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871.
Background
Major depression is a serious mood disorder affecting millions of adults and children worldwide. While the etiopathology of depression remains obscure, antidepressant medications increase synaptic levels of monoamine neurotransmitters in brain regions associated with the disease. Monoamine transmitters activate multiple signaling cascades some of which have been investigated as potential mediators of depression or antidepressant drug action. However, the diacylglycerol arm of phosphoinositide signaling cascades has not been systematically investigated, even though downstream targets of this cascade have been implicated in depression. With the ultimate goal of uncovering the primary postsynaptic actions that may initiate cellular antidepressive signaling, we have examined the antidepressant-induced production of CDP-diacylglycerol which is both a product of diacylglycerol phosphorylation and a precursor for the synthesis of physiologically critical glycerophospholipids such as the phosphatidylinositides. For this, drug effects on [3H]cytidine-labeled CDP-diacylglycerol and [3H]inositol-labeled phosphatidylinositides were measured in response to the tricyclics desipramine and imipramine, the selective serotonin reuptake inhibitors fluoxetine and paroxetine, the atypical antidepressants maprotiline and nomifensine, and several monoamine oxidase inhibitors. 相似文献872.
Chunyan Cao Weiping Qin Jisen Zhang Guofeng Wang Peifen Zhu Longzhen Jin 《Optics Communications》2008,281(6):1716-1719
Tm3+/Er3+/Yb3+ tri-doped CaF2 phosphors were synthesized using a hydrothermal method. The phosphors were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and up-conversion (UC) emission spectra. After annealing, the phosphors emitted white light under a 980 nm continuous wave diode laser (CW LD 2 W) excitation. As the excitation power density changed in the range of 20-260 W/cm2, the chromaticity coordinates of the UC light of the phosphor Ca0.885Tm0.005Er0.01Yb0.1F2 fell well in the white region of the 1931 CIE diagram. For the proportion of red, green and blue (RGB) in white light is strict, key factors for achieving UC white light, such as host materials, rare earth ions doping concentrations, annealing temperatures, as well as the excitation power densities, were investigated and discussed. 相似文献
873.
Using the quantum hydrodynamic (QHD) equations with magnetic field on the Wigner-Maxwell system, the general dielectric tensor and dispersion equation for quantum plasmas were derived. Dispersion relations of one-, two-stream and beam-plasma instabilities in uniform quantum magnetized plasmas are investigated through the new dielectric tensor. The magnetic field which is parallel to the fluid velocity does not work on stream instabilities. The quantum and thermal effects have remarkable impact on two-stream instability. The critical wave number for beam-plasma instability with quantum effects correction is given too. 相似文献
874.
Lili Tian Feng Zhang Juntao Liu Xinguang Wang Yongzhou Ti 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(1):51-56
A prompt gamma neutron activation analysis borehole logging method for copper, nickel and iron grade estimation is proposed. The performance of the method was simulated by MCNP5 code. Based on the theory of neutron–gamma distribution on the borehole condition, the BGO scintillator and 3He neutron tube are adopted to record gamma ray spectrum and thermal neutron simultaneously, and least square method is used for the characteristic gamma ray counts calculation in the high energy range. The results of detection limit of metal grade in borehole condition indicate that the effectiveness of this logging method. 相似文献
875.
Anthony D. Appelhans John E. Olson David A. Dahl Michal B. Ward Troy A. Robinson James E. Delmore 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(2):207-209
A new isotope separator has been designed, constructed, and put into routine operation for separation of 133Xe providing a major advancement and significant cost reduction in preparation of this radioactive isotope. The design features and advantages are discussed that expedite high purity separation of relatively small quantities of this isotope. These advantages could be easily used to expedite separation of other shorter-lived radioactive isotopes. 相似文献
876.
A. A. Naqvi F. Z. Khiari Fatai A. Liadi Khateeb-ur-Rehman M. Raashid A. A. Isab 《Journal of Radioanalytical and Nuclear Chemistry》2018,315(3):475-480
Prompt gamma ray analysis of soil samples contaminated with petroleum hydrocarbons(PHC) like benzene was carried out using 14 MeV neutron beams. Intensities of silicon, carbon, oxygen, and hydrogen gamma rays were measured for soil samples containing 2.20–10.4 wt% benzene. With increasing benzene concentration, the intensity of the C gamma rays increased while those of Si, H, and O gamma rays decreased. The reduction in Si, H, and O gamma ray intensities may be due to increasing neutron moderation effect in benzene-contaminated soil samples. The experimental intensities of gamma rays are in good agreement with the calculated intensities.The neutron moderation effects in benzene contaminated soil samples are about 26% weaker than those reported for soil samples containing moisture. From the slopes of silicon gamma ray intensity as a function of benzene concentration as well as moisture concentration, a simple scheme has been suggested to correct for the loss in carbon counts caused by neutron moderation from PHC and moisture in the soil samples. 相似文献
877.
Richard M. Lindstrom 《Journal of Radioanalytical and Nuclear Chemistry》2018,318(3):1465-1471
For more than 50 years, nuclear methods have been applied to chemical analysis at the National Institute of Standards and Technology. Radiochemical, instrumental, and prompt-gamma activation analysis are used, as well as neutron depth profiling and other techniques. The history of this group in methods development and the certification of Standard Reference Materials, among other applications, is reviewed. 相似文献
878.
879.
The sensitive and selective detection of nucleic acids is important for basic research and many applied fields. Herein, a novel green DEAB-TO-1 was designed and synthesized. DEAB-TO-1 shows significant fluorescence enhancement (800-fold) when bound to ctDNA and a distinct selectivity for dsDNA over RNA (5.9 times). Moreover, the limit of detection is 0.57 ng/mL. It is live-cell-permeant DNA intecalator, indicating a promising candidate for nucleus-specific imaging and a good counter-stain compatibility with other dyes. 相似文献
880.
正The University of Science and Technology of China(USTC)is a prominent institution with an excellent reputation for education and innovation that resonates across the world.The university holds a special place in history.It was established by the Chinese Academy of Sciences(CAS)in1958 to meet China’s science and technology needs and increase the country’s international competitiveness.Throughout its history we have focused on frontier areas of science and technology and educated top leaders in science and technology for China and the world. 相似文献