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11.
OBJECTIVE: To evaluate the effect of a moderate dose of fish oil on glycemic control and in vivo insulin action in type 2 diabetic men with elevated plasma triacylglycerols and to determine the effect of the same treatment on gene expression of GLUT4, lipoprotein lipase (LPL), and hormone-sensitive lipase (HSL) in the abdominal adipose tissue. RESEARCH DESIGN AND METHODS: A total of 12 type 2 diabetic men were randomly allocated to 2 months of 6 g daily of either fish oil or sunflower oil, separated by a 2-month washout interval, in a double-blind crossover design. RESULTS: For glucose metabolism, 2 months of fish oil supplementation compared with sunflower oil led to similar fasting plasma insulin, glucose, and HbA1c. Basal hepatic glucose production did not increase after fish oil. There was no difference in insulin suppression of hepatic glucose production nor in insulin stimulation of whole-body glucose disposal measured by the euglycemic-hyperinsulinemic clamp. Fish oil did not ameliorate the low mRNA level of GLUT4 in adipose tissue of these patients. For lipid profile, fish oil lowered plasma triacylglycerol more than sunflower oil (P < 0.05) and tended to increase the amount of mRNA of both LPL and HSL in adipose tissue. CONCLUSIONS: A moderate dose of fish oil did not lead to deleterious effects on glycemic control or whole-body insulin sensitivity in type 2 diabetic men, with preserved triacylglycerol-lowering capacities.  相似文献   
12.
STUDY DESIGN: The present study analyzed the restriction fragment length polymorphism patterns of alpha 2(XI) collagen, bone morphogenetic protein-2, alkaline phosphatase, and tumor necrosis factor-alpha genes in patients with ossification of the posterior longitudinal ligament. This study investigates the genetic polymorphism of bone-induced factors in patients with ossification of the posterior longitudinal ligament and compares it with healthy control subjects. OBJECTIVES: To clarify the genetic markers linked to ossification of the posterior longitudinal ligament. SUMMARY OF BACKGROUND DATA: Ossification of the posterior longitudinal ligament is a genetic disease associated with abnormal calcium metabolism involving the posterior longitudinal ligament. Previous genetic studies have not identified the pathologic mechanism of ossification of the posterior longitudinal ligament. Histopathologic studies of ossification of the posterior longitudinal ligament and the animal model, the spinal hyperostotic mouse, have revealed an increase in Type XI collagen and bone morphogenetic protein-2 expression. METHODS: Eighteen Japanese patients with ossification of the posterior longitudinal ligament and 51 healthy, unrelated control subjects were investigated for the restriction fragment length polymorphism patterns of COL11A2, bone morphogenetic protein-2, alkaline phosphatase, and tumor necrosis factor-alpha, genes with various restriction endonucleases. RESULTS: The gene frequencies of COL11A2 obtained with BamHl (10.0 kb fragment) and HindIII (19.0 kb fragment) observed in patients with ossification of the posterior longitudinal ligament were higher compared with control subjects (0.43 and 0.14, respectively). These differences were statistically significant (BamHl P = 0.018; Hindlll P = 0.046). Two new restriction fragment length polymorphism patterns were detected of the bone morphogenetic protein-2 gene with Mspl and Taql and one already known restriction fragment length polymorphism pattern of the tumor necrosis factor-alpha gene with Ncol. However, they were not significantly different from the control subjects. CONCLUSIONS: Seven restriction fragment length polymorphisms of COL11A2 gene were identified. Two of them (BamHl, 10.0/10.0 kb genotype; HindIII, 19.0/19.0 kb genotype) were significantly different in patients with ossification of the posterior longitudinal ligament.  相似文献   
13.
Self-assembly of artificial peptides has been widely studied for constructing nanostructured materials, with numerous potential applications in the nanobiotechnology field. Herein, we report the synthesis and hierarchical self-assembly of collagen-mimetic peptides (CMPs) bearing various aromatic groups at the N-termini, including 2-naphthyl, 1-naphtyl, anthracenyl, and pyrenyl groups, into nanofibers. The CMPs (R-(GPO)n: n > 4) formed a triple helix structure in water at 4 °C, as confirmed via CD analyses, and their conformations were more stable with increasing hydrophobicity of the terminal aromatic group and peptide chain length. The resulting pre-organized triple helical CMPs showed diverse self-assembly into highly ordered nanofibers, reflecting their slight differences in hydrophobic/hydrophilic balance and configuration of aromatic templates. TEM analysis demonstrated that 2Np-CMPn (n = 6 and 7) and Py-CMP6 provided well-developed natural collagen-like nanofibers and An-CMPn (n = 5–7) self-assembled into rod-like micelle fibers. On the other hand, 2Np-CMP5 and 1Np-CMP6 were unable to form nanofibers under the same conditions. Furthermore, the Py-CMP6 nanofiber was found to encapsulate a guest hydrophobic molecule, Nile red, and exhibited unique emission behavior based on the specific nanostructure. In addition to the ability of CMPs to bind small molecules, their controlled self-assembly enables their versatile utilization in drug delivery and wavelength-conversion nanomaterials.  相似文献   
14.
The diamond-like carbon (DLC) multilayer films have been deposited by plasma CVD deposition onSi wafer substrate. The deposited films have then been post-annealed in vacuum at 250 °C for 2 h. Changes in internal stress, hardness, critical load, friction coefficient and wear have been investigated toassess the influence of annealing on mechanical and tribological properties of DLC multilayer films. At the same time, DLC single layerfilms are also deposited and annealed in the same method for a comparison.The results show that there is 28–33% decrease in internal stress and 10–13% decrease in hardness of theDLC single layer films after the anneal treatment. However, for the DLC multilayer films, there is 41–43% decreasein internal stress and less than 2% decrease in hardness. In addition, the annealed DLC multilayer filmhas the same friction and wear properties as that un-annealed film. This result indicates that the anneal treatment isan effective method for the DLC multilayer films to reduce the internal stress and to increase the critical load.The by-effect of the annealing, decrease of hardness and wear resistance of the multilayer film, can be restrictedby the multilayer structure.  相似文献   
15.
Some stereoblind observers do not perceive depth of 3D stimuli that depends on binocular disparity. These individuals, who have no disabilities, comprise over 5% of the general population. In addition, 17–30% of nonstereoblind young and young–middle people do not use disparity information in certain 3D environments, a phenomenon known as pseudo‐stereoblindness. This study aimed to investigate the relationship between aging and the proportion of pseudo‐stereoblindness in the general population. In an experiment, 134 nonstereoblind participants, ranging in age from 17 to 83 years, judged subjective depth of 3D stimuli containing binocular disparity and pictorial depth cues. Results showed that the proportion of pseudo‐stereoblindness among young (17–24 years old) and young–middle aged observers (25–39 years old) was 29%, in both cases. However, the proportion of pseudo‐stereoblind observers increased in older populations: 65% and 82% in the middle (40–54 years old) and senior (55–83 years old) age groups, respectively. These results suggest that a number of people, especially in elderly populations, have trouble perceiving depth from binocular disparity in 3D graphic contents despite their essential ability to use disparity information.  相似文献   
16.
Effective renaturation of reduced lysozyme by gentle removal of urea   总被引:1,自引:0,他引:1  
To increase the folding yield of concentrated reduced lysozyme,we developed a renaturation method by means of dialysis fromconcentrated urea with redox agents. After lysozyme was incubatedin the reducing buffer (8 M urea solution) with oxidized glutathione,renaturation of reduced lysozyme was started by dialysis againstthe dialyzing buffer containing 8 M urea with redox agents.The urea concentration of the dialyzing bottle was graduallydiluted with dialyzing buffer without urea at a flow rate of0.1 ml/min by high pressure pump. Using this systematic dialysis,a concentration as high as 5 mg/ml of reduced lysozyme couldbe renaturated in 80% yield, while the folding yield was <5%even at a concentration of 1 mg/ml using a conventional rapiddilution method [Goldberg et al. (1991) Biochemistry, 30, 2790–2797].Therefore, it was concluded that gentle removal of urea fromdenatured proteins, dissolved in concentrated urea solution,by means of dialysis should be useful to renature denaturedproteins effectively.  相似文献   
17.
This paper is concerned with the development of a continuous strip-casting technology to facilitate the manufacture of magnesium sheet alloys economically whilst maintaining high quality. Established in the paper is warm formability of cast magnesium alloy sheets after being hot rolled by semi-solid roll strip-casting process. It has been found that magnesium sheet with 2.0–4.0 mm thickness could be produced at a speed of 25 m/min. Hot rolling and annealing temperatures during hot rolling were also changed to examine which condition would be appropriate for producing wrought magnesium alloys with good formability. Microstructures of the crystals of the manufactured wrought magnesium alloys were observed. It has been found that a limiting drawing ratio of 2.7 was possible in a warm deep-drawing test of the cast magnesium alloy sheets after being hot rolled.  相似文献   
18.
Tree is a data structure used to express various objects such as semistructured data and genes. When objects are represented as trees, computing tree similarity is essential for pattern recognition and retrieval. This paper considers the noisy subsequence tree recognition problem whose purpose is to recognize the original tree, given its noisy subsequence tree. Previous research on this problem relied on constrained tree edit distance to measure the dissimilarity. However, the number of relabelings must be predetermined to compute it. This paper proposes a new dissimilarity measure for this problem. Our dissimilarity measure is obtained by counting the node edit operations included in the unit‐cost tree edit distance that contribute to the matching of node labels. The number of relabelings need not be specified to compute our dissimilarity measure. Moreover, our measure achieves more accurate recognition performance and faster execution speed than the constrained tree edit distance. Our measure is also useful to solve the tree inclusion problem which is the problem of deciding whether a tree includes another tree and shows the extent of approximate tree inclusion when a tree incompletely includes another tree. © 2011 Wiley Periodicals, Inc.  相似文献   
19.
In this study, we fabricated multilayer ceramics (MLCs) composed of multilayered Pb(Zr,Ti)O3 (PZT) piezoelectric thin films with internal electrodes and evaluated their dielectric and piezoelectric properties. The stack of PZT ferroelectric layers (550 nm) and SrRuO3 (SRO, 80 nm) electrodes were alternatively deposited on Pt/Ti-coated silicon-on-insulator substrates by radio-frequency magnetron sputtering. The MLCs composed of one, three, and five PZT layers were fabricated by the alternate sputtering deposition of PZT ferroelectric layers and SRO electrodes through the movable shadow mask. The capacitances of MLCs were proportionally increased with the number of PZT layers, while their relative dielectric constants were almost same among the each MLC. The MLCs exhibited symmetric and saturated PE hysteresis loops similar to the conventional PZT thin films. We estimated that the piezoelectric properties of MLCs by FEM simulation, and confirmed that the effective transverse piezoelectric coefficients (d 31,eff ) increased with the number of PZT layers. The piezoelectric coefficients calculated to be d 31,eff  = ?2964 pC/N at 25 PZT layers, which is much higher than those of conventional single-layer piezoelectric thin films.  相似文献   
20.
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