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排序方式: 共有711条查询结果,搜索用时 15 毫秒
71.
Kang Seog Lee U. Heinz E. Schnedermann 《Zeitschrift fur Physik C Particles and Fields》1990,48(3):525-541
The particle transverse momentum spectra recently measured in relativistic heavy-ion collisions at CERN and BNL are analysed within an expanding fireball model. All the particle spectra at a given beam energy can be reproduced simultaneously with a single set of intensive parameters for the initial state of the fireball. As typical freeze-out parameters in this beam energy region we find a freeze-out temperatureT f?110 MeV for most hadrons, and an average transverse expansion velocity at freeze-out of 〈v/c〉?0.4–0.45. The striking enhancement at transverse momentap T<200 MeV/c in the CERN pion data cannot be fully explained by the existence of transverse flow. 相似文献
72.
Belous K Shapkin M Sokolov A Abe K Abe K Adachi I Aihara H Anipko D Arinstein K Aulchenko V Aushev T Bakich AM Barberio E Bay A Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Browder TE Chang MC Chen A Chen KF Chen WT Cheon BG Chistov R Choi Y Choi YK Cole S Dalseno J Drutskoy A Eidelman S Epifanov D Fratina S Fujikawa M Gabyshev N Gershon T Gokhroo G Golob B Ha H Haba J Hasegawa Y Hayasaka K Hayashii H Hazumi M Heffernan D Hokuue T Hoshi Y Hou S Hou WS Iijima T Ikado K Imoto A 《Physical review letters》2007,99(1):011801
The mass of the tau lepton has been measured in the decay mode tau-->3pinutau using a pseudomass technique. The result obtained from 414 fb-1 of data collected with the Belle detector is Mtau=[1776.61+/-0.13(stat)+/-0.35(sys)] MeV/c2. The upper limit on the relative mass difference between positive and negative tau leptons is |Mtau+-Mtau-|/Mtau<2.8 x 10-4 at 90% confidence level. 相似文献
73.
Byung Hyun Kang Hye Sook Min You Jeong Lee Bomi Choi Eun Ji Kim Jonghoon Lee Jeong-Rae Kim Kwang-Hyun Cho Tae Jin Kim Kyeong Cheon Jung Seong Hoe Park 《Experimental & molecular medicine》2015,47(3):e154
Analysis of the T-cell receptor (TCR) repertoire of innate CD4+ T cells selected by major histocompatibility complex (MHC) class II-dependent thymocyte–thymocyte (T-T) interaction (T-T CD4+ T cells) is essential for predicting the characteristics of the antigens that bind to these T cells and for distinguishing T-T CD4+ T cells from other types of innate T cells. Using the TCRmini Tg mouse model, we show that the repertoire of TCRα chains in T-T CD4+ T cells was extremely diverse, in contrast to the repertoires previously described for other types of innate T cells. The TCRα chain sequences significantly overlapped between T-T CD4+ T cells and conventional CD4+ T cells in the thymus and spleen. However, the diversity of the TCRα repertoire of T-T CD4+ T cells seemed to be restricted compared with that of conventional CD4+ T cells. Interestingly, the frequency of the parental OT-II TCRα chains was significantly reduced in the process of T-T interaction. This diverse and shifted repertoire in T-T CD4+ T cells has biological relevance in terms of defense against diverse pathogens and a possible regulatory role during peripheral T-T interaction. 相似文献
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76.
A simple, rapid, and selective HPLC-diode array detector method was developed for the simultaneous determination of lidocaine hydrochloride (LD) and cetylpyridinium chloride (CPC) in two combined pharmaceutical formulations. Effective chromatographic separation was achieved on a Zorbax SB-C8 (4.6 x 250 mm, 5 microm particle size) column with gradient elution using a mobile phase composed of 0.05 M phosphoric acid and acetonitrile. The gradient elution started with 25% (v/v) acetonitrile, ramped up linearly to 85% in 5 min, and then was constant until the end of the run. The mobile phase was pumped at a flow rate of 1.2 mL/min. The multiple wavelength detector was set at 214 and 258 nm, and quantification of the analytes was based on measuring their peak areas. The retention times for LD and CPC were about 3.4 and 7.3 min, respectively. The reliability and analytical performance of the proposed HPLC procedure were statistically validated with respect to linearity, range, precision, accuracy, selectivity, robustness, LOD, and LOQ. Calibration curves were linear in the range of 5-200 and 10-400 microg/mL for LD and CPC, respectively, with correlation coefficients > 0.999. The proposed method was proven to be stability-indicating by the resolution of the two analytes from the related substance and potential impurity (2,6-dimethylaniline) as well as from forced-degradation products. The validated HPLC method was extended to the analysis of LD and CPC in two combined oral gel preparations for which the two analytes were successfully resolved from the pharmaceutical adjuvants and quantified with recoveries not less than 97.9%. 相似文献
77.
Oh BN Park S Ren J Jang YJ Kim SK Kim J 《Dalton transactions (Cambridge, England : 2003)》2011,40(24):6494-6499
In this study, an assay to quantify the presence of mercuric ions and methyl mercury by double-stranded DNA containing a poly(dT) sequence was developed using a light switch compound, Ru(phen)(2)(dppz)(2+) (1), which is known to intercalate into double-stranded DNA. Upon treatment with mercuric ions, the metal-to-ligand charge transfer (MLCT) emission derived from the intercalation of 1 was reduced due to the formation of DNA duplexes containing T-Hg(2+)-T base pairs by the dehybridization of poly(dT)-poly(dA) duplexes at room temperature. As the concentration of Hg(2+) was increased, the emission of 1 gradually decreased. This label-free method had a detection limit of 5 nM. Other metal ions, such as K(+), Ag(+), Ca(2+), Mg(2+), Zn(2+), Mn(2+), Co(2+), Ni(2+), Cu(2+), Cd(2+), Cr(3+), Fe(3+), had no significant effect on reducing emission. This emission method can differentiate matched and mismatched poly(dT) sequences based on the dehybridization rate of dsDNA and the rate decreased in the order of T(10)C·A(11)~ T(10)A·A(11) > T(10)G·A(11) > T(11)·A(11). 相似文献
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79.
Yang HM Lee HJ Park CW Yoon SR Lim S Jung BH Kim JD 《Chemical communications (Cambridge, England)》2011,47(18):5322-5324
Endosome-escapable poly(amino acid) nanoparticles composed of iron oxide nanocrystals and anticancer drugs were prepared and demonstrated high T(2) relaxivity coefficients and higher efficacy attributed to the endosomolytic ability of the conjugated histidine moiety. 相似文献
80.
Park J Lim DH Lim HJ Kwon T Choi JS Jeong S Choi IH Cheon J 《Chemical communications (Cambridge, England)》2011,47(15):4382-4384
The immune-response of macrophages is an important area of investigation since it represents the major pathway by which early-stage defense barriers are established in skin, lungs, and mucosal systems to counteract foreign objects. In this study, we have examined the size-dependent inflammatory and toxicological effects of nanostructured silver particles (nano-Ag) on macrophage immune cells. 相似文献