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51.
J Matsumoto H Ogawa R Maeyama K Okudaira T Shinka T Kuhara I Matsumoto 《Canadian Metallurgical Quarterly》1997,38(8):950-953
PURPOSE: We evaluated the efficacy of direct hemoperfusion (DHP) for treatment of acute valproate (VPA) intoxication and speculate on the biochemical perturbations that suggest a mechanism of coma induced by VPA overdose. PATIENT AND METHODS: The comatose patient was hospitalized approximately 6 h after ingesting 18 g VPA. DHP, with 200 g activated charcoal, was performed for 6 h. The plasma concentrations of VPA and Glasgow coma scale scores after admission were estimated. Before and after DHP, urine samples were tested in serial fashion for VPA metabolites, organic acids, and acyl carnitine esters of fatty acids. RESULTS: Plasma VPA was efficiently adsorbed on activated charcoal. The patient's plasma concentration of VPA decreased from 471 microg/ml (2,830 microM) to 45 microg/ml (270 microM), at which point the patient became alert. The half-life (t1/2) of VPA was calculated as 4.4 h before DHP and as 1.8 h during DHP. Before DHP, lactate and VPA-glucuronide markedly increased in urine samples, but beta-keto-VPA, a major mitochondrial metabolite, was not detected. Urinary excretion of carnitine esters of medium chain (C8-C10) dicarboxylic acids was increased. After DHP, lactate and VPA-glucuronide decreased, but a significant amount of beta-keto-VPA was demonstrated. Carnitine esters of medium chain dicarboxylic acids were decreased. CONCLUSIONS: DHP with activated charcoal was effective treatment for the patient with acute VPA intoxication and coma. The onset of coma may have been related to inhibition of beta-oxidation in the mitochondria, which was reversible by elimination of plasma VPA by DHP. 相似文献
52.
The in situ calibration method for the impurity influx monitor (divertor) is experimentally examined. The total reflectance of the optical path from the focal point of the Cassegrain telescope to the first mirror is derived using a micro retroreflector array. An optical fiber with angled physical contact (APC) connectors reduces the return edge reflection. APC fibers and a multimode coupler increase the signal-to-noise ratio by about one order compared to that of triple-branched fibers and enable measurement of the wavelength dependence of the total reflectance of the optical system even after potential deterioration of mirror surfaces reduces reflectance. 相似文献
53.
One-pot polymerization of polyimide from 3,3′,4,4′-biphenyl tetracarboxylic dianhydride (BPDA) and 4,4′-oxydianiline (ODA) was examined. The equilibrium in the polyimide with water was examined in detail in p-chlorophenol solution during the polymerization. The equilibrium constant was expressed by log K = 1.50 + 1433 (1/T). The polymerization reaction is exothermic. The molecular weight increased with decrease of temperature. © 1996 John Wiley & Sons, Inc. 相似文献
54.
Simultaneous extraction by microwave-irradiation and crystallisation were performed in the same pot of solvent of 70% (v/v) aqueous ethanol for isolation of hesperidin from thinned immature fruit peels of Citrus unshiu as refining of Citrus waste biomass. The hesperidin content in immature fruits peels was about 3.2-fold higher than that of mature fruit. After microwave-assisted extraction (MAE), the yield of hesperidin reached 58.6 mg/g, which was comparable to the amount obtained after extraction using DMSO:methanol (1:1, v/v) as a solvent for 30 min at room temperature. Heating temperature and time for isolation of hesperidin crystallites were optimised as 140 °C and 8 min by using response surface methodology. Under this optimal condition, 86.8% (47.7 mg/g) of total hesperidin was isolable by MAE and low-temperature storage (5 °C, 24 h). 相似文献
55.
Shimizu T Iijima K Miyabayashi K Ogawa Y Miyazaki H Sasada H Sato E 《Reproduction (Cambridge, England)》2007,134(5):677-682
Vascular endothelial growth factor (VEGF) expression in granulosa cells is associated with the thecal vasculature growth during ovarian follicular development. We hypothesized that injection of VEGF gene fragments directly into the rat ovary would induce production of a large number of ovulatory follicles and that these follicles would ovulate. To test this hypothesis, we treated immature female rats with combinations of hormones and VEGF gene fragments. The animals were divided into two groups: one group received solution containing transfection reagents as a control (n = 5), while the other group received direct ovarian injection of VEGF gene fragments at 19 (n = 5), 21 (n = 5), 23 (n = 5), or 25 (n = 5) days after birth followed by i.p. administration of 20 IU equine chorionic gonadotropin (eCG) at the age of 26 days. Forty-eight hours after eCG injection, animals were given 20 IU human chorionic gonadotropin (hCG) i.p. and then the oocytes in both groups were counted. The maximum number of ovulated oocytes was obtained when the VEGF gene fragments were injected into the rat ovary at 21 days after birth. Histological examination revealed that the injection of VEGF gene fragments markedly increased the vascular density around the preovulatory follicles and also the number of these follicles. Our data provide the first reported evidence that most ovulatory follicles generated by injection of VEGF gene fragments are able to ovulate upon hCG treatment. These results demonstrate that injection of VEGF gene fragments directly into the ovary stimulates the development of antral follicles by inducing the formation of thecal vasculature in immature female rats. 相似文献
56.
Phase separation and dewetting processes of blend thin films of polystyrene (PS) and poly(vinyl methyl ether) (PVME) in two phase region have been studied in a wide film thickness range from 65 μm to 42 nm (∼2.5Rg, Rg being radius of gyration of a polymer) using optical microscope (OM), atomic force microscope (AFM) and small-angle light scattering (LS). It was found that both phase separation and dewetting processes depend on the film thickness and were classified into four thickness regions. In the first region above ∼15 μm the spinodal decomposition (SD) type phase separation occurs in a similar manner to bulk and no dewetting is observed. This region can be regarded as bulk. In the second region between ∼15 and ∼1 μm, the SD type phase separation proceeds in the early stage while the characteristic wavelength of the SD decreases with the film thickness. In the late stage dewetting is induced by the phase separation. In the third region between ∼1 μm and ∼200 nm the dewetting is observed even in the early stage. The dewetting morphology is very irregular and no definite characteristic wavelength is observed. It is expected that the irregular morphology is induced by mixing up the characteristic wavelengths of the phase separation and the dewetting. In the fourth region below ∼200 nm the dewetting occurs after a long incubation time with a characteristic wavelength, which decreases with the film thickness. It is considered that the layered structure is formed in the thin film during the incubation period and triggers the dewetting through the capillary fluctuation mechanism or the composition fluctuation one. 相似文献
57.
The kinetics of the swelling of sodium polyacrylate (NaPA), a hydrophilic polymer, was studied gravimetrically, by microscopic observation, and calorimetrically. The swelling process followed first-order kinetics and the rate constant was of the order of 10?2 s?1. The gravimetric method, however, was not useful for kinetic studies. The rate constant was depressed by the addition of sodium chloride. The activation energy of the swelling was 46.0 ± 6.2 (kJ mol?1) and decreased with the increase in sodium chloride concentration. In acid solution, the activation energy was almost the same as that in water. The heat of the swelling was 196 ± 17 J g?1 and did not vary with the addition of sodium chloride. © 1993 John Wiley & Sons, Inc. 相似文献
58.
In this paper, we present a self-consistent and 3D quantum simulator for Si-nanowire transistors based on the Wigner function model and multidimensional Schrodinger-Poisson algorithm. To achieve a sufficient numerical accuracy for calculating subthreshold current, we introduced a third-order differencing scheme for discretizing the drift term in the Wigner transport equation. By comparing with semiclassical Boltzmann and nonequilibrium Green's function approaches, the validity of the present simulator is confirmed. We also demonstrate that the source-drain tunneling is a critical physical phenomenon related to a scaling limit of nanowire devices, and the semiclassical simulation measurably underestimates a minimum gate length. 相似文献
59.
Kiyoharu Nakagawa Hirokazu Oda Akira Yamashita Masahiro Okamoto Yoichi Sato Hidenori Gamo Mikka Nishitani-Gamo Kazuyuki Ogawa Toshihiro Ando 《Journal of Materials Science》2009,44(1):221-226
We developed a novel spherical carbon material. The spherical carbon is composed of a high density of carbon nanotubes or
nanofilaments, and includes an oxidized diamond particle as a core. Syntheses of this carbon in high volume with high selectivity
may be possible. It is expected that this carbon will be useful as a catalyst material for fuel cells, electric double-layer
capacitors, etc. 相似文献
60.
T. Katsumi H. Kodama T. Matsuo H. Ogawa N. Tsuboi K. Hori 《Combustion, Explosion, and Shock Waves》2009,45(4):442-453
A new composition of hydroxylammonium nitrate based solution containing ammonium nitrate, methanol, and water was developed
for monopropellant in a reaction control system (RCS) as an alternative to conventional hydrazine. In comparison with hydrazine,
this solution has a 20% higher specific impulse, 1.4 times higher density, and lower freezing point and toxicity. The linear
burning rate of the solution is moderate at the operating pressures of RCS thrusters. It was found that the linear burning
rate had some characteristics whose mechanisms had not been understood. The combustion mechanism of this solution was investigated.
The burning behavior was observed using a medium speed camera, and a temperature profile for the combustion wave was measured
with a 2.5 μm diameter thermocouple. From these results, the instability of the liquid-gas interface may trigger a sudden
increase in the burning rate, and methanol was found to be effective in reducing the bubble growth rate in the solution. The
reactivity of several catalysts was evaluated in an open-cup test, and the S405 catalyst for hydrazine showed the best performance
among them. Thruster tests were conducted using the S405 catalyst with variation in the propellant mass flow rate, catalyst
bed configuration, and length-to-diameter ratio of the combustor. As a result, parameters were determined that ensured long
operating time. The model thruster operated stably for up to 100 sec with a specific impulse I
sp = 240 sec, which corresponds to a 90% efficiency.
__________
Translated from Fizika Goreniya i Vzryva, Vol. 45, No. 4, pp. 109–120, July–August, 2009.
An erratum to this article can be found at 相似文献