycle moiety aiming at the GSK-3β inhibitor were described. Among the synthesized compounds, 44, having a cyclobutane ring on a spirocycle, showed excellent GSK-3β inhibitory activity in both cell-free and cell-based assays (IC(50) = 36nM, EC(50) = 3.2μM, respectively). Additionally, 44 decreased the plasma glucose concentration dose-dependently after an oral glucose tolerance test in mice. 相似文献
274.
Kageyama K Akimoto K Yamagata S Sugiyama A Murasawa S Watanuki Y Tamasawa N Suda T 《Regulatory peptides》2012,174(1-3):12-17
Growth hormone (GH)-releasing peptides (GHRPs) are synthetic peptides that strongly induce GH release. GHRPs act via a specific receptor, the GHRP receptor (GHSR), of which ghrelin is a natural ligand. GHRPs also induce adrenocorticotropic hormone (ACTH) release in healthy subjects. GHRPs or ghrelin stimulate ACTH release via corticotropin-releasing factor (CRF) and arginin vasopressin in the hypothalamus. Stress-activated CRF neurons are suppressed by glucocorticoids in the hypothalamic paraventricular nucleus (PVN), while CRF gene is up-regulated by glucocorticoids in the PVN cells without the influence of input neurons. However, little is known about the regulation of ghrelin and GHSR type 1a (GHSR1a) genes by glucocorticoids in PVN cells. To elucidate the regulation of ghrelin and GHSR gene expression by glucocorticoids in PVN cells, here we used a homologous PVN neuronal cell line, hypothalamic 4B, because these cells show characteristics of the parvocellular neurons of the PVN. These cells also express ghrelin and GHSR1a mRNA. Dexamethasone increased ghrelin mRNA levels. A potent glucocorticoid receptor antagonist, RU-486, significantly blocked dexamethasone-induced increases in ghrelin mRNA levels. Dexamethasone also significantly stimulated GHSR1a mRNA and protein levels. Finally, ghrelin increased CRF mRNA levels, as did dexamethasone. Incubation with both dexamethasone and ghrelin had an additive effect on CRF and ghrelin mRNA levels. The ghrelin-GHSR1a system is activated by glucocorticoids in the hypothalamic cells. 相似文献
275.
Morisaka H Kirino A Kobayashi K Ueda M 《Bioscience, biotechnology, and biochemistry》2012,76(3):585-588
A two-dimensional high-performance liquid chromatography (2D-HPLC) system for protein separation was developed using an ion-exchange column in the first dimension and a reversed-phase monolithic column in the second dimension. The system demonstrated efficient separation of proteins in comparison with conventional systems. For proteomic analysis, proteins extracted from the cell surface of the yeast were separated by 2D-HPLC and evaluated. 相似文献
276.
277.
Sayama T Ono E Takagi K Takada Y Horikawa M Nakamoto Y Hirose A Sasama H Ohashi M Hasegawa H Terakawa T Kikuchi A Kato S Tatsuzaki N Tsukamoto C Ishimoto M 《The Plant cell》2012,24(5):2123-2138
Triterpene saponins are a diverse group of biologically functional products in plants. Saponins usually are glycosylated, which gives rise to a wide diversity of structures and functions. In the group A saponins of soybean (Glycine max), differences in the terminal sugar species located on the C-22 sugar chain of an aglycone core, soyasapogenol A, were observed to be under genetic control. Further genetic analyses and mapping revealed that the structural diversity of glycosylation was determined by multiple alleles of a single locus, Sg-1, and led to identification of a UDP-sugar-dependent glycosyltransferase gene (Glyma07g38460). Although their sequences are highly similar and both glycosylate the nonacetylated saponin A0-αg, the Sg-1(a) allele encodes the xylosyltransferase UGT73F4, whereas Sg-1(b) encodes the glucosyltransferase UGT73F2. Homology models and site-directed mutagenesis analyses showed that Ser-138 in Sg-1(a) and Gly-138 in Sg-1(b) proteins are crucial residues for their respective sugar donor specificities. Transgenic complementation tests followed by recombinant enzyme assays in vitro demonstrated that sg-1(0) is a loss-of-function allele of Sg-1. Considering that the terminal sugar species in the group A saponins are responsible for the strong bitterness and astringent aftertastes of soybean seeds, our findings herein provide useful tools to improve commercial properties of soybean products. 相似文献
278.
Sexual selection often favors male secondary sexual traits, although in some cases the elaborate traits incur costs to the males with respect to natural selection. Males of the guppy Poecilia reticulata have longer tails (caudal fins) than females, and the long tails contribute to the mating success of the males through female mate choice. We examined the effect of tail length on the swimming performance of male and female guppies. In a laboratory experiment, males with longer tails exhibited poorer swimming performance than those with shorter tails. However, this effect was not apparent in females. In addition, in a feral population, tail length of males was negatively correlated with water flow velocity in their microhabitats. Although body size of females was negatively correlated with water flow velocity in their microhabitats, tail length of females showed no significant correlation with degree of water flow. These results suggest that the long tail of male guppies incurs costs, such as a decrease in swimming performance, to the males with respect to natural selection and consequently limits their choice of habitats to those with slow water flow. 相似文献
279.
Paul-Prasanth B Matsuda M Lau EL Suzuki A Sakai F Kobayashi T Nagahama Y 《Biochemical and biophysical research communications》2006,351(4):815-819
DMY is the second vertebrate sex-determining gene identified from the fish, Oryzias latipes. In this study, we used two different ways of sex reversal, DMY knock-down and estradiol-17beta (E2) treatment, to determine the possible function of DMY during early gonadal sex differentiation in XY medaka. Our findings revealed that the mitotic and meiotic activities of the germ cells in the 0 day after hatching (dah) DMY knock-down XY larvae were identical to those of the normal XX larvae, suggesting the microenvironment of these XY gonads to be similar to that of the normal XX gonad, where DMY is naturally absent. Conversely, E2 treatment failed to initiate mitosis in the XY gonad, possibly due to an active DMY, even though it could initiate meiosis. Present study is the first to prove that the germ cells in the XY gonad can resume the mitotic activity, if DMY was knocked down. 相似文献
280.
Koizumi T Bando N Terao J Yamanishi R 《Bioscience, biotechnology, and biochemistry》2006,70(12):3042-3045
beta-Carotene and/or supplemental alpha-tocopherol were fed to DO11.10 mice to investigate their effect on the immune function of naive splenocytes. A high secretion of interleukin-12 and interferon-gamma in response to the ex vivo primary antigen presentation occurred only when both were fed. This is consistent with the suppressed immunoglobulin E production under the similar condition described in our previous report. 相似文献