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991.
992.
为了解中山大学附属第三医院抗精神病药的用药趋势及用药现况,采用WHO推荐使用的以DDD数(DDDs)为指标的药物利用研究方法,对该院2002-2004年抗精神病药的消耗情况进行统计、分析.结果表明,该院抗精神病药用药金额及用药人次逐年增多,其中经典抗精神病药呈下降趋势,非经典抗精神病药呈上升趋势.提示疗效好、副作用小的非经典抗精神病药将逐渐取代传统经典抗精神病药. 相似文献
993.
Zoë C. Adams Erika J. Olson Tania L. Lopez-Silva Zhengwen Lian Audrey Y. Kim Matthew Holcomb Jrg Zimmermann Ramkrishna Adhikary Philip E. Dawson 《Chemical science》2022,13(34):10020
The characterization of self-assembling molecules presents significant experimental challenges, especially when associated with phase separation or precipitation. Transparent window infrared (IR) spectroscopy leverages site-specific probes that absorb in the “transparent window” region of the biomolecular IR spectrum. Carbon–deuterium (C–D) bonds are especially compelling transparent window probes since they are non-perturbative, can be readily introduced site selectively into peptides and proteins, and their stretch frequencies are sensitive to changes in the local molecular environment. Importantly, IR spectroscopy can be applied to a wide range of molecular samples regardless of solubility or physical state, making it an ideal technique for addressing the solubility challenges presented by self-assembling molecules. Here, we present the first continuous observation of transparent window probes following stopped-flow initiation. To demonstrate utility in a self-assembling system, we selected the MAX1 peptide hydrogel, a biocompatible material that has significant promise for use in drug delivery and medical applications. C–D labeled valine was synthetically introduced into five distinct positions of the twenty-residue MAX1 β-hairpin peptide. Consistent with current structural models, steady-state IR absorption frequencies and linewidths of C–D bonds at all labeled positions indicate that these side chains occupy a hydrophobic region of the hydrogel and that the motion of side chains located in the middle of the hairpin is more restricted than those located on the hairpin ends. Following a rapid change in ionic strength to initiate self-assembly, the peptide absorption spectra were monitored as function of time, allowing determination of site-specific time constants. We find that within the experimental resolution, MAX1 self-assembly occurs as a cooperative process. These studies suggest that stopped-flow transparent window FTIR can be extended to other time-resolved applications, such as protein folding and enzyme kinetics.To facilitate the characterization of phase-transitioning molecules, site-specific non-perturbative infrared probes are leveraged for continuous observation of the self-assembly of fibrils in a peptide hydrogel following stopped-flow initiation. 相似文献
994.
Acid catalysis,one of the most important industrial processes,suffers from the toxicity,corrosion and recyclability problems of conventional homogeneous acid ca... 相似文献
995.
Synthesis, Crystal Structure and Photoluminescent Property of a 3D Hydrogen-bonded Supramolecular Compound with Large Channels 总被引:1,自引:1,他引:0
YUE Cheng-Yang JIANG Fei-Long YUAN Da-Qiang CHEN Lian WU Ming-Yan HONG Mao-Chun 《结构化学》2008,27(4):467-470
The title compound, [Pd(2,2′-bipy)2](Haadip)2·4H2O, was synthesized via the hydrothermal reaction of PdCl2 with 5-aminodiacetic isophthalic acid (H4adip) in an acetic acid water solution. It was characterized by elemental analysis and infrared spectrum. Crystal data for C44H44N6O20Pd: monoclinic, space group P21/n, a = 11.0674(2), b = 9.9716(2), c= 20.5770(3)A, β = 92.7300(3)°, V = 2268.29(7)A^3, Z = 2, Mr = 1083.25, Dc = 1.586 g/cm^3, F(000) = 1112,μ = 0.499 mm^-1, 2(MoKa) = 0.71073 A, T = 293(2) K, 2θmax = 51.38°, GOOF = 1.067, R = 0.0268 and wR = 0.0710 for 3770 reflections with 1 〉 2σ(I). X-ray diffraction studies reveal that the title compound has an interesting 3D microporous architecture via hydrogen bonds with the cations located inside the channel. 相似文献
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毛细管电泳柱后衍生激光诱导荧光测定动物组织中卡那霉素类抗生素 总被引:5,自引:1,他引:4
采用毛细管电泳柱后衍生激光诱导荧光测定3种卡那霉素类抗生素。研究了在反向电渗流条件下HAc-NaAc缓冲液酸度和浓度对卡那霉素类抗生素分离的影响,研究了Na2B4O7缓冲体系和柱后衍生试剂萘二醛/2-巯基乙醇浓度对检测信号的影响。采用50 mmol/L HAc-NaAc(pH5.0) 0.5 mmol/L CTMAB溶液为分离缓冲液,样品在-15 kV下分离,与柱后衍生试剂1.0 mmol/L NDA 8.0 mmol/L 2-ME 35 mmol/LNa2B4O7(pH10.0)的30%(V/V)甲醇溶液反应,激发诱导荧光检测卡那霉素类抗生素检出限为3.6×10-5~5.2×10-5g/L;本方法用于动物组织中卡那霉素类抗生素残留检测,相对标准偏差小于7.2%;回收率为90.2%~95.3%(n=4)。 相似文献
999.
建立了基于自制全密闭进样系统的气相色谱-质谱测定全氟异丁腈(C4F7N)商品气中杂质的方法。待测气体在自制的密封系统内稀释并混合均匀,使用在线自动六通阀进样,采用Agilent GS-GASPRO色谱柱(30 m×0.32 mm×5μm)分离,测定了国内某公司(DC公司)和国外某公司(AC公司)的全氟异丁腈绝缘气体的杂质成分。结果表明,全氟异丁腈商品气中含有微量的N2、O2、C3HF7和痕量的C3F6,其中AC公司的C4F7N商品气体中的杂质总含量为0.13%, C4F7N纯度为99.87%; DC公司的C4F7N商品气体中的杂质总含量为0.83%, C4F7N纯度为99.17%,两家公司的C4F7 相似文献
1000.