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排序方式: 共有742条查询结果,搜索用时 15 毫秒
251.
Michiya Ohno Fumiko Deguchi Kumiko Izumi Hirotoshi Ishigaki Hiroshi Sarui Akihiko Sasaki Tomonori Segawa Takahiko Yamaki Takao Kojima Hiroshige Ohashi 《PloS one》2014,9(11)
Background/Aims
Age, proteinuria, metabolic syndrome, and hyperuricemia are the reported risk factors for chronic kidney disease (CKD) and cardiovascular disease (CVD). However, the best predictor of changes in renal function in the early stages of renal disease in a healthy middle-aged population is still unknown. Our study evaluated the correlation between changes in renal function and common risk factors to determine such a predictor.Methods
In total, 2,853 healthy persons aged ≤50 years participated in the study. They had no proteinuria and were not on medications for hypertension, diabetes mellitus, hyperlipidemia, or hyperuricemia. Over 2 years, participants underwent annual health screening. The relationship between changes in estimated glomerular filtration rate (eGFR) and changes in risk factors for CKD was evaluated using univariate and multivariate linear regression analyses.Results
Over 2 years, eGFR showed a significant decrease. Univariate regression analysis revealed that changes in fasting plasma glucose (FPG), total cholesterol, LDL-cholesterol, serum uric acid levels, and hemoglobin showed a significant negative correlation with changes in eGFR. Multiple regression analysis confirmed that changes in FPG, serum uric acid levels, in particular, and hemoglobin had a significant negative correlation with changes in eGFR.Conclusion
The changes in eGFR and other variables over 2 years were small and could be within expected biologic variation. A longer observational study is needed to elucidate whether FPG, serum uric acid and hemoglobin represent the earliest markers of eGFR decline. 相似文献252.
Róg T Murzyn K Gurbiel R Takaoka Y Kusumi A Pasenkiewicz-Gierula M 《Journal of lipid research》2004,45(2):326-336
Molecular dynamics simulations of two monounsaturated phosphatidylcholine (PC) bilayers made of 1-palmitoyl-2-oleoyl-PC (POPC; cis-unsaturated) and 1-palmitoyl-2-elaidoyl-PC (PEPC; trans-unsaturated) were carried out to investigate the effect of a double bond in the PC beta-chain and its conformation on the bilayer core. Four nanosecond trajectories were used for analyses. A fully saturated 1,2-dimyristoyl-PC (DMPC) bilayer was used as a reference system. In agreement with experimental data, this study shows that properties of the PEPC bilayer are more similar to those of the DMPC than to the POPC bilayer. The differences between POPC and PEPC bilayers may be attributed to the different ranges of angles covered by the torsion angles beta10 and beta12 of the single bonds next to the double bond in the oleoyl (O) and elaidoyl (E) chains. Broader distributions of beta10 and beta12 in the E chain than in the O chain make the E chain more flexible. In effect, the packing of chains in the PEPC bilayer is similar to that in the DMPC bilayer, whereas that in the POPC bilayer is looser than that in the DMPC bilayer. The effect of the cis-double bond on torsions at the beginning of the O chain (beta4 and beta5) is similar to that of cholesterol on these torsions in a myristoyl chain. 相似文献
253.
Inagaki M Jyoyama H Ono T Yamada K Kobayashi M Baba T Touchi A Iwatani K Ohkawa T Matsumoto S Tsuri T 《Bioorganic & medicinal chemistry》2003,11(11):2415-2419
We have synthesized and characterized some oxidative metabolites of S-2474. In this study, we discovered a novel skeleton, the 2,3-dihydrobenzofuran derivative, which inhibited PGE(2) production at a very low concentration and was effective in the anti-carrageenin footpad edema assay. 相似文献
254.
255.
Major patterns of higher teleostean phylogenies: a new perspective based on 100 complete mitochondrial DNA sequences 总被引:28,自引:0,他引:28
Miya M Takeshima H Endo H Ishiguro NB Inoue JG Mukai T Satoh TP Yamaguchi M Kawaguchi A Mabuchi K Shirai SM Nishida M 《Molecular phylogenetics and evolution》2003,26(1):121-138
A recent preliminary study using complete mitochondrial DNA sequences from 48 species of teleosts has suggested that higher teleostean phylogenies should be reinvestigated on the basis of more intensive taxonomic sampling. As a second step towards the resolution of higher teleostean phylogenies, which have been described as the "(unresolved) bush at the top of the tree," we reanalyzed their relationships using mitogenomic data from 100 purposefully chosen species that fully represented all of the higher teleostean orders, except for the Batrachoidiformes. Unweighted and weighted maximum parsimony analyses were conducted with the data set that comprised concatenated nucleotide sequences from 12 protein-coding genes (excluding 3rd codon positions) and 21 transfer RNA (tRNA) genes (stem regions only) from each species. The resultant trees were well resolved and largely congruent, with most internal branches being supported by high statistical values. All major, comprehensive groups above ordinal level as currently defined in higher teleosts (with the exception of the Neoteleostei and several monotypic groups), such as the Eurypterygii, Ctenosquamata, Acanthomorpha, Paracanthopterygii, Acanthopterygii, and Percomorpha, appeared to be nonmonophyletic in the present tree. Such incongruities largely resulted from differences in the placement and/or limits of the orders Ateleopodiformes, Lampridiformes, Polymixiiformes, Ophidiiformes, Lophiiformes, Beryciformes, Stephanoberyciformes, and Zeiformes, long-standing problematic taxa in systematic ichthyology. Of these, the resulting phylogenetic positions of the Ophidiiformes and Lophiiformes were totally unexpected, because, although they have consistently been considered relatively primitive groups within higher teleosts (Paracanthopterygii), they were confidently placed within a crown group of teleosts, herein called the Percomorpha. It should be noted that many unexpected, but highly supported relationships were found within the Percomorpha, being highly promising for the next investigative step towards resolution of this remarkably diversified group of teleosts. 相似文献
256.
Okada Y Shimane K Kochi Y Tahira T Suzuki A Higasa K Takahashi A Horita T Atsumi T Ishii T Okamoto A Fujio K Hirakata M Amano H Kondo Y Ito S Takada K Mimori A Saito K Kamachi M Kawaguchi Y Ikari K Mohammed OW Matsuda K Terao C Ohmura K Myouzen K Hosono N Tsunoda T Nishimoto N Mimori T Matsuda F Tanaka Y Sumida T Yamanaka H Takasaki Y Koike T Horiuchi T Hayashi K Kubo M Kamatani N Yamada R Nakamura Y Yamamoto K 《PLoS genetics》2012,8(1):e1002455
257.
The six-layered neocortex permits complex information processing in all mammalian species. Because its homologous region (the pallium) in nonmammalian amniotes has a different architecture, the ability of neocortical progenitors to generate an orderly sequence of distinct cell types was thought to have arisen in the mammalian lineage. This study, however, shows that layer-specific neuron subtypes do exist in the chick pallium. Deep- and upper-layer neurons are not layered but are segregated in distinct mediolateral domains in vivo. Surprisingly, cultured chick neural progenitors produce multiple layer-specific neuronal subtypes in the same chronological sequence as seen in mammals. These results suggest that the temporal sequence of the neocortical neurogenetic program was already inherent in the last common ancestor of mammals and birds and that mammals use this conserved program to generate a uniformly layered neocortex, whereas birds impose spatial constraints on the sequence to pattern the pallium. 相似文献
258.
Doekele G. Stavenga Hein L. Leertouwer Takahiko Hariyama Hans A. De Raedt Bodo D. Wilts 《PloS one》2012,7(11)
Mature male Calopteryx japonica damselflies have dark-blue wings, due to darkly coloured wing membranes and blue reflecting veins. The membranes contain a high melanin concentration and the veins have a multilayer of melanin and chitin. Female and immature C. japonica damselflies have brown wings. We have determined the refractive index of melanin by comparing the differently pigmented wing membranes and applying Jamin-Lebedeff interference microscopy. Together with the previously measured refractive index of chitin the blue, structural colour of the male wing veins could be quantitatively explained by an optical multilayer model. The obtained melanin refractive index data will be useful in optical studies on melanized tissues, especially where melanin is concentrated in layers, thus causing iridescence. 相似文献
259.
Sarcopenia is a geriatric syndrome in which there is a decrease of muscle mass and strength with aging. In age-related loss
of muscle strength, there are numerous observations supporting the assertion that neural factors mediate muscle strength.
A possible contributing cause may be that aging changes systemic extracellular heat shock protein (eHsp)72 activity. The present
study was designed to assess the plasma levels of eHsp72 in elderly people and to investigate its potential interaction with
components of sarcopenia. A total of 665 men and women participated in an official medical health examination and an integrated
health examination, including psychological and physical fitness tests. Blood samples were assayed for levels of plasma Hsp72,
serum C-reactive protein, interleukin 6, tumor necrosis factor α, and regular biomedical parameters. We found that higher
Hsp72 in plasma is associated with lower muscle mass, weaker grip strength, and slower walking speed, and may be a potential
biomarker of sarcopenia in elderly people. This finding was supported by other results in the present study: (1) older age
and shrinking body and lower hemoglobin levels, all of which characterize sarcopenia, were related to higher eHsp72 tertiles
and (2) the ORs of the highest tertile of eHsp72 for the lowest tertiles of muscle mass, grip strength, and walking speed
were 2.7, 2.6, and 1.8, respectively. These ORs were independent of age, sex, and the incidence of related diseases. Our results
would reveal that eHsp72 in plasma is linked to sarcopenia factors and is a potential biomarker or predictor of sarcopenia. 相似文献
260.
Lustgarten MS Bhattacharya A Muller FL Jang YC Shimizu T Shirasawa T Richardson A Van Remmen H 《Biochemical and biophysical research communications》2012,422(3):515-521
Mitochondrial complex I has previously been shown to release superoxide exclusively towards the mitochondrial matrix, whereas complex III releases superoxide to both the matrix and the cytosol. Superoxide produced at complex III has been shown to exit the mitochondria through voltage dependent anion channels (VDAC). To test whether complex I-derived, mitochondrial matrix-directed superoxide can be released to the cytosol, we measured superoxide generation in mitochondria isolated from wild type and from mice genetically altered to be deficient in MnSOD activity (TnIFastCreSod2(fl/fl)). Under experimental conditions that produce superoxide primarily by complex I (glutamate/malate plus rotenone, GM+R), MnSOD-deficient mitochondria release ~4-fold more superoxide than mitochondria isolated from wild type mice. Exogenous CuZnSOD completely abolished the EPR-derived GM+R signal in mitochondria isolated from both genotypes, evidence that confirms mitochondrial superoxide release. Addition of the VDAC inhibitor DIDS significantly reduced mitochondrial superoxide release (~75%) in mitochondria from either genotype respiring on GM+R. Conversely, inhibition of potential inner membrane sites of superoxide exit, including the matrix face of the mitochondrial permeability transition pore and the inner membrane anion channel did not reduce mitochondrial superoxide release in the presence of GM+R in mitochondria isolated from either genotype. These data support the concept that complex I-derived mitochondrial superoxide release does indeed occur and that the majority of this release occurs through VDACs. 相似文献