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41.
A higher percentage of di-N-2 propylpentyl phthalate isolated from the urine of the normals and a lower quantity in the patients suffering from Eales' disease accompanied with the occurrence in patients of another compound which is also most likely a phthalate ester has been correlated with the Eales' disease. 相似文献
42.
N. Ahmad S. A. Ahmad A. A. Khan A. Shoeb 《Cellular and molecular life sciences : CMLS》1979,35(6):736-737
Summary A higher percentage of di-N-2 propylpentyl phthalate isolated from the urine of the normals and a lower quantity in the patients suffering from Eales' disease accompanied with the occurrence in patients of another compound which is also most likely a phthalate ester has been correlated with the Eales' disease.Acknowledgement. This work was supported by grants from the Indian Council of Medical Research, New Delhi, India. 相似文献
43.
Taher Yousefi Reza Davarkhah Ahmad Nozad Golikan Mohammad HosseinMashhadizadeh Ahmad Abhari 《自然科学进展(英文版)》2013,23(1):51-54
Fe2O3 nano-particles have been synthesized by simple cathodic electrodeposition from the low-temperature nitrate bath.The morphology and crystal structure of the obtained oxide powder were analyzed by means of scanning and transmission microscopy(SEM and TEM),X-ray diffraction(XRD) and Fourier transform infrared(FTIR) spectroscopy.Thermal behavior and phase transformation during the heat treatment of as-deposited sample were investigated by differential scanning calorimetry(DSC) and thermogramimetric analysis(TGA).The results showed that the deposited Fe2O3 was composed of the nanoparticles with grain size of approximately 10-60 nm.A serious problem during cathodic electrodeposition of iron oxide was splashing of deposit into electrolyte due to its low adhesion.This problem was tackled by reducing the bath temperature and dielectric constant of solvent. 相似文献
44.
用两比特海森堡XY模型实现量子稠密编码 总被引:1,自引:1,他引:0
文章主要研究在有限温度下,外加磁场和DM相互作用对两比特海森堡XY模型中实现量子稠密编码的影响。通过稠密编码的信道容量表达式分析了每个参数对稠密编码的影响并且发现平均耦合常数J-,DM相互作用和各向异性参数J+对稠密编码起积极作用。均匀磁场B和非均匀磁场b对稠密编码起消极作用。 相似文献
45.
The effects of Ce on the secondary dendrite arm spacing (SDAS) and mechanical behavior of Al-Si-Cu-Mg alloys were investigated. The reduction of SDAS at different Ce concentrations was evaluated in a directional solidification experiment via computer-aided cooling curve thermal analysis (CA CCTA). -The results showed that 0.1wt%-1.0wt% Ce addition resulted in a rapid solidification time, △TS, and low solidification temperature, △TS, whereas 0.1wt% Ce resulted in a fast solidification time, △ta-Al, of the α-Al phase. Furthermore, Ce addition refined the SDAS, which was reduced to approximately 36%. The mechanical properties of the alloys with and without Ce were investigated using tensile and hardness tests. The quality index (Q) and ultimate tensile strength of (UTS) Al-Si-Cu-Mg alloys significantly improved with the addition of 0.1wt% Ce. Moreover, the base alloy hardness was improved with increasing Ce concentration. 相似文献
46.
Melatonin receptors limit dopamine reuptake by regulating dopamine transporter cell-surface exposure
Abla Benleulmi-Chaachoua Alan Hegron Marine Le Boulch Angeliki Karamitri Marta Wierzbicka Victoria Wong Igor Stagljar Philippe Delagrange Raise Ahmad Ralf Jockers 《Cellular and molecular life sciences : CMLS》2018,75(23):4357-4370
Melatonin, a neuro-hormone released by the pineal gland, has multiple effects in the central nervous system including the regulation of dopamine (DA) levels, but how melatonin accomplishes this task is not clear. Here, we show that melatonin MT1 and MT2 receptors co-immunoprecipitate with the DA transporter (DAT) in mouse striatal synaptosomes. Increased DA re-uptake and decreased amphetamine-induced locomotor activity were observed in the striatum of mice with targeted deletion of MT1 or MT2 receptors. In vitro experiments confirmed the interactions and recapitulated the inhibitory effect of melatonin receptors on DA re-uptake. Melatonin receptors retained DAT in the endoplasmic reticulum in its immature non-glycosylated form. In conclusion, we reveal one of the first molecular complexes between G protein-coupled receptors (MT1 and MT2) and transporters (DAT) in which melatonin receptors regulate the availability of DAT at the plasma membrane, thus limiting the striatal DA re-uptake capacity in mice. 相似文献
47.
Brice Hoffmann Ahmad Elbahnsi Pierre Lehn Jean-Luc Décout Fabio Pietrucci Jean-Paul Mornon Isabelle Callebaut 《Cellular and molecular life sciences : CMLS》2018,75(20):3829-3855
Cryo-electron microscopy (cryo-EM) has recently provided invaluable experimental data about the full-length cystic fibrosis transmembrane conductance regulator (CFTR) 3D structure. However, this experimental information deals with inactive states of the channel, either in an apo, quiescent conformation, in which nucleotide-binding domains (NBDs) are widely separated or in an ATP-bound, yet closed conformation. Here, we show that 3D structure models of the open and closed forms of the channel, now further supported by metadynamics simulations and by comparison with the cryo-EM data, could be used to gain some insights into critical features of the conformational transition toward active CFTR forms. These critical elements lie within membrane-spanning domains but also within NBD1 and the N-terminal extension, in which conformational plasticity is predicted to occur to help the interaction with filamin, one of the CFTR cellular partners. 相似文献
48.
Muhammad Waqas Guftaar Ahmad Sardar Sidhu Tayyaba Jabeen Muhammad Afaq Ahmad Muhammad Awais Javed 《清华大学学报》2018,(1)
In this paper,we consider the power optimization problem in Orthogonal Frequency Division Multiplexing(OFDM)-based relay-enhanced device-to-device(D2D) communication.In a single cell transmission scenario,dualhop communication is assumed in which each D2D user re-uses the spectrum of just one Cellular User(CU).In this work,we formulate a joint optimization scheme under a Decode-and-Forward(DF) relaying protocol to maximize the sum throughput of D2D and cellular networks via power allocation over different sub-carriers.The problem is thus transformed into a standard convex optimization,subject to individual power constraints at different transmitting nodes.We exploit the duality theory to decompose the problem into several sub-problems and use Karush–Kuhn–Tucker(KKT) conditions to solve each sub-problem.We provide simulation results to validate the performance of our proposed scheme. 相似文献
49.
Preparation,characterization, and antibacterial activity of γ-irradiated silver nanoparticles in aqueous gelatin
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Majid Darroudi Mansor B. Ahmad Mohammad Hakimi Reza Zamiri Ali Khorsand Zak Hasan Ali Hosseini Mohsen Zargar 《矿物冶金与材料学报》2013,20(4):403-409
Colloidal silver nanoparticles (Ag-NPs) were obtained through γ-irradiation of aqueous solutions containing AgNO3 and gelatin as a silver source and stabilizer, respectively. The absorbed dose of γ-irradiation influences the particle diameter of the Ag-NPs, as evidenced from surface plasmon resonance (SPR) and transmission electron microscopy (TEM) images. When the γ-irradiation dose was increased (from 2 to 50 kGy), the mean particle size was decreased continuously as a result of γ-induced Ag-NPs fragmentation. The antibacterial properties of the Ag-NPs were tested against Methicillinresistant Staphylococcus aureus (MRSA) (Gram-positive) and Pseudomonas aeruginosa (P.a) (Gram-negative) bacteria. This approach reveals that the γ-irradiation-mediated method is a promising simple route for synthesizing highly stable Ag-NPs in aqueous solutions with good antibacterial properties for different applications. 相似文献
50.