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931.
Park YR Choi SC Lee ST Kim KS Chae SC Chung HT 《Experimental & molecular medicine》2005,37(6):553-558
The eotaxin gene family (eotaxin, eotaxin-2 and eotaxin-3) have been implicated in the recruitment of eosinophils, basophiles and helper T (Th) 2 lymphocytes that is a central aspect of allergic disease. We previously suggested that Eo2+179T>C and Eo2 +275C>T of the eotaxin-2, and Eo3 +2497T>G of the eotaxin-3 were significantly associated with susceptibility to asthma. To determine whether the single nucleotide polymorphisms (SNPs) of eotaxin-2 and eotaxin-3 gene family are associated with the susceptibility of ulcerative colitis (UC), we analyzed the genotype of 119 patients with UC and 303 controls using single-base extension (SBE) method. We also calculated the haplotype frequencies among Eo2 +179T>C and Eo2 +275C >T of the eotaxin-2 and Eo3 +2497T>G of the eotaxin-3 in both control and UC patients. The genotype frequency of Eo2 +179T>C and Eo2 +275C>T between UC patients and controls were significantly different (P=0.006 and 0.022, respectively). The genotype and allele frequencies of EoA2497T>G in UC patients were not significantly different from those in the controls without UC patients. Our results suggest that Eo2 +179T>C and Eo2 +275C>T of eotaxin-2 might be associated with the susceptibility of UC. 相似文献
932.
Maw‐Cherng Suen Ymg‐Yann Wu Guo‐Chung Dong Jhy‐Der Chen Tai‐Chiun Keng Ju‐Chun Wang 《中国化学会会志》2002,49(3):331-334
The reaction of Zn(NO3)2·6H2O and bpp (bpp = 1,3‐Bis(4‐pyridyl)pronpane) in CH3OH afforded the complex [Zn(bpp)(NO3)2]n, 1 . The IR has been recorded and the structure has been determined. Crystal data for 1: Space group P2(1)/n, a = 11.749(1), b = 11.413(1), c = 11.942(1) Å, β = 96.06(6)°. V = 1592.5(3) Å3, Z = 4 with final residuals R1 = 0.0484 and wR2 = 0.0984. The complexes show supramolecular structure in the solid state by intermolecular hydrogen bonding interaction. 相似文献
933.
934.
Dong M. Chung Balram S. Rajput Albert Tortrat 《Probability Theory and Related Fields》1982,60(2):209-218
Summary In this paper we discuss three types of results: Firstly, we present two Lévy-Hinin type representations of Poisson type infinitely divisible (i.d.) laws on certain topological vector (TV) spaces; one of these complements a known representation due to Dettweiler. Secondly, we define and characterize r-semistable laws on locally convex TV spaces and also obtain good representation of their characteristic functions. Finally, we discuss the existence and the continuity of the semigroup {
tt>0} of i.d. laws on locally convex TV spaces. These complement similar known results of Siebert.The research of this author is partially supported by the Office of Naval Research under contract No. N0014-78-C-0468 相似文献
935.
Kai Lai Chung 《Journal of Theoretical Probability》1993,6(3):417-426
Doeblin regarded his paper(2) as his hardest work. The big limit is that ofP(n)(x, E) asn tends to infinity, in a measurable non-topologized space. An exposition of part one of this paper was published in Ref. 1. This is the exposition of part two, which contains some reparation as well as clarification.Doeblin's great contributions to probability theory were remembered at a conference 50 Years after Doeblin: Developments in the Theory of Markov Chains, Markov Processes and Sums of Random Variables held at Blaubeuren. Germany November 2–7, 1991. Professor Chung contributed this article to further celebrate this occasion. The editor thanks him. 相似文献
936.
937.
938.
An electrorefractive index-controllable guide/antiguide optical intensity modulator has been created and characterized. The operating mechanism, beam propagation method simulation, device design and fabrication, and calculated and experimental results of this guide/antiguide modulator are given. The operational principle of the modulator is based on the field-induced waveguide (FIG) concept; that is, electric-field-induced refractive index changes cause the waveguide to be turned on and off electrically. The modulator is formed with a central narrow FIG electrode sandwiched between two antiguide electrodes. The electrooptic effects, along with carrier effects, have been exploited to adjust the refractive index under the guide and adjacent antiguide electrodes by changing reverse biases applied to them. The modulation is determined mainly by changing the lateral refractive index profiles. In the on state, a waveguide is formed under the central electrode, and the input light propagates along this waveguide. To realize the best off state, an antiguide situation is created that causes the light to diffract out of the central guide rapidly. An on/off ratio larger than 23 dB, a propagation loss 1 dB, and a record optical bandwidth from 1.0 to 1.55 m have been obtained for this modulator. 相似文献
939.
This work estimated the porosities of activated sludge flocs, cationic polyelectrolyte flocculated, based on free-settling tests, buoyant weight measurements, and confocal laser scanning microscope (CLSM) tests. The extent of advective flow was estimated based on bubble-tracking test. The former two measurements suggested a close-to-unity porosity, that is, an extremely void floc interior. Meanwhile, the latter two tests recommended a dense floc interior with a porosity less than 64%. A discrepancy exists between the porosities estimated by various tests. A floc model was proposed based on the understanding that a vast amount of bound water in the floc was regarded as void in buoyant weight measurement, but was impermeable for advective flow. The distribution rather than the mean value of the porosity controls the advective flow. There existed no simple correlation between the porosities measured by different tests. 相似文献
940.
Reaction monitoring of succinylation of collagen with matrix-assisted laser desorption/ionization mass spectrometry 总被引:1,自引:0,他引:1
Kim SH Lee JH Yun SY Yoo JS Jun CH Chung KY Suh H 《Rapid communications in mass spectrometry : RCM》2000,14(22):2125-2128
Succinylated collagen was synthesized by the reaction of collagen with succinic anhydride under basic conditions for one hour. Using the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) technique, the reaction products were directly identified without multi-step separation processes. MALDI-MS monitored the reaction more accurately than the conventional method of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). From the change in molecular mass during the reaction, it is observed that about 28 succinyl groups are attached to the collagen strand. 相似文献