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排序方式: 共有215条查询结果,搜索用时 31 毫秒
121.
Rhizomelic chondrodysplasia punctata is a member of genetic peroxisomal disorders. Delayed myelination, which is probably related to the inadequacy of plasmalogens biosynthesis, is an important feature of this disorder. Direct assessment of neuropathologic aspects of RCDP syndrome such as neuronal degeneration and delayed myelination is possible with MR spectroscopy.In this report, MR spectroscopy findings (decreased Cho/Cr and increased Ins-Gly/Cr ratios and increased levels of mobile lipids) of a rhizomelic chondrodysplasia punctata case supporting delayed myelination are presented. This is the second report of MR spectroscopy examination of the specific brain metabolic changes associated with rhizomelic chondrodysplasia punctata. 相似文献
122.
Alkan A Sarac K Kutlu R Yakinci C Sigirci A Aslan M Ozcan H Yologlu S 《Magnetic resonance imaging》2003,21(9):1049-1053
To determine whether differences exist between neurofibromatosis type 1 (NF1) patients with or without focal lesions and healthy normal volunteers in the metabolite ratios of normal appearing white matter, 27 patients with NF1 (with parenchymal lesion, MR positive, n: 17; without parenchymal lesions, MR negative, n: 10) and 20 healthy volunteers underwent MRI and short TE (31 ms) proton MR spectroscopy (MRS). In 17 patients with parenchymal lesions, 61 focal lesions were detected by MRI. MRS was performed from normal appearing frontal and posterior parietal white matter (FWM and PWM) in NF1 and from control groups. NAA/Cr, Cho/Cr and MI/Cr ratios were calculated. Significant increase in Cho/Cr and MI/Cr ratios were found in FWM and PWM in MR negative and positive groups when compared to control group. NAA/Cr ratio in MR positive group was significantly decreased in FWM compared to control group. There were no significant differences between FWM and PWM in all metabolite ratios of MR negative group. MI/Cr ratio in MR positive group was significantly elevated in PWM compared to FWM. Metabolite changes detected by MRS could indicate demyelination and gliosis in normal appearing white matter in all NF1 patients, and additionally neuroaxonal damage in the FWM of NF1 patients with focal lesions. For that reason, in the clinical evaluation and follow-up of these patients MRS features of normal appearing white matter should be considered in addition to focal lesions. 相似文献
123.
İsmail Aslan 《Communications in Nonlinear Science & Numerical Simulation》2012,17(12):5286-5287
We show that two of the nonlinear lattice equations studied by Ayhan & Bekir [Commun Nonlinear Sci Numer Simulat 17 (2012) 3490–3498] have already been investigated by Aslan [Commun Nonlinear Sci Numer Simulat 15 (2010) 1967–1973] using an improved version of the same method. The solutions obtained by the latter one include the solutions obtained by the former one. 相似文献
124.
Sıdır Yadigar Gülseven Aslan Cebrail Berber Halil Sıdır İsa 《Structural chemistry》2019,30(3):835-851
Structural Chemistry - The electronic structure and electronic transitions of four new mono Schiff base derivatives are interpreted by using absorption and fluorescence spectra including 28... 相似文献
125.
High‐temperature high‐performance liquid chromatography on a porous graphitized carbon column coupled to an Orbitrap mass spectrometer with atmospheric pressure photoionization for screening exogenous anabolic steroids in human urine
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126.
Recently, many important nonlinear partial differential equations arising in the applied physical and mathematical sciences have been tackled by a popular approach, the so-called Exp-function method. In this paper, we present some shortcomings of this method by analyzing the results of recently published papers. We also discuss the possible improvement of the effectiveness of the method. 相似文献
127.
smail Aslan 《Applied mathematics and computation》2009,215(2):857-863
In this paper, we demonstrate the effectiveness of the so-called (G′/G)-expansion method by examining some nonlinear evolution equations with physical interest. Our work is motivated by the fact that the (G′/G)-expansion method provides not only more general forms of solutions but also periodic and solitary waves. If we set the parameters in the obtained wider set of solutions as special values, then some previously known solutions can be recovered. The method appears to be easier and faster by means of a symbolic computation system. 相似文献
128.
In this rapid communication we describe a new approach to protein detection with chemiluminescence. By combining common practices in protein detection with chemiluminescence, microwave technology, and metal-enhanced chemiluminescence, we show that we can use low power microwaves to substantially increase enzymatic chemiluminescent reaction rates on metal substrates. As a result, we have found that we can in essence trigger chemiluminescence with low power microwave (Mw) pulses and ultimately, perform on-demand protein detection assays. Using microwave triggered metal-enhanced chemiluminescence (MT-MEC), we not only improve the sensitivity of immunoassays with enhanced signal-to-noise ratios, but we also show that we can accurately quantify protein concentrations by integrating the photon flux for discrete time intervals. 相似文献
129.
?rfan Aslan Gökhan Budak Engin T?ra?ogˇlu 《Journal of Quantitative Spectroscopy & Radiative Transfer》2006,97(1):75-80
The metal content of Colorado potato beetles elytra in Turkey was determined using the energy dispersive X-ray fluorescence method. A radioisotope excited X-ray fluorescence analysis using the method of standard addition is applied for the elemental analysis of Colorado potato beetles elytra. An annular 241Am radioactive source and an annular 55Fe radioactive source were used for excitation of characteristic K X-rays. An Si(Li) detector which has a full-width at half-maximum for photons was used for intensity measurements. The procedure of sample preparation and the results of analysis were presented. 相似文献
130.
Turgut Ozis Imail Aslan 《理论物理通讯》2009,51(4):577-580
With the aid of symbolic computation system Mathematica, several explicit solutions for Fisher's equation and CKdV equation are constructed by utilizing an auxiliary equation method, the so called G′/G-expansion method, where the new and more general forms of solutions are also constructed. When the parameters are taken as special values, the previously known solutions are recovered. 相似文献