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91.
Betül Taşdelen Aysun Ergun Fikret Büyükkaya 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(2):573-575
DOTA-conjugated peptides, such as [DOTA0, Tyr3]ocreotide (DOTATOC) and [DOTA0, Tyr3]octreotate (DOTATATE) can be labeled with radionuclides such as 90Y, 177Lu and 111In at high specific activities. These radiolabelled somatostatin analogues are used for peptide receptor radionuclide therapy
(PRRT). Currently, radio-high performance liquid chromatography (radio-HPLC) and radio-thin layer chromatography (radio-TLC)
are the methods of choice for the analysis of the labeled compounds. In literature, radiochemical purity of the radiolabelled
DOTATATE was investigated using gradient reversed-phase radio-HPLC. However, these studies indicate long retention time of
the radiolabelled compound of 14.52 min. In our study, a new simple and rapid reversed-phase isocratic system enables the
radiochemical purity of the radiolabelled DOTATATE within a few minutes. 相似文献
92.
Betül Taşdelen 《Journal of Radioanalytical and Nuclear Chemistry》2011,290(2):283-287
Technetium-99m-sestamibi (99mTc-MIBI) is a small, lipophilic and cationic compound used for myocardial perfusion imaging. In addition, 99mTc-MIBI has been shown to be useful in identifying several types of tumors, such as breast, lung and thyroid cancers. The
high quality of this radiopharmaceutical and its uniformity are very important facts for application of this preparation in
clinical practice. The monograph for 99mTc-MIBI recommends at least 90% radiochemical purity (RCP) for clinical use. Various factors may influence the RCP of certain
reagent kits. Some of these include the amount of activity added to the reagent kit, heating time and the age of the formulated
kit. The effect of these factors on RCP of 99mTc-MIBI has been investigated using high performance liquid chromatography (HPLC) and instant thin layer chromatography. 相似文献
93.
Ta HP Berthelot K Coulary-Salin B Desbat B Géan J Servant L Cullin C Lecomte S 《Langmuir : the ACS journal of surfaces and colloids》2011,27(8):4797-4807
Many in vitro studies have pointed out the interaction between amyloids and membranes, and their potential involvement in amyloid toxicity. In a previous study, we generated a yeast toxic mutant (M8) of the harmless model amyloid protein HET-s((218-289)). In this study, we compared the self-assembling process of the nontoxic wild-type (WT) and toxic (M8) protein at the air-water interface and in interaction with various phospholipid monolayers (DOPE, DOPC, DOPI, DOPS and DOPG). We first demonstrate using ellipsometry measurements and polarization-modulated infrared reflection absorption spectroscopy (PMIRRAS) that the air-water interface promotes and modifies the assembly of WT since an amyloid-like film was instantaneously formed at the interface with an antiparallel β-sheet structuration instead of the parallel β-sheet commonly observed for amyloid fibers generated in solution. The toxic mutant (M8) behaves in a similar manner at the air-water interface or in bulk, with a fast self-assembling and an antiparallel β-sheet organization. The transmission electron microscopy (TEM) images established the fibrillous morphology of the protein films formed at the air-water interface. Second, we demonstrate for the first time that the main driving force between this particular fungus amyloid and membrane interaction is based on electrostatic interactions with negatively charged phospholipids (DOPG, DOPI, DOPS). Interestingly, the toxic mutant (M8) clearly induces perturbations of the negatively charged phospholipid monolayers, leading to a massive surface aggregation, whereas the nontoxic (WT) exhibits a slight effect on the membrane models. This study allows concluding that the toxicity of the M8 mutant could be due to its high propensity to interact with membranes. 相似文献
94.
天然石墨经过浓硫酸氧化处理,酚醛树脂包覆并高温碳化后形成具有核壳结构的碳包覆氧化天然石墨复合材料.采用扫描电子显微镜(SEM),透射电子显微镜(TEM),X射线衍射(XRD),激光显微拉曼光谱(Raman)等检测技术对氧化处理以及酚醛树脂热解碳包覆前后天然石墨材料的结构与形貌进行分析与表征.结果表明,氧化处理与适量的酚醛树脂热解碳包覆有效修复了天然石墨表面的一些缺陷结构,使其表面更为光滑.电化学测试结果显示,经过氧化处理与酚醛树脂热解碳包覆后天然石墨材料电化学性能得到明显提高.酚醛树脂包覆量为9%时,复合材料表现出最好的电化学性能,其首次放电比容量为434.0mAh·g-1,40次循环后,放电比容量保持在361.6mAh·g-1,而未经处理的天然石墨放电比容量仅为332.3mAh·g-1.该改性方法有效提高了天然石墨材料的比容量,对其进一步应用具有重要意义. 相似文献
95.
Le Thi Phuong Ngoc Nguyen Thanh Long 《Nonlinear Analysis: Theory, Methods & Applications》2011,74(18):7111-7125
Motivated by the recent known results about the solvability and existence of asymptotically stable solutions for nonlinear functional integral equations in spaces of functions defined on unbounded intervals with values in the n-dimensional real space, we establish asymptotically stable solutions for a nonlinear functional integral equation in the space of all continuous functions on R+ with values in a general Banach space, via a fixed point theorem of Krasnosel’skii type. In order to illustrate the result obtained here, an example is given. 相似文献
96.
We consider energy estimates for second order homogeneous hyperbolic equations with time dependent coefficients. The property
of energy conservation, which holds in the case of constant coefficients, does not hold in general for variable coefficients;
in fact, the energy can be unbounded as t → ∞ in this case. The conditions to the coefficients for the generalized energy conservation (GEC), which is an equivalence
of the energy uniformly with respect to time, has been studied precisely for wave type equations, that is, only the propagation
speed is variable. However, it is not true that the same conditions to the coefficients conclude (GEC) for general homogeneous
hyperbolic equations. The main purpose of this paper is to give additional conditions to the coefficients which provide (GEC);
they will be called as C
k
-type Levi conditions due to the essentially same meaning of usual Levi condition for the well-posedness of weakly hyperbolic
equations. 相似文献
97.
98.
Han KN Li CA Bui MP Pham XH Seong GH 《Chemical communications (Cambridge, England)》2011,47(3):938-940
We controlled the morphologies of zinc oxide (ZnO) nanostructures on single-walled carbon nanotube electrodes by an electrochemical deposition method and investigated the dependence of the electrocatalytic characteristics toward hydrazine on the different morphologies. ZnO nanorods provided high electrocatalytic activity with unique electrochemical behaviours, associated with the H(+) ion generated by the electro-oxidation of hydrazine. 相似文献
99.
Shiraki T Dawn A Le TN Tsuchiya Y Tamaru S Shinkai S 《Chemical communications (Cambridge, England)》2011,47(25):7065-7067
A thermo- and light-responsive system consisting of single-walled carbon nanotube and helical polysaccharide modified with poly(N-isopropylacrylamide) side-chains has been developed through supramolecular polymer wrapping. Coagulation of the complex can be induced by the external stimuli, which leads to a catch-and-release action of a porphyrin derivative. 相似文献
100.
Murat Taş Seval Çamur Yalçın Kılıç 《Journal of Thermal Analysis and Calorimetry》2011,103(3):995-1000
The complexes were synthesized by the reaction between sodium salt of p-aminosalicylic acid (PAS) and Cu(II) for 1 and corresponding ethylenediamine (en) or its derivatives for 2–6. The complexes were characterized by using elemental analyses, FT-IR, UV–Vis, magnetic moment measurements, and thermal analyses
techniques. In complex 1[Cu2(PA)4(H2O)2], two Cu(II) ions were found as bridged by four μ-O:O′ p-aminosalicylato (PA) ligands, forming a cage structure, and two aqua ligands to form dinuclear square-pyramidal geometry
around Cu(II) ions. In the complexes 2–6, the PA (anionic form of p-aminosalicylic acid) coordinated to Cu(II) ions as monodentate manner by using its oxygen atom of deprotonated carboxylic
acid and ethylenediamine derivatives coordinated to the Cu(II) ions in bidentate manner to form mononuclear octahedral complexes
[Cu(PA)2(L)2] (L = ethylendiamine, N,N-dimethylethylendiamine, N,N′-dimethylethylendiamine, N,N,N′,N′-tetramethylethylendiamine, and 1,3-propanediamine, for complexes 2, 3, 4, 5, and 6, respectively). In all the complexes OH and NH2 groups of PA ligands were not coordinated to metals. 相似文献