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91.
据Mahlanobis距离判别法,利用计算机多元统计判别程序,对14例甲亢思者和21例健康人的血清中锌、铁、铜、锰、镁和锶等元素浓度差异进行分类判别研究。选择锌、铁、钙、锶作判别特征参量时,患者和健康人的分类准确率为100%,服碘前与服碘后的甲亢患者分类准确率为92.7%,分类研究指出,甲亢患者血清中的铁和锶浓度高于健康人,经服碘治疗后,患者血清中上述元素浓度降低与健康人相近。 相似文献
92.
Xiaoling Bao Jianhong Liu Qingshu Zheng Wei Pei Yimei Yang Yanyun Dai Tao Tu 《中国化学快报》1990,30(12):2266-2270
A novel protocol allowing convenient and highly selective visual recognition of melamine in raw milk via selective metallo-hydrogel formation at a concentration as low as 10 ppm without any tedious pretreatment has been developed. 相似文献
93.
Hiroshi Ikeda Takumi Sugiyama Akihiko Ueno 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):83-87
A new chemosensor for larger guests was prepared. The new chemosensor bears hydrophobic units at the primary hydroxy side
and a dansyl unit at the secondary hydroxy side of β-cyclodextrin. Due to the hydrophobic units, the new chemosensor is sensitive
to large or slender guests such as SDS and insensitive to 1-adamantanol, which is a good guest for the natural β-CD. 相似文献
94.
Teresa Borowiak Maciej Kubicki Grzegorz Dutkiewicz Marek Pietraszkiewicz Oksana Pietraszkiewicz 《Journal of inclusion phenomena and macrocyclic chemistry》2005,51(3-4):181-189
Two newly identified supramolecular structures arise from self-assembly of the macrocyclic 1,5,9,18,22,26- hexaaza[11.11]-p-cyclophane salts with o-nitrophenol (C28H50N6)4+·4(C6H4NO2O)− (1) and with HCl (C28H52N6)6+·6Cl-·4H2O (2). In both cases two-dimensional supramolecular sheets are formed. 相似文献
95.
Molecular imprinting is a template polymerization technique that can easily provide synthetic polymers capable of molecular recognition for given target molecules. In addition to their highly specific recognition ability, we are attempting to introduce signaling functions to molecularly imprinted polymers, enabling them to respond according to specific binding events. Some of our work regarding such signaling molecularly imprinted polymers is presented here, including molecularly imprinted polymers that induce spectral shifts of target compounds because of binding. Such compounds include hydrogen-bonding-based fluorescent imprinted polymers and metalloporphyrin-based signaling molecularly imprinted polymers. 相似文献
96.
Klärner FG Lobert M Naatz U Bandmann H Boese R 《Chemistry (Weinheim an der Bergstrasse, Germany)》2003,9(20):5036-5047
The novel trimethylene-bridged clips 3 and 4 have been synthesized by using repetitive stereoselective Diels-Alder reactions of the benzo- and naphthobismethylenenorbornenes 8 and 19 as dienes and norbornadiene 9 as bisdienophile, and subsequent dehydrogenation of the primary cyclobisadducts 10 and 20 by using 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). Clips 3 and 4 serve as receptors for a variety of electron-deficient neutral and cationic aromatic substrates, comparable to the molecular tweezers 1 and 2. The thermodynamic parameters of the complex formation, K(a) and DeltaG, were determined by (1)H NMR titration experiments and, in the case of the highly stable complex TCNB 32@4, by the use of isothermal titration microcalorimetry. The finding that clip 4 forms more stable complexes than 3 can be explained by the larger van der Waals contact surfaces of the naphthalene sidewalls in 4 compared to the corresponding benzene systems in 3. In the complexes with 4 as receptor, the plane of each aromatic substrate molecule is calculated to be oriented almost parallel to the naphthalene sidewalls. However, in the complexes of tweezers 2, the substrate is usually oriented parallel to the central naphthalene spacer unit. Due to the more open topology of 4, most complexes were calculated to consist of two or more equilibrating noncovalent conformers. 相似文献
97.
98.
Molt O Rübeling D Schäfer G Schrader T 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(17):4225-4232
Host molecule 1 displays a high affinity in water towards catecholamines and especially related structures such as beta-blockers with extended aromatic pi-faces (up to 7x10(3) M(-1) for each single complexation step or 5x10(7) M(-2) for both steps). The amphiphilic structural design leads to an extensive self-association of host molecules through their aromatic flanks. Above a cmc (critical micelle concentration) of 3x10(-4) M, host 1 forms micelles that produce a favorable microenvironment for hydrophobic interactions with the included guest molecules. Electrostatic attraction of the ammonium alcohol by the phosphonate anions is thus combined with hydrophobic contributions between the aromatic moieties. Ionic hydrogen bonds with polar OH or NH groups of the guest enforce the non-covalent interactions, and finally lead to increased specificity. Both its affinity and its selectivity towards adrenergic receptor substrates are greatly enhanced if the receptor molecule 1 is transferred from water into a lipid monolayer. Catecholamines and beta-blockers lead to drastically different effects at concentrations approaching the micromolar regime. Especially beta-blockers with minute structural changes can be easily distinguished from each other. In both cases, extensive hydrophobic interactions with a self-associated and/or self-organized microenvironment are largely responsible for the observed high efficiency and specificity. 相似文献
99.
综述了近8年来液相平行合成和组合合成中应用的不同技术, 包括可溶性载体、氟合成技术、离子液体、固相试剂树脂以及低聚乙烯二醇(OEG)衍生物的应用等几方面内容. 论述了它们的基本原理以及相关的应用实例, 并着重强调了目标化合物的分离纯化方法. 相似文献
100.
Stoikov I. I. Gafiullina L. I. Ibragimova D. Sh. Antipin I. S. Konovalov A. I. 《Russian Chemical Bulletin》2004,53(6):1172-1180
New calix[4]arenes, di- and tetrasubstituted at the lower rim, with different functional groups were synthesized. They were studied as carriers of a series of dicarboxylic and -hydroxycarboxylic acids through a liquid impregnated membrane. The calix[4]arenes under study are capable of molecular recognition of oxalic acid in the series of structurally similar dicarboxylic and -hydroxycarboxylic acids. The regularities found make it possible to change purposefully the receptor ability of 1,3-disubstituted calix[4]arenes by variation of the nature of substituents. 相似文献