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991.
Jung HW La SJ Kim JY Heo SK Kim JY Wang S Kim KK Lee KM Cho HR Lee HW Kwon B Kim BS Kwon BS 《Experimental & molecular medicine》2003,35(6):501-508
Herpes virus entry mediator (HVEM) is a newly discovered member of the tumor necrosis factor receptor (TNFR) superfamily that has a role in herpes simplex virus entry, in T cell activation and in tumor immunity. We generated mAb against HVEM and detected soluble HVEM (SHVEM) in the sera of patients with various autoimmune diseases. HVEM was constitutively expressed on CD4(+) and CD8(+) T cells, CD19(+) B cells, CD14(+) monocytes, neutrophils and dendritic cells. In three-way MLR, mAb 122 and 139 were agonists and mAb 108 had blocking activity. An ELISA was developed to detect sHVEM in patient sera. sHVEM levels were elevated in sera of patients with allergic asthma, atopic dermatitis and rheumatoid arthritis. The mAbs discussed here may be useful for studies of the role of HVEM in immune responses. Detection of soluble HVEM might have diagnostic and prognostic value in certain immunological disorders. 相似文献
992.
A new triterpenoid, fornicatin C (= (3β)‐3‐hydroxy‐18(13 → 12β)‐abeo‐lanosta‐13(17),24‐dien‐18‐oic acid; 1 ), was isolated from the fruiting bodies of Ganoderma fornicatum, together with the known compounds fornicatin A ( 2 ) and fornicatin B ( 3 ), among other constituents. The structure of 1 was elucidated by means of spectroscopic techniques, and those of 2 and 3 were identified by comparing their spectroscopic data with those reported in the literature. 相似文献
993.
Jin Liu Kelly J. Boarman Natalie L. Wendt Lina M. Cardenas 《Tetrahedron letters》2005,46(30):4953-4956
Photoisomerization of five fluorinated E,E-1-(R-phenyl)-4-phenyl-1,3-butadienes in solution (R = 1: p-monofluoro, 2: m,m′-difluoro, 3: m,m′,p-trifluoro, 4: o,o′,m,m′-tetrafluoro, 5: o,o′,m,m′,p-pentafluoro) was investigated via direct irradiation. Our results indicated that cis-trans photoisomerization of the fluorinated 1,4-diphenyl-1,3-butadienes in the excited singlet state took place exclusively at the CC bonds closer to the fluorine substituents. 相似文献
994.
Jin Chen Lin-xi Zhang A-gen Xia 《高分子科学》2006,(1):13-19
It is important to know the rate of intra-molecular contact formation in proteins in order to understand how proteins fold clearly. Here we investigate the rate of intra-molecular contact formation in short two-dimensional compact polymer chains by calculating the probability distribution p(r) of end-to-end distance r using the enumeration calculation method and HP model on two-dimensional square lattice. The probability distribution of end-to-end distance p(r) of short two-dimensional compact polymers chains may consist of two parts, i.e. p(r) = p1(r) p2(r), where p1(r) and p2(r) are different for small r. The rate of contact formation decreases monotonically with the number of bonds N, and the rate approximately conforms to the scaling relation of k(N) ∝ N-α. Here the value of α increases with the contact radius a and it also depends on the percentage of H (hydrophobic) residues in the sequences of compact chains and the energy parameters of εHH, εHP and εPP . Some comparisons of theoretical predictions with experimental results are also made. This investigation may help us to understand the protein folding. 相似文献
995.
Shin DY Kim HS Min KH Hyun SS Kim SA Huh H Choi EC Choi YH Kim J Choi SH Kim WB Suh YG 《Chemical & pharmaceutical bulletin》2000,48(11):1805-1806
A highly potent anti-MRSA sesquiterpenoid has been isolated from Ulmus davidiana var. japonica, which has been traditionally used to treat infectious diseases in Korea. This naturally occurring antibiotic was identified as mansonone F (1). This compound has been found to be highly active specifically against MRSA and showed an MIC range of 0.39-3.13 microg/ml which is comparable to that of vancomycin. 相似文献
996.
A sensitive and selective method using liquid chromatography with electrospray ionization mass spectrometric detection was
developed for the quantification of bilobalide and ginkgolides in canine plasma. The analytes were extracted with diethyl
ether-dichloromethane-isopropanol (6:3:1, v/v) after spiking the samples with daidzein (internal standard). The lower limit
of quantification (LLOQ) of the method was 2.5 μg L−1 for ginkgolide B and 10.0 μg L−1 for bilabolide, ginkgolide A and ginkgolide C. The accuracy of the method was within 15% of the actual values over a wide
range of plasma concentrations. The intra-day and inter-day precision was better than 15% (R.S.D.). Finally, the LC-ESI-MS
method was successfully applied to study the pharmacokinetics of ginkgolides and bilabolide after administration of Ginkgo biloba extracts to dogs. 相似文献
997.
998.
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1000.
催化动力学光度法测定痕量锰(Ⅱ) 总被引:11,自引:0,他引:11
研究了在Na2HPO4-NaOH介质中,Mn(Ⅱ)催化高碘酸钾氧化镁试剂1[4-(对硝基苯偶氮)间苯二酚]的反应及其动力学条件,建立了一种高灵敏、高选择性测定痕量Mn(Ⅱ)的新方法。可测0.01-2.5μg/25mL范围的锰(Ⅱ),方法的检测限为6.43×10^-11gm/mL。 相似文献