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1.
髓性白血病细胞HL60自发超微弱生物光子辐射研究   总被引:3,自引:0,他引:3  
采用光子计数成像采集系统(PIAS)对髓性白血病细胞HL60自发的超微弱生物光子辐射进行了初步研究,获得了HL60细胞的生物光子强度与培养时间及细胞密度的关系。研究表明,HL60细胞的生物光子强度反映了细胞繁殖规律性及新陈代谢状况。为进一步探索肿瘤细胞与抗癌药物作用的生物光子效应,我们把TNF-β(肿瘤坏死因子)对悬浮HL60细胞进行处理,发现比同性质无TNF-β药物的对照组有更强的的超微弱光子辐射。  相似文献   

2.
水稻和玉米幼苗的超弱生物光子发射比较研究   总被引:1,自引:0,他引:1  
利用自制的超高灵敏度超弱生物光子发射(ultraweak biphoton emissions,UBE)二维图象系统观测比较了水稻(Orza sativaL.)和玉米(Zea maysL.)不同品种种子萌发过程中超弱生物光子发射的变化。发现普通饲料玉米(阳单82)和高杆水稻品种(金科占)的种苗及+1叶的UBE分别比超甜玉米品种(穗甜1号、3号)和矮杆水稻品种(矮珍占)低,而前者的UBE衰减比后者要快,进一步证实超弱生物光子发射是十分灵敏的,且其差别的出现远远早于其它生物学指标,这种特性可能具有普遍性。  相似文献   

3.
《激光生物学报》2000,9(1):68-74
激光热疗中,激光与生物组织相互作用研究主要包含两方面:光子在生物组织中的迁移规律,以及光生扫热在生物组织在的传导。对前者的描述主要为,基于传输理论的解析法和Monte ̄Carlo模拟,生物组织中光子迁移规律的研究能定量描述组织中的光分布,并进一步获得生物组织中的热分布;考虑到了生物组织特性,所建立了生物组织中温度场分布及变化规律。光子迁移与生物传热理论是研究激光热序不可分割的传热模型,全面描述了生  相似文献   

4.
本文研制了用生物倒置显微镜和以微通道板为核心的超高灵敏度光电成像系统组成的光子计数显微成像系统,此系统具有高空间放大倍数(160×)和极高的光子放大倍数(107),可探测到大小为μm量级,发光强度为100光子/秒的发光图像。应用此系统拍摄到了单个明亮发光杆菌(Photobacteriumphosphoreum)的发光图像,图像显示明亮发光杆菌的大小为2.4×0.60(μm)2,单个细菌的发光强度在100光子/秒量级。上述实验为明亮杆菌在环境保护中的应用提供了基本参数,也为进一步从细胞水平上研究发光细菌提供了可能。  相似文献   

5.
生物科学研究中的激光多光子显微技术   总被引:1,自引:1,他引:0  
本文综述了生物科学中近红外(NIR)多光子激光扫描显微技术的进展,其中包括:多光子显微特点,激光光源,荧光寿命的测量,多光子多色实时杂化荧光(FISH),非人侵性活体光学解剖,植物学中的多光子显微技术,细胞的多光子显微损伤、皮米非入侵和非接触性外科手术等。  相似文献   

6.
生物光子发射(PE)方法是揭示生命活动的一种非损伤方法。由于机理不清,仅获有限的认同。根据Dicke近似,顾樵曾经提出PE的全量子理论。然而,Dicke近似不适合生物系统。本文在不引入Dicke近似的前提下,利用量子化学和半径典辐射理论研究了PE的全同粒子模型。结果表明,全同粒子会成相干态,其中超辐射态的光子发射几率是粒子数的平方和三次方的线性函数。本文结论成功地解了细胞分裂和细胞癌变等生命活动的PE现象和外界因素对PE现象的影响。  相似文献   

7.
杨美娜  韩金祥 《生物磁学》2011,(8):1598-1600
生物光子辐射来自生物分子从高能态向低能态的跃迁,它提供了有机体代谢及能量转化的重要信息,生物光子对生命系统内部的变化及外界环境的影响有高度的敏感性,生物光子的探测和分析能够揭示系统内部的细节变化,展示外界环境的微弱影响。本文就近年来生物光子辐射研究的热点与进展作一简要综述。  相似文献   

8.
生物光子辐射的研究进展   总被引:1,自引:0,他引:1       下载免费PDF全文
生物光子辐射来自生物分子从高能态向低能态的跃迁,它提供了有机体代谢及能量转化的重要信息,生物光子对生命系统内部的变化及外界环境的影响有高度的敏感性,生物光子的探测和分析能够揭示系统内部的细节变化,展示外界环境的微弱影响。本文就近年来生物光子辐射研究的热点与进展作一简要综述。  相似文献   

9.
采用光子计数成像系统(PIAS)对植物幼苗萌发过程的超弱发光进行观察。结果表明,自发光子长时间积累可形成二维图象;光子计数和采集图象均可得到植物体的自发发光;通过实验探测到幼苗的根,叶在同一平面图象有不同的发光表现;光子成像系统可客观地比较生物自发超弱发光,为进一步研究超弱发光机理提供实验基础。  相似文献   

10.
《微生物学通报》2007,34(3):599-599
生物光子辐射是一个普遍的生命现象,存在于各种动物、植物、藻类及微生物系统之中。生物光子学是一门新兴的交叉学科,涉及分子生物学、生物化学、量子光学、统计物理学及光电探测理论等。本书系统阐述了生物光子辐射的相干性理论、量子理论、半经典理论及生物光子统计理论,并全面介绍了生物光子检测技术在食品安全与质量检验、水质分析与环境监测、医疗科技、药物性能及效力的研究和农业科学等领域的应用。本书可作为相关专业的教师、研究生等的数学参考用书,也可作为相关技术人员的参考材料。  相似文献   

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正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases  相似文献   

14.
Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.  相似文献   

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16.
The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.  相似文献   

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18.
For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

19.
Å. Berg 《Bird Study》2013,60(2):153-165
CapsuleThe amount of forest (at local and landscape scales) and occurrence of residual habitats at the local scale are shown to be the major factors influencing bird community composition in farmland–forest landscapes in central Sweden.

Aims To investigate the importance of local habitat and landscape structure for breeding birds in farmland–forest landscapes in central Sweden.

Methods Breeding birds were censused at 292 points. A detailed habitat mapping was made within 300 m of the points. Within a 300–600 m radius only two major habitats (forests and arable fields) were identified.

Results Cluster analyses of bird communities identified three site types that also differed in habitat composition: (i) partially forested sites in forested landscapes; (ii) heterogeneous sites with residual habitats in mosaic landscapes; and (iii) field-dominated farmland sites in open landscapes. A total of 19 of 25 farmland bird species (restricted to farmland or using both farmland and forest) had the highest abundance in farmland sites with mosaics of forest and farmland, while only six farmland species had the highest abundance in field-dominated sites. The bird community changed from being dominated by farmland species to being dominated by forest species (common in forest landscapes without farmland) at small proportions (10–20%) of forest at the local scale. A major difference in habitat composition between heterogeneous and field-dominated sites was the occurrence of different residual habitats (e.g. shrubby areas and seminatural grasslands). These habitats seemed to influence bird community composition more than land-use, despite covering <10% of the area. Seminatural grasslands were important for bird community composition and species-richness, but grazing seemed to be less important. Among different land-use types, cereal crops were the least preferred fields. Set-asides with tall vegetation and short rotation coppices were positively associated with species-richness of farmland birds.

Conclusion In general, the composition of the landscape was important for bird community composition, although amount and distribution of forests, occurrence of residual habitats and land-use of fields at the local scale had the strongest influence on bird community composition. The possible implications of these patterns for managing farmland–forest landscapes are discussed.  相似文献   

20.
This work describes the isolation and characterization of twenty-nine compounds from the fruits of Rhus typhina L., including eleven flavonoids (1–11), eleven phenols (12–22), two pentacyclic triterpenes (23–24), two organic acids (25–26), one lumichrome (27), one courmarin (28) and one pyrimidine (29) on the basis of their spectroscopic data. Compounds apigenin (1), daidzein (4), orobol (5), 3′, 5, 5′, 7-tetrahydroxyflavanone (6), naringenin (7), butein (8), (-)-catechin (9), quercetin-3-O-α-L-(3″-O-galloyl)-rhamnoside (11), 2-hydroxybenzoic acid (13), 4-hydroxybenzaldehyde (14), vanillin (15), methyl 3,4-dihydroxybenzoate (16), 3,5-dihydroxybenzamide (18), tyrosol (19), caffeic acid (20), 3-(2,4,6-trihydroxyphenyl)-1-(4-hydroxyphenyl)-propan-1-one (21), phlorizin (22), friedelin (23), oleanolic acid (24), 4,4-dimethyl-heptanedioic acid (25), anthranilic acid (26), lumichrome (27), scoparone (28) and uracil (29) have not been recorded before in this plant. This is the first report on the occurrence of compounds 4–7, 9, 11, 13–14, 16, 18–21, 25–29 from the genus Rhus. Moreover, the chemotaxonomic significance of these isolated compounds was also summarized.  相似文献   

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