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1.
The family of T-cell immunoglobulin domain and mucin domain (TIM) proteins is identified to be expressed on T cells. A member of Tim family, Tim-3 (T cell immunoglobulin mucin 3) is selectively expressed on the surface of differentiated Th1 cells. Tim-3 might have an important role in the induction of autoimmune diseases by regulating macrophage activation and interacts with Tim-3 ligand to regulate Th1 responses. To determine the variation sites in the coding and promoter region of human Tim-3 gene, we performed variation scanning by direct sequencing using the genomic DNA isolated from the patients with asthma or allergic rhinitis and healthy controls without asthma and allergic rhinitis. We identified four single nucleotide polymorphisms (SNPs) including one novel SNPs (-1541C>T) and two variation sites (-1292_-1289delTAAA and -1282_-1278dupTAAAA) in the coding and promoter region of human Tim-3 gene in both the patients and healthy groups.  相似文献   
2.
Sterically hindered chiral Schiff base ligands 4a-d were prepared from an aldehyde derived from BINOL. The vanadium complexes of the ligands catalyze an efficient, enantioselective H2O2-promoted sulfoxidation of alkyl aryl sulfides, and enantioselectivities as high as 98-99% ee are observed in the sulfoxidation of benzyl aryl sulfides.  相似文献   
3.
P2X3 receptors (P2X3R) are ATP-gated ion channels predominantly expressed in C- and Aδ-fiber primary afferent neurons and have been introduced as a novel therapeutic target for neurological disorders, including neuropathic pain and chronic cough. Because of its localized distribution, antagonism of P2X3R has been thoroughly considered, and the avoidance of issues related to CNS side effects has been proven in clinical trials. In this article, benzimidazole-4,7-dione-based derivatives were introduced as a new chemical entity for the development of P2X3R antagonists. Starting from the discovery of a hit compound from the screening of 8364 random library compounds in the Korea Chemical Bank, which had an IC50 value of 1030 nM, studies of structure–activity and structure–property relationships enabled further optimization toward improving the antagonistic activities as well as the drug’s physicochemical properties, including metabolic stability. As for the results, the final optimized compound 14h was developed with an IC50 value of 375 nM at P2X3R with more than 23-fold selectivity versus P2X2/3R, along with properties of metabolic stability and improved solubility. In neuropathic pain animal models evoked by either nerve ligation or chemotherapeutics in male Sprague-Dawley rats, compound 14h showed anti-nociceptive effects through an increase in the mechanical withdrawal threshold as measured by von Frey filament following intravenous administration.  相似文献   
4.
High fatigue-resistant photochromic dithienylethenes were synthesized by controlling the oxidation state of 1,2-bis(2-methyl-1-benzothiophene-3-yl)perfluorocyclopentene (BTF6) and 1,2-bis(2,5-dimethylthien-3-yl)perfluorocyclopentene (DMTF6).  相似文献   
5.
柔性有源OLED显示器制造几点技术方面的考虑   总被引:2,自引:0,他引:2  
Juhn  S.  Yoo  Nackbong  Choi  Yong-Chul  Kim  In-Hwan  Kim  Seung-Chan  Byun  Sang-Hoon  Jung  Jong-Moo  Kim  Soo-Young  Yoon  Chang-Dong  Kim  In-Byeong  Kang  In-Jae  Chung  代永平 《现代显示》2009,20(2):21-24
AMOLED在柔性显示领域前途似锦。LG显示展示了一款全彩4in柔性AMOLED样机,衬底为80μm厚的不锈钢薄片,曲率达到5cm弯曲半径。本文就此项柔性显示技术所面临的挑战进行了探讨.包括柔性衬底衬底的传送、如何获得特性稳定可靠的TFT以使OLED的亮度和一致性适用于此项技术的商业化推广。  相似文献   
6.
7.
Efficient and reversible fluorescence modulation with excellent photo-stability was achieved from a sulfone form of diacetyl diarylethene, 1,2-bis(6-acetyl-2-methyl-1-benzothiophene-1,1-dioxide-3-yl)perfluorocyclopentene (DABTFO4). The DABTFO4 emits strong fluorescence in the closed-ring isomer even in the absence of extra fluorophores. The fluorescence quantum yield, fatigue resistance, and photo-cyclization yield of DABTFO4 were significantly improved compared with the unsubstituted 1,2-bis(2-methyl-1-benzothiophene-1,1-dioxide-3-yl)perfluorocyclopentene (BTFO4) and the sulfide analogue, 1,2-bis(6-acetyl-2-methyl-1-benzothiophene-3-yl)perfluorocyclopentene (DABTF6).  相似文献   
8.
Metal organic chemical vapor deposition has been investigated for growth of Bi2Te3 films on (0 0 1) GaAs substrates using trimethylbismuth and diisopropyltelluride as metal organic sources. The results of surface morphology, electrical and thermoelectric properties as a function of growth parameters are given. The surface morphologies of Bi2Te3 films were strongly dependent on the deposition temperatures. Surface morphologies varied from step-flow growth mode to island coalescence structures depending on deposition temperature. In-plane carrier concentration and electrical Hall mobility were highly dependent on precursor's ratio of VI/V and deposition temperature. By optimizing growth parameters, we could clearly observe an electrically intrinsic region of the carrier concentration at the temperature higher than 240 K. The high Seebeck coefficient (of −160 μVK−1) and good surface morphology of this material is promising for Bi2Te3-based thermoelectric thin film and two-dimensional supperlattice device applications.  相似文献   
9.
The reading of names and addresses is one of the most complex tasks in automated forms processing. This paper describes an integrated real-time system to read names and addresses on tax forms of the U.S. Internal Revenue Service. The Name and Address Block Reader (NABR) system accepts both machine-printed and hand-printed address block images as input. The application software has two major steps: document analysis (connected component analysis, address block extraction, label detection, hand-print/machine-print discrimination) and document recognition. Document recognition has two nonidentical streams for machine-print and hand-print: the key steps are address parsing, character recognition, word recognition, and postal database lookup. (ZIP+4 and City-State-ZIP files.) System output is a packet containing the results of recognition together with database access status file. Real-time throughput (8500 forms/h) is achieved by employing a loosely coupled multiprocessing architecture where successive input images are distributed to available address recognition processors. The functional architecture, software design, system architecture, and the hardware implementation are described. Performance evaluation on machine-printed and handwritten addresses are presented  相似文献   
10.
The synthesis of 3-acyltetramic acids, the substructure of bioactive natural products, via O-acylation of tetramic acids with carboxylic acids followed by acyl migration, has been investigated. This acylation sequence is mediated by N,N'-dicyclohexylcarbodiimide (DCC) and 4-dimethylaminopyridine (DMAP) and is very sensitive to the nature of the nitrogen substituent (R(1)), the nature of the carboxylic acid (R(2)CO(2)H), and the amount of DMAP. Acylation of N-acyl tetramic acids with an alkyl carboxylic acid using 1.3 equiv of DMAP (with 1.1 equiv of DCC) unexpectedly gave the 3-acyltetramic acid directly as a result of acyl migration induced by excess amounts of DMAP. On the other hand, N-unsubstituted, N-alkyl, and N-acyl tetramic acids with alkyl and aromatic carboxylic acids gave the O-acyl tetramic acids by using only 0.1 equiv of DMAP (with 1.1 equiv of DCC); these could be further rearranged to the acyl product by treatment with excess DMAP. The tautomeric equilibrium of these 3-acyltetramic acids in solution was found to strongly depend on the nitrogen substituent group (R(1)) rather than the 3-acyl group.  相似文献   
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