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51.
Sunny 《程序员》2008,(6):20-23
四年前,李新科的汇众益智刚刚起步,他根据全国游戏产业的现状率先创建了“游戏学院”,四年后的今天,已经进入成熟期的汇众益智又将迎来哪些新的挑战?未来将有哪些进一步的规划呢?为此,本刊特别采访了汇众益智的总裁李新科先生,他将从汇众益智这几年的发展历程、教育品牌塑造以及教育本身等三个方面带领我们一起回顾汇众益智走过的路。  相似文献   
52.
Poly-γ-glutamic acid (PGA) is one of the bioactive compounds found in cheonggukjang, a fast-fermented soybean paste widely utilized in Korean cooking. PGA is reported to have a number of beneficial health effects, and interestingly, it has been identified as a possible anti-cancer compound through its ability to promote apoptosis in cancer cells, although the precise molecular mechanisms remain unclear. Our findings demonstrate that PGA inhibits the pro-proliferative functions of the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA), a known chemical carcinogen in HT-29 human colorectal cancer cells. This inhibition was accompanied by hallmark apoptotic phenotypes, including DNA fragmentation and the cleavage of poly (ADP-ribose) polymerase (PARP) and caspase 3. In addition, PGA treatment reduced the expression of genes known to be overexpressed in colorectal cancer cells, including cyclooxygenase 2 (COX-2) and inducible nitric oxide synthase (iNOS). Lastly, PGA promoted activation of 5'' adenosine monophosphate-activated protein (AMPK) in HT-29 cells. Taken together, our results suggest that PGA treatment enhances apoptosis in colorectal cancer cells, in part by modulating the activity of the COX-2 and AMPK signaling pathways. These anti-cancer functions of PGA make it a promising compound for future study.  相似文献   
53.
The synthesis and characterization of a novel star comprising eight allyl-terminated polyisobutylene (PIB) arms radiating from a calix[8]arene core is described. The synthesis was accomplished by a core-first method, by inducing the living polymerization of isobutylene (IB) by a suitably functionalized calix[8]arene initiator (1) in conjunction with BCl3-TiCl4 coinitiators, and terminating the growth of the living PIB arms by allyltrimethylsilane. The relative concentrations of BCl3 and TiCl4 are critical for the synthesis of well-defined 8-arm stars. Characterization of the products (which included triple detector GPC studies and 1H NMR spectroscopy) indicated quantitative allylation. A mechanism which summarizes the experimental observations is proposed. Received: 17 July 1997/Revised version: 11 September 1997/Accepted: 19 September 1997  相似文献   
54.
55.
The major problem facing the development of a small diameter vascular graft (<5 rnm diameter) to be used for the replacement of a coronary artery is thrombogenicity at the interface. When blood comes in contact with an artificial surface, the initial event occurring is the adsorption of plasma proteins on the surface [1, 2], followed by adhesion of platelets and activation of the clotting mechanism resulting in thrombus formation [3,4]. The concentration of the various proteins adsorbed is largely dependent on the surface properties of the material.  相似文献   
56.
Reaction of C60 fullerene with dialkyl bromomalonate (where the alkyl groups consist of short-, medium-, and long-saturated chains or unsaturated long chains) in the presence of sodium hydride gives [6,6]-bridged mono-adducts of methanofullerene. The spectroscopic properties of such fullerenoid lipids are reported.  相似文献   
57.
Major challenges to chimeric antigen receptor (CAR) T cell therapies include uncontrolled immune activity, off-tumor toxicities and tumor heterogeneity. To overcome these challenges, we engineered CARs directed against small molecules. By conjugating the same small molecule to distinct tumor-targeting antibodies, we show that small molecule specific-CAR T cells can be redirected to different tumor antigens. Such binary switches allow control over the degree of CAR T cell activity and enables simultaneous targeting of multiple tumor-associated antigens. We also demonstrate that ultraviolet light-sensitive caging of small molecules blocks CAR T cell activation. Exposure to ultraviolet light, uncaged small molecules and restored CAR T cell-mediated killing. Together, our data demonstrate that a light-sensitive caging system enables an additional level of control over tumor cell killing, which could improve the therapeutic index of CAR T cell therapies.  相似文献   
58.
Nanosized cuprous oxide filler particles (nCOP) with octahedral morphology were synthesized through hydrazine reduction method and were used to develop a novel nanocomposites based on epoxy resin. The morphology of epoxy–nCOP nanocomposites were analyzed using transmission electron microscopy and scanning electron microscopy. Differential scanning calorimetry analysis showed that the cure reaction rate of epoxy was found to increase with the addition of the nCOP and a plausible cure reaction mechanism was suggested. The activation energy required for the cure reaction reduced by 22% and 13% at the initial (E1) and final stage (E2) of the cure, respectively, by the incorporation of 3 phr nCOP. It was also shown that the kinetically controlled parts of reaction could be expressed well by Kamal's phenomenological model while end of curing process could not be completely expressed by this model as there it was diffusion controlled. The influence of nCOP on glass transition temperature (Tg), mechanical properties, and thermal stability of epoxy matrix was also investigated and the results showed that better characteristics were observed in presence of 3 phr nCOP loading. POLYM. ENG. SCI., 55:2293–2306, 2015. © 2015 Society of Plastics Engineers  相似文献   
59.
Arising from spontaneous aspartic acid (Asp) isomerization or asparagine (Asn) deamidation, isoaspartic acid (isoAsp, isoD, or beta-Asp) is a ubiquitous nonenzymatic modification of proteins and peptides. Because there is no mass difference between isoaspartyl and aspartyl species, sensitive and specific detection of isoAsp, particularly in complex samples, remains challenging. Here we report a novel assay for Asp isomerization by isotopic labeling with (18)O via a two-step process: the isoAsp peptide is first specifically methylated by protein isoaspartate methyltransferase (PIMT, EC 2.1.1.77) to the corresponding methyl ester, which is subsequently hydrolyzed in (18)O-water to regenerate isoAsp. The specific replacement of (16)O with (18)O at isoAsp leads to a mass shift of 2 Da, which can be automatically and unambiguously recognized using standard mass spectrometry, such as collision-induced dissociation (CID), and data analysis algorithms. Detection and site identification of several isoAsp peptides in a monoclonal antibody and the β-delta sleep-inducing peptide (DSIP) are demonstrated.  相似文献   
60.
Sunny 《程序员》2008,(8):28-30
中国游戏产业在学习国外先进的游戏开发经验和技术的同时,国外的一些游戏公司及相关产品也正积极地走近中国。Emergent、唯晶科技、Scaleform就是在这种背景下走到了一起。《游戏创造》对话栏目有机会请到三方的相关负责人就他们之间的合作心得以及产品未来技术发展的方向作些介绍。  相似文献   
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