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81.
82.
Conclusions Patients suffering from lung cancer exhibit increased serum levels of Cr, Co, Ag, Au, Zn and Fe. Serum concentrations of Se and Rb are found to vary within normal levels.Zinc concentrations in the blood serum of Carcinoma planoepitheliale patients do not deviate from normal values, whereas those of Carcinoma anaplasticum and Adenocarcinoma subjects are significantly increased.Compared to the reference tissue material, Co and Se occur at increased concentrations, while Ag, Cr and Fe contents show decreased values in the tumor tissue. In the case of Au, Rb and Zn no significant changes are observed.
Verhalten von Spurenelementen bei Lungenkrebs相似文献
83.
Barałkiewicz D 《Talanta》2002,57(1):105-114
An analytical method for the determination of glutamic acid by the sequential perturbation caused by different amounts of glutamic acid on the oscillating chemical system involving the Cu(II)-catalyzed oscillating reaction between hydrogen peroxide and sodium thiocyanate in an alkaline medium is proposed. The method relies on the linear relationship between the changes in the oscillation amplitude of the chemical system and the concentration of glutamic acid. The reaction is implemented in a continuous-flow stirred-tank reactor, and changes in the oscillation amplitude on each perturbation are proportional to the glutamic acid concentration. The use of the analyte pulse perturbation (APP) technique permits sequential determinations on the same oscillating system owing to the expeditiousness with which the steady state is regained after each perturbation. The dynamic range lies between 2.5x10(-6) and 3.2x10(-4) M of glutamic acid, with the regression coefficient is 0.9987. The precision is excellent (less than 0.68% as relative standard deviation (R.S.D.)). Some aspects of the potential mechanism of action of glutamic acid on the oscillating system are discussed. 相似文献
84.
Janusz Slawinski Wlodzimierz Puzyna Danuta Slawinska 《Photochemistry and photobiology》1978,28(1):75-81
Abstract— Photo-irradiation of aqueous basic solutions of soil humic acids and synthetic melanins with UV and visible light (Λ > 320 nm) under oxygen or nitrogen atmospheres generates electronic exicted states and radicals. These processes give rise to a long-lived chemiluminescence with emission maxima at 480–500, 570 and 615–650 nm, as well as a paramagnetic resonance (EPR) signal with g-value at 2.006 and ΔH~ 3Gs. Chemiluminescence intensity and EPR signals follow multistep kinetics. An increase of the ratio of OD at 260/400 nm and 400/600 nm and a decrease of amplitude of an EPR signal after prolonged photo-irradiation were observed. Long irradiation also causes a decrease of fluorescence intensity bands with maxima at 535 nm and 495 nm (Λex 480 and 400 nm, respectively), and an increase of the short wavelength band with a maximum at 450 nm (Λex 260 nm). The data indicate that a complex chain of reactions initiated by reactive species leads to the degradation of the aromatic core of the polymers. Oxygen efficiently enhances the chemiluminescence intensity and the rate of photodegradation. The mechanism of photodegradative oxidation and chemiluminescence probably involves an energy transfer process and singlet oxygen formation. The possibility of its occurrence in nature and its significance are discussed. 相似文献
85.
Danuta Jarecka Anita Besch Hans-Hartwig Otto 《Monatshefte für Chemie / Chemical Monthly》2003,5(7):901-908
The reaction of methyl saccharin-2-acetate with hydrazine gave no 3-hydrazino derivative of saccharin as reported in literature, but yielded with ring opening the benzohydrazide derivative. The analogue reaction was observed when saccharin-2-(2-propionate) was reacted with hydrazine. Furthermore, using an excess of hydrazine, the ester group was transformed into the carbohydrazide too. All hydrazides were fully characterized as hydrazones by reactions with different ketones. The 3-thioxo compounds were prepared by reactions with P2s5, but the yield was improved by using Lawesson’s reagent. No attack at the ester group was observed. Finally, reactions of the saccharin-2-carboxylate with some amino acids gave substituted benzamides by attack at position 3 and ring opening. In none of the reactions of the saccharin derivatives with nitrogen nucleophiles a formal substitution of the 3-oxo group was observed. 相似文献
86.
Andrzej Gzella Danuta Brzda ukasz Koroniak Maria D. Rozwadowska 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(8):o503-o506
In the two title optically active tetrahydroisoquinoline derivatives, namely 3‐hydroxymethyl‐4‐phenyl‐1,2,3,4‐tetrahydroisoquinolin‐2‐ium bromide methanol hemisolvate, C16H18NO+·Br?·0.5CH3OH, (IIb), and 2‐formyl‐3‐hydroxymethyl‐4‐phenyl‐1,2,3,4‐tetrahydroisoquinoline, C17H17NO2, (III), the absolute configurations have been confirmed as 3R,4R by structure refinement using Bijvoet‐pair reflections. The hydroxymethyl and phenyl groups in (IIb) are oriented in equatorial and pseudo‐equatorial positions, respectively, whereas in (III), the corresponding groups are in axial and pseudo‐axial positions, respectively; the hydroxymethyl and phenyl groups are trans with respect to one another in both structures. The heterocyclic rings in (IIb) and (III) adopt envelope conformations inverted with respect to each other. In both structures, the molecules are linked through hydrogen bonds. 相似文献
87.
88.
Wróbel D Boguta A Mazurkiewicz P 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2003,59(12):2841-2854
Subphthalocyanine and subnaphthalocyanine dyes and their mixture were investigated by means of the spectroscopic and photoelectric methods. Absorption, fluorescence, steady-state and time-resolved photothermal measurements for the dyes and their mixture were done in order to get information about the radiative and non-radiative deactivation processes as competetive processes to charge separation. It was shown that energy transfer between the dyes improved the photocurrent generation in photoelectrochemical cells (PEC) based on In(2)O(3) and SnO(2) as an electrode. The possible participation of the dye triplet states in non-radiative processes was discussed. 相似文献
89.
Nikodem Ku
nik Jan Zawadiak Danuta Gilner Angelika Wickol Pawe Wagner Maciej Kubicki 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(9):o549-o550
The title compound, C26H30O4, is one of the first alkyl bis‐peroxides to be structurally characterized. The molecule lies on a centre of inversion and therefore the terminal phenyl rings are parallel. Although there are three aromatic rings in the molecule, the C—O—O—C torsion angle of 163.10 (10)° is close to the value found in Me3COOCMe3. 相似文献
90.
Danuta Frackowiak Surat Hotchandani G. Bialek-Bylka Roger M. Leblanc 《Photochemistry and photobiology》1985,42(5):567-572
Abstract— Photoacoustic spectra (PAS) of biliproteins, namely, R-phycoerythrin (PE) and C-phycocyanin (PC) and their mixture in anisotropic and isotropic polyvinylalcohol (PVA) films were measured under the illumination with polarized and natural light. Also samples in deuterated PVA were investigated. The yields of fluorescence of various chromophores of investigated biliproteins were obtained from PAS, absorption, fluorescence and fluorescence lifetime measurements. The deuteration of samples causes different changes in thermal deactivation of excitation of various chromophores. Ratios of PAS to absorption of the light polarized parallel and perpendicular to the direction of film stretching are different. The PAS amplitude of deuterated samples is higher than that for undeuterated. 相似文献