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排序方式: 共有542条查询结果,搜索用时 15 毫秒
531.
532.
533.
Yamaguchi A Shimizu K Mishima T Hattori H Katsuda S Sato H Ueda N Sato N 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2006,47(6):263-267
A simple and rapid detection of short tandem repeat (STR) markers was studied as a screening test for individual identification of cattle. DNAs were extracted from eight commercial beef samples by a proteinase K-boil method followed by purification with 2-propanol precipitation. Five STR markers, known to be highly polymorphic, were amplified by PCR and analyzed both by a conventional sequencing analysis (SEQ) and by a proposed microchip electrophoresis (MEP). Every marker revealed high polymorphism, such as 5-9 alleles in SEQ analysis, and 4-6 alleles in MEP analysis. This simple and rapid MEP analysis is expected to be an effective screening tool with use of confirmatory SEQ analysis. 相似文献
534.
This paper reviews recent progress in broad-band Raman amplifiers for wavelength-division-multiplexed (WDM) applications. After the fundamentals of Raman amplifiers are discussed in contrast to erbium-doped fiber amplifiers, a new technique called “WDM pumping” is introduced to obtain ultrabroad and flat gain in Raman amplifiers only using WDM diode pumps. The design issues of this technique are then developed to realize outstanding performances such as 100 nm of flat gain bandwidth, 0.1 dB flatness over 80 nm, and so forth 相似文献
535.
Noriyuki Oba Hisao Sugimura Yasuhiko Umehara Masayuki Yoshida Talzo Kimura Takaji Yamaguchi 《Lipids》1992,27(9):701-705
A water-in-oil-in-water (W/O/W) emulsion composed of oleic acid was used as a carrier of carboxyfluorescein (CF)via the enteral route, as a model for future drug transport. The absorption of CF in the small intestine of rats given the emulsion
(W/O/W group) was compared with the absorption in a group administered CF alone (CF group), and a surface-active agent in
CF solution (MM group). Higher amounts of CF were absorbed in the W/O/W and MM groups than in the CF group. At 120 min, the
amount of CF remaining in the intestinal tract was smaller in the MM group than in the W/O/W group. In the early period, CF
excretion into bile was higher in the MM group than in the W/O/W group was higher than in the MM group (non-specific). The
blood CF level was significantly higher at 240 and 360 min in the W/O/W group than in the other two groups. The highest concentration
in lymph was found in the W/O/W group. The W/O/W emulsion was considered superior to the micelles because it maintained a
higher blood level of CF over long periods and transferred it to the lymph. This suggests that the W/O/W emulsion is applicable
as a drug carriervia the enteral route. 相似文献
536.
Adsorbents are important components in adsorption refrigeration. The diameter of an adsorbent can af-fect the heat and mass transfer of an adsorber. The effect of particle diameter on effective thermal conductivity was investigated. The heat transfer coefficient of the refrigerant and the void rate of the adsorbent layer can also affect the effective thermal conductivity of adsorbents. The performance of mass transfer in the adsorber is better when pressure drop decreases. Pressure drop decreases with increasing permeability. The permeability of the adsorbent layer can be improved with increasing adsorbent diameter. The effect of adsorbent diameter on refrigeration output power was experimentally studied. Output power initially increases and then decreases with increasing diameter under different cycle time conditions. Output power increases with decreasing cycle time under similar diameters. 相似文献
537.
Nd3+ -ion-doped ZnCl2 -based glasses were prepared via the melt-quenching method. The Nd3+ -ion upconversion excitation mechanism and the ability to disperse Nd3+ ions into ZnCl2 -based glasses were investigated using absorption and upconversion fluorescence spectra of Nd3+ ions. The ZnCl2 -based glass that had an average cationic radius equal to the ionic radius of Nd3+ (98 pm) had the greatest ability to disperse Nd3+ ions. The 20KCl·25BaCl2 ·55ZnCl2 glass, which had the average cationic radius nearest to 98 pm, dispersed Nd3+ ions the most, and it had the strongest upconversion fluorescence. 相似文献
538.
539.
Tetsuya Yamamoto Nobuaki Miyaji Kiminari Kataoka Kyohei Nishida Kanto Nagai Noriyuki Kanzaki Yuichi Hoshino Ryosuke Kuroda Takehiko Matsushita 《International journal of molecular sciences》2021,22(19)
Overexpression of silent information regulator 2 ortholog 1 (SIRT1) is associated with beneficial roles in aging-related diseases; however, the effects of SIRT1 overexpression on osteoarthritis (OA) progression have not yet been studied. The aim of this study was to investigate OA progression in SIRT1-KI mice using a mouse OA model. OA was induced via destabilization of the medial meniscus using 12-week-old SIRT1-KI and wild type (control) mice. OA progression was evaluated histologically based on the Osteoarthritis Research Society International (OARSI) score at 4, 8, 12, and 16 weeks after surgery. The production of SIRT1, type II collagen, MMP-13, ADAMTS-5, cleaved caspase 3, Poly (ADP-ribose) polymerase (PARP) p85, acetylated NF-κB p65, interleukin 1 beta (IL-1β), and IL-6 was examined via immunostaining. The OARSI scores were significantly lower in SIRT1-KI mice than those in control mice at 8, 12, and 16 weeks after surgery. The proportion of SIRT1 and type II collagen-positive-chondrocytes was significantly higher in SIRT1-KI mice than that in control mice. Moreover, the proportion of MMP-13-, ADAMTS-5-, cleaved caspase 3-, PARP p85-, acetylated NF-κB p65-, IL-1β-, and IL-6-positive chondrocytes was significantly lower in SIRT1-KI mice than that in control mice. The mechanically induced OA progression was delayed in SIRT1-KI mice compared to that in control mice. Therefore, overexpression of SIRT1 may represent a mechanism for delaying OA progression. 相似文献
540.
Yotesawee Srisomboon Noriyuki Ohkura Koji Iijima Takao Kobayashi Peter J. Maniak Hirohito Kita Scott M. OGrady 《International journal of molecular sciences》2021,22(16)
Polyethyleneimine (PEI) induced immune responses were investigated in human bronchial epithelial (hBE) cells and mice. PEI rapidly induced ATP release from hBE cells and pretreatment with glutathione (GSH) blocked the response. PEI activated two conductive pathways, VDAC-1 and pannexin 1, which completely accounted for ATP efflux across the plasma membrane. Moreover, PEI increased intracellular Ca2+ concentration ([Ca2+]i), which was reduced by the pannexin 1 inhibitor, 10Panx (50 μM), the VDAC-1 inhibitor, DIDS (100 μM), and was nearly abolished by pretreatment with GSH (5 mM). The increase in [Ca2+]i involved Ca2+ uptake through two pathways, one blocked by oxidized ATP (oATP, 300 μM) and another that was blocked by the TRPV-1 antagonist A784168 (100 nM). PEI stimulation also increased IL-33 mRNA expression and protein secretion. In vivo experiments showed that acute (4.5 h) PEI exposure stimulated secretion of Th2 cytokines (IL-5 and IL-13) into bronchoalveolar lavage (BAL) fluid. Conjugation of PEI with ovalbumin also induced eosinophil recruitment and secretion of IL-5 and IL-13 into BAL fluid, which was inhibited in IL-33 receptor (ST2) deficient mice. In conclusion, PEI-induced oxidative stress stimulated type 2 immune responses by activating ATP-dependent Ca2+ uptake leading to IL-33 secretion, similar to allergens derived from Alternaria. 相似文献