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181.
182.
Sekita K Umemura T Saito M Ogawa Y Ueno K Kaneko T Uchida O Matsushima Y Kawasaki Y Inoue T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(3):148-154
A subchronic toxicity study on kooroo color was conducted using F344 rats of both genders. Kooroo color is an extract of yam root, Dioscorea matudai Hayata, of which the major components are known to be flavonoid pigments. Use of kooroo as a food color is permitted by the Food Sanitation Law in Japan, but the chronic toxicity has not been evaluated in the literature. Rats were fed the product of kooroo color (PKC) at doses of 0.5%, 1.50%, and 5.0% in basal powder diet, while control groups received PKC-free basal diet, for ninety days. A vehicle control given propylene glycol (PG) alone, at the same dosage that the 5.0% group received, was included, because PKC used in this study contained ca. 80 percent PG, used as an extractant during the manufacturing processes. Daily observation of general behavior, and weekly measurement of body weight as well as food consumption were performed. Hematological, serum biochemical and anatomopathological examinations were conducted at the end of administration. No abnormalities ascribable to the treatment with PKC or PG were noted in any examination in this study. Hence, dietary intake of 5.0% of PKC, i.e., 2,993 mg/kg/day for males, and 3,376 mg/kg/day for females, as a mean daily intake for 90 days, had no observable adverse effect in F344 rats. Therefore, kooroo color has no significant general toxicity, and its toxicity, if any, is of a very low order. 相似文献
183.
Kenji Kawasaki Tomohiro Yoshida Hideo Yano Osamu Ishikawa Tohru Hata 《Journal of Low Temperature Physics》2002,126(1-2):229-234
We have studied superfluid
3
He in 0.8 m slab geometry by cw-NMR method. The static magnetic field for NMR was 22 mT and was perpendicularly applied to the surface. At pressures from 5 bar to 27 bar, we observed the negative shifts of NMR frequencies below the transition temperatures. Moreover we observed the fast order phase transition with the supercooling phenomena at lower temperatures, but NMR frequencies did not show a jump as they do at the A-B transition in the bulk liquid. Although the phase at low temperatures seemed to be B-phase, NMR frequencies still had the negative shifts. 相似文献
184.
A direct nanoflow liquid chromatography-tandem mass spectrometry system for interaction proteomics 总被引:11,自引:0,他引:11
Natsume T Yamauchi Y Nakayama H Shinkawa T Yanagida M Takahashi N Isobe T 《Analytical chemistry》2002,74(18):4725-4733
One of the strategies of functional proteomics, research aiming to discover gene function at the protein level, is the comprehensive analysis of protein-protein interactions related to the functional linkage among proteins and analysis of functional cellular machinery to better understand the basis of cell functions. Here, we describe the direct nanoflow LC (DNLC) system, which is equipped with a fritless high-resolution electrospray interface column packed with 1-microm reversed-phase (RP) beads and a novel splitless nanoflow gradient elution system to operate the column. Using RP-DNLC at an extremely slow flow rate, <50 nL/min, combined with data-dependent collision-induced dissociation tandem MS (MS/MS) and computer-assisted retrieval of spectra, we identified approximately 100 protein components in a biological complex such as a premature mammalian ribosome pull-down from cultured cells when we used an epitope-tagged protein as bait. Because this analysis is most sensitive, requires approximately 0.2 microg of total protein, and is a fully automated 1-h process, we anticipated that it should be an excellent tool for analyzing a limited amount of functional multi-protein complexes in cells. 相似文献
185.
The hybrid input-output algorithm (HIO) used for phase retrieval is in many cases combined with the error-reduction algorithm (ER) to attempt to stabilize the HIO. However, in our previous paper [J. Opt. Soc. Am. A 16, 2163 (1999)], it was demonstrated that this combination makes it more likely that the resultant algorithm will fall into a periodic state before reaching a solution because the values of the input object outside the support, which is imposed as the object-domain constraint, are set to be zero in the intervals in which the ER is implemented. This paper deals with this problem inherent in the combination algorithm. The converging part of the HIO (CPHIO), which is an algorithm we previously developed [J. Opt. Soc. Am. A 15, 2849 (1998)], can be thought of as an extension of the ER for the case in which the input object can have nonzero values outside the support. Keeping this in mind, the algorithm is then constructed by combining the HIO with the CPHIO instead of with the ER. The computer simulation results that demonstrate the effectiveness of the proposed algorithm are given. 相似文献
186.
Ogura S Kaneko K Miyajima S Ohshima K Yamaguchi K Mochizuki T 《Proteomics. Clinical applications》2008,2(12):1620-1627
Proteins secreted from specific cancer cells have a high potential for use as tumor markers. We identified secreted proteins produced by 15 different carcinoma cell lines grown in serum-free medium using MS/MS. Proneurotensin/neuromedin N (proNT/NMN) was found in conditioned medium from four of seven small cell lung carcinoma cell lines but not from eight nonsmall cell lung carcinoma cell lines. These results indicate proNT/NMN has potential as a specific tumor marker of small cell lung carcinoma. 相似文献
187.
An autonomous robot Khepera was simulated with a sensory-motor model, which evolves in the genetic algorithm (GA) framework, with the fitness evaluation in terms of the navigation performance in a maze course. The sensory-motor model is a developed neural network decoded from a graph-represented chromosome, which is evolved in the GA process with several genetic operators.It was found that the fitness landscape is very rugged when it is observed at the starting point of the course. A hypothesis for this ruggedness is proposed, and is supported by the measurement of fractal dimension. It is also observed that the performance is sometimes plagued by Loss of Robustness, after the robot makes major evolutionary jumps. Here, the robustness is quantitatively defined as a ratio of the averaged fitness of the evolved robot navigating in perturbed environments over the fitness of the evolved robot in the referenced environment.Possible explanation of robustness loss is the over-adaptation occurred in the environment where the evolution was taken place. Testing some other possibilities for this loss of robustness, many simulation experiments were conducted which smooth out the discrete factors in the model and environment. It was found that smoothing the discrete factors does not solve the loss of robustness. An effective method for maintaining the robustness is the use of averaged fitness over different navigation conditions.The evolved models in the simulated environment were tested by down-loading the models into the real Khepera robot. It is demonstrated that the tendency of fitness values observed in the simulation were adequately regenerated. 相似文献
188.
This paper proposes an approach using large-scale text features for fault-prone module detection inspired by spam filtering.
The number of every text feature in the source code of a module is counted and used as data for training detection models.
In this paper, we prepared a naive Bayes classifier and a logistic regression model as detection models. To show the effectiveness
of our approaches, we conducted experiments with five open source projects and compared them with a well-known metrics set,
thereby achieving higher detection results. The results imply that large-scale text features are useful in constructing practical
detection models, and measuring sophisticated metrics is not always necessary for detecting fault-prone modules. 相似文献
189.
Wataru Murase Yukino Kamakura Serina Kawakami Ayaka Yasuda Momoka Wagatsuma Atsuhito Kubota Hiroyuki Kojima Tohru Ohta Mami Takahashi Michihiro Mutoh Takuji Tanaka Hayato Maeda Kazuo Miyashita Masaru Terasaki 《International journal of molecular sciences》2021,22(24)
Fucoxanthin (Fx) is a marine carotenoid with anti-inflammatory and anti-cancer properties in various animal models of carcinogenesis. However, there is currently no information on the effects of Fx in animal models of pancreatic cancer. We investigated the chemopreventive effects of Fx in C57BL/6J mice that received allogenic and orthotopic transplantations of cancer cells (KMPC44) derived from a pancreatic cancer murine model (Ptf1aCre/+; LSL-krasG12D/+). Using microarray, immunofluorescence, western blot, and siRNA analyses, alterations in cancer-related genes and protein expression were evaluated in pancreatic tumors of Fx-administered mice. Fx administration prevented the adenocarcinoma (ADC) development of pancreatic and parietal peritoneum tissues in a pancreatic cancer murine model, but not the incidence of ADC. Gene and protein expressions showed that the suppression of chemokine (C-C motif) ligand 21 (CCL21)/chemokine receptor 7 (CCR7) axis, its downstream of Rho A, B- and T-lymphocyte attenuator (BTLA), N-cadherin, αSMA, pFAK(Tyr397), and pPaxillin(Tyr31) were significantly suppressed in the pancreatic tumors of mice treated with Fx. In addition, Ccr7 knockdown significantly attenuated the growth of KMPC44 cells. These results suggest that Fx is a promising candidate for pancreatic cancer chemoprevention that mediates the suppression of the CCL21/CCR7 axis, BTLA, tumor microenvironment, epithelial mesenchymal transition, and adhesion. 相似文献
190.
Steady-state and time-resolved fluorescence properties of poly(N-vinylcarbazole) (PVCz) dispersed in a polystyrene (PS) cast film were studied under tensile loadings at room temperature. The excited monomer emission of PVCz located around 350 nm decreased with increasing applied tensile strain from 0 to 0.8%. The strain enhanced the emission which was ascribed to the partial-overlap excimer of PVCz in a 360–430 nm region. The emission due to the full-overlap excimer of PVCz between 430 and 500 nm was unchanged by the action of the tensile loadings. The ratio of fluorescence intensities at 375 nm and 345 nm I375/I345 was proportional to the applied strain. The time-resolved fluorescence study indicated that the lifetimes of the excited monomer and of the partial-overlap excimer were not affected by the strain. The obtained results mean that the strain applied to the PS matrix increases the partial-overlap conformation of two adjacent carbazolyl chromophores in a PVCz chain and suggest that PVCz is a useful probe for detecting residual strains in polymer matrices. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 1569–1573, 1997 相似文献