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991.
Cartoni C Schininà ME Maras B Nonno R Vaccari G Di Baria MA Conte M Liu QG Lu M Cardone F Windl O Pocchiari M Agrimi U 《Journal of chromatography. A》2005,1081(1):122-126
Cerebral formation of the pathological isoform of the prion protein (PrP) is a crucial molecular event in prion diseases. The bank vole (Clethrionomys glareolus) is a rodent species highly susceptible to natural scrapie. The PrP gene of bank vole is polymorphic (Met/Ile) at codon 109. Here we show that homozygous 109Met/Met voles have incubation times shorter than heterozygous 109Met/Ile voles after experimental challenge with three different scrapie isolates. An HPLC-MS/MS method was optimized and applied to investigate whether in heterozygous animals both PrP allotypes are able to undergo pathological conversion. The results demonstrate that both allotypes of the prion protein participate to pathological deposition. 相似文献
992.
Martino L Virno A Pagano B Virgilio A Di Micco S Galeone A Giancola C Bifulco G Mayol L Randazzo A 《Journal of the American Chemical Society》2007,129(51):16048-16056
The complex between distamycin A and the parallel DNA quadruplex [d(TGGGGT)]4 has been studied by 1H NMR spectroscopy and isothermal titration calorimetry (ITC). To unambiguously assert that distamycin A interacts with the grooves of the quadruplex [d(TGGGGT)]4, we have analyzed the NMR titration profile of a modified quadruplex, namely [d(TGGMeGGT)]4, and we have applied the recently developed differential frequency-saturation transfer difference (DF-STD) method, for assessing the ligand-DNA binding mode. The three-dimensional structure of the 4:1 distamycin A/[d(TGGGGT)]4 complex has been determined by an in-depth NMR study followed by dynamics and mechanics calculations. All results unequivocally indicate that distamycin molecules interact with [d(TGGGGT)]4 in a 4:1 binding mode, with two antiparallel distamycin dimers that bind simultaneously two opposite grooves of the quadruplex. The affinity between distamycin A and [d(TGGGGT)]4 enhances ( approximately 10-fold) when the ratio of distamycin A to the quadruplex is increased. In this paper we report the first three-dimensional structure of a groove-binder molecule complexed to a DNA quadruplex structure. 相似文献
993.
Junfeng Wang Di Yin Zhengyou Liu Decheng Tian Yuheng Zhang 《Solid State Communications》2004,132(10):653-656
The thermoelectric power (TEP) of the quasi-one-dimensional charge-density-wave (CDW) conductors rubidium blue bronze Rb0.3MoO3 and its alloy Rb0.15K0.15MoO3 were measured in the temperature range 80-280 K. The result showed a sign change from a small positive value to a great negative value where the Peierls transition temperatures (Tp) are 183 and 180 K for Rb0.3MoO3 and Rb0.15K0.15MoO3, respectively. Above Tp, the TEP for both samples can be described with the empirical relation S=AT+B; while below Tp, the TEP fits well the relation S=AT+B/T based on the experimental data. The Fermi energies εF for Rb0.3MoO3 and Rb0.15K0.15MoO3 are estimated to be 1.55 and 0.53 eV, respectively. 相似文献
994.
S Kishino Z S Di M Sugawara K Iseki K Miyazaki S Kakinoki A Homura A Kitabatake 《Journal of chromatography. A》1992,582(1-2):246-248
A rapid and simple method for the determination of alpha 1-acid glycoprotein (AAG) in serum was developed by using an anion-exchange column for clean-up of serum and a hydroxyapatite column for high-performance liquid chromatography (HPLC). A good correlation was observed between this HPLC method and the conventional radial immunodiffusion method. The method may also be used to determine the AAG concentration in the serum of experimental animals. 相似文献
995.
Shui Cao ZHENG Huo Nan LIN Di He HU 《数学学报(英文版)》2005,21(5):1137-1148
In this paper, we investigate the Hausdorff measure for level sets of N-parameter Rd-valued stable processes, and develop a means of seeking the exact Hausdorff measure function for level sets of N-parameter Rd-valued stable processes. We show that the exact Hausdorff measure function of level sets of N-parameter Rd-valued symmetric stable processes of index α is Ф(r) = r^N-d/α (log log l/r)d/α when Nα 〉 d. In addition, we obtain a sharp lower bound for the Hausdorff measure of level sets of general (N, d, α) strictly stable processes. 相似文献
996.
The bond random mixed compound Fe(Br0.9I0.1)2 has been studied by magnetization and Mössbauer measurements. Although the zero-field cooled and field-cooled magnetization variations are not like a typical spin glass one, the Mössbauer spectrum below Néel temperature shows a hyperfine field distribution. It implies that the 10% FeI2 mixed in FeBr2 can be induced by the bond random effect which causes the sample to exhibit a spin glass-like behavior. 相似文献
997.
石墨炉原子吸收光谱法测定硬聚氯乙烯饮水管中痕量锡 总被引:1,自引:0,他引:1
本文按标准GB/T10002.1-1996方法前处理样品,硝酸钙作基体改进剂,使锡的灰化温度提高并消除干扰。方法简便,快速,准确,灵敏度和精密度高,相对标准偏差为4.55%,回收率在90%-104%范围内。 相似文献
998.
999.
1000.
T.M. Di Palma A. Latini M. Satta A. Giardini-Guidoni 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1998,4(2):225-229
A photoionization study of the Me(NH3) clusters formed in the reaction of photoablated third group metal vapor with gaseous ammonia is reported. The photoionization
spectra exhibit some features due to vibrational excitation of ionic clusters and to transitions to neutral Rydberg states
leading to autoionization. DFT quantum chemical calculations are performed on the Me(NH3). The cluster geometries are fully optimized imposing the C3v symmetry. The calculated values of the IPs are in agreement with those experimentally determined.
Received: 16 February 1998 / Revised and Accepted: 7 May 1998 相似文献