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目的:考察不同溶媒配制的诺氟沙星对照品溶液能否保存。方法:用紫外分光光度法分别对5℃放置的使用不同溶媒的对照品溶液在0d、10d、20d、30d、40d测定最大吸收波长、吸收值。结果;以0.4%NaOH溶液为溶媒的诺氟沙星对照液于5℃放置40d,最大吸收波长、吸收值均未发生变化(无显著性差异P>0.05)。而以pH4.0醛酸缓冲液、pH7.4磷酸盐缓冲液为溶媒的两种对照液5℃放置40d,最大吸收波长未发生变化,但吸收值明显降低(有显著性差异P<0.05)。结论:用0.4%NaOH溶液配制的诺氟沙星对照品溶液在适宜的条件下(5℃,避光密闭)保存,40d内是稳定的,可继续使用。而用pH4.0醋酸缓冲注和pH7.4磷酸盐缓冲液配制的诺氟沙星对照品溶液则不能保存使用,必须临用新配。 相似文献
114.
AnAnalysisofChromosomeonSterilityCausedbyAzoospermiaorOligospermia¥WuMeiheng;TangWingnuo.(ACTAACADEMIAEMEDICINAENANJING,1995(... 相似文献
115.
本文报道 ̄99mTc-新半乳糖白蛋白( ̄99mTc-NGA)与大鼠肝细胞膜进行体外结合试验。结果表明: ̄99mTc-NGA系与肝细胞膜上的高亲和力低容量(K_1:8.4089×10 ̄9L/mol;R_1:1.7350×10 ̄(-12)mol/mg)和低亲和力高容量(K_2:2.0827×10 ̄8L/mol;R_2:6.9530×10 ̄(-12)mol/mg)2个结合位点相结合,其结合表现出高特异性、可饱和性及对细胞膜蛋白浓度的线性依赖性,具备受体介导结合的基本特征。 ̄(99m)Tc-NGA是一个很有希望的肝受体显像剂。 相似文献
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H Yamanaka E H Willis C A Penning C L Peebles E M Tan D A Carson 《The Journal of clinical investigation》1987,80(3):900-904
The chromatin-bound enzyme poly(ADP-ribose) polymerase (ADPRP) is strongly stimulated by DNA with single- or double-stranded breaks, and transfers the ADP-ribose moiety of NAD to nuclear proteins. The activation of ADPRP is important for DNA repair and replication, and also has been postulated to play a role in the pathogenesis of lymphocyte dysfunction associated with chronic inflammatory diseases, and inborn errors of nucleoside metabolism. We have detected high titers of IgG autoantibodies to the ADPRP protein in six patients with rheumatic complaints. No other autoantibodies were detected in any of the six sera. The specificity of the anti-enzyme antibodies was established by (a) immunoprecipitation of ADPRP activity, (b) immunoprecipitation and immunoblotting of both the native 116-kD enzyme and its proteolytic digestion products. ADPRP was purified from human thymus and calf thymus. The autoantibodies reacted equivalently with both enzymes. The anti-ADPRP antibodies had a distinctive immunofluorescent pattern with HEp-2 cells, reacting intensely with nucleoli and metaphase chromosomes, and diffusely with the nucleus. Autoantibodies to ADPRP have not been described previously. The presence of a specific immune response against an enzyme that has been associated with various immunodeficiency syndromes raises intriguing possibilities concerning the relationship between DNA damage, immunodeficiency, and autoimmunity. 相似文献
118.
E C Tan 《The Journal of dermatologic surgery and oncology》1989,15(3):270-272
The punch technique of repairing pierced earlobe deformities is a practical and simplified alternative to the usual method of repair. The procedure can easily be performed in any dermatology office since the instruments required are very basic. The technique is presented in a series of illustrations, and the results are cosmetically acceptable. 相似文献
119.
Expression of antibody heavy- and light-chain genes by transfection permits the production of monoclonal antibodies with improved biological and antigen-binding properties. The immunoglobulin genes are placed in vectors containing a gene for encoding a protein that provides a biochemically selectable function in eukaryotic cells; these vectors are transfected into myeloma and hybridoma cells. Selection of drug-resistant cells permits the efficient isolation of the rare cells that express the transfected DNA. By placing heavy and light chains on plasmids with different selectable markers, one can deliver heavy- and light-chain genes simultaneously to the same cell. The transfected immunoglobulin genes are efficiently expressed and the proteins produced are a faithful mirror of the genes that were introduced. Using the standard techniques of genetic engineering and gene transfection, we can now produce antibodies of widely varying structures, including chimeric antibodies with segments derived from different species. These antibodies provide useful reagents to study structure-function relationships within the antibody molecule. Ultimately it will be possible to produce a new generation of antibody molecules with improved antigen-binding properties and effector functions. 相似文献
120.
Rabies in Malaysia 总被引:1,自引:0,他引:1
Y S Tan 《The Southeast Asian journal of tropical medicine and public health》1988,19(4):535-536