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排序方式: 共有431条查询结果,搜索用时 15 毫秒
1.
El-Hadi Ibrahim Adil Denizli Sema Bekta
mer Gen Erhan Pi
kin 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1998,720(1-2):217-224
Poly(2-hydroxyethylmethacrylate–ethyleneglycoldimethacrylate) [poly(HEMA–EGDMA)] microspheres carrying Cibacron Blue F3GA and/or thionein were prepared and used for the removal of cadmium ions Cd(II) from human plasma. The poly(HEMA–EGDMA) microspheres, in the size range of 150–200 μm in diameter, were produced by a modified suspension copolymerization of HEMA and EGDMA. The reactive triazinyl dye-ligand Cibacron Blue F3GA was then covalently incorporated into the microspheres. The maximum dye incorporation was 16.5 μmol/g. Then, thionein was bound onto the Cibacron Blue F3GA-incorporated microspheres under different conditions. The maximum amount of thionein bound was 14.3 mg/g. The maximum amounts of Cd(II) ions removed from human plasma by poly(HEMA–EGDMA)–Cibacron Blue F3GA and poly(HEMA–EGDMA)–Cibacron Blue F3GA–thionein were of 17.5 mg/g and 38.0 mg/g, respectively. Cd(II) ions could be repeatedly adsorbed and desorbed with both types of microspheres without significant loss in their adsorption capacity. 相似文献
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Summary The two high affinity calcium binding sites of the cardiac (Ca2+ + Mg2+)-ATPase have been identified with the use of Eu3+. Eu3+ competes for the two high affinity calcium sites on the enzyme. With the use of laser-pulsed fluorescent spectroscopy, the environment of the two sites appear to be heterogeneous and contain different numbers of H2O molecules coordinated to the ion. The ion appears to be occluded even further in the presence of ATP. Using non-radiative energy transfer studies, we were able to estimate the distance between the two Ca2+ sites to be between 9.4 to 10.2 A in the presence of ATP. Finally, from the assumption that the calcium site must contain four carboxylic side chains to provide the 6–8 ligands needed to coordinate calcium, and based on our recently published data, we predict the peptidic backbone of the two sites. 相似文献
4.
1. Concentrations of the neurotransmitter amines noradrenaline (NA), dopamine (DA), and 5-hydroxytryptamine (5-HT) and the acid metabolites homovanillic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) were determined in four regions of postmortem brains of demented patients with or without Alzheimer's disease (AD). 2. NA was deficient in the temporal cortex (BA 21) of AD, but not of non-AD, patients. 3. Caudate, in particular, had an impaired dopaminergic system in AD patients, with low HVA levels. 4. In all regions investigated [amygdala, caudate, putamen, temporal cortex (BA 21)] 5-HT was significantly depleted in AD patients, and 5-HIAA was also depleted in amygdala and caudate. 5. These results indicate that neurotransmitter systems other than cholinergic systems are also widely affected in AD and suggest that these deficits may also play an important role in determining the symptomatology of AD. 相似文献
5.
Molecular evidence for Triticum speltoides as a B-genome progenitor of wheat (Triticum aestivum). 总被引:3,自引:0,他引:3
In polyploid wheat, the origin of the B-genome donor has remained relatively unknown in spite of a number of investigations attempting to identify the parental species. A project was designed to isolate and clone a genome-specific DNA sequence from Triticum speltoides L. to determine if that species could be the B-genome donor. A cloning scheme involving the prescreening of 1-kb fragments followed by colony, dot blot, and Southern blot hybridization screenings was used to isolate a speltoides-specific sequence (pSp89.XI). The methods used allowed for rapid isolation of a genome-specific sequence when screened against total DNA from closely related species. Subsequent analyses showed that the sequence was barely detected in any of the other genomes of the annual Sitopsis section. The results of dot blot and Southern blot analyses established that (i) the sequence pSP89.XI, specific to T. speltoides relative to the other species of the Sitopsis section, was present in the genomes of tetraploid and hexaploid wheat, (ii) the relative abundance of pSp89.XI seemed to decrease from the diploid to the polyploid wheats, and (iii) the existence of a related, but modified B genome in polyploid wheat compared with that in modern T. speltoides was probable. Key words : genome-specific, DNA. 相似文献
6.
The bacterial succession on the skin of broiler chicken carcasses stored at 2 degrees C was traced, and the ability of representative isolates to produce off-odors was determined by using sterile leg and breast muscle sections. Off-odors were identified by olfactory and chemical means. The inability of peptone-iron agar to detect sulfide-producing strains was noted. 相似文献
7.
Wali Ahmidin Wubulikasimu Atikan yanhua Gao Omar Adil Arken Amina Yili Abulimiti Aisa Haji Akber 《International journal of peptide research and therapeutics》2020,26(4):1803-1818
International Journal of Peptide Research and Therapeutics - The purpose of this study was to separate and purify antioxidant peptides from the scorpion (Buthus martensii Karsch) protein... 相似文献
8.
Philippe Munyandamutsa Wilson Lazaro Jere Daud Kassam Austin Mtethiwa 《Ecology and evolution》2020,10(12):5694-5711
Tooth shape is used to differentiate between morphologically similar species of vertebrates, including fish. This study aimed to quantify tooth shape of three sympatric species: Haplochromis kamiranzovu, H. insidiae, and H. astatodon endemic to Lake Kivu, whose existing identification criteria are currently only qualitative. A quantitative tooth shape analysis was performed based on digitized tooth outline data with a subsequent elliptic Fourier analysis to test for differences among the three species. We looked at crown shape and size differences within H. kamiranzovu and H. insidiae at geographical, habitat, and gender levels. No comparison at habitat level was done for H. astatodon because it is found only in littoral zone. The analysis revealed significant tooth shape differences among the three species. Haplochromis astatodon had a significantly longer major cusp height and a longer and larger minor cusp than that of H. insidiae. It had also a longer major cusp height and a longer and larger minor cusp than that of H. kamiranzovu. Tooth shape differences of H. kamiranzovu and H. insidiae species were not significantly different between littoral and pelagic fish (p > .05) while differences were significant between southern and northern Lake Kivu populations (p < .05). Tooth sizes in H. kamiranzovu and H. insidiae were significantly different, both in height and width as well as in their ratios, and this was true at sex and geographic levels (p < .05), but not at habitat level (p > .05). Tooth shape was also significantly different with sharp teeth for males compared with females of southern populations versus northern ones. These shape‐ and size‐related differences between sexes suggest differences in the foraging strategies toward available food resources in the lake habitat. Further research should explain the genetic basis of the observed pattern. 相似文献
9.
Maren de Vries Adil S. Mohamed Rachel A. Prescott Ana M. Valero-Jimenez Ludovic Desvignes Rebecca OConnor Claire Steppan Joseph C. Devlin Ellie Ivanova Alberto Herrera Austin Schinlever Paige Loose Kelly Ruggles Sergei B. Koralov Annaliesa S. Anderson Joseph Binder Meike Dittmann 《Journal of virology》2021,95(10)
10.