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41.
Gilda M. Iova Horia Calniceanu Adelina Popa Camelia A. Szuhanek Olivia Marcu Gabriela Ciavoi Ioana Scrobota 《Molecules (Basel, Switzerland)》2021,26(5)
Background: There is a growing interest in the correlation between antioxidants and periodontal disease. In this study, we aimed to investigate the effect of oxidative stress and the impact of two antioxidants, curcumin and rutin, respectively, in the etiopathology of experimentally induced periodontitis in diabetic rats. Methods: Fifty Wistar albino rats were randomly divided into five groups and were induced with diabetes mellitus and periodontitis: (1) (CONTROL)—control group, (2) (DPP)—experimentally induced diabetes mellitus and periodontitis, (3) (DPC)—experimentally induced diabetes mellitus and periodontitis treated with curcumin (C), (4) (DPR)—experimentally induced diabetes mellitus and periodontitis treated with rutin (R) and (5) (DPCR)—experimentally induced diabetes mellitus and periodontitis treated with C and R. We evaluated malondialdehyde (MDA) as a biomarker of oxidative stress and reduced glutathione (GSH), oxidized glutathione (GSSG), GSH/GSSG and catalase (CAT) as biomarkers of the antioxidant capacity in blood harvested from the animals we tested. The MDA levels and CAT activities were also evaluated in the gingival tissue. Results: The control group effect was statistically significantly different from any other groups, regardless of whether or not the treatment was applied. There was also a significant difference between the untreated group and the three treatment groups for variables MDA, GSH, GSSG, GSH/GSSG and CAT. There was no significant difference in the mean effect for the MDA, GSH, GSSG, GSH/GSSG and CAT variables in the treated groups of rats with curcumin, rutin and the combination of curcumin and rutin. Conclusions: The oral administration of curcumin and rutin, single or combined, could reduce the oxidative stress and enhance the antioxidant status in hyperglycemic periodontitis rats. 相似文献
42.
Ancu?a Balla Cristina Marcu Damian Axente Gheorghe Borodi Diana Laz?r 《Central European Journal of Chemistry》2012,10(6):1817-1823
The reduction of H2SO4 to SO2 occurs with a relatively good efficiency only at high temperatures, in the presence of catalysts. Some experimental results, regarding conversion of sulfuric acid (96 wt.%) to sulfur dioxide and oxygen, are reported. The reduction has been performed at 800 ?C 900°C and atmospheric pressure, in a tubular quartz reactor. The following commercial catalysts were tested: Pd/Al2O3 (5 wt.% and 0.5 wt.% Pd), Pt/Al2O3 (0.1 wt.% Pt) and ??-Fe2O3. The fresh and spent catalysts were characterized by X-Ray diffraction and BET method. The highest catalytic activity was determined for 5 wt.% Pd/Al2O3, a conversion of 80% being obtained for 5 hours time on stream, at 9 mL h?1 flow rate of 96 wt.% H2SO4. A conversion of 64% was determined for 0.5 wt.% Pd/Al2O3 and 0.1 wt.% Pt/Al2O3. For ??-Fe2O3, a less expensive catalyst, a conversion of 61% for about 60 hours was obtained. 相似文献
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The extraction of dioxouranium(VI) species from acidic aqueous solutions into benzene, in the presence of dialkyldithiophosphoric acids occurs with moderate partition coefficients, increasing with the length of the alkyl chain. The mechanism involves the formation of neutral [UO2[S2P(OR)2]2] species soluble in benzene, the partition is strongly affected by complexation in the aqueous phase, when the alkyl chain is short. Distribution coefficients and extraction constants have been determined under various conditions. 相似文献
45.
The critical exponent ν of the mass gap is calculated for a one-dimensional, Z3 symmetric quantum chain. Using the strong coupling expansion and finite-size scaling it is shown that ν varies continuously from . 相似文献
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47.
Time-resolved fluorescence spectra of arterial fluorescent compounds: reconstruction with the Laguerre expansion technique 总被引:2,自引:0,他引:2
The time-resolved fluorescence spectra of the main arterial fluorescent compounds were retrieved using a new algorithm based on the Laguerre expansion of kernels technique. Samples of elastin, collagen and cholesterol were excited with a pulsed nitrogen laser and the emission was measured at 29 discrete wavelengths between 370 and 510 nm. The expansion of the fluorescence impulse response function on the Laguerre basis of functions was optimized to reproduce the observed fluorescence emission. Collagen lifetime (5.3 ns at 390 nm) was substantially larger than that of elastin (2.3 ns) and cholesterol (1.3 ns). Two decay components were identified in the emission decay of the compounds. For collagen, the decay components were markedly wavelength dependent and hydration dependent such that the emission decay became shorter at higher emission wavelengths and with hydration. The decay characteristics of elastin and cholesterol were relatively unchanged with wavelength and with hydration. The observed variations in the time-resolved spectra of elastin, collagen and cholesterol were consistent with the existence of several fluorophores with different emission characteristics. Because the compounds are present in different proportions in healthy and atherosclerotic arterial walls, characteristic differences in their time-resolved emission spectra could be exploited to assess optically the severity of atherosclerotic lesions. 相似文献
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49.
M. Rusu Gh. Marcu D. Rusu C. Roşu A.-R. Tomsa 《Journal of Radioanalytical and Nuclear Chemistry》1999,242(2):467-472
Two tris(oxouranium)-substituted Keggin and Dawson sandwich-type tungstophosphate heteropolyanions Na12[(UO)3(H2O)6(PW9O34)2]·21 H2O (1) and Na18[(UO)3(H2O)6(P2W15O56)2]·27 H2O (2) have been prepared by reaction of uranium sulphate with [PW9O34]9− and [P2W15O56]12−, respectively, in aqueous media at 4.7 pH. The products were characterized by elemental and thermal analyses, IR, UV-Vis
spectroscopy and magnetical susceptibility. The results of these studies suggest that the compounds obtained from Keggin and
Dawson trilacunary anions are 2∶3 sandwich-type complexes and both exhibit a square antiprismatic stereochemistry for uranium(IV)
with retention of polyoxometallate parent structure. 相似文献
50.
Guy Mayer Zohar Shpilt Shachar Bressler Orly Marcu Prof. Ora Schueler-Furman Prof. Edit Y. Tshuva Prof. Assaf Friedler 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(45):10240-10249
Intrinsically disordered regions in proteins (IDRs) mediate many disease-related protein–protein interactions. However, the unfolded character and continuous conformational changes of IDRs make them difficult to target for therapeutic purposes. Here, we show that a designed peptide based on the disordered p53 linker domain can be used to target a partner IDR from the anti-apoptotic iASPP protein, promoting apoptosis of cancer cells. The p53 linker forms a hairpin-like structure with its two termini in close proximity. We designed a peptide derived from the disordered termini without the hairpin, designated as p53 LinkTer. The LinkTer peptide binds the disordered RT loop of iASPP with the same affinity as the parent p53 linker peptide, and inhibits the p53–iASPP interaction in vitro. The LinkTer peptide shows increased stability to proteolysis, penetrates cancer cells, causes nuclei shrinkage, and compromises the viability of cells. We conclude that a designed peptide comprising only the IDR from a peptide sequence can serve as an improved inhibitor since it binds its target protein without the need for pre-folding, paving the way for therapeutic targeting of IDRs. 相似文献