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排序方式: 共有277条查询结果,搜索用时 187 毫秒
51.
52.
Mechanisms Underlying Decreased Hepatic Triacylglycerol and Cholesterol by Dietary Bitter Melon Extract in the Rat 总被引:4,自引:0,他引:4
Senanayake GV Fukuda N Nshizono S Wang YM Nagao K Yanagita T Iwamoto M Ohta H 《Lipids》2012,47(5):495-503
In these studies, we focused on finding the mechanism(s) underlying the bitter melon (Momordica charantia L.) methanol fraction (MF)-dependent reduction in the concentration of hepatic triacylglycerol (TAG) and cholesterol in the
rat. Rats were fed diets containing low (5 %) fat for 2 weeks (experiment 1), or low (5 %) and high (15 %) fat for a longer
period of 8 weeks (experiment 2). MF was supplemented at 1 % level in both experiments. After feeding, rats were sacrificed,
and their livers were prepared as slices and hepatocytes, followed by incubation with [1(2)-14C] acetate or [1-14C] oleic acid (18:1 n-6). Under these conditions, we found that rats fed diets containing MF, as compared to those without
MF, showed: (1) no adverse effects on food intake and growth, (2) a decreased hepatic TAG and total cholesterol, irrespective
of the difference in dietary fat level or feeding period, and (3) a decreased incorporation of [1(2)-14C] acetate and [1-14C] oleic acid into TAG of liver slices and hepatocytes. MF-supplemented rats also showed no altered incorporation of labeled
acetate into cholesterol and cholesterol ester, an increased fecal excretion of neutral steroids, but not of acidic steroids,
and an enhanced mRNA abundance of carnitine palmitoylacyltransferase I, which is the rate-limiting enzyme for fatty acid oxidation.
These results suggest that dietary MF decreases hepatic TAG synthesis while enhancing fatty acid oxidation, thereby reducing
the concentration of hepatic TAG. The liver cholesterol-lowering effect of MF, however, is probably mediated through an increased
fecal excretion of neutral steroids, without an effect on cholesterogenesis. 相似文献
53.
We examined the effects of D- or L-amino acids on the stimulation of Brassica rapa roots. When 6.7 microM of D-methionine (D-Met) or L-methionine (L-Met) was applied, root hair numbers increased. L-Met (above concentration of 67.0 microM) caused the tip of roots to spiral. When CoCl2 (ethylene synthesis inhibitor) was added into the medium, L-Met lost its activity but COCl2 did not inhibit the bioactivity of D-Met. 相似文献
54.
Yohei Iizawa Soichiro Araki Shinya Ishida Itaru Nishioka Kohei Shimada Hiroshi Hasegawa Ken-ichi Sato 《Optical Switching and Networking》2013,10(1):32-43
We discuss issues for controlling an optical path in large-scale photonic networks, and introduce an inter-domain path control system based on Path Computation Elements (PCEs). In the system, maximum flow information enables the load balancing of traffic, and Path Key scheme preserve the confidentiality of internal topology information among carrier networks. Based on the experimental results, we show the path setup in the introduced system is significantly faster than the manual path setup among domains in current carriers' networks. For the additional reduction of the path setup time, we propose the domain-wise paralleled signaling method. We also show that decreasing the number of nodes per domain makes path setup faster in the introduced system with deployment of the proposed signaling method. 相似文献
55.
56.
Takahiro Kochi Masahito Shimizu Tomohiko Ohno Atsushi Baba Takafumi Sumi Masaya Kubota Yohei Shirakami Hisashi Tsurumi Takuji Tanaka Hisataka Moriwaki 《International journal of molecular sciences》2013,14(7):14700-14711
Metabolic syndrome is associated with an increased risk of colorectal cancer. This study investigated the impact of hypertension, a component of metabolic syndrome, on azoxymethane (AOM)-induced colorectal carcinogenesis using SHRSP/Izm (SHRSP) non-diabetic/hypertensive rats and SHRSP.Z-Leprfa/IzmDmcr (SHRSP-ZF) diabetic/hypertensive rats. Male 6-week-old SHRSP, SHRSP-ZF, and control non-diabetic/normotensive Wister Kyoto/Izm (WKY) rats were given 2 weekly intraperitoneal injections of AOM (20 mg/kg body weight). Two weeks after the last injection of AOM, the SHRSP and SHRSP-ZF rats became hypertensive compared to the control WKY rats. Serum levels of angiotensin-II, the active product of the renin-angiotensin system, were elevated in both SHRSP and SHRSP-ZF rats, but only the SHRSP-ZF rats developed insulin resistance, dyslipidemia, and hyperleptinemia and exhibited an increase in adipose tissue. The development of AOM-induced colonic preneoplastic lesions and aberrant crypts foci, was significantly accelerated in both SHRSP and SHRSP-ZF hypertensive rats, compared to WKY normotensive rats. Furthermore, induction of oxidative stress and exacerbation of inflammation were observed in the colonic mucosa and systemically in SHRSP and SHRSP-ZF rats. Our findings suggest that hypertension plays a role in the early stage of colorectal carcinogenesis by inducing oxidative stress and chronic inflammation, which might be associated with activation of the renin-angiotensin system. 相似文献
57.
Takeshi Terayama Susumu Nagata Yohei Tanaka Akihiko Momma Tohru Kato Masaru Kunii Atsushi Yamamoto 《Journal of Electronic Materials》2013,42(7):2306-2313
Solid oxide fuel cells (SOFCs) are being researched around the world. In Japan, a compact SOFC system with rated alternative current (AC) power of 700 W has become available on the market, since the base load electricity demand for a standard home is said to be less than 700 W AC. To improve the generating efficiency of SOFC systems in the 700-W class, we focused on thermoelectric generation (TEG) technology, since there are a lot of temperature gradients in the system. Analysis based on simulations indicated the possibility of introducing thermoelectric generation at the air preheater, steam generator, and exhaust outlet. Among these options, incorporating a TEG heat exchanger comprising multiple CoSb3/SiGe-based TEG modules into the air preheater had potential to produce additional output of 37.5 W and an improvement in generating efficiency from 46% to 48.5%. Furthermore, by introducing thermoelectric generation at the other two locations, an increase in maximum output of more than 50 W and generating efficiency of 50% can be anticipated. 相似文献
58.
Yuya Kano Yohei Kayukawa Kenichi Fujii Haruki Sato 《International Journal of Thermophysics》2010,31(11-12):2051-2058
The isobaric ideal-gas heat capacity for HFO-1234yf, which is expected to be one of the best alternative refrigerants for HFC-134a, was determined on the basis of speed-of-sound measurements in the gaseous phase. The speed of sound was measured by means of the acoustic resonance method using a spherical cavity. The resonance frequency in the spherical cavity containing the sample gas was measured to determine the speed of sound. After correcting for some effects such as the thermal boundary layer and deformation of the cavity on the resonance frequency, the speed of sound was obtained with a relative uncertainty of 0.01 %. Using the measured speed-of-sound data, the acoustic-virial equation was formulated and the isobaric ideal-gas heat capacity was determined with a relative uncertainty of 0.1 %. A temperature correlation function of the isobaric ideal-gas heat capacity for HFO-1234yf was also developed. 相似文献
59.
Keisuke Ohdaira Kazuhiro Shiba Hiroyuki Takemoto Tomoko Fujiwara Yohei Endo Shogo Nishizaki Young Rae Jang Hideki Matsumura 《Thin solid films》2009,517(12):3472-4461
Amorphous Si (a-Si) films with lower hydrogen contents show better adhesion to glass during flash lamp annealing (FLA). The 2.0 µm-thick a-Si films deposited by plasma-enhanced chemical vapor deposition (PECVD), containing 10% hydrogen, start to peel off even at a lamp irradiance lower than that required for crystallization, whereas a-Si films deposited by catalytic CVD (Cat-CVD) partially adhere even after crystallization. Dehydrogenated Cat-CVD a-Si films show much better adhesion to glass, and are converted to polycrystalline Si (poly-Si) without serious peeling, but are accompanied by the generation of crack-like structures. These facts demonstrate the superiority of as-deposited Cat-CVD a-Si films as a precursor material for micrometer-thick poly-Si formed by FLA. 相似文献
60.
Haruhiko Ohya Svetlana I. Semenova Aya Sawada Shinichi Fukaya Yohei Suzuki Masahako Aihara Youichi Negishi 《Desalination》2001,140(3):42-245
A relation was obtained between electro-chemical properties of sodium salts (NaCl, NaBr, and Na2SO4), and the thermodynamic property of permeability in symmetrical cellulose acetate membranes, the distribution coefficient K and the kinetic property, the overall diffusion coefficients D. K and D were obtained by the method we proposed using measured unsteady- and steady-state dialysis data. The K values increase with the increase of water content and are in the range of 10−2 for sodium halides and 10−3 for Na2SO4. D is found to increase with the increase of the solute concentration, and the extrapolated values of D to zero concentration D(0) are obtained as 0.015–0.03 μm2/s and increase with the increase of water content in the membrane. D can be divided into the concentration independent diffusion coefficients in the dense part of the membrane Dd and in the porous Dp, applying a two-part (perfect or dense and imperfect or porous) model of the membrane. Contrary to Dd, Dp increases with the increase of Ww and can be correlated as Dp,c =
d exp (γ × Ww). It is shown that the averaged Dd,
D increases with the increase of the quantity of the ionic mobility u of the solutes at infinite dilution divided by valence, and that the parameter γ increases with the increase of the ionic mobility u. The value of K increases slightly with the increase of water content and decreases with the increase of the Flory—Huggins parameter χ. The Flory—Huggins parameter χ is calculated from the measured values of distribution coefficients and data obtained from the literature. And it was found that the gradient of linear decrease of χ (λcation) depends on equivalent ionic conductivity of anion of salt, λan. 相似文献