在生物大分子中温度对所激发的孤立子的影响

研究了生物蛋白质分子的温度T≠OK和分子链作非线性振动情况下所产生的相干性集体激发和激发的孤立子的特点,此时这类孤立子以超声速运动、其振幅和传递速度都随温度和非线性振动作用改变,但这种热涨落的存在并未多大影响这类孤立子的稳定性.因而在生物学过程中是很有用的.     

在生物大分子中温度对所激发的孤立子的影响

研究了生物蛋白质分子的温度Ｔ≠ＯＫ和分子链作非线性振动情况下所产生的相干性集体激发和激发的孤立子的特点,此时这类孤立子以超声速运动,其振幅和传递速度都随温度和非线性振动作用改变,但这种热涨落的存在并未多大影响这类孤立子的稳定性,因而在生物学过程中是很有用的。     

在全量子理论下蛋白质分子中激发的孤立子的特征

用全量子力学理论代替过去的半经典半量子理论推导出了在蛋白质分子中激发的、传递生物能量和信息的孤立子的运动方程。把理论建立在可靠的量子理论基础上。并给出了在此情况下孤立子的量子力学特性。     

电离辐射对蛋白质分子作用的量子孤波分析

本文运用量子力学方法对蛋白质分子中孤波传播的非线性动力学特征进行了探讨。研究表明：电离辐射产生的自由基对蛋白质分子的伤害将会对携带能量、信息的孤立子波传播产生较为显著的影响。     

生物体内的自由基

生物体内的自由基罗曼蒋立科（安徽农业大学生物工程系，合肥２３００３６）自由基是游离存在的、带有不成对电子的分子、原子或离子，其化学性质很活泼。在体内虽然不断地产生，但也不断地被消除，正常状态下处于动态平衡。近年来关于自由基的研究已成为有机化学、无机化...     

自由基生物学的近况与展望

自由基是游离存在的、带有不成对电子的分子、原子或离子,而生物自由基则系指与生命现象相关联的自由基.研究这类自由基生物学作用及其意义的学问,称为自由基生物学.这门学问属于亚分子生物学范畴.虽然Szent Gy(?)rgyi早就指出亚分子生物学的重要意义和自由基与化学致癌的关系,但是由于生物自由基寿命短,浓度低,通常的ESR方法都很难研究它,受技术方法的限制,它的发展是缓慢的,所以当时未受到人们应有的重视.近二十年来,分子生物学迅速发展,研究短寿命自由基的技术方法有新的突破,带动     

铁介导的羟自由基对生物分子的损伤机理

活性氧在生物分子如ＤＮＡ,蛋白质及脂质等氧化性损伤中起着非常重要的作用,弱反应生的超氧阴离子自由基和过氧化氢转主为高反应活性的中间体如羟自由基时,过渡金属特别是铁的参与。本文综述了铁介导下羟自由基对生物化学及有关病理学机理具有一定的理论和应用意义。     

电子自旋共振-自由基捕获技术在生物学中的应用

本文结合作者实验室的工作,简要回顾了电子自旋共振-自由基捕获技术在生物领域的应用,包括新型自由基捕获探针的分子设计与合成,以及该技术在细胞、植物体系中的应用实例,并结合该技术的研究现状初步讨论了它的未来发展前景。     

自由基对线粒体DNA的氧化损伤与衰老

自由基是一类氧化剂,对生物具有多种损害作用．衰老的自由基学说是有关衰老机理的诸多学说之一．线粒体DNA组成结构特殊,易受自由基攻击;目前认为,线粒体DNA的氧化损伤是自由基引起衰老的分子基础．     

自由基在抗癌中的作用

关于自由基与肿瘤的关系,早期的研究,注意力集中于自由基在致癌方面的作用。近年来,有些研究发现,自由基也有抗癌作用。这方面的资料虽然不多,但值得注意。本文将近几年这方面的研究发展向读者做一介绍。一、自由基在肿瘤放射治疗中的作用放射线对机体的作用,通常是通过两种方式:(1)直接作用,即射线直接作用于生物分子的损伤效应;(2)间接作用,即射线作用于体内     

Tolypocladium cylindrosporum [Deuteromycetes,Moniliaceae] a new pathogen of mosquito larvae

Tolypocladium cylindrosporum Gams isolated fromAedes australis Erichson in New Zealand, and another strain isolated from soil in Czechoslovakia have shown pathogenicity for larvae of mosquitoes. The infection was transmited with conidia suspended in water and hyphae entered the body of larvae from the midgut. First symptoms of the infection appear 5 days after infection; in 7 days all exposed larvae were killed. Pupae and adult mosquitoes were not infected. Both strains grow and sporulate well on Sabouraud's agar. Somme morphological data show the variability of hyphae, conidiophores and conidia.     

Prediction of a low-frequency mode in bovine pancreatic trypsin inhibitor molecule

One of the frontiers today in molecular biology is to measure, identify and go further to predict the low-frequency internal motion of biological macromolecules, which is crucially important for understanding the dynamic mechanism of various biological functions occurring in such molecules. Based on the theory of continuity model developed recently for dealing with the internal low-frequency motion of a biological macromolecule, it is predicted that the low-frequency phonons with wave number of about 23 cm^?1 might be excited in BPTI molecule.     

红树植物秋茄分子生物学研究进展

秋茄Kandelia obovata Sheue,LiuYong是分布于热带、亚热带海岸带与河口潮间带的常绿红树植物,在海岸生态系统中具有重要的功能和价值。文中综述了近年来国内外关于秋茄分子生物学方面的研究进展,主要包括基于分子标记的秋茄亲缘地理关系与遗传多样性研究,基于双向电泳技术的蛋白质组学研究,以及逆境胁迫响应基因的克隆与功能验证研究;最后还结合当前研究现状展望了秋茄分子生物学未来研究工作的方向。     

Susceptibility to antibiotics of Ureaplasma urealiticum strains isolated at the primorye region]

Susceptibility to antibiotics of Ureaplasma urealyticum strains isolated in Primorye Region and its changes were evaluated. Among the sexually transmited diseases urogenital ureaplasmosis has the leading position in combination with gonorrhoea, trichomoniasis and infections caused by opportunistic pathogens. The spectrum of investigated antibacterial agents included gentamycin, clarithromycin, roxythromycin, azithromycin, doxycycline, three fluoroquinolones of II generation and for cephalosporins of the I and III generations. The most potent activity against U. urealyticum was demonstrated for pefloxacin (67 per cent of susceptible strains), ofloxacin (63 per cent) and roxythmycin (54 per cent). It is concluded that at Primorye Region the drugs of first choice for the urogenital infections therapy are fluoroquinolones.     

Understanding biological functions through molecular networks

The completion of genome sequences and subsequent high-throughput mapping of molecular networks have allowed us to study biology from the network perspective. Experimental, statistical and mathematical modeling approaches have been employed to study the structure, function and dynamics of molecular networks, and begin to reveal important links of various network properties to the functions of the biological systems. In agreement with these functional links, evolutionary selection of a network is apparently based on the function, rather than directly on the structure of the network. Dynamic modularity is one of the prominent features of molecular networks. Taking advantage of such a feature may simplify network-based biological studies through construction of process-specific modular networks and provide functional and mechanistic insights linking genotypic variations to complex traits or diseases, which is likely to be a key approach in the next wave of understanding complex human diseases. With the development of ready-to-use network analysis and modeling tools the networks approaches will be infused into everyday biological research in the near future.     

昆虫分子生物学的一些研究进展：生物钟的基因

昆虫分子生物学的一些研究进展：生物钟的基因翟启慧（中国科学院动物研究所北京１０００８０）生物的许多行为和生理现象有周期性波动,称为生物节律或生物钟。长期以来,这是一个十分吸引人却又难以理解的问题。虽然有大量文献描述生物钟的现象,但对其机理却一无所知。...     

上海地区散发布氏杆菌感染的细菌学及分子鉴定

目的 本研究对我院的1例散发布氏杆菌病患者进行细菌学及分子生物学的分析,并在国内首次尝试了用数目可变串联重复单元(VNTR)分子指纹分析法对其进行了基因分型并和国际流行株进行了分子流行病学比较分析。方法 对临床疑似布氏杆菌病病例作血液细菌培养与生化鉴定,进一步作布氏杆菌特异性基因片段的序列分析鉴定以及利用布氏杆菌基因组中的8个位点构建VNTR指纹图谱,参照国际布氏杆菌VNTR数据库,构建布氏杆菌基因系统树。结果 用细菌学方法确定散发疑似布氏杆菌病病例体内分离到的为布氏杆菌,通过基因序列分析进一步得到证实,但不能鉴定到生物种和生物型。对分离株作VNTR指纹分析提示该散发布氏杆菌病为猪2型布氏杆菌感染所致。结论 通过传统细菌培养方法与布氏杆菌VNTR指纹分析可用于我国布氏杆菌病分子流行病学的系统调查。     

Bringing the physical sciences into your cell biology research

Historically, much of biology was studied by physicists and mathematicians. With the advent of modern molecular biology, a wave of researchers became trained in a new scientific discipline filled with the language of genes, mutants, and the central dogma. These new molecular approaches have provided volumes of information on biomolecules and molecular pathways from the cellular to the organismal level. The challenge now is to determine how this seemingly endless list of components works together to promote the healthy function of complex living systems. This effort requires an interdisciplinary approach by investigators from both the biological and the physical sciences.     

Investigation of biological systems by high resolution 2-mm wave band ESR.

The application of high resolution ESR to the investigation of various biological systems is discussed. The advantages of the technique in the study of structural, conformational and dynamic characteristics have been exemplified by spin-labeled human serum albumin, egg lysozyme, liposome membranes, inverted micelles, alpha-chymotrypsin, cotton fiber and cellulose. The polarity of the microenvironment and the mechanism of molecular mobility of the objects under study have been determined. The combination of high resolution and saturation transfer techniques has been shown to give a detailed analysis of very slow molecular motions in biological objects. Peroxide radicals in biosystems have been identified from their ESR spectra at the 2-mm wave band.     

The biological activity of catfish pancreatic somatostatin

Catfish pancreatic somatostatin, which contains eight additional amino acids on the amino terminus of a tetradecapeptide with considerable homology to tetradecapeptide somatostatin (SRIF), is a naturally occurring homology of the hypothalamic peptide. The purpose of these studies was to determibe the biological activity of this somatostatin homolog. Inhibition of ¹²⁵I-labelled tyr¹-SRIF binding to bovine pituitart plasma membranes by catfish pancreatic somatostatin was approximately 33% that of SRIF. Pancreatic somatostatin has full biological activity measured by inhibition of growth hormone release from isolated rat pituitary cells, but 0.01–0.1% the potency of SRIF. Pancreatic somatostatin at 100 ng/ml produced a 50–60% inhibition of insulin and glucagon secretion from perfused rat pancreas, while SRIF produced comparable inhibition at 10 ng/ml. This report demonstrates that a larger molecular form and natural homolog of SRIF, isolated from fish pancreas, has the same (but reduced) biological activities in rat assay systems as somatostatin originally isolated from sheep hypothalamus.