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31.
0 引言 我科 1996 / 1998分别应用消痔灵与强的松龙混合液、消痔灵液、强的松龙液行鼻息肉内 ,鼻息肉蒂部注射治疗鼻息肉各 5 0例 ,并设对照组为鼻腔滴入及口服类固醇激素 5 0例 ,合计 2 0 0例 ,观察并对比其疗效 .1 对象和方法1.1 对象 男 12 8例 ,女 72例 ,年龄 8~ 78(平均 38)岁 ,病程 32 a~ 45 (平均 4.5 ) a.其中在本次治疗前做过一次鼻息肉摘除术后复发的 2 7例 ,做过 2次或 2次以上手术的 12例 .主要症状为鼻塞、流脓涕、头痛及嗅觉减退 .全部病例治疗前均行鼻窦 X线拍片 ,其中上颌窦炎 12 5例、筛窦炎 5 8例、蝶窦炎 2例、… 相似文献
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Skin tumors induced in mice by initiation-promotion (2 microg DMBA-2 microg
TPA) protocols were found to be under multigenic control. Eighty- one N2
mice from the cross (BALB/cAnPt x SENCARA/Pt)F1 x SENCARA/Pt that were
either solidly resistant (no papillomas) or highly susceptible (> or = 7
papillomas/mouse) were subjected to a 'genome scan' using 89 microsatellite
markers to check for associations with susceptible and resistant
phenotypes. A locus on Chr 5 (Skts4) was found to control the
susceptibility of SENCARA/Pt mice and the resistance of BALB/cAnPt mice to
papilloma formation. In addition, higher than expected linkage scores were
seen for the markers D9Mit271, D11Mit268 and D12Mit56. Further work is
required to establish whether genes determining papilloma formation are
located in these regions of the genome. In general, no evidence was seen
for loss of heterozygosity in microsatellite markers on Chrs 5, 9 and 11 in
17 microdissected papillomas from (BALB/c x SENCARA)F1 hybrid mice.
相似文献
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In order to enhance the immune efficacy of DNA vaccination, experiments were conducted to investigate the regulating effects of Bacillus Calmette-Guerin (BCG)-DNA as an adjuvant on immune responses of mice against foot-and-mouth disease (FMD), Aujeszky's disease (AID) and classical swine fever (CSF). BCG-DNA was purified from BCG by ion-exchange chromatography. Three DNA vaccines (pVSG, pVgD and pVE2) against the respective infection were constructed, and BCGDNA was coimmunized to mice by muscle injection. The results showed that titres of specific immunoglobulin (Ig)G to the vaccines mounted remarkably in the sera of the adjuvant covaccinated mice (P〈0.01). Antibody isotype IgG2a and IgG1 also increased, respectively, in mice coimmunized with BCG-DNA compared with those of the control groups (P〈0.01). Cellular immune cytokine interferon-gamma and cytotoxic T lymphocytes were detected in coimmunized BCG-DNA groups (P〈0. 05). Whereas interleukin-4, humoral immune cytokine, was not significant (P〉 0. 05). These results suggest that codelivery of BCG-DNA with DNA vaccines against FMD, AjD and CSF can enhance the induction of antigen-specific, especially, cell-mediated immunity. 相似文献
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Jau-Cheng Liou Yun-Ching Cheng Kai-Hsiang Kang Yuan-Ping Chu Chen-Chung Yang Long-Sen Chang 《Toxicon》2004,43(3):341-346
In the present study, Xenopus nerve-muscle cultures were used to explore the functional roles of A chain (a phospholipase A(2) subunit) and B chain (a non-phospholipase A(2) subunit) of Bungarus multicinctus beta-bungarotoxin. It was found that beta-bungarotoxin induced an increment of the frequency of spontaneous synaptic currents (SSCs) in the nerve-muscle cultures. Modification of beta-bungarotoxin with pyridoxal-5'-phosphate or substitution of Ca(2+) with Ba(2+) in buffer abolished the phospholipase A(2) activity of beta-bungarotoxin and the facilitatory phase of SSC as well. Antibodies that were directed specifically against A chain or B chain effectively inhibited phospholipase A(2) activity, and as a consequence the SSC frequency was not greatly different from the control rate. These results suggest that both A and B chains are indispensable parts of beta-bungarotoxin for inducing the facilitation of SSC frequency with Xenopus nerve-muscle cultures. 相似文献
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Long-Sen Chang Pei-Fung Wu Jau-Cheng Liou Wen-Hsien Chiang-Lin Chen-Chung Yang 《Toxicon》2004,44(5):491-497
Notexin, a presynaptic phospholipase A2 (PLA2) neurotoxin isolated from Notechis scutatus scutatus venom, was inactivated by arginine-specific reagents, phenylglyoxal and 1,2-cyclohexanedione. Kinetic analyses of the modification reaction revealed that the inactivation of notexin followed pseudo-first order kinetics and the loss of PLA2 activity was correlated with the incorporation of one molecule of modification reagent per toxin molecule. However, the results of amino acid analysis and sequence determination revealed that two arginine residues at positions 43 and 79 of notexin were modified simultaneously. Modification of the arginine residues was accompanied with a decrease in the ability to inhibit the indirectly evoked contraction of chick biventer cervicis muscle and bind with synaptic membranes. The secondary structure of the toxin molecule did not significantly change after modification with phenylglyoxal as revealed by the CD spectra. The modified derivative retained its affinity for Ca2+, indicating that the modified arginine residues did not participate in Ca2+ -binding. Together with the notion that Arg-43 and Arg-79 of notexin are located in the proximity of its catalytic site and toxic site, respectively, our results suggest that modification of Arg-43 and Arg-79 should differently contribute to the observed decrease in the PLA2 activity and neurotoxic effect of notexin. 相似文献
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