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排序方式: 共有555条查询结果,搜索用时 31 毫秒
41.
Yusuf Kurtulmus T. Tanyalçın Giray Bozkaya Ogˇuzhan Gündüz Ömür Çerçi Fatma Z. Kutay Biltan Ersöz 《Accreditation and quality assurance》2001,6(9-10):424-426
The aim of this study was to compare two immunoassay measurement methods, the ACS:180 Plus (Chiron Diagnostics) kit and the Immulite sPSA (DPC) kit. Method comparison analysis was performed according to EP9-A; approved guideline of NCCLS 51. Serum samples having a wide range of total prostate-specific antigen (PSA) concentrations were evaluated in split-sample analysis. F-test, t-test analysis and regression statistics were performed. In Deming regression analysis the coefficients were as follows; the slope=0.967; y-intercept=-0.148, r=0.989. An acceptable bias was seen since the systematical error was calculated to have a value less than the total allowable error calculated from biological variations. Non-parametric evaluation of the area under ROC curves for ACS:180 Plus and Immulite sPSA were 0.997 and 0.987, respectively. Diagnostic accuracy was at the level of p= 0.000 and no statistical difference was found between the two assay methods. 相似文献
42.
Gunjan Pandey Tasneem Fatma Sudha M. Cowsik Sneha Sudha Komath 《Journal of photochemistry and photobiology. B, Biology》2009,97(2):87-93
Recent research has shown that, like porphyrins, phycocyanin (PC) too can produce singlet oxygen upon excitation with the appropriate radiation and hence could be useful in photodynamic therapy (PDT) for cancer. Unlike porphyrins, PC has the advantage of being a non-toxic, non-carcinogenic, soluble protein. However, the challenge would be to target the fluorescent phycobiliprotein to malignant cells. We report here that the tumor-specific lectin, jacalin, binds PC specifically in a carbohydrate-independent manner and with affinities better than that for porphyrins. Hence the lectin could prove to be a useful carrier for targeted delivery of PC. The interaction involves both ionic and hydrophobic interactions and more than one contact site. 相似文献
43.
A series of homo‐, heterodinuclear and homotrinuclear copper(II) complexes containing a new Schiff base ligand and 1,10‐phenanthroline were synthesized. Based on results of elemental analyses, FTIR, 1H‐ and 13C‐NMR spectra, conductivity measurements and magnetic susceptibility measurements, the complexes had general compositions {[Cu(L)(H2O)M(phen)2](ClO4)2 [M = Cu(II), Mn(II), Co(II)]} and {[Cu3(L)2(H2O)2](ClO4)2}. The metal:L:phen ratio is 2:1:2 for the dinuclear copper(II) complexes and the metal:L ratio was 3:2 for the trinuclear copper(II) complex. The liquid–liquid extraction of various transition metal cations [Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Pb(II), Cd(II), Hg(II)] from the aqueous phase to the organic phase was carried out using the diimine–dioxime ligand. It was concluded that the ligand can effectively be used in solvent extraction of copper(II) from the aqueous phase to the organic phase. Furthermore, catalytic activitiy of the complexes for the disproportionation of hydrogen peroxide was also investigated in the presence of imidazole. Dinuclear copper(II)–manganese(II) complex has some similarity to manganese catalase in structure and activity. The interaction between these complexes and DNA has also been investigated by agarose gel electrophoresis; we found that the homo‐ and heterodinuclear copper complexes can cleave supercoiled pBR322 DNA to nicked and linear forms in the presence of H2O2. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
44.
This research work is concerned with the use of N‐benzoyl cyanoacetylhydrazine ( 3 ) in synthesizing several new heterocyclic compounds with potential biological activity, via its reaction with various chemical reagents. The synthesized derivatives have actually exhibited, upon screening, antibacterial and antifungal activities. 相似文献
45.
Emine Özge Karaca Mitat Akkoç Muhammad Nawaz Tahir Cengiz Arıcı Fatma İmik Nevin Gürbüz Sedat Yaşar İsmail Özdemir 《Tetrahedron letters》2017,58(36):3529-3532
A series of seven-membered ditopic ring-expanded N-heterocyclic carbene (dre-NHC) precursors, bearing sterically demanding and electron-rich aryl groups, were synthesised in moderate yields via the reaction of 1,2,4,5-tetrakis(bromomethyl)benzene with the corresponding N,N′-diarylformamidines in the presence of K2CO3 in acetonitrile under an air atmosphere. All new compounds were characterised by HRMS, NMR spectroscopy, and microanalysis, as well as X-ray crystallography for compound 1c. The development of an efficient catalytic system for the Suzuki-Miyaura coupling reaction of aryl chlorides with various boronic acids was also investigated using the in situ generated dre-NHC ligands. 相似文献
46.
Eno E. Ebenso Taner Arslan Fatma Kandemi̇rlı Ian Love Cemi̇l Öğretır Murat Saracoğlu Savıour A. Umoren 《International journal of quantum chemistry》2010,110(14):2614-2636
Density functional theory (DFT) at the B3LYP/6‐31G (d,p) and BP86/CEP‐31G* basis set levels and ab initio calculations using the RHF/6‐31G (d,p) methods were performed on four sulfonamides (namely sulfaacetamide (SAM), sulfapyridine (SPY), sulfamerazine (SMR), and sulfathiazole (STI)) used as corrosion inhibitors for mild steel in acidic medium to determine the relationship between molecular structure and their inhibition efficiencies (%IE). The order of inhibition efficiency obtained was SMR > SPY > STI > SAM which corresponded with the order of most of the calculated quantum chemical parameters namely EHOMO (highest occupied molecular orbital energy), ELUMO (lowest unoccupied molecular orbital energy), the energy gap (ΔE), the Mulliken charges on the C, O, N, S atoms, hardness (η), softness (S), polarizability (α), dipole moment (μ), total energy change (ΔET), electrophilicity (ω), electron affinity (A), ionization potential (I), the absolute electronegativity (χ), and the fraction of electrons transferred (ΔN). Quantitative structure activity relationship (QSAR) approach has been used and a correlation of the composite index of some of the quantum chemical parameters was performed to characterize the inhibition performance of the sulfonamides studied. The results showed that the %IE of the sulfonamides was closely related to some of the quantum chemical parameters but with varying degrees/order. The calculated %IE of the sulfonamides studied was found to be close to their experimental corrosion inhibition efficiencies. The experimental data obtained fits the Langmuir adsorption isotherm. The negative sign of the EHOMO values and other thermodynamic parameters obtained indicates that the data obtained supports physical adsorption mechanism. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 相似文献
47.
A separation/preconcentration procedure based on the coprecipitation of Pb(II), Fe(III), Co(II), Cr(III) and Zn(II) ions with copper(II)-N-benzoyl-N-phenyl-hydroxylamine complex (Cu-BPHA) has been developed. The analytical variables including pH, amount of BPHA, amount of copper(II) as carrier element, and sample volume were investigated for the quantitative recoveries of the elements. No interfering effects were observed from the concomitant ions when present in real samples. The recoveries of the analyte ions were in the range of 95–100%. The detection limits (3 s) for Pb(II), Co(II), Fe(III), Cr(III) and Zn(II) ions were found to be 2.3, 0.7, 0.7, 0.3 and 0.4 µg L?1, respectively. The validation of the procedure was performed by the analysis of CRM (SRM NIST-1547 peach leaves and LGC6019 river water) standard reference materials. The method was applied to the determination of the analytes in real samples including natural waters, hair, urine, soil, sediment and peritoneal fluids samples etc., and good results were obtained (relative standard deviations <4%, recoveries >95%). 相似文献
48.
Fatma Karipcin Bülent Dede Mustafa Cengiz 《Russian Journal of Inorganic Chemistry》2010,55(4):530-540
Four different types of new ligands Ar[COC(NOH)R]
n
(Ar=biphenyl, n = 1 H2L1; Ar=biphenyl, n = 2 H4L2; Ar=diphenylmethane, n = 1 H2L3; Ar=diphenylmethane, n = 2 H4L4; R=2-amino-4-chlorophenol in all ligands) have been obtained from 1 equivalent of chloroketooximes Ar[COC(NOH)Cl]
n
(HL1-H2L4) and 1 equivalent of 2-amino-4-chlorophenol (for H2L1 and H2L3) or 2 equivalent of 2-amino-4-chlorophenol (for H4L2 and H4L4). (Mononuclear or binuclear cobalt(II), nickel(II), copper(II) and zinc(II) complexes were synthesized with these ligands.)
These compounds have been characterized by elemental analyses, AAS, infra-red spectra and magnetic susceptibility measurements.
The ligands have been further characterized by 1H NMR. The results suggest that the dinuclear complexes of H2L1 and H2L3 have a metal:ligand ratio of 1:2; the mononuclear complexes of H4L2 and H4L4 have a metal:ligand ratio of 1:1 and dinuclear complexes H4L2 and H4L4 have a metal:ligand ratio of 2:1. The binding properties of the ligands towards selected transition metal ions (MnII, CoII, NiII, CuII, ZnII, PbII, CdII, HgII) have been established by extraction experiments. The ligands show strong binding ability towards mercury(II) ion. In addition,
the thermal decomposition of some complexes is studied in nitrogen atmosphere. 相似文献
49.
Zarife Sibel ahin Fatma Sevindi Hasan budak amil Ik 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(10):m314-m318
The title compounds, trans‐bis(trans‐cyclohexane‐1,2‐diamine)bis(6‐methyl‐2,2,4‐trioxo‐3,4‐dihydro‐1,2,3‐oxathiazin‐3‐ido)copper(II), [Cu(C4H4NO4S)2(C6H14N2)2], (I), and trans‐diaquabis(cyclohexane‐1,2‐diamine)zinc(II) 6‐methyl‐2,2,4‐trioxo‐3,4‐dihydro‐1,2,3‐oxathiazin‐3‐ide dihydrate, [Zn(C6H14N2)2(H2O)2](C4H4NO4S)2·2H2O, (II), are two‐dimensional hydrogen‐bonded supramolecular complexes. In (I), the CuII ion resides on a centre of symmetry in a neutral complex, in a tetragonally distorted octahedral coordination environment comprising four amine N atoms from cyclohexane‐1,2‐diamine ligands and two N atoms of two acesulfamate ligands. Intermolecular N—H...O and C—H...O hydrogen bonds produce R22(12) motif rings which lead to two‐dimensional polymeric networks. In contrast, the ZnII ion in (II) resides on a centre of symmetry in a complex dication with a less distorted octahedral coordination environment comprising four amine N atoms from cyclohexane‐1,2‐diamine ligands and two O atoms from aqua ligands. In (II), an extensive two‐dimensional network of N—H...O, O—H...O and C—H...O hydrogen bonds includes R21(6) and R44(16) motif rings. 相似文献
50.
In this paper we study the problem of optimization over an integer efficient set of a Multiple Objective Integer Linear Stochastic Programming problem. Once the problem is converted into a deterministic one by adapting the $2$ -levels recourse approach, a new pivoting technique is applied to generate an optimal efficient solution without having to enumerate all of them. This method combines both techniques, the L-shaped method and the combined method developed in Chaabane and Pirlot (J Ind Manag Optim 6:811–823, 2010). A detailed didactic example is given to illustrate different steps of our algorithm. 相似文献