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951.
952.
蛇毒心脏毒素对动物细胞的遗传损伤和生殖毒性研究 总被引:1,自引:0,他引:1
目的 应用眼镜蛇毒心脏毒素(CTX)作用于小鼠的骨髓细胞和生殖细胞,以探讨CTX对动物体的生殖毒性和遗传毒性。方法 对小鼠腹腔注射不同剂量CTX,通过生殖毒性实验和致突变实验,分析孕鼠的胚胎存活率,骨髓细胞和精母细胞的染色体畸变率。结果:CTX能影响胎鼠的生长发育,使孕鼠的增重和活胎率均明显地降低(P〈0.001),染色体畸变实验显示CTX0.4mg/kg剂量上精母细胞多倍体和非整倍体细胞数目增高 相似文献
953.
毒蛇咬伤的中西医结合用药分析 总被引:3,自引:4,他引:3
目的探讨毒蛇咬伤的临床中西医结合用药状况。方法随机抽取本院近年毒蛇咬伤病例120份进行统计与分析。结果在毒蛇咬伤的临床用药中,以清热解毒、利水消肿、益气养血的中药与抗蛇毒、抗炎、抗过敏、抗休克、利尿排毒和保护脏器功能的西药结合用率达100%。结论中西医结合治疗蛇伤,有利于内外同治,标本兼治,提高临床治愈率。 相似文献
954.
Fan J Wang X Wu L Matsumoto SI Liang J Koike T Ichikawa T Sun H Shikama H Sasaguri Y Watanabe T 《Transgenic research》2004,13(3):261-269
Increased matrix metalloproteinase-12 (MMP-12) has been implicated in atherosclerosis and many other inflammatory processes.
To define MMP-12 functions in vivo, we generated transgenic rabbits that expressed human (h) MMP-12 gene under the control of a macrophage-specific promoter,
the human scavenger receptor promoter. Two transgenic founder rabbits were found to have hMMP-12 transgene integration by
Southern blot analysis. hMMP-12 mRNA was expressed in peritoneal and alveolar macrophages, and in tissues enriched in macrophages
in transgenic rabbits. High levels of hMMP-12 protein were detected in the conditioned media of cultured peritoneal and alveolar
macrophages from transgenic rabbits. Zymography showed that hMMP-12 secreted from macrophages possessed enzymatic activity
toward β-casein. To evaluate the expression of hMMP-12 in inflammatory sites, we used carrageenan-induced granulomas as an
in vivo model for tissue macrophages and foam cells. Granuloma size in transgenic rabbits was significantly increased compared to
that in control rabbits, and histological examination revealed that granulomas of transgenic rabbits were enriched in macrophages
associated with increased hMMP-12 expression. We believe that this transgenic rabbit model with increased expression of hMMP-12
may become a useful model for further mechanistic studies of MMP-12 in inflammatory diseases and cancer invasion; it is also
an ideal model for testing the in vivo action of MMP-12 inhibitors. 相似文献
955.
Ivan?H?StillEmail author Ananthalakshmy?K?Vettaikkorumakankauv Anthony?DiMatteo Ping?Liang 《BMC evolutionary biology》2004,4(1):16
Background
Examination of ancient gene families can provide an insight into how the evolution of gene structure can relate to function. Functional homologs of the evolutionarily conserved transforming acidic coiled coil (TACC) gene family are present in organisms from yeast to man. However, correlations between functional interactions and the evolution of these proteins have yet to be determined. 相似文献956.
NDRG1 is necessary for p53-dependent apoptosis 总被引:11,自引:0,他引:11
Stein S Thomas EK Herzog B Westfall MD Rocheleau JV Jackson RS Wang M Liang P 《The Journal of biological chemistry》2004,279(47):48930-48940
957.
Inhibition of hepatitis C virus-like particle binding to target cells by antiviral antibodies in acute and chronic hepatitis C 总被引:7,自引:0,他引:7
Steinmann D Barth H Gissler B Schürmann P Adah MI Gerlach JT Pape GR Depla E Jacobs D Maertens G Patel AH Inchauspé G Liang TJ Blum HE Baumert TF 《Journal of virology》2004,78(17):9030-9040
Hepatitis C virus (HCV) is a leading cause of chronic viral hepatitis worldwide. The study of antibody-mediated virus neutralization has been hampered by the lack of an efficient and high-throughput cell culture system for the study of virus neutralization. The HCV structural proteins have been shown to assemble into noninfectious HCV-like particles (HCV-LPs). Similar to serum-derived virions, HCV-LPs bind and enter human hepatocytes and hepatoma cell lines. In this study, we developed an HCV-LP-based model system for a systematic functional analysis of antiviral antibodies from patients with acute or chronic hepatitis C. We demonstrate that cellular HCV-LP binding was specifically inhibited by antiviral antibodies from patients with acute or chronic hepatitis C in a dose-dependent manner. Using a library of homologous overlapping envelope peptides covering the entire HCV envelope, we identified an epitope in the N-terminal E2 region (SQKIQLVNTNGSWHI; amino acid positions 408 to 422) as one target of human antiviral antibodies inhibiting cellular particle binding. Using a large panel of serum samples from patients with acute and chronic hepatitis C, we demonstrated that the presence of antibodies with inhibition of binding activity was not associated with viral clearance. In conclusion, antibody-mediated inhibition of cellular HCV-LP binding represents a convenient system for the functional characterization of human anti-HCV antibodies, allowing the mapping of envelope neutralization epitopes targeted by naturally occurring antiviral antibodies. 相似文献
958.
Lignocelluloses prepared from woody tea stalk, pine sawdust and sugarcane bagasse were used as adsorbents to isolate decaffeinated catechins from tea extracts and compared with synthetic macroporous resin HPD 600. HPD 600 had the highest adsorption capacity to catechins, followed by tea stalk lignocellulose while lignocelluloses of pine sawdust and bagasse the least. Tea stalk lignocellulose absorbed preferentially tea catechins and showed a good selectivity. HPD 600 absorbed caffeine and tea catechins simultaneously. The kinetics data of tea stalk lignocellulose showed a good fit with the Langmuir isotherm model. It is considered that tea stalk lignocellulose is an alternative low-cost adsorbent for preparing decaffeinated tea catechins. 相似文献
959.
本文报告一种新的腺苷亲和层析凝胶的合成方法。利用这种凝胶可从大鼠心脏、肝脏及小牛主动脉平滑肌的水溶部份分离出几种腺苷结合蛋白质,其亚基分子量(据SDS-PAGE)分别为35,000、37,000、46,000、43,000及15,300Dal。现已证明,35,000Dal蛋白质是乳酸脱氢酶及苹果酸脱氢酶,43,000Dal蛋白质是腺苷激酶,46,000Dal蛋白质可能是S-腺苷同型半胱氨酸水解酶。15,000Dal蛋白质前人未有报道。它对腺苷具有高度特导性和亲和力,推测是腺苷的细胞内受体和/或载体。测定了这种低分子量腺苷结合蛋白质的氨基酸组成及某些物理常数:pI=6.5;沉降系数2.42S,微分比容0.727cm~3/g,与腺苷复合物的解离常数K_D=2.3μM。 相似文献
960.
有机酸去除污泥重金属前后硝态氮和铵态氮浓度变化 总被引:1,自引:0,他引:1
研究了柠檬酸、草酸和乙酸溶液对污泥中重金属(Cd、Pb、Cu和Zn)的去除效果,以及处理前后析出液和污泥中硝态氮和铵态氮的浓度变化.结果表明,0.8mol.L-1柠檬酸溶液可去除污泥中76.0%的Pb和92.5%的Zn,是较好的重金属去除剂.污泥经有机酸处理后,有大量的硝态氮和铵态氮溶解于析出液中,与加入蒸馏水的对照处理相比,有机酸可大幅度增加析出液中铵态氮的含量,减少硝态氮含量.由于污泥处理过程中有其他形态的氮的转化,处理后污泥中仍含有较高浓度的硝态氮和铵态氮.0.5mol.L-1草酸处理的析出液中硝态氮和铵态氮浓度分别为2.8和888.1mg.L-1,且重金属含量不高,可作为较好的液体肥料进行回收利用. 相似文献