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排序方式: 共有492条查询结果,搜索用时 15 毫秒
1.
In this paper the synthetic methods of three covalently linked porphyrin-phthalocyanine heteropentamers, containing four units of porphyrin linked to a central phthalocyanine (Mpor-LPc; M = 2H, Fe, L = Zn, Fe), are described. The synthetic strategy is on the basis of nucleophilic substitution reactions between [1,8,15,22-tetra nitro phthalocyanines] and [5-(4-hydroxy phenyl)-10,15,20-triphenyl porphyrins] as the phenolic alcohols. Porphyrins are linked with oxygen as spacer through meso position of phenyl group to phthalocyanines. These macromolecules were characterized by 1H NMR, UV-Vis, IR, fluorescence and mass spectroscopy. The electronic absorption spectrums of the hetero-dyad systems changed significantly upon coupling and showed a great red shift in the phthalocyanine Q-bands. These changes confirm the electron-donating effects of the porphyrin units and the extension of conjugated п-systems. The emission spectra of the products supports intramolecular energy and charge transfer between the sub-units. 相似文献
2.
The kinetics of lipid peroxide decomposition catalysed by microsomal enzymes and inhibited by SKF-525 A, hexobarbital, phenobarbital and aniline were investigated. The results indicate that the in vitro interaction of hexobarbital and SKF-525 A (type I binding compounds) with microsomal cytochrome p-450 inhibits the peroxidase activity while the in vitro interaction of aniline (type II binding compound) only slightly affect the peroxidase activity. It is suggested that LAHPO and type I binding compounds are competing for the hydrophobic binding site on cytochrome p-450, while type II binding compounds such as aniline negate electron transfer non-competitively by combining with the heme. 相似文献
3.
Tabaei Samira Motallebnezhad Morteza Tabaee Seyedeh Samaneh 《Biochemical genetics》2021,59(4):813-836
Biochemical Genetics - Several studies have noted that vitamin D receptor (VDR) gene polymorphisms are involved in the susceptibility to Coronary artery disease (CAD). Nonetheless, the results have... 相似文献
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Donato Spoltore Wibren D. Oosterbaan Samira Khelifi John N. Clifford Aurelien Viterisi Emilio Palomares Marc Burgelman Laurence Lutsen Dirk Vanderzande Jean Manca 《Liver Transplantation》2013,3(4):466-471
The non‐geminate recombination of charge carriers in polymer‐fullerene solar cells has been modeled in the last few years with a trap‐assisted recombination model, which states that the apparent recombination order depends on the concentration of trapped charges tailing into the band gap. Higher concentrations of trapped charges lead to higher apparent recombination orders. In this work, the mass fraction f of highly crystalline nanofibrillar P3HT to the total P3HT content in P3HT:PCBM solar cells is consistently varied, controlling the temperature of a nanofibers‐P3HT casting dispersion. A systematic study of the apparent recombination order, measured with a transient photovoltage technique, as a function of f is presented. A correlation is shown between the apparent recombination order, the P3HT crystallinity, and the trap concentration in the band gap measured with an admittance spectroscopy technique. 相似文献
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Alinaghi Mirmoayedi Danial Kahrizi Samira Pani Kheirollah Yari 《Molecular biology reports》2013,40(1):639-643
Antlions are insects which feed on ants, insect which dig a pit and lies in wait for ants and other insects. Twelve species of Myrmeleontidae family as antlions and many specimens were identified in different locations in Fars province in Iran. To unveil the genetic similarity between these species, their DNA was extracted by modified CTAB method and with the use of seventeen 10-nucleotides primers of random amplified polymorphic DNA (RAPD); the genetic analysis of them was investigated. After PCR, agarose 1.5?% was used for electrophoresis. The obtained electrophoresis bands had base pairs range between 150 and 1,000?bp. The maximum of polymorphic bands belonged to OPH5, N13, and the minimum of polymorphic bands belonged to OPA7 primers. Different genetic similarity indices were found between eight species of antlions. Possibility of use of RAPD marker together with morphological studies for classification and identification of antlions is discussed. 相似文献
8.
Amanda V. Steckert Samira S. Valvassori Roger B. Varela Francielle Mina Wilson R. Resende Daniela V. Bavaresco Felipe Ornell Felipe Dal-Pizzol João Quevedo 《Neurochemistry international》2013
Several evidences have demonstrated that oxidative stress has a central role in bipolar disorder (BD). Recently, studies have been suggested histone deacetylases (HDAC) as a possible target for new medications in treatment of mood disorders. In this study, we investigated the effects of sodium butyrate (SB, a histone deacetilase inhibitor) on oxidative stress in rats submitted to an animal model of mania induced by d-amphetamine (d-AMPH). Wistar rats were first given d-AMPH or saline (Sal) for 14 days, and then, between days 8 and 14, rats were treated with SB or Sal. Locomotor activity and risk-taking behavior were assessed by open-field test and oxidative stress was measured in prefrontal cortex, amygdala, hippocampus and striatum. The results showed that SB reversed and prevented d-AMPH-induced behavioral effects. The d-AMPH administration induced oxidative damage in all brain structures analyzed. Depending on the cerebral area and technique, SB was able to reverse this impairment. The present study reinforces the need for more studies of HDAC inhibitors as possible target for new medications in treatment for BD. 相似文献
9.
Elisa Tran Annabelle Chow Takeshi Goda Amy Wong Kim Blakely Michelle Rocha Samira Taeb Van C. Hoang Stanley K. Liu Urban Emmenegger 《Biochemical and biophysical research communications》2013
ATG4B belongs to the autophagin family of cysteine proteases required for autophagy, an emerging target of cancer therapy. Developing pharmacological ATG4B inhibitors is a very active area of research. However, detailed studies on the role of ATG4B during anticancer therapy are lacking. By analyzing PC-3 and C4-2 prostate cancer cells overexpressing dominant negative ATG4BC74Ain vitro and in vivo, we show that the effects of ATG4BC74A are cell type, treatment, and context-dependent. ATG4BC74A expression can either amplify the effects of cytotoxic therapies or contribute to treatment resistance. Thus, the successful clinical application of ATG4B inhibitors will depend on finding predictive markers of response. 相似文献
10.
Renato T. Souza Jose G. Cecatti Renato Passini Jr. Ricardo P. Tedesco Giuliane J. Lajos Marcelo L. Nomura Patricia M. Rehder Tabata Z. Dias Samira M. Haddad Rodolfo C. Pacagnella Maria L. Costa Brazilian Multicenter Study on Preterm Birth study group 《PloS one》2016,11(2)