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51.
许明 《中山大学学报(自然科学版)》2001,40(1):13-15
研究弱核条件下的T(b)定理,并且在b=1+ia′(x),-M<a′<M,M>0以及b是仿增长函数情况下,利用小波证明了T(b)定理. 相似文献
52.
目的 比较正常血糖长爪沙鼠和自发遗传性糖尿病长爪沙鼠肝脏、肾脏、骨骼肌和脑组织中钠通道β亚基(sodium channel beta subunit 3 gene,Scn3b)的表达差异。方法 选取正常血糖长爪沙鼠和自发遗传性糖尿病长爪沙鼠各6只,分别采集动物的肝脏、肾脏、骨骼肌和脑组织,利用Real-time PCR和Western blotting检测Scn3b在各组织中的mRNA和蛋白表达水平。结果 与正常血糖动物相比,在糖尿病长爪沙鼠肝脏和脑组织中,Scn3b mRNA和蛋白水平表达均下降,其中在肝脏具显著性差异。结论 Scn3b在糖尿病长爪沙鼠肝脏和脑组织中表达减少,提示在肝脏和脑组织中Scn3b的异常表达可能参与长爪沙鼠糖尿病的发生。 相似文献
53.
比较了b/s结构和c/s结构的优缺点,以及实行二者结合的优缺点;并对二者如何进行结合进行了讨论;研究了系统中涉及的角色,工作流,数据的数据模型,系统的分层体系,从系统分析的层次上为实际管理软件的实现提供指导. 相似文献
54.
The binding and electron transfer between wild type, E44A, E56A, E44/56A, E44/48/56A/D60A and F35Y variants of cytochrome b5 and cytochrome c were studied. When mixed with cytochrome c, the cytochrome b, E44/48/56A/D60A did not show the typical UV-vis difference spectrum of absorption, indicating that the alteration of the surface electrostatic potential obviously influenced the spectrum. The electron transfer rates of wild type cytochrome bj, its variants and cytochrome c at different temperature and ionic strength exhibited an order of F35Y > wild type > E56A > E44A > E44/48/56A/D60A. The enthalpy and entropy of the reaction did not change obviously, suggesting that the mutation did not significantly disturb the electron transfer conformation. The investigation of electron transfer rate constants at different ionic strength demonstrated that electrostatic interaction obviously affected the electron transfer process. The significant difference of Cyt b, F35Y and E44/48/56A/D60A from the wild type protein further confirmed the great importance of the electrostatic interaction in the protein electron transfer. 相似文献
55.
5-FU、海藻多糖、黄芪多糖复方抗癌制剂抗肿瘤药理作用的研究 总被引:3,自引:2,他引:1
由5一FU、海藻多糖、黄芪多糖组成复方抗癌制剂(以下简称复方)。对小鼠体内移植肉瘤(S180)、小鼠肝癌(H22)均有显著的抑制作用,与化疗药物5一FU相比,抑瘤作用增强,毒副作用降低。复方可提高荷瘤小鼠红细胞免疫功能,减轻化疗药物对机体的免疫抑制作用。 相似文献
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57.
J. Zídková V. Větvička P. Rossmann V. Dlabač J. Stránsky 《Cellular and molecular life sciences : CMLS》1984,40(9):975-977
Summary The third component of the pig complement system (C3) was isolated in hemolytically active form and characterized. The C3 component is a -globulin with the molecular weight of 191,000 and is composed of 2 non-identical polypeptide chains of Mt 112,000 and 74,000. The isolated C3 can be used for the detection of the C3b receptor on the membranes of heterologous peritoneal macrophages. 相似文献
58.
Investigations into the perplexing interrelationship of the Genus Takifugu Abe, 1949 (Tetraodontiformes, Tetraodontidae) 总被引:1,自引:0,他引:1
《科学通报(英文版)》2008,(2)
The phylogenetic relationships within the genus Takifugu Abe, 1949 (Tetraodontiformes, Tetraodonti- dae) remain unresolved. Because of the use of Takifugu as model organisms, the resolution of these relationships is crucial for the interpretation of evolutionary trends in biology. Pufferfishes of this ge- nus are comprised of a comparatively small number of species and are mainly distributed along the coastal region of the western part of the Sea of Japan and the coastline of China. Mitochondrial gene sequences were employed to test the phylogenetic hypotheses within the genus. Seventeen species of the genus were examined. Molecular phylogenetic trees were constructed using the maximum parsi- mony, neighbor-joining, maximum likelihood and Bayesian methods. Our hypothesis of internal relationships within the genus differs from previous hypotheses. Our results indicate that (1) the genus Takifugu is a monophyletic assemblage; (2) the genus is divided into 6 subgroups based on the mo- lecular data; and (3) there is low genetic diversity among the species within this genus. In addition, speciation within Takifugu appears to be driven by hybridization and isolation by distribution. Our re- sults also suggested that the taxonomy in the genus should be clarified based on both molecular and morphological data. 相似文献
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