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851.
852.
Lymphatic transport of a mixture of medium-chain TAG (MCT) and long-chain TAG (LCT) was studied in lymph-cannulated rats. Animals were administered a test emulsion containing either triolein, tricaprylin, or a 1∶1 mixture of triolein and tricaprylin, and the lymph was collected for 24 h. The lymphatic recovery rate of medium-chain FA (MCFA) was significantly higher in rats given the TAG mixture than in those given MCT alone. The lymphatic recovery rate of long-chain FA (LCFA) also was significantly higher in rats given the TAG mixture than in those given LCT alone. No TAG containing three MCFA (i.e., MCT) was detected, and 37.7% of TAG containing one or two MCFA was detected in the lymph TAG when rats were given the TAG mixture. These results indicate that lymphatic transport of MCFA and LCFA can be modified by the combination of MCT and LCT.  相似文献   
853.
854.
SiO2 thin films were deposited on the inner wall of a narrow commercial poly(propylene) tube with inner/outer diameters of 1.0 mm/3.0 mm by plasma-enhanced chemical vapor deposition using He or Ar carrier gases and tetraethoxysilane (TEOS)/O2 feedstock gases at high pressures from 30 kPa to atmospheric pressure and at room temperature. A glow μplasma was generated inside the tube by a radio frequency (RF 13.56 MHz) capacitively coupled discharge. X-ray photoelectron spectra and infrared spectra revealed that the inner surface of the plasma-treated tube was covered by a SiO2 film. Scanning electron microscopy images indicated that the film produced by He/TEOS/O2 μplasma had a smooth surface whereas the surface of the film produced by Ar/TEOS/O2 μplasma appeared granulated. Typical deposition rates of approximately 300 nm/min were obtained by He/TEOS/O2 μplasma at atmospheric pressure and a RF power of 11 W.  相似文献   
855.
Recently, torsional oscillator (Yamamoto et al. in Phys. Rev. Lett. 93:075302, 2004) and ultrasound (Kobayashi et al. in AIP Conf. Proc. 128:797, 2007) measurements were carried out for pressurized 4He filled in a nanoporous glass (Gelsil), and the superfluid transition temperature T C shows a different pressure dependence. Thus motivated, we have performed simultaneous measurements with a torsional oscillator and with ultrasound for pressurized 4He in Gelsil. T C is in agreement between the two techniques at all pressures, and the superfluid component above 0.5 K shows most of the same temperature dependence. Furthermore, it was found that the χ-factor (the fraction of superfluid which remains locked to the substrate ) is independent of measuring frequency between the torsional oscillator (kHz-order) and the ultrasound (MHz-order) ranges.  相似文献   
856.
The behaviour of uptake of the benzenecarboxylate ions, C6H6-n(COO)nn (n = 1–6), in aqueous solutions by rock-salt type magnesium aluminium oxide, Mg(1-x)(2+x)Al2x/(2+x)O (x = 0.17, 0.30, 0.33) was investigated at 0.70°C. All the benzenecarboxylate ions were taken up from solution competitively with OH- to form the hydrotalcite-like layered double hydroxides. The uptake rate could be adequately described by a surface chemical reaction controlled shrinking core model, and the apparent activation energy was c. 60 kJ mol?1. The selectivity of anion uptake increased with increasing the charge density of the benzenecarboxylate ions. The amount of benzenecarboxylate ions incorporated in the interlayer of hydrotalcite and the selectivity of uptake for benzenecarboxylate possessing higher electric change increased with increasing aluminium content in the magnesium aluminium oxide.  相似文献   
857.
Cyclic nucleoside monophosphates (cNMPs) play key roles in many cellular regulatory processes, such as growth, differentiation, motility, and gene expression. Caged derivatives that can be activated by irradiation could be powerful tools for studying such diverse functions of intracellular second messengers, since the spatiotemporal dynamics of these molecules can be controlled by irradiation with appropriately focused light. Here we report the synthesis, photochemistry, and biological testing of 6-bromo-7-hydroxycoumarin-4-ylmethyl esters of cNMP (Bhc-cNMP) and their acetyl derivatives (Bhc-cNMP/Ac) as new caged second messengers. Irradiation of Bhc-cNMPs quantitatively produced the parent cNMPs with one-photon uncaging efficiencies (Phiepsilon) of up to one order of magnitude better than those of 2-nitrophenethyl (NPE) cNMPs. In addition, two-photon induced photochemical release of cNMP from Bhc-cNMPs (7 and 8) can be observed with the two-photon uncaging action cross-sections (delta(u)) of up to 2.28 GM (1 GM=10(-50) cm(4) s photon(-1)), which is the largest value among those of the reported Bhc-caged compounds. The wavelength dependence of the delta(u) values of 7 revealed that the peak wavelength was twice that of the one-photon absorption maximum. Bhc-cNMPs showed practically useful water solubility (nearly 500 microM), whereas 7-acetylated derivatives (Bhc-cNMPs/Ac) were expected to have a certain membrane permeability. Their advantages were demonstrated in two types of biological systems: the opening of cAMP-mediated transduction channels in newt olfactory receptor cells and cAMP-mediated motility responses in epidermal melanophores in scales from medaka fish. Both examples showed that Bhc and Bhc/Ac caged compounds have great potential for use in many cell biological applications.  相似文献   
858.
Dendritic cells (DCs) are potent antigen-presenting cells that play important roles in regulating immune responses in cancer. Immunotherapy using these immunocytes has become an accepted therapeutic modality. We previously reported that hyperthermia using magnetic nanoparticles induces antitumor immunity, which could be activated by adjuvant including cytokines. In the present study, we investigated the therapeutic effects of hyperthermia combined with DC immunotherapy on mouse EL4 T-lymphoma. Magnetite cationic liposomes (MCLs) have a positive surface charge and generate heat in an alternating magnetic field (AMF) due to hysteresis loss. MCLs were injected into an EL4 nodule in C57BL/6 mice, which were subjected to AMF for 30 min. The temperature at the surface of the tumor reached 45 degrees C and was maintained by controlling the magnetic field intensity. Hyperthermia treatment was repeated twice with 24 h intervals. After hyperthermia, immature DCs were directly injected into the EL4 nodule. As a result, complete regression of tumors in 75% (6/8) of the mice was observed, while the percentage of complete regression of tumors was 12.5% (1/8) in the case of mice treated by hyperthermia alone. This novel cancer therapy, which we have termed "heat immunotherapy", may be applicable to patients with advanced malignancies.  相似文献   
859.
Ultraviolet irradiation of mulberry leaves caused a reduced feeding response inBombyx mori larvae (ca. 22% reduction in consumption as compared with control). Sucrose content of the foliage decreased after exposure to UV irradiation (0.5 mW/cm2 for 1 hr. Electrophysiological responses of the sensilla styloconica-I to sucrose concentration (ca. 0–80 mg/g) showed a reduced response to UV-irradiated foliage when compared with the control. From feeding, gustatory, and electrophysiological responses, as well as the measurement of sucrose contents of the leaves, we concluded that the reduced feeding response to UV-irradiated leaves is due to the reduced sucrose content of the mulberry leaves, thus reducing pleogostimulatory levels.  相似文献   
860.
The objective of this paper is to present the performance comparison of the impulse turbines for different diameters. In the study, the investigation has been performed experimentally by model testing for some diameters, especially 0.3 m and 0.6 m. The experiment was performed for Reynolds number range of 0.17 X 105—1.09X 105 and for different values of hub-to-tip ratiov ranging from 0.6 to 0.85. As a result, it was found that the critical Reynolds number is to be around 0.5 X 105 for v=0.6 and 0.4X 105 for v=0.7. For the hub-to-tip ratio, the optimum value is 0.7 when the turbine is operated at lower Reynolds number. However, its value seems to be 0.6 at higher Reynolds number in the tested range.  相似文献   
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