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21.
通过针对高三专题复习的教学实验,分析当前主流教学模式存在的问题,并提出了对教学模式改革的看法.  相似文献   
22.
Inspired by the diverse protein‐based structures and materials in organisms, proteins have been expected as promising biological components for constructing nanomaterials toward various applications. In numerous studies protein‐based nanomaterials have been constructed with the merits of abundant bioactivity and good biocompatibility. However, self‐assembly of proteins as a dominant approach in constructing anticancer nanodrugs has not been reviewed. Here, we provide a comprehensive account of the role of protein self‐assembly in fabrication, regulation, and application of anticancer nanodrugs. The supramolecular strategies, building blocks, and molecular interactions of protein self‐assembly as well as the properties, functions, and applications of the resulting nanodrugs are discussed. The applications in chemotherapy, radiotherapy, photodynamic therapy, photothermal therapy, gene therapy, and combination therapy are included. Especially, manipulation of molecular interactions for realizing cancer‐specific response and cancer theranostics are emphasized. By expounding the impact of molecular interactions on therapeutic activity, rational design of highly efficient protein‐based nanodrugs for precision anticancer therapy can be envisioned. Also, the challenges and perspectives in constructing nanodrugs based on protein self‐assembly are presented to advance clinical translation of protein‐based nanodrugs and next‐generation nanomedicine.  相似文献   
23.
陈振初  吴千里  黄宪 《有机化学》1983,3(3):188-190228
亚烃基丙二酸亚异丙酯与格氏试剂的共轭加成和α-烃化串联反应提供了一种合成不对称双取代丙二酸亚异丙酯的新方法。由于不对称双取代丙二酸亚异丙酯易水解失羧和醇解失羧转化成相应的羧酸及酯,因此本法也是合成α-及β-高取代的羧酸及其酯的有效方法。  相似文献   
24.
Russian Journal of Physical Chemistry A - Mn2O3 microsheets were successfully synthesized via a facile electrospinning method followed by post-calcination process. MnO particles, Mn3N2/MnO/C...  相似文献   
25.
复合微球的制备、性能及应用   总被引:14,自引:0,他引:14  
本文综述了复合微球的制备、性能及其应用,并对其发展趋势作了展望.  相似文献   
26.
Geotrichum sp. lipase modified with a combined method composed of crosslinking and bioimprinting was employed to selectively hydrolyze waste fish oil for enrichment of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in glycerides. Crosslinked polymerization by monomer (polyethylene glycol 400 dimethyl acrylate), crosslinker (trimethylolpropane trimethylacrylate), and photoinitiator (benzoin methyl ether) coupled to bioimprinting using palmitic acid as imprint molecule, resulted in much more effective enzyme preparation used in aqueous hydrolysis reaction. Since the crosslinked polymerization modification maintained bioimprinted property and gave good dispersion of enzyme in reaction mixture, the crosslinked bioimprinted enzyme exhibited higher hydrolysis temperature, enhanced specific activity, shorter hydrolysis time, and better operational stability compared to free lipase. Crude fish oil was treated at 45 °C with this crosslinked bioimprinted lipase for 8 h, and 46% hydrolysis degree resulted in the production of glycerides containing 41% of EPA and DHA (EPA+DHA), achieving 85.7% recovery of initial EPA and DHA. The results suggested that bioimprinted enzymes did not lose their induced property in aqueous environment when prepared according to the described crosslinking–bioimprinting method. It could also be seen that the crosslinked bioimprinted lipase was effective in producing glycerides that contained a higher concentration of polyunsaturated fatty acid with better yield.  相似文献   
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28.
Treatment of N,N‐dichloroperfluoroalkanesulfonylamines with sulfur powder at room temperature gave the title products RfSO2N=SCl2 in good yields. They reacted readily with dimethyl sulfoxide, chloral, DMF, benzophenone, and similar compounds to form to corresponding imines RfSO2N=YR1R2 (Y: S, C). A reaction mechanism, one involving formation of a four‐membered intermediate, is proposed. © 1999 John Wiley & Sons, Inc. Heteroatom Chem 10: 41–48, 1999  相似文献   
29.
徐千里 《数学杂志》1999,19(4):431-436
本文利用奇点理论与Bendixson定理对淋病扩散模型进行了定性分析,给出了可行平衡点附近,特别是高阶平衡点附近轨线的定性结构,研究了可行平衡点的全局渐近稳定性,得到了完整的结果。  相似文献   
30.
Six new arenetelluronic triorganotin esters, namely (R3Sn)4[ArTe(μ‐O)(OH)O2)]2 (Ar = Ph, R = Me: 1 , R = Ph: 2 ; Ar = 3‐Me‐Ph, R = Me: 3 , R = Ph: 4 , Ar = 3‐Cl‐Ph, R = Me: 5 , R = Ph: 6 ), were prepared by treating arenetelluronic acids with the corresponding R3SnCl (R = Me, Ph) with potassium hydroxide in methanol. All complexes were characterized by elemental analysis, FT‐IR, NMR (1H, 13C, 119Sn) spectroscopy, and X‐ray crystallography. The structural analyses indicate that these complexes are isostructural as Sn4Te2 moiety, in which the Te22‐O)2 units are situated in the center and each Te atom is coordinated with two OSnR3 groups on the side. Complexes 1 , 3 , and 5 show one‐dimensional chain and two‐dimensional network supramolecular structures by intermolecular C H···O or C H···Cl interactions. The antitumor activities of these complexes reveal that most arenetelluronic triorganotin esters have powerful antitumor activities with certain regularity.  相似文献   
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