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排序方式: 共有198条查询结果,搜索用时 46 毫秒
21.
Hydrogels that contain phosphate groups in side chains were studied for their usefulness in drug‐delivery soft contact lenses (SCLs). Naphazoline, a model drug having a cationic group, was incorporated into an SCL because of its phosphate groups and was released over a period of about 14 h. For the SCL, the naphazoline content was equivalent to the phosphate group content. It is suggested that drug‐delivery SCLs can be designed to contain the needed amount of a drug through the choice of the ionic group for the ligand. Furthermore, the SCL having amide groups and phosphate groups had high transparency and an unchanged shape. It is suggested that amide groups and phosphate groups must be introduced into the polymer in equimolar amounts to give the necessary polymer–drug interaction. Therefore, hydrogels having a drug‐delivery system were synthesized by the inclusion of a phosphate group and an amide group. These hydrogels are also applicable to SCL materials. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 731–735, 2005 相似文献
22.
A New and Efficient Fail-stop Signature Scheme 总被引:4,自引:0,他引:4
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Tung-Kuang Wu Chang Wu Yu Rei Heng Cheng Chia Hu Wu 《Wireless Personal Communications》2008,44(2):119-138
Medium access control (MAC) protocol is among the most active topics of research in ad hoc networks. With the CDMA-based MAC
protocol the code allocation plays an important role and has significant impact on the protocol performance. In this paper,
we propose a distributed CDMA code assignment protocol for the mobile ad hoc networks (MANETs). The protocol is mainly composed
of (1) a modified busy tone signaling mechanism that protects on-going data transmission as well as distributes code usage
information, and (2) a set of specially designed code selection rules that work by taking into consideration whether relevant
nodes are in the transmitting or receiving state. By combining the two proposed schemes with the conventional request-to-send
(RTS)/clear-to-send (CTS) dialogue and power control mechanism, our protocol is able to increase CDMA code reusability. The
simulation results indicate that the proposed protocol indeed performs better than the static and dynamic code assignment
methods (either with or without power control) in terms of successful transmission rate and successful code assignment rate.
And instead of sending continuously, the proposed modified busy tone mechanism only issues busy tone signal in randomly selected
cycles, which may save battery energy as compared to conventional busy tone implementations. Moreover, the proposed code selection
rules and the modified busy tone signaling may also be integrated into existing MAC protocols, either separately or in combination. 相似文献
26.
Akira Kaieda Dr. Masashi Takahashi Hiromi Fukuda Dr. Rei Okamoto Dr. Shinji Morimoto Masayuki Gotoh Takahiro Miyazaki Yuri Hori Satoko Unno Dr. Tomohiro Kawamoto Dr. Toshimasa Tanaka Dr. Sachiko Itono Terufumi Takagi Dr. Hiroshi Sugimoto Dr. Kengo Okada Dr. Weston Lane Dr. Bi-Ching Sang Dr. Kumar Saikatendu Dr. Shinichiro Matsunaga Dr. Seiji Miwatashi 《ChemMedChem》2019,14(24):2093-2101
We identified novel potent inhibitors of p38 mitogen-activated protein (MAP) kinase using a structure-based design strategy, beginning with lead compound, 3-(butan-2-yl)-6-(2,4-difluoroanilino)-1,3-dihydro-2H-imidazo[4,5-b]pyridin-2-one ( 1 ). To enhance the inhibitory activity of 1 against production of tumor necrosis factor-α (TNF-α) in human whole blood (hWB) cell assays, we designed and synthesized hybrid compounds in which the imidazo[4,5-b]pyridin-2-one core was successfully linked with the p-methylbenzamide fragment. Among the compounds evaluated, 3-(3-tert-butyl-2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyridin-6-yl)-4-methyl-N-(1-methyl-1H-pyrazol-3-yl)benzamide ( 25 ) exhibited potent p38 inhibition, superior suppression of TNF-α production in hWB cells, and also significant in vivo efficacy in a rat model of collagen-induced arthritis (CIA). In this paper, we report the discovery of potent, selective, and orally bioavailable imidazo[4,5-b]pyridin-2-one-based p38 MAP kinase inhibitors. 相似文献
27.
Asami Nishikori Yoshito Nishimura Rei Shibata Koh-ichi Ohshima Yuka Gion Tomoka Ikeda Midori Filiz Nishimura Tadashi Yoshino Yasuharu Sato 《International journal of molecular sciences》2021,22(8)
Immunoglobulin G4-related disease (IgG4-RD) is a systemic disorder characterized by tissue fibrosis and intense lymphoplasmacytic infiltration, causing progressive organ dysfunction. Activation-induced cytidine deaminase (AID), a deaminase normally expressed in activated B-cells in germinal centers, edits ribonucleotides to induce somatic hypermutation and class switching of immunoglobulin. While AID expression is strictly controlled under physiological conditions, chronic inflammation has been noted to induce its upregulation to propel oncogenesis. We examined AID expression in IgG4-related ophthalmic disease (IgG4-ROD; n = 16), marginal zone lymphoma with IgG4-positive cells (IgG4+ MZL; n = 11), and marginal zone lymphoma without IgG4-positive cells (IgG4- MZL; n = 12) of ocular adnexa using immunohistochemical staining. Immunohistochemistry revealed significantly higher AID-intensity index in IgG4-ROD and IgG4+ MZL than IgG4- MZL (p < 0.001 and = 0.001, respectively). The present results suggest that IgG4-RD has several specific causes of AID up-regulation in addition to inflammation, and AID may be a driver of oncogenesis in IgG4-ROD to IgG4+ MZL. 相似文献
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Rei Sonobe Yuta Miura Tomohito Sano Hideki Horie 《International journal of remote sensing》2018,39(5):1306-1320
Quantifying carotenoid contents has many applications in agriculture, ecology, and health science. Hyperspectral reflectance has been one of the promising tools for this purpose. However, previous studies were based on measurements under relatively low light–stress conditions. Therefore, assessing its robustness by using measurements under various levels of stress is required. In this study, the measurements of reflectance and carotenoid contents were carried out with four shading treatments including open–0%, 35%, 75%, and 90% shading to generate various chlorophyll/carotenoid ratios. Then the performances of 15 published hyperspectral indices and PROSPECT–D inversion were evaluated based on our data set for estimating leaf carotenoid contents. According to the ratio of performance to deviation, RNIR/R510, R720/R521–1, and PROSPECT–D inversion were applicable for this purpose, although calibration of the absorption coefficients was required for PROSPECT–D. Using them, root mean square percentage errors of 4.53–5.46% were achieved. Given that total chlorophyll/carotenoid ratios could be a good indicator for evaluating environmental stress in plants, PROSPECT–D, which also estimates total chlorophyll and anthocyanin contents, could be a strong tool for controlling the qualities of shade-grown tea. 相似文献
30.
This paper presents current research results for polygonal connections with hypocycloidal profiles (H‐profiles). It proposes a design concept including permissible stress with respect to limits of plasticity. Moreover, notch effect figures are specified for use in the nominal stress concept. A comparison with conventional shaft‐hub connections reveals the benefits of new polygonal connections. 相似文献