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81.
本文研究聚丁二炔(Polydiacetylene)中的量子成核和热成核相变过程。在从PDB相向PDA相的相变过程中。会出现一个畴壁;相反,在从PDA相向PDB相的相变过程中,会出现一个反畴壁。我们认为,畴壁的形成是一种涨落的结果;利用统计物理的方法,对两种成核过程进行了详细的讨论,发现在ETCD-PD中,主要是热成核相变;而在ETDU-PD中,主要是量子成核相变,与实验事实符合。图5,参13 相似文献
82.
邝向军 《四川理工学院学报(自然科学版)》2006,19(2):75-78
考虑金属中的电子位移极化,利用谐振束缚电子模型,导出了金属中相对介电常数的表达式,并讨论低频极限和高频极限两种重要的特殊情况,对关于金属介电常数的一些说法作出了解释,从而对金属介电常数有了更为全面的理解。 相似文献
83.
CHEN Ciping 《系统科学与复杂性》1992,(2)
We give some answers to the following question:If the binding numberof a graph G is more than 1+(a-1)/b,does G have an [a,b] -factor? 相似文献
84.
为研究环境化合物与雌激素受体的相互作用,在大肠杆菌中异源表达了人雌激素受体ERβ的配体结合区(hERβ-LBD)蛋白。在诱导剂(IPTG)浓度为0.2mmol.L-1,培养温度25℃,诱导时间为8h的优化表达条件下,经亲和色谱法纯化后,hERβ(LBD蛋白的产量可达236mg.L-1. 相似文献
85.
Genetic and environmental influences on behavioral and neurochemical aspects of emotionality in rats
Summary Three pairings of rats (two derived from divergent, selective breeding and one from divergent environmental conditions) were compared with regard to behavioral and hormonal parameters. Striking differences were observed: results obtained in our own laboratory as well as those found in a review of the literature pointed to higher emotionality (e.g., increased defecation and corticosterone secretion, etc.) in Roman low-avoidance, Wistar-Kyoto and group-housed rats, as compared to their respective counterparts, Roman high-avoidance, spontaneously hypertensive, and individually housed Wistar rats. Concomitant receptor binding studies reviewed here (3H-diazepam- and3H-imipramine-binding sites) have revelaed, however, less consistent intrapair differences. 相似文献
86.
A. Dobozy L. Kemény M. Csató J. Hunyadi A. Sz. Kenderessy N. Simon 《Cellular and molecular life sciences : CMLS》1984,40(12):1403-1404
Summary An enhancement effect of mouse erythrocyte rosette forming (MERF) cells on the production of migration inhibitory factor, chemotactic factor for neutrophils and skin reactive factor in T-lymphocyte cultures stimulated with the purified protein derivative of tuberculin was observed. We consider it likely that the MERF cells, possessing the appropriate cell surface constituents to construct an immunogenic moiety, present antigen on their surfaces to elicit lymphokine production.This work was supported by the Scientific Research Council, Ministry of Health, Hungary, Code No. 421030401 1/s 相似文献
87.
Eudes R Lehn P Férec C Mornon JP Callebaut I 《Cellular and molecular life sciences : CMLS》2005,62(18):2112-2123
Defective function of the cystic fibrosis (CF) transmembrane conductance regulator (CFTR) causes CF, the most frequent lethal inherited disease among the Caucasian population. The structure of this chloride ion channel includes two nucleotide-binding domains (NBDs), whose ATPase activity controls channel gating. Recently, the experimental structures of mouse and human CFTR NBD1 and our model of the human CFTR NBD1/NBD2 heterodimer have provided new insights into specific structural features of the CFTR NBD dimer. In the present work, we provide a structural classification of CF-causing mutations which may complement the existing functional classification. Our analysis also identified amino acid residues which may play a critical role in interdomain interaction and are located at the NBD1-NBD2 interface or on the surface of the dimer. In particular, a cluster of aromatic amino acids, which includes F508 and straddles the two NBDs, might be directly involved in the interaction of the NBD1/NBD2 heterodimer with the channel-forming membrane-spanning domains.Received 24 May 2005; received after revision 13 June 2005; accepted 18 June 2005 相似文献
88.
设G是一个图,若删除G中任意n’个顶点的剩余子图依然是分数k-消去图,则称G为分数(k,n')-临界消去图.笔者证明了若k≥2,n,≥0,bind(G)≥^(n'+1)且6(G)≥k+n'+1,则G是分数(k,n')-临界消去图. 相似文献
89.
用光谱法研究了带有吩嗪基团的酚藏花红与DNA的相互作用.研究表明,酚藏花红能嵌入到DNA骨架的碱基对之间,在实验允许的误差范围内,用不同的光谱法测得的结合常数一致,均为104L·mol-1数量级,结合位点数约为7.阴离子KI的荧光猝灭实验进一步证实了酚藏花红与DNA之间的嵌入作用.该研究为以DNA为靶的药物设计提供了一种新的嵌入剂功能团. 相似文献
90.
Binding assay is a convenient, simple, inexpensive, and rapid method that can be used for rapid screening insecticidal compounds. The present study examines 6 compounds for their inhibition of [^3H] EBOB bound to housefly-head membranes, of which 3 compounds have potency for housefly-head membranes. 相似文献