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排序方式: 共有390条查询结果,搜索用时 281 毫秒
381.
Masaki Michishita Shiori Ezaki Kikumi Ogihara Yuko Naya Daigo Azakami Takayuki Nakagawa Nobuo Sasaki Toshiro Arai Takuo Shida Kimimasa Takahashi 《Research in veterinary science》2014
Tumor-initiating cells (TICs) or cancer stem cells (CSCs), a small subset of tumor cells, are involved in tumor initiation, progression, recurrence and metastasis. In human hepatocellular carcinoma (HCC), TICs are enriched with cell surface markers and have the ability to self-renew and differentiate tumors at a high frequency. We established a canine HCC cell line, HCC930599, and analyzed it for stem and progenitor cell marker expression using flow cytometry. HCC930599 showed high CD44 and CD29, moderate CD90, and low CD133, CD34, CD24, CD117, and CD13 expression. CD90+CD44+ and CD90−CD44+ cells were characterized using the in vitro sphere assay and an in vivo transplant model. CD90+CD44+ cells acquired enhanced self-renewal capacity, proliferative activity and tumourigenicity compared with CD90−CD44+ cells, suggesting that TICs exist in the HCC930599 cell line and that CD90 is a marker for enriched TICs. Understanding TIC characteristics may help elucidate hepatic carcinogenesis and HCC therapy development. 相似文献
382.
383.
Caffeoylsophorose in a red vinegar produced through fermentation with purple sweetpotato 总被引:3,自引:0,他引:3
Terahara N Matsui T Fukui K Matsugano K Sugita K Matsumoto K 《Journal of agricultural and food chemistry》2003,51(9):2539-2543
Recently, a new red vinegar has been developed via fermentation with the storage root of purple-fleshed sweetpotato, Ipomoea batatas L. cv. Ayamurasaki. The red vinegar had a higher antioxidative activity than white or black vinegars. The red vinegar contained some new components possibly derived from the original purple sweetpotato. A major component was isolated using preparative HPLC, and the chemical structure was determined to be 6-O-(E)-caffeoyl-(2-O-beta-d-glucopyranosyl)-alpha-d-glucopyranose (caffeoylsophorose) by MS and NMR. Because the caffeoylsophorose showed a high antioxidative activity, it plays an important functional role in red vinegar as do anthocyanins and other components. Examination of the mechanism of formation is now in progress. 相似文献
384.
3维图像处理系统在稻米品质检测中的应用研究 总被引:12,自引:7,他引:12
侯彩云 Seiichi Oshit Yasuhisa Seo Yoshinori Kawagoe Toru Torii Kenichi Kudoh Toshiro Higuchi Gabsoo Do 《农业工程学报》2001,17(3):92-95
利用微切片3维图像处理系统对稻米的品质特性进行了探索性的研究。结果表明,借助于3维可视化技术,可以对稻谷的外观品质、营养品质及蒸煮品质等进行更为直观且客观的观察与测定。尤其是在营养成分分布密度的评价、心白米内部组织的分析、蒸煮过程中组织结构变化的观测等方面,取得了传统研究方法难以获得的结果。利用该系统对垩白度的定量化测定,为食品的定量形态学研究开辟了一条新的研究途径。 相似文献
385.
The addition of a bulking agent achieves the bulking of paper and increases the pore volume. In this study, the effect of adding bulking agents with various alkyl chain lengths (C14, C18, and C22) on the bulk of paper, the sizing performance, and sheet wettability was evaluated. The bulking effect of a bulking agent with a short alkyl chain length (C14) was large, and reduction in the sheet tensile strength was confirmed to be suppressed. Good sheet sizing performance was achieved when a bulking agent was used with an alkyl ketene dimer (AKD). When 0.1% or more of AKD was added, using a bulking agent with a shorter alkyl chain length increased the improvement in the sizing degree. Pyrolysis gas chromatography measurements of the amount of reacted AKD revealed that the addition of a bulking agent increased the AKD content of the sheet. The sheet contact angle measured by the two-liquid method tended to increase with increasing alkyl chain length. However, the sheet contact angle was not directly correlated with the Stöckigt sizing degree. By using 1% ferric chloride (FeCl3) and 2% ammonium thiocyanate (NH4SCN) aqueous solution, which are used for measuring the Stöckigt sizing degree, the time-dependent change in the contact angle on the paper sheet surface was measured to evaluate wettability. The Stöckigt sizing degree of paper sheets was found to be greatly influenced by the sheet wettability by NH4SCN solution. In the case of 2% NH4SCN aqueous solution, different samples exhibited large wettability differences. When 0.2% or less of AKD was added, the effect of the concentration on the contact angle was confirmed to be large at all NH4SCN concentrations. 相似文献
386.
This study evaluated the potential of steam pre-treatment for making highly compressed phenol-formaldehyde (PF) resin-impregnated
wood at a low pressing pressure. Sawn veneers of Japanese cedar (Cryptomeria japonica) were first subjected to saturated steam at different steaming temperatures (140°-200°C), followed by impregnation with a
20% low molecular weight PF resin aqueous solution resulting in a weight gain of around 50%-55%. Four oven-dried treated veneers
were laminated and compressed up to a pressing pressure of 1 MPa at a pressing temperature of 150°C and pressing speed of
5 mm/min, and the pressure was held for 30 min. Steam treatment, causing partial hydrolysis of hemicellulose, accelerated
the compressibility of Japanese cedar in the PF resin-swollen condition. As a consequence, a discernible increment in density
was achieved at a pressing pressure of 1 MPa due to steam pretreatment between 140° and 200°C for 10 min. It was also found
that even a short steaming time such as 2 min at 160°C is sufficient for obtaining appreciable compression of PF resin-impregnated
wood. The density, Young’s modulus, and bending strength of steam-treated (200°C for 10 min) PF resin-impregnated wood composite
reached 1.09 g/cm3, 20 GPa, and 207MPa, respectively. In contrast, the values of untreated PF resin-impregnated wood composite were 0.87 g/cm3, 13 GPa, and 170MPa, respectively. 相似文献
387.
Ryota Konda Seiichi Ohta Shigehiro Ishizuka Seiko Arai Saifuddin Ansori Nagaharu Tanaka Arisman Hardjono 《Soil biology & biochemistry》2008,40(12):3021-3030
We investigated spatial structures of N2O, CO2, and CH4 fluxes during a relatively dry season in an Acacia mangium plantation stand in Sumatra, Indonesia. The fluxes and soil properties were measured at 1-m intervals in a 1 × 30-m plot (62 grid points) and at 10-m intervals in a 40 × 100-m plot (55 grid points) at different topographical positions of the upper plateau, slope, and valley bottom in the plantation. Spatial structures of each gas flux and soil property were identified using geostatistical analysis. The means (±SD) of N2O, CO2, and CH4 fluxes in the 10-m grids were 0.54 (±0.33) mg N m−2 d−1, 2.81 (±0.71) g C m−2 d−1, and −0.84 (±0.33) mg C m−2 d−1, respectively. This suggests that A. mangium soils function as a larger source of N2O than natural forest soils in the adjacent province on Sumatra during the relatively dry season, while CO2 and CH4 emissions from the A. mangium soils were less than or consistent with those in the natural forest soils. Multiple spatial dependence of N2O fluxes within 3.2 m (1-m grids) and 35.0 m (10-m grids), and CO2 fluxes within 1.8 m (1-m grids) and over 65 m (10-m grids) was detected. From the relationship among N2O and CO2 gas fluxes, soil properties, and topographic elements, we suggest that the multiple spatial structures of N2O and CO2 fluxes are mainly associated with soil resources such as readily mineralizable carbon and nitrogen in a relatively dry season. The soil resource distributions were probably controlled by the meso- and microtopography. Meanwhile, CH4 fluxes were spatially independent in the A. mangium soils, and the water-filled pore space appeared to mainly control the spatial distribution of these fluxes. 相似文献
388.
Evaluation of the genetic structure of sika deer (Cervus nippon) in Japan's Kanto and Tanzawa mountain areas,based on microsatellite markers
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Sayaka Konishi Shoko Hata Sayumi Matsuda Kazushi Arai Yasushi Mizoguchi 《Animal Science Journal》2017,88(11):1673-1677
The browsing habits of sika deer (Cervus nippon) in Japan have caused serious ecological problems. Appropriate management of sika deer populations requires understanding the different genetic structures of local populations. In the present study, we used 10 microsatellite polymorphisms to explore the genetic structures of sika deer populations (162 individuals) living in the Kanto region. The expected heterozygosity of the Tanzawa mountain range population (Group I) was lower than that of the populations in the Kanto mountain areas (Group II). Our results suggest that moderate gene flow has occurred between the sika deer populations in the Kanto mountain areas (Group II), but not to or from the Tanzawa mountain range population (Group I). Also, genetic structure analysis showed that the Tanzawa population was separated from the other populations. This is probably attributable to a genetic bottleneck that developed in the Tanzawa sika deer population in the 1950s. However, we found that the Tanzawa population has since recovered from the bottleneck situation and now exhibits good genetic diversity. Our results show that it is essential to periodically evaluate the genetic structures of deer populations to develop conservation strategies appropriate to the specific structures of individual populations at any given time. 相似文献
389.
390.
Yuichi Takai Stephanie Powlin Yasuyuki Awasaki Toshiaki Yamauchi Tomoya Sano Haruyuki Takahashi Abdul-Hackam Ranneh Yuta Arai 《Journal of toxicologic pathology》2022,35(4):355
To develop safe subcutaneous formulations and minimize the risk of local irritation, it is essential to optimize the composition of active pharmaceutical ingredients and excipients. Depending on the physicochemical properties of the active pharmaceutical ingredient, additional excipients may be required to improve the stability and solubility of the active pharmaceutical ingredient. However, some of these excipients may not have been previously used in injectable drugs. Owing to the lack of safety data for such excipients, especially those used in subcutaneous dosing, it is important to evaluate their potential for local irritation during the early stages of formulation development. We evaluated the tolerability of 44 formulations with 24 candidate novel excipients, such as surfactants, polymers, and lipids, in a single subcutaneous dose in rats. Excipient formulations were administered as single bolus subcutaneous injections with an injection volume of 1 mL. The injection sites were observed for 2 days, and macroscopic and microscopic examinations were conducted. Local tolerability was evaluated on the basis of severity, incidence, and pathophysiology of each finding. Formulations that caused tissue degeneration or necrosis, which is indicative of tissue injury, were determined to be irritative and poorly tolerated. A single-dose subcutaneous screening study in rats was considered effective in ranking the safety of candidate excipients during the formulation optimization phase. 相似文献